HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Figures Only Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Orel, S. G. Articles by Schnall, M. D. Search for Related Content PubMed PubMed Citation Articles by Orel, S. G. Articles by Schnall, M. D.

MR Imaging of the Breast for the Detection, Diagnosis, and Staging of Breast Cancer¹

¹ From the Department of Radiology, Hospital of the University of Pennsylvania, 3400 Spruce St, Philadelphia, PA 19104. Received June 12, 2000; revision requested July 17; revision received September 14; accepted October 2. Address correspondence to S.G.O. (e-mail: orel@oasis.rad.upenn.edu).

	ABSTRACT

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
With the introduction of contrast agents, advances in surface coil technology, and development of new imaging protocols, contrast agent–enhanced magnetic resonance (MR) imaging has emerged as a promising modality for detection, diagnosis, and staging of breast cancer. The reported sensitivity of MR imaging for the visualization of invasive cancer has approached 100%. There are many examples in the literature of MR imaging–demonstrated mammographically, sonographically, and clinically occult breast cancer. Often, breast cancer detected on MR images has resulted in a change in patient care. Despite these results, there are many unresolved issues, including no defined standard technique for contrast-enhanced breast MR imaging, no standard interpretation criteria for evaluating such studies, no consensus on what constitutes clinically important enhancement, and no clearly defined clinical indications for the use of MR imaging. Furthermore, this technology remains costly, and issues of cost-effectiveness and cost competition from percutaneous biopsy have yet to be fully addressed. These factors along with the lack of commercially available MR imaging–guided localization and biopsy systems have slowed the transfer of this imaging technology from research centers to clinical breast imaging practices. Technical requirements, potential clinical applications, and potential pitfalls and limitations of contrast-enhanced MR imaging as a method to help detect, diagnose, and stage breast cancer will be described.

Index terms: Breast, MR, 00.121411, 00.121412, 00.121415, 00.12143 • Breast neoplasms, diagnosis, 00.31, 00.32, 00.81 • Breast neoplasms, MR, 00.121411, 00.121412, 00.121415, 00.12143 • Breast neoplasms, staging • State of the Art

	INTRODUCTION

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
Over the past 2 decades, tremendous advances have been made in the field of magnetic resonance (MR) imaging of the breast—from early experience, prior to use of contrast agents, that suggested that MR imaging had little to offer as a breast imaging method, to more recent experience that has demonstrated not only that breast cancer can be visualized on MR images but also that mammographically and clinically occult breast cancer can be detected on MR images. Developments have been made in surface coil technology, resulting in improved spatial resolution, and in imaging protocols, resulting in improved temporal resolution. Development of MR-guided breast biopsy techniques continues.

Even with all of the advances that have been made, however, MR imaging of the breast as a method to detect and stage breast cancer is a technology in development. Several unresolved issues remain. There is, as yet, no defined "standard" or "optimal" technique for the performance of contrast agent–enhanced MR imaging of the breast. There are no standard interpretation criteria for evaluating breast MR imaging studies and no unifying definition of what constitutes potentially clinically important contrast enhancement. These factors, along with the lack of commercially available MR imaging–guided localization and biopsy systems, have slowed the transfer of this imaging technology from research centers to clinical breast imaging practices.

There are also other unresolved issues. There are no well-established indications for MR imaging of the breast. When should MR imaging be used? Should MR imaging be used only as an adjunctive diagnostic test or should it be used for breast cancer screening? Which patients would benefit most from MR imaging? Are breast cancers detected only with MR imaging of clinically important cancers? Even if MR imaging can be used to detect breast cancer, will this expensive imaging test be cost-effective? Clinical investigations addressing these and many other questions continue. The goal of this article is to describe the technical factors involved in performing contrast-enhanced breast MR imaging; to review the multitude of proposed methods for interpreting these MR studies; and to discuss potential clinical applications, pitfalls, and limitations of contrast-enhanced MR imaging as an imaging tool to help detect, diagnose, and stage breast cancer.

	BREAST MR IMAGING TECHNIQUE

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
Hardware
To date, most of the breast MR imaging studies that have been reported in the literature have been performed with high-field-strength (1.0–1.5-T) MR imaging systems (1–11). The open architecture and low cost of lower field-strength open MR systems is potentially very appealing for breast MR imaging (12). There are, however, several factors that are encountered when attempting to perform contrast-enhanced breast MR imaging at lower field strength. One concern is the signal-to-noise ratio. Low-field-strength systems provide an inherently lower signal-to-noise ratio per unit time of sampling data. In most applications of low-field-strength imaging, a lower imaging bandwidth is used to provide adequate signal-to-noise ratio for imaging. The lower imaging bandwidth will result in longer acquisition times. Therefore, the need to compromise spatial or temporal resolution is exacerbated to a large extent at lower field strengths. A second issue that is encountered at lower field strengths is the issue of fat suppression. The separation between fat and water peaks, in absolute frequency, decreases as field strength decreases. This makes spectrally selected fat suppression extremely difficult to perform. A third and perhaps most important aspect of low-field-strength imagers with respect to breast MR imaging is the difference in contrast characteristics. The T1 times of tissues tend to decrease as field strength decreases. There is much less change in the relaxivity of gadolinium chelates as field strength decreases. Therefore, the difference in contrast between native tissue and tissue enhanced with a given concentration of gadolinium chelate for a given T1-weighted imaging sequence will be less at the lower field strengths. This has the potential to result in the lack of demonstration of enhancing structures.

Although these issues do not preclude performance of contrast-enhanced breast MR imaging at lower field strengths, they do raise the concern that breast MR imaging performed at a field strength as low as 0.2–0.3 T may not simulate the high-field-strength experience.

As the demand for breast MR imaging increases, dedicated breast MR systems, which would be more accessible and potentially less costly than breast imaging with a standard 1.5-T system, may be needed in the future. However, additional technical improvements in dedicated breast MR imaging systems along with continued clinical investigation to compare the results of imaging at high field strength with those at middle to low field strength are needed before widespread clinical implementation of a dedicated breast MR imaging system.

Breast Coils
Breast MR imaging is typically performed with the patient in the prone position, lying on a platform placed in the MR imager that allows the breast to extend dependently from the patient (11,13–15). Prone patient positioning minimizes the effects of respiratory motion and is preferred to supine imaging, which results in lower image quality.

A dedicated breast surface coil should be used when performing breast MR imaging. Many types of surface coils are available (11,13–15). These include both single-breast and bilateral-breast designs. These coils are also available commercially as single coils or phased arrays. In our experience, the performance of commercially available phased-array bilateral-breast coils is better than that of non–phased-array coils. There are some coils that have been designed in such a way as to provide access to the breast while the patient is lying on the coil (12,13). This provides the opportunity for follow-up MR-guided breast biopsy, if necessary.

Most coil designs rely on a solenoid or solenoid-like coil design that allows imaging of the breast in its natural dependent state. An alternative design consists of mild compression of the breast in the medial to lateral direction between two plates, each of which contains a two-coil phased array (13). This design offers substantial advantages over conventional breast coils. It reduces the dimension of the breast in the medial to lateral direction, borrowing approximately half of the number of sections to image the breast in the sagittal orientation. In addition, this design allows placement of the center of the breast closer to the radio-frequency coil elements, resulting in an increase in signal-to-noise ratio by a factor of approximately 3 over that with a conventional solenoid-like breast coil design. Another is that this design stabilizes the breast and is a natural configuration for MR imaging–guided biopsy.

Use of Paramagnetic Contrast Agents
The cornerstone of breast MR imaging is contrast-enhanced imaging. Most investigators report the use of a contrast agent dose of 0.1 mmol per kilogram of body weight. While the results of one study (16) suggested that the conspicuity of malignant lesions was improved at a gadolinium dose of 0.16 mmol/kg as compared with a dose of 0.1 mmol/kg, there are as yet no large-scale well-controlled studies in which a higher dose of contrast agent has been shown to lead to greater diagnostic accuracy.

The contrast agent is injected intravenously, usually as a bolus, and is followed by a saline flush. To ensure that contrast-enhanced images can be obtained immediately after the contrast agent injection, tuning and gain adjustments should be performed before the injection and should not be readjusted for the remainder of the contrast-enhanced sequence.

Imaging Protocols
Protocols for breast MR imaging vary dramatically (11,15,17). Although the hallmark of breast MR imaging is contrast-enhanced imaging, T2-weighted images can be valuable in establishing the diagnosis of a cyst or fibroadenoma (4,18). Therefore, it is recommended that a fast spin-echo T2-weighted sequence through the breast be acquired routinely prior to administration of contrast material. While in many cases, the T2-weighted image will not be valuable, this will not be known until the contrast-enhanced image is viewed. The T2-weighted sequence is best obtained with fat suppression and a section thickness of approximately 3 mm.

The common element in contrast-enhanced breast MR imaging is acquisition of T1-weighted images before and after intravenous administration of contrast material. With the use of paramagnetic contrast agents and gradient-echo sequences, both two-dimensional and three-dimensional (3D), have largely replaced spin-echo sequences (15,17). Gradient-echo sequences are more time efficient than spin-echo sequences, allowing for faster imaging times. In addition, gradient-echo sequences offer inherently better T1 contrast (with a given number of sections, T1-weighted imaging allows use of much shorter repetition and echo times) and are much more sensitive to the T1-shortening effects of gadolinium chelates than are spin-echo sequences. Although the use of both two-dimensional and 3D imaging sequences has been described, for reliable detection of small (<5-mm) lesions it is generally agreed that high-spatial-resolution 3D techniques should be used to provide large area coverage with thin (3-mm) sections with no intersection gap (11,15,17).

Beyond these general guidelines, a wide variety of acquisition schemes have been proposed. Some investigators (1,2, 5–10,19,20) have developed contrast-enhancement acquisition schemes that emphasize temporal resolution. These dynamic techniques are designed to study enhancement kinetics after contrast agent administration. Dynamic techniques with time resolution varying from a few seconds to a minute have been described. Others (3,4) have stressed the importance of high spatial resolution to detect small lesions and characterize lesion architecture. High-spatial-resolution acquisitions with in-plane spatial resolution as high as 300 µm have been described (4).

Although for many years, the merging of these two schools of thought was difficult, advances in gradient coil technology have reduced the trade-offs between spatial and temporal resolution. These technical advances have led to a convergence in the temporal- and spatial-resolution schools of thought. It is possible to achieve relatively high spatial resolution with a temporal resolution of approximately 1–2 minutes. Today, typical contrast-enhanced breast MR imaging acquisitions have a temporal resolution on the order of 1 minute, with an in-plane pixel size of less than 1 mm and a section thickness of approximately 3 mm or less. With a modern imager with high-performance gradients, a fat-suppressed 256 x 192 x 60-pixel volume can be obtained in approximately 1 minute. This allows reasonably high-resolution images of the breast to be obtained in a time frame that allows one to perform at least a qualitative analysis of enhancement kinetics. From this compromise type of protocol, other protocols can be designed for higher spatial resolution at the expense of temporal resolution or higher temporal resolution at the expense of spatial resolution. This decision is based somewhat on individual preferences for image interpretation with regard to the relative performance of kinetic information versus architectural features.

The use of more novel acquisition sequences such as nonrectilinear k-space sampling and echo-planar imaging may provide the ability to reduce the need for a compromise between spatial and temporal resolutions by improving total acquisition speed (19–22). Currently, these sequences are not commercially available for breast MR imaging. Over time, it is anticipated that these acquisition techniques will provide both high-spatial- and high-temporal-resolution images of the breast and may ultimately dominate MR imaging protocols.

Plane of Acquisition
When imaging a single breast, any acquisition plane can be used, although the sagittal plane appears to be the most popular. This is probably due to the relative ease of correlating a finding identified on a sagittal MR image with a finding on a mediolateral oblique or mediolateral mammographic view. Bilateral examinations are most often performed in the coronal or transverse plane, with a rectangular field of view oriented with the long axis in the medial-to-lateral direction. Imaging in the transverse plane is advantageous, relative to imaging in the coronal plane, because a finding on a transverse MR image can then be correlated with a similarly positioned craniocaudal mammographic view. Newer acquisition schemes that can be used to perform concurrent slab-interleaved 3D acquisitions of both breasts in the sagittal plane have been described (23) and offer potential efficiencies by not imaging the empty space between the breasts.

Fat Suppression
Unlike mammography, in which lesion conspicuity is enhanced against a fatty background, at MR imaging an enhancing lesion may not be discernible because it becomes isointense to fat. Suppression of the fat signal can be attained in two ways: (a) "active" fat suppression, where the fat signal is suppressed prior to the injection of contrast agent, and (b) "passive" fat suppression with postprocessing image subtraction.

Multiple active fat-suppression schemes have been described (11,15). Standard presaturation of fat during every repetition time can be used; however, this results in a dramatic lengthening of examination time over that of the standard non–fat-suppressed imaging protocol. Several more time-efficient alternatives have been described. The rotating delivery of excitation off resonance, or RODEO, sequence uses a spectrally selective excitation pulse to excite only the water in the breast at 3D gradient-echo breast MR imaging (3). Because this radio-frequency pulse is only spectrally selective, the imaging volume is selected by using a coil that has sensitivity restricted to the breast. This is best performed with a coil that both transmits and receives. A robust, time-efficient, fat-suppression technique is the spectrally selective inversion described by Foo et al (24). For this technique, a partial inversion pulse that is spectrally selective for fat is applied intermittently throughout the pulse sequence to suppress the signal from fat. With typical implementations of this technique, fat suppression can be robustly achieved with only a minor increase in acquisition time. This technique can easily be implemented with any coil and any 3D gradient-echo sequence. The major advantages of active fat suppression are insensitivity to patient motion and ease of lesion detection, with enhancing lesions appearing bright against a dark background. The major disadvantage of fat suppression is sensitivity to field inhomogeneity, which may preclude satisfactory fat suppression in some cases.

Fat suppression can also be achieved by means of postprocessing image subtraction (passive fat suppression). Identical imaging parameters before and after contrast agent administration are required. Subtracted images will yield the difference in signal intensity between the unenhanced and enhanced images, directly proportional to the degree of enhancement. Two advantages of image subtraction are minimized acquisition times, because inversion-recovery and saturation pulses are not used, and insensitivity to field inhomogeneity. The major disadvantages of image subtraction are decreased signal-to-noise ratio and sensitivity to patient motion, which can result in misregistration.

	BREAST MR PROTOCOL OF THE HOSPITAL OF THE UNIVERSITY OF PENNSYLVANIA

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
As an example, we present the clinical breast MR imaging protocol ("high-resolution" single-breast examination) used at the Hospital of the University of Pennsylvania (Philadelphia).

Patients undergo imaging in the prone position with a four-coil compression breast array (13). Compression is applied gently so as not to cause patient discomfort. A transverse localizing image is acquired, followed by a sagittal T2-weighted fast spin-echo acquisition with fat suppression. The fast spin-echo acquisition is performed over an 18-cm field of view by using a 256 x 256 matrix and an echo train length of 16. The acquisition bandwidth is 32 kHz. Section thickness is 3 mm with a 1-mm intersection gap.

Nonenhanced and enhanced spoiled gradient-echo (SPGR) images are then obtained. The images are obtained by using a 3D SPGR sequence with intermittent fat-selective partial inversion for fat suppression. Images are obtained over a 512 x 256 x 32 matrix in the sagittal plane. The typical section thickness is 2.0–2.5 mm, depending on the size of the breast. The volume is adjusted so that the 32 sections completely fill the dimensions of the gently compressed breast. The field of view varies from 16 to 18 cm. A repetition time of 9.2 msec and an echo time of 2.1 msec (9.2/2.1) are used. The fat-selective inversion pulse is applied twice every pass through the z axis of k space, or every 16 repetition times. Images are acquired before administration of the contrast agent. Contrast-enhanced imaging is initiated simultaneously with completion of an injection of 20 mL of gadolinium chelate. The injection is then followed by a saline flush, which occurs during contrast-enhanced imaging. The total imaging time is 90 seconds. Two sequential contrast-enhanced studies are obtained.

Potential advantages of this imaging protocol include the compression multicoil array, which permits imaging of the entire breast with a decreased number of sections, and a fat-suppression technique that is time efficient such that images can be obtained with high spatial resolution and relatively high temporal resolution. The major disadvantage of this protocol is that only one breast can be imaged at a time. Ultimately, bilateral-breast imaging will be preferable in many clinical situations, including breast cancer staging and screening of patients at high risk. We are currently investigating an imaging protocol that permits high-resolution fat-suppressed imaging of both breasts in the sagittal plane (23).

	MR IMAGING–GUIDED BIOPSY

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
Similar to the requirement for mammographically and ultrasonographically (US)-guided localization and biopsy systems for obtaining a histologic diagnosis of clinically occult lesions, an MR imaging–guided localization and biopsy system is needed to obtain a histologic diagnosis of lesions detected on MR images that are mammographically, sonographically, and clinically occult (Figs 1, 2). At a May 1, 1997, meeting of the Federal Multi-Agency Consortium on Imaging Technologies to Improve Women’s Health, the lack of MR imaging–guided localization and biopsy technology was cited as one of the major technical challenges for breast MR imaging (25).

View larger version (171K): [in this window] [in a new window] [Download PPT slide]   Figure 1a. MR imaging-guided wire localization in a patient with a palpable mass shown to be carcinoma at fine-needle aspiration biopsy. (a) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR images (21/2.4) reveal not only the mammographically visible and clinically palpable carcinoma (arrow on left) in the upper outer quadrant but also an enhancing mass (arrow on right) in the subareolar portion of the breast. (b) Sagittal fat-suppressed contrast-enhanced gradient-echo MR image (21/2.4) shows imaging-guided wire localization. Arrow = signal void from MR-compatible titanium needle. (c) Mediolateral and (d) craniocaudal mammographic views reveal wire placed with MR imaging guidance. No lesion is seen along the wire. The known cancer (arrow) can be identified in the upper outer quadrant. Excisional biopsy revealed a 1.5-cm invasive ductal carcinoma along the wire and a 1.5-cm invasive ductal carcinoma in the upper outer quadrant.

View larger version (160K): [in this window] [in a new window] [Download PPT slide]   Figure 1b. MR imaging-guided wire localization in a patient with a palpable mass shown to be carcinoma at fine-needle aspiration biopsy. (a) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR images (21/2.4) reveal not only the mammographically visible and clinically palpable carcinoma (arrow on left) in the upper outer quadrant but also an enhancing mass (arrow on right) in the subareolar portion of the breast. (b) Sagittal fat-suppressed contrast-enhanced gradient-echo MR image (21/2.4) shows imaging-guided wire localization. Arrow = signal void from MR-compatible titanium needle . (c) Mediolateral and (d) craniocaudal mammographic views reveal wire placed with MR imaging guidance. No lesion is seen along the wire. The known cancer (arrow) can be identified in the upper outer quadrant. Excisional biopsy revealed a 1.5-cm invasive ductal carcinoma along the wire and a 1.5-cm invasive ductal carcinoma in the upper outer quadrant.

View larger version (102K): [in this window] [in a new window] [Download PPT slide]   Figure 1c. MR imaging-guided wire localization in a patient with a palpable mass shown to be carcinoma at fine-needle aspiration biopsy. (a) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR images (21/2.4) reveal not only the mammographically visible and clinically palpable carcinoma (arrow on left) in the upper outer quadrant but also an enhancing mass (arrow on right) in the subareolar portion of the breast. (b) Sagittal fat-suppressed contrast-enhanced gradient-echo MR image (21/2.4) shows imaging-guided wire localization. Arrow = signal void from MR-compatible titanium needle . (c) Mediolateral and (d) craniocaudal mammographic views reveal wire placed with MR imaging guidance. No lesion is seen along the wire. The known cancer (arrow) can be identified in the upper outer quadrant. Excisional biopsy revealed a 1.5-cm invasive ductal carcinoma along the wire and a 1.5-cm invasive ductal carcinoma in the upper outer quadrant.

View larger version (93K): [in this window] [in a new window] [Download PPT slide]   Figure 1d. MR imaging-guided wire localization in a patient with a palpable mass shown to be carcinoma at fine-needle aspiration biopsy. (a) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR images (21/2.4) reveal not only the mammographically visible and clinically palpable carcinoma (arrow on left) in the upper outer quadrant but also an enhancing mass (arrow on right) in the subareolar portion of the breast. (b) Sagittal fat-suppressed contrast-enhanced gradient-echo MR image (21/2.4) shows imaging-guided wire localization. Arrow = signal void from MR-compatible titanium needle . (c) Mediolateral and (d) craniocaudal mammographic views reveal wire placed with MR imaging guidance. No lesion is seen along the wire. The known cancer (arrow) can be identified in the upper outer quadrant. Excisional biopsy revealed a 1.5-cm invasive ductal carcinoma along the wire and a 1.5-cm invasive ductal carcinoma in the upper outer quadrant.

View larger version (169K): [in this window] [in a new window] [Download PPT slide]   Figure 2a. MR imaging-guided core biopsy in a patient with a palpable mass shown to be invasive ductal carcinoma at US-guided core biopsy. (a) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR images (21.2/2.1) reveal two enhancing lesions, one corresponding to the known cancer (solid arrow) and a second lesion (open arrow) that was occult at mammography and US. (b) MR imaging-guided core biopsy of the additional lesion identified only at MR imaging was performed by using a 14-gauge disposable biopsy gun (Monopty; Bard Urological, Covington, Va). These biopsy results demonstrated invasive ductal carcinoma. Arrow = introducer needle of biopsy gun.

View larger version (82K): [in this window] [in a new window] [Download PPT slide]   Figure 2b. MR imaging-guided core biopsy in a patient with a palpable mass shown to be invasive ductal carcinoma at US-guided core biopsy. (a) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR images (21.2/2.1) reveal two enhancing lesions, one corresponding to the known cancer (solid arrow) and a second lesion (open arrow) that was occult at mammography and US. (b) MR imaging-guided core biopsy of the additional lesion identified only at MR imaging was performed by using a 14-gauge disposable biopsy gun (Monopty; Bard Urological, Covington, Va). These biopsy results demonstrated invasive ductal carcinoma. Arrow = introducer needle of biopsy gun.

View larger version (97K): [in this window] [in a new window] [Download PPT slide]   Figure 3. MR imaging biopsy and localization device. The breast is compressed between a fixed medial plate and a mobile lateral plate. The lateral plate, made of polycarbonate plastic (Lexan; GE Plastics, Pittsfield, Mass), is removable and can be sterilized. Copper sulfate reference markers (arrows) are placed arbitrarily into holes in the plate.

MR imaging–compatible needles are available from many manufacturers. There are still multiple problems associated with MR needles, such as extensive artifact on gradient-echo images and poor performance of core biopsy guns. Continued development of higher quality needles and core biopsy guns are important to the further development of MR imaging–guided breast biopsy.

There are several limitations of MR imaging–guided localization. One limitation with many systems is access to only the lateral side of the breast. This often will not be the shortest path to the lesion and could result in surgical removal of additional breast tissue and a potentially suboptimal cosmetic result. A system that would permit easy access to at least the medial side of the breast and potentially to any part of the breast would be advantageous. A second limitation of MR imaging–guided localization is the inability to verify lesion removal in many cases (34). In mammography, imaging of the specimen is routinely performed to document lesion removal. In contrast, MR imaging of the specimen is not feasible, since most lesions are visualized only transiently after contrast agent administration, and the specimen is avascular. A tissue marker such as a titanium clip that could be placed into the lesion at the time of MR-guided localization is being investigated. This would allow documentation of lesion removal. Both of these limitations could be overcome with an MR imaging–guided core biopsy system. The results of a preliminary investigation (35) with such systems, including a vacuum-assisted device, have been promising.

Up to now, MR imaging–guided localization and biopsy systems have been available almost exclusively at research centers. It is only recently that such systems have become commercially available. Continued technical developments in both localization and biopsy systems will be critical to the ultimate success of MR imaging guidance for successful biopsy of cancers that can be identified only at MR imaging.

	IMAGE INTERPRETATION: WHAT CONSTITUTES CLINICALLY IMPORTANT ENHANCEMENT?

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
In addition to the many technical factors involved in performing breast MR imaging, another potential barrier to the widespread adoption of MR as a breast imaging method is the absence of guidelines for interpreting MR studies. After intravenous administration of a contrast agent, it may appear that enhancing "lesions" are present throughout the breast. How are the potentially clinically important lesions identified?

At present, there are no standard interpretation criteria for evaluating breast MR studies. There are probably as many definitions of suggestive enhancement as there are investigators. Each investigator has chosen a specific definition of suggestive enhancement that, on the basis of their experience, yields the highest sensitivity and specificity for the detection of breast cancer. This, in turn, is reflective of multiple factors, including obtainable temporal and spatial resolution, patient population, and histologic features of lesions, as well as investigator preferences.

There have been two major approaches to image interpretation: (a) evaluation of enhancement kinetics following contrast agent administration and (b) evaluation of lesion morphology. The results of early studies (1,2) in Europe conducted after the introduction of intravenous gadolinium chelates generated considerable enthusiasm for a quantitative assessment of contrast enhancement. The authors of these studies demonstrated that malignant lesions consistently enhance after the administration of gadolinium chelate and tend to enhance earlier and to a greater degree than do benign lesions (1,2). On the basis of the promising results of these studies, it was suggested that enhancement kinetics could be used to identify suggestively enhancing lesions and differentiate these from benign enhancement. Several empiric measurements of enhancement have been used, including the maximum rate of enhancement (slope of enhancement uptake) and the increase in signal intensity after contrast agent administration (1,2,5–10,19,20,36–40).

Recommendations for the interval at which the measurements should be performed and the optimal threshold level above which enhancement should be considered suggestive have varied widely. Kaiser and Zeitler (2) classified a lesion as suspicious if the lesion demonstrated a 100% increase in signal intensity within the first 2 minutes after contrast agent injection (2). Heywang-Kobrunner (1) considered enhancement above 300 normalized units to be important. Gribbestad et al (6) defined important enhancement as a greater than 70% increase in signal intensity after 60 seconds. Gilles et al (7) defined enhancement concomitant with early vascular enhancement as suggestive. Boetes et al (5) defined enhancement within 11.5 seconds after aortic enhancement as suggestive. Kuhl et al (39,40) classified a lesion as suspicious if it demonstrated a greater than 60% increase in signal intensity that was apparent on the first contrast-enhanced image (40 seconds). Stomper et al (41) defined enhancement that is two or more times greater than the unenhanced signal intensity as suggestive. Quantitative methods have also included sophisticated physiologic modeling of uptake and washout of contrast agents (4,22,42,43).

In contrast to these quantitative methods, in which one or more kinetic measurements are used, a qualitative method has been described for evaluation of the overall shape of the enhancement curve (39,40). This type of approach permits visual inspection of the enhancement curve as an alternative to complex mathematical models or the need to quantify the amount or rate of absolute enhancement. Three types of time-intensity curves have been described: type I (steady enhancement), where a persistent increase in signal intensity is present beyond 2 minutes after contrast agent injection; type II (plateau), where the maximum signal intensity is achieved in the first 2 minutes and then remains fairly constant; and type III (washout), where the maximum signal intensity is achieved in the first 2 minutes and then decreases over time. It has been reported that benign lesions tend to exhibit a type I curve, and malignant lesions tend to exhibit a type III curve. It has also been reported (39,40) that evaluation of these curves results in improved specificity and accuracy, as compared with the evaluation of enhancement rates.

For all of these approaches in which enhancement kinetics are evaluated—both quantitative and qualitative methods—accurate placement of a region of interest over the area(s) of most rapid and intense enhancement is critical. Statistically significant interobserver variability and bias in placement of the region of interest have been reported, although this variability can be improved when a semiautomated method with parametric images is used (44). In addition, placement of a region of interest and generation of a time-intensity curve for both ductal enhancement (ie, seen in ductal carcinoma in situ [DCIS]) and regional enhancement (ie, seen in both benign and malignant lesions) may not be as accurate as those for solid masses.

The second major approach to image interpretation has been the evaluation of lesion morphology. Although the authors of early reports were optimistic that the evaluation of enhancement kinetic measurements could be used to differentiate malignant from benign lesions, results from later studies demonstrated considerable overlap in the enhancement characteristics of malignant and benign lesions, which is likely due to histologic variability (4,38,41,45,46). On the basis of this overlap, it was suggested (4) that architectural features identified on high-spatial-resolution images could be used to characterize lesions as likely malignant or likely benign (Fig 4). Architectural features that have been reported as suggestive of malignancy include a mass with irregular or spiculated borders, a mass with peripheral enhancement, and ductal enhancement (4,7,45–52). Architectural features that have been reported suggestive of a benign process include a mass with smooth or lobulated borders, a mass demonstrating no contrast enhancement, a mass with nonenhancing internal septa, and patchy parenchymal enhancement (3,4,45,53). A decision tree incorporating several architectural features has been described (54). Because reader variability remains a concern, an imaging lexicon, similar to the Breast Imaging Reporting and Data System, or BI-RADS, lexicon used in mammography in which the architectural features are defined and illustrated is needed. Development of such a lexicon is in progress (55).

View larger version (168K): [in this window] [in a new window] [Download PPT slide]   Figure 4a. Lesion morphology. (a) Linear enhancement of DCIS. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) reveals an area of linear enhancement (arrows) in a patient with bloody nipple discharge. MR imaging-guided wire localization revealed DCIS. (b) Peripheral enhancement in invasive carcinoma. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.2) in a patient with a palpable mass reveals a lesion (arrows) that is enhancing around the periphery. Invasive ductal carcinoma was found at excisional biopsy. (c) Internal septa in fibroadenoma. Sagittal fat-suppressed T2-weighted fast spin-echo MR image (4,000/120) in a patient with a developing mass identified at mammography reveals an enhancing lesion (arrow) containing nonenhancing septa. Fibroadenoma was found at excisional biopsy. (d) Regional enhancement. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.2) in a patient with newly diagnosed invasive breast cancer identified at mammography and physical examination reveals an area of regional enhancement (arrows) that was adjacent to the known breast cancer. At excisional biopsy, extensive DCIS was found adjacent to the known invasive breast cancer.

View larger version (152K): [in this window] [in a new window] [Download PPT slide]   Figure 4b. Lesion morphology. (a) Linear enhancement of DCIS. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) reveals an area of linear enhancement (arrows) in a patient with bloody nipple discharge. MR imaging-guided wire localization revealed DCIS. (b) Peripheral enhancement in invasive carcinoma. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.2) in a patient with a palpable mass reveals a lesion (arrows) that is enhancing around the periphery. Invasive ductal carcinoma was found at excisional biopsy. (c) Internal septa in fibroadenoma. Sagittal fat-suppressed T2-weighted fast spin-echo MR image (4,000/120) in a patient with a developing mass identified at mammography reveals an enhancing lesion (arrow) containing nonenhancing septa. Fibroadenoma was found at excisional biopsy. (d) Regional enhancement. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.2) in a patient with newly diagnosed invasive breast cancer identified at mammography and physical examination reveals an area of regional enhancement (arrows) that was adjacent to the known breast cancer. At excisional biopsy, extensive DCIS was found adjacent to the known invasive breast cancer.

View larger version (120K): [in this window] [in a new window] [Download PPT slide]   Figure 4c. Lesion morphology. (a) Linear enhancement of DCIS. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) reveals an area of linear enhancement (arrows) in a patient with bloody nipple discharge. MR imaging-guided wire localization revealed DCIS. (b) Peripheral enhancement in invasive carcinoma. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.2) in a patient with a palpable mass reveals a lesion (arrows) that is enhancing around the periphery. Invasive ductal carcinoma was found at excisional biopsy. (c) Internal septa in fibroadenoma. Sagittal fat-suppressed T2-weighted fast spin-echo MR image (4,000/120) in a patient with a developing mass identified at mammography reveals an enhancing lesion (arrow) containing nonenhancing septa. Fibroadenoma was found at excisional biopsy. (d) Regional enhancement. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.2) in a patient with newly diagnosed invasive breast cancer identified at mammography and physical examination reveals an area of regional enhancement (arrows) that was adjacent to the known breast cancer. At excisional biopsy, extensive DCIS was found adjacent to the known invasive breast cancer.

View larger version (128K): [in this window] [in a new window] [Download PPT slide]   Figure 4d. Lesion morphology. (a) Linear enhancement of DCIS. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) reveals an area of linear enhancement (arrows) in a patient with bloody nipple discharge. MR imaging-guided wire localization revealed DCIS. (b) Peripheral enhancement in invasive carcinoma. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.2) in a patient with a palpable mass reveals a lesion (arrows) that is enhancing around the periphery. Invasive ductal carcinoma was found at excisional biopsy. (c) Internal septa in fibroadenoma. Sagittal fat-suppressed T2-weighted fast spin-echo MR image (4,000/120) in a patient with a developing mass identified at mammography reveals an enhancing lesion (arrow) containing nonenhancing septa. Fibroadenoma was found at excisional biopsy. (d) Regional enhancement. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.2) in a patient with newly diagnosed invasive breast cancer identified at mammography and physical examination reveals an area of regional enhancement (arrows) that was adjacent to the known breast cancer. At excisional biopsy, extensive DCIS was found adjacent to the known invasive breast cancer.

Although individual investigators have set criteria for what constitutes a potentially malignant enhancing lesion, one must remember that these investigators used a wide variety of imaging sequences. The reported results with one technique will not necessarily be transferable to other MR techniques, and no single set of interpretation criteria are uniformly accepted at the present time. There clearly are many possible methods for interpreting breast MR studies. Which method(s) is optimal remains to be defined. As long as there continues to be wide variability in breast MR imaging systems, including variable magnetic field strengths, available pulse sequences, and variable surface coils, it may be that the optimal interpretation method will differ on the basis of available hardware and software. It may also be that the interpretation method will vary on the basis of the indication for the MR examination. With continued technical improvements, the potential exists for imaging with both high temporal and spatial resolution, without substantial compromise on either side, such that optimized kinetic and morphologic information can be obtained in one study.

Despite the present lack of consensus on how best to obtain breast MR images and in the absence of a unifying scheme for image interpretation, there is greater than ever agreement among investigators in terms of what is regarded as crucial for breast MR technique and also what criteria should be applied for lesion diagnosis. MR imaging is a robust technique that offers many ways to detect and classify breast lesions. Despite the fact that so many fundamentally different approaches have been taken and although so many different concepts of what constitutes clinically important enhancement have been presented, there is still almost universal agreement that breast MR imaging is an extremely sensitive imaging technique for the detection of breast cancer. Owing to the wide variety of imaging parameters and diagnostic criteria provided by breast MR imaging, standardization of technique and interpretation may take longer than with other breast imaging techniques.

	POTENTIAL CLINICAL APPLICATIONS

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
There is a rapidly growing clinical demand for the use of breast MR imaging to evaluate patients with a breast-related problem that may not be adequately addressed with conventional imaging methods. While, at the present time, the clinical indications for MR imaging of breast as a method to help detect and diagnose breast cancer remain to be defined, several potential clinical applications have emerged on the basis of the results of clinical investigation thus far.

	LESION DETECTION

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
Can MR imaging help decrease the number of breast biopsies performed for mammographically or clinically demonstrated abnormalities? One of the major limitations of mammography is overlap in the appearances of benign and malignant lesions. Approximately 75% of mammographically detected suspected or indeterminate lesions will prove to be benign at biopsy (57). A similar limitation of physical examination also results in the biopsy of many palpable benign lesions. An imaging method that could help reduce the number of breast biopsies performed for benign lesions is desirable, assuming that the improved specificity will not be at the cost of reduced sensitivity for the detection of cancer. Because investigators of breast MR imaging have reported higher sensitivities and specificities for MR imaging compared with those for mammography, it has been suggested that MR imaging could be used to further characterize indeterminate lesions detected at mammography, US, or physical examination. A lesion that appears unequivocally benign at MR imaging could then be followed rather than excised. The addition of MR imaging could, therefore, result in a decrease the number of biopsies performed for benign causes.

How has MR imaging performed in this role? It is not surprising, based on the plethora of potential interpretation methods, that comparison of specificity data reported in various series is difficult. Review of the literature yields a wide range of results, with reported specificities ranging from 37% to 97% (1–3,5,7, 8,19,36,39,51,58–60). This wide range is probably the result of multiple factors, including patient selection, patient age, lesion histologic characteristics, and variability in interpretation criteria.

The potentially limited specificity of MR imaging has been attributed to the fact that, in addition to cancer, many benign lesions as well as presumably normal breast tissue may enhance after administration of contrast material. Enhancement has been seen in many benign lesions, including fibroadenoma, proliferative and nonproliferative fibrocystic change, and mastitis, as well as increased-risk lesions such as radial scars, atypical ductal hyperplasia, and lobular carcinoma in situ (3,4,7,8,18,37,41,58,59). In addition, presumably normal breast tissue may enhance, and this has been shown to vary in degree at different times of the menstrual cycle (39,61). Enhancement of benign lesions along with presumably normal breast tissue has demonstrated overlap with enhancement of malignant lesions, both in terms of kinetic measurements and morphologic appearances, which precludes complete differentiation of benign from malignant lesions.

The primary benefit of a noninvasive test such as MR imaging undertaken prior to tissue diagnosis (ie, with core biopsy or excisional biopsy) is that it can be used to determine which lesions are likely to be benign, so that mammographic or clinical follow-up could be used in place of tissue diagnosis. When a test is used in this capacity, it must be sufficiently sensitive that the negative predictive value is very high (approaching 100%) without sacrificing specificity. In addition, if these goals are met, it will also have to be determined whether the use of the test is cost-effective. Does MR imaging meet these requirements? Can MR imaging be used to determine which lesions are likely benign and do not require tissue diagnosis, and will MR imaging be a cost-effective technology? The overlap in enhancement characteristics and morphologic appearances of benign and malignant lesions remains a problem and may limit the use of MR imaging in this capacity. If, however, after a large number of patients are examined, certain MR features are shown to be close to 100% reliable for diagnosis of lesions as benign and mammographic and clinical findings do not suggest that the lesion is highly likely to be malignant, then MR imaging findings could be used to support the use of mammographic or clinical follow-up rather than tissue diagnosis.

In terms of cost-effectiveness, MR imaging must compete with percutaneous breast biopsy. Stereotactic and US-guided biopsy have demonstrated high sensitivity and specificity, comparable to those of excisional biopsy, at approximately one-fourth the cost excisional biopsy (62–67). With the increasing availability of percutaneous biopsy, MR imaging with a less than perfect specificity and sensitivity may not prove to be a cost-effective method to help differentiate benign from malignant lesions. However, cost-effectiveness studies that take into account not only objective costs but also subjective costs (eg, patient preferences) are needed to determine whether follow-up based on benign findings at MR imaging is optimal in comparison with proceeding either to core biopsy or excisional biopsy. For a woman who does not want to undergo breast biopsy (either excisional or percutaneous), who has a history of multiple biopsy-proved fibroadenomas, and who develops a new palpable mass, MR imaging might prove to be clinically useful if the lesion can reliably be shown to be benign. In addition, in patients found to have breast cancer, while this diagnosis can be established with percutaneous core biopsy, MR imaging may be still be advantageous because it can be used not only to characterize the lesion in question but also to evaluate the remainder of the breast, potentially leading to identification of unsuspected multifocal disease. Additional clinical studies, including cost-effective analyses, to directly compare MR imaging and imaging-guided biopsy are needed to address these issues.

	BREAST CANCER DETECTION, DIAGNOSIS, AND STAGING

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
Although mammography remains the primary imaging modality used in the detection of early breast cancer, the frequency of false-negative results is estimated to be 5%–15% (68). The inability to detect breast cancer at mammography is often due to obscuration of the tumor by superimposed fibroglandular tissue. This imperfect sensitivity of mammography has led to the use of adjunctive imaging methods, including MR imaging. Although MR imaging has demonstrated variable specificity, the reported (2–7) sensitivity of this modality for the demonstration of invasive breast cancer has approached 100% in several series. The invasive cancers in these studies have predominantly been invasive ductal carcinoma. In terms of the sensitivity of MR imaging for detection of invasive lobular carcinoma, relatively little has been published (69). There have been reports of false-negative MR results in cases of invasive lobular cancer (7,69,70), although authors of recent reports suggest that MR imaging may be sensitive for the demonstration of this cancer (69,71). In contrast to high sensitivity of MR imaging for the demonstration of invasive cancer reported in multiple series, the reported (51,52,72,73) sensitivity of MR imaging for the demonstration of DCIS has been variable, ranging from 40% to 100%. This wide range probably reflects small numbers of cases, variable imaging techniques, and the histologic variability (including differences in degree of angiogenesis) of DCIS (74–76). There are, however, reports (31,47,51) of mammographically and clinically occult DCIS that was demonstrated at MR imaging.

On the basis of the promising results of these studies, it has been proposed that MR imaging, with its high sensitivity for the demonstration of invasive breast cancer, could be used as an adjunctive imaging modality when the results of conventional imaging and clinical examinations are equivocal and for breast cancer staging in patients with newly diagnosed disease.

	PROBLEM SOLVING: IS CANCER PRESENT?

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
There are reports (77,78) that MR imaging can be used as a problem-solving tool in cases where a suggestive lesion is identified on only one mammographic view and in cases of equivocal mammographic or physical examination findings (Fig 5). MR imaging may also play a problem-solving role in the evaluation of patients who have undergone breast conservation therapy for breast cancer in whom equivocal changes are identified at mammography or physical examination. For these patients, posttreatment follow-up can sometimes be difficult, because posttreatment changes can mimic and obscure recurrent disease.

View larger version (186K): [in this window] [in a new window] [Download PPT slide]   Figure 5a. MR imaging for problem solving. Images in a woman with two abnormalities identified at mammography, each seen on only one mammographic view. (a) Spot mediolateral oblique magnification mammogram demonstrates a cluster of calcifications (arrow). (b) Mediolateral mammographic view obtained during diagnostic work-up shows an area of possible architectural distortion (arrows), which was visible only on this view. No definite lesion was identified at US (not shown). (c) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) reveals an enhancing spiculated mass (bottom arrow) in the central lateral portion of the breast and a second enhancing lesion (top arrow) in the superior lateral portion. MR imaging-guided wire localization was performed for both lesions. Mammographic specimen radiography (not shown) demonstrated the calcifications in the superior lateral specimen and architectural distortion in the central lateral specimen. Two infiltrating ductal carcinomas were identified at histopathologic examination. The patient subsequently underwent mastectomy.

View larger version (149K): [in this window] [in a new window] [Download PPT slide]   Figure 5b. MR imaging for problem solving. Images in a woman with two abnormalities identified at mammography, each seen on only one mammographic view. (a) Spot mediolateral oblique magnification mammogram demonstrates a cluster of calcifications (arrow). (b) Mediolateral mammographic view obtained during diagnostic work-up shows an area of possible architectural distortion (arrows), which was visible only on this view. No definite lesion was identified at US (not shown). (c) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) reveals an enhancing spiculated mass (bottom arrow) in the central lateral portion of the breast and a second enhancing lesion (top arrow) in the superior lateral portion. MR imaging-guided wire localization was performed for both lesions. Mammographic specimen radiography (not shown) demonstrated the calcifications in the superior lateral specimen and architectural distortion in the central lateral specimen. Two infiltrating ductal carcinomas were identified at histopathologic examination. The patient subsequently underwent mastectomy.

View larger version (76K): [in this window] [in a new window] [Download PPT slide]   Figure 5c. MR imaging for problem solving. Images in a woman with two abnormalities identified at mammography, each seen on only one mammographic view. (a) Spot mediolateral oblique magnification mammogram demonstrates a cluster of calcifications (arrow). (b) Mediolateral mammographic view obtained during diagnostic work-up shows an area of possible architectural distortion (arrows), which was visible only on this view. No definite lesion was identified at US (not shown). (c) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) reveals an enhancing spiculated mass (bottom arrow) in the central lateral portion of the breast and a second enhancing lesion (top arrow) in the superior lateral portion. MR imaging-guided wire localization was performed for both lesions. Mammographic specimen radiography (not shown) demonstrated the calcifications in the superior lateral specimen and architectural distortion in the central lateral specimen. Two infiltrating ductal carcinomas were identified at histopathologic examination. The patient subsequently underwent mastectomy.

View larger version (88K): [in this window] [in a new window] [Download PPT slide]   Figure 6. False-positive MR image obtained after breast conservation therapy. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR image (9.2/2.1) in a patient enrolled in a research protocol to evaluate resolution of radiation-induced changes reveals an area of enhancement (arrow) in the lumpectomy bed; this enhancement developed 36 months after treatment. MR imaging-guided wire localization revealed fat necrosis.

First, in controlled research settings, it has been demonstrated that MR imaging can help reliably identify invasive cancer, and, based on results of several studies, it has been suggested that a negative MR image virtually excludes the presence of invasive cancer (42). However, as noted earlier, there have been many reports (3–5,7,11) of false-negative MR studies, including cases of invasive ductal cancer, invasive lobular cancer, and DCIS. As is true with a negative mammogram or a negative US study in a patient with a suggestive palpable abnormality, a negative MR study should not preclude biopsy of a suggestive mammographic, US, or palpable abnormality (Fig 7). Second, MR imaging should not be used in lieu of high-quality mammographic work-up for equivocal findings identified at screening. In addition, MR imaging should not be used in place of breast US. Many equivocal mammographic findings are well evaluated with breast US, which is more readily available and less costly than MR imaging. Finally, it is critical that MR imaging findings be correlated with mammographic findings to ensure that a lesion identified on MR images corresponds to that identified on mammograms. If the MR study is negative, the recommendation must be based on mammographic, US, or clinical findings. A single recommendation based on results of both the conventional work-up and the MR study should be given.

View larger version (200K): [in this window] [in a new window] [Download PPT slide]   Figure 7a. False-negative MR imaging study. Images in a patient with two palpable masses. (a) US study demonstrated two lobulated hypoechoic masses with indistinct borders; one of these masses (arrows) is illustrated on this image. Owing to the multiplicity of the masses, MR imaging was requested for further characterization of the lesions. (b) Sagittal T2-weighted fast spin-echo MR image (5,000/120) reveals two dominant high-signal-intensity masses. (c) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) reveals minimal enhancement around the masses (arrows). The MR study was interpreted as demonstrating multiple clusters of cysts. MR imaging findings, however, were inconsistent with US findings that suggested that the masses were solid. Excisional biopsy revealed multifocal colloid carcinoma.

View larger version (74K): [in this window] [in a new window] [Download PPT slide]   Figure 7b. False-negative MR imaging study. Images in a patient with two palpable masses. (a) US study demonstrated two lobulated hypoechoic masses with indistinct borders; one of these masses (arrows) is illustrated on this image. Owing to the multiplicity of the masses, MR imaging was requested for further characterization of the lesions. (b) Sagittal T2-weighted fast spin-echo MR image (5,000/120) reveals two dominant high-signal-intensity masses. (c) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) reveals minimal enhancement around the masses (arrows). The MR study was interpreted as demonstrating multiple clusters of cysts. MR imaging findings, however, were inconsistent with US findings that suggested that the masses were solid. Excisional biopsy revealed multifocal colloid carcinoma.

View larger version (112K): [in this window] [in a new window] [Download PPT slide]   Figure 7c. False-negative MR imaging study. Images in a patient with two palpable masses. (a) US study demonstrated two lobulated hypoechoic masses with indistinct borders; one of these masses (arrows) is illustrated on this image. Owing to the multiplicity of the masses, MR imaging was requested for further characterization of the lesions. (b) Sagittal T2-weighted fast spin-echo MR image (5,000/120) reveals two dominant high-signal-intensity masses. (c) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) reveals minimal enhancement around the masses (arrows). The MR study was interpreted as demonstrating multiple clusters of cysts. MR imaging findings, however, were inconsistent with US findings that suggested that the masses were solid. Excisional biopsy revealed multifocal colloid carcinoma.

	BREAST CANCER STAGING

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

View larger version (186K): [in this window] [in a new window] [Download PPT slide]   Figure 8a. MR imaging for breast cancer staging. Images in a patient after stereotactic core-needle biopsy for mammographically identified microcalcifications. Histopathologic examination revealed DCIS. (a) Mediolateral mammographic view demonstrates a core biopsy clip (arrow) in the central portion of the breast. No residual microcalcifications were identified. (b) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) reveals a 1.5-cm enhancing spiculated mass (arrowhead) in the superior portion of the breast several centimeters superior to the core biopsy clip (arrow). The mass was then identified at US (not shown), and US-guided wire localization and excisional biopsy revealed invasive ductal carcinoma. Mammography-guided wire localization and excisional biopsy of the core biopsy clip revealed residual DCIS. The patient subsequently underwent mastectomy.

View larger version (165K): [in this window] [in a new window] [Download PPT slide]   Figure 8b. MR imaging for breast cancer staging. Images in a patient after stereotactic core-needle biopsy for mammographically identified microcalcifications. Histopathologic examination revealed DCIS. (a) Mediolateral mammographic view demonstrates a core biopsy clip (arrow) in the central portion of the breast. No residual microcalcifications were identified. (b) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) reveals a 1.5-cm enhancing spiculated mass (arrowhead) in the superior portion of the breast several centimeters superior to the core biopsy clip (arrow). The mass was then identified at US (not shown), and US-guided wire localization and excisional biopsy revealed invasive ductal carcinoma. Mammography-guided wire localization and excisional biopsy of the core biopsy clip revealed residual DCIS. The patient subsequently underwent mastectomy.

View larger version (153K): [in this window] [in a new window] [Download PPT slide]   Figure 9. MR imaging (sagittal fat-suppressed contrast-enhanced 3D fast SPGR [9.2/2.1]) for breast cancer staging after excisional biopsy with positive margins of resection. Left: A 7-mm enhancing lesion (arrow) is located 3 cm inferior to the postoperative seroma. Right: MR imaging-guided wire localization (arrow) and excisional biopsy were performed prior to repeat excision. Invasive ductal carcinoma was found along the localizing wire. The surgeon noted that the MR-localized lesion would not have been contained within the standard re-excision specimen.

	PITFALLS OF MR IMAGING FOR BREAST CANCER STAGING

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

View larger version (104K): [in this window] [in a new window] [Download PPT slide]   Figure 10. Pitfall of MR imaging staging of breast cancer: false-positive enhancement in a patient with multifocal invasive lobular carcinoma in the left breast. MR screening of the contralateral (ie, right) breast was requested. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) of the right breast shows multifocal areas of enhancement, which were interpreted as suggestive of carcinoma; MR-guided wire localization for sampling was recommended. The patient opted to undergo bilateral mastectomies. Histopathologic review of the right mastectomy specimen revealed no breast carcinoma.

	QUESTIONS SURROUNDING MR IMAGING BREAST CANCER STAGING

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
There are a multitude of questions related to staging of breast cancer with MR imaging. What is the clinical importance of additional foci of carcinoma detected only with MR imaging? Can this disease, especially when it is found to be DCIS, be effectively treated with radiation therapy? When multifocal cancer is identified on MR images, is mastectomy required? If all identified foci can be successfully excised with negative margins, can the patient be treated with breast conservation? Will the use of MR imaging result in an increase in unnecessary mastectomies? Which patients are at risk for multifocal or extensive cancer that would benefit most from MR imaging (palpable cancers, patients with dense breasts)? Continued clinical investigation, including prospective clinical trials, is needed to address these issues.

	BREAST CANCER STAGING WITH MR IMAGING: SPECIAL CONSIDERATIONS

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
Axillary Node Metastases and Unknown Primary Malignancy
Breast cancer can manifest as isolated axillary metastases, with no radiographic or clinical evidence of a primary tumor within the breast. The incidence of an axillary lymph node manifestation from an occult primary breast cancer is low, with rates ranging from 0.3% to 0.8% of all patients with carcinoma of the breast at the time of presentation (97). The most commonly used treatment is mastectomy and axillary dissection, although in approximately one-third of cases, no tumor is found in the mastectomy specimen. The ability to detect a primary breast cancer at mammography and define its extent in these patients has been disappointing. The reported (97) frequency of finding an occult breast cancer at mammography has ranged from 0% to 56%. Reported (98–101) rates of primary breast cancer detected at MR imaging in patients with axillary node metastases who present with negative mammographic and physical examination findings have ranged from 75% to 86% (Fig 11).

View larger version (165K): [in this window] [in a new window] [Download PPT slide]   Figure 11a. MR imaging in patients with axillary node malignancy and unknown primary tumor site. (a) Localized tumor. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) in a patient with malignant axillary adenopathy and a negative mammogram reveals a focal area of enhancement (arrows) in the subareolar portion of the breast. Biopsy revealed invasive ductal carcinoma. The patient was treated with lumpectomy and radiation therapy. (b) Diffuse tumor. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) in a patient with malignant axillary adenopathy and a negative mammogram reveals multifocal areas of enhancement, which were present throughout the breast. At mastectomy, multifocal invasive lobular carcinoma was found.

View larger version (116K): [in this window] [in a new window] [Download PPT slide]   Figure 11b. MR imaging in patients with axillary node malignancy and unknown primary tumor site. (a) Localized tumor. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) in a patient with malignant axillary adenopathy and a negative mammogram reveals a focal area of enhancement (arrows) in the subareolar portion of the breast. Biopsy revealed invasive ductal carcinoma. The patient was treated with lumpectomy and radiation therapy. (b) Diffuse tumor. Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.2/2.1) in a patient with malignant axillary adenopathy and a negative mammogram reveals multifocal areas of enhancement, which were present throughout the breast. At mastectomy, multifocal invasive lobular carcinoma was found.

Locally Advanced Breast Cancer: MR Imaging for Monitoring Response to Chemotherapy
Patients with locally advanced (stage III) breast cancer undergo combined multimodality treatment beginning with chemotherapy followed by surgery, additional chemotherapy, and radiation therapy in various sequences (102,103). The presence of residual tumor following chemotherapy can be used as an index of response to drug treatment and is a critical prognostic factor for disease-free and overall survival. The clinical and mammographic detection of tumor response, however, can be impaired by chemotherapy-induced fibrosis.

Results of preliminary investigations (104,105) in this patient population have demonstrated that MR imaging appears to be a highly sensitive method for detecting tumor response to chemotherapy (Fig 12). It appears that MR imaging can provide evidence of response to therapy by showing a decrease in contrast enhancement of the tumor even before any change in tumor size can be detected (104,105). However, the effect of chemotherapy on the dynamics of contrast agent uptake in breast cancer remains unclear. Initial experience (105) has suggested that the sensitivity of MR imaging for detecting residual cancer may be reduced by the effects of chemotherapy. Additional studies are needed to assess the influence of chemotherapy on MR imaging sensitivity and to determine whether MR findings can be used to guide treatment planning and help predict prognosis in this group of patients.

View larger version (213K): [in this window] [in a new window] [Download PPT slide]   Figure 12a. MR imaging during chemotherapy in a patient who underwent mastectomy of the right breast with malignant axillary adenopathy on the left side. (a) Initial sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR images (9.3/2.2) reveal multiple enhancing lesions (arrows) that are scattered in the breast. The largest (1-cm) lesion, in the upper outer quadrant, was subsequently identified at US and core biopsy as invasive ductal carcinoma. (b) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.3/2.1) obtained 3 months later, following chemotherapy, reveals one residual lesion (arrow). At mastectomy, a 4-mm invasive ductal carcinoma was found that corresponded to the lesion identified at MR imaging.

View larger version (154K): [in this window] [in a new window] [Download PPT slide]   Figure 12b. MR imaging during chemotherapy in a patient who underwent mastectomy of the right breast with malignant axillary adenopathy on the left side. (a) Initial sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR images (9.3/2.2) reveal multiple enhancing lesions (arrows) that are scattered in the breast. The largest (1-cm) lesion, in the upper outer quadrant, was subsequently identified at US and core biopsy as invasive ductal carcinoma. (b) Sagittal fat-suppressed contrast-enhanced 3D fast SPGR MR image (9.3/2.1) obtained 3 months later, following chemotherapy, reveals one residual lesion (arrow). At mastectomy, a 4-mm invasive ductal carcinoma was found that corresponded to the lesion identified at MR imaging.

	MR IMAGING–GUIDED TREATMENT OF BREAST CANCER

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

Diagnostic imaging techniques that are being investigated as modalities to provide guidance for these minimally invasive therapies include US, computed tomography (CT), and MR imaging. Of these techniques, contrast-enhanced MR imaging appears to be the most sensitive method for breast cancer detection and staging. MR imaging also offers other advantages: It is less operator dependent and offers better soft-tissue contrast resolution than US; in addition, preliminary experience suggests that MR imaging may be more accurate than CT in depicting tumor response to treatment.

Currently, only the focused ultrasound system has been incorporated with an MR imager. Research groups are also evaluating a prototype MR imaging–guided ultrasound device manufactured by GE Medical Systems. The system is currently being tested in the treatment of fibroadenomas.

Of these minimally invasive therapies, detailed clinical and experimental data are available only for interstitial laser photocoagulation of breast tumors. Mumtaz et al (106), in a study of interstitial laser photocoagulation in 20 patients with breast cancer, reported that delayed (24–96 hours after treatment) contrast-enhanced MR imaging demonstrated laser-induced necrosis as a zone of nonenhancement within the residual enhancing tumor, with correlation coefficients (MR imaging findings vs histopathologic findings) for laser-burn diameter and residual tumor of 0.80 and 0.86, respectively. Clinical investigation of MR imaging–guided breast tumor ablation continues.

	BREAST CANCER SCREENING

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
While mammography is the only imaging modality with proved effectiveness for the detection of early clinically occult breast cancer and remains the primary imaging modality for breast cancer screening, potential limitations in sensitivity have stimulated exploration into adjunctive imaging modalities for breast cancer screening, including breast MR imaging. Although, in the diagnostic setting, MR imaging has demonstrated high sensitivity for the detection of invasive breast cancer and probably for DCIS as well, little is known about the efficacy of MR imaging as a method to screen for breast cancer. There are now several ongoing studies in which MR imaging is being evaluated for breast cancer screening in patient populations at increased risk for the development of breast cancer, including patients with newly diagnosed breast cancer and those believed to be at high risk for the development of breast cancer (Fig 13).

View larger version (159K): [in this window] [in a new window] [Download PPT slide]   Figure 13a. MR imaging for breast cancer screening in patients at high risk. Images in a patient with a family history of breast cancer. (a) Mediolateral oblique mammographic view reveals dense breast tissue with no suggestive findings. (b) Sagittal computer-subtracted fat-suppressed contrast-enhanced 3D fast SPGR MR images (18.2/2.1) reveal two 7-mm enhancing lesions (arrows) in the superior lateral aspect of the left breast. Follow-up US (not shown) demonstrated two hypoechoic lesions in the upper outer quadrant that corresponded in size and location to the MR imaging-demonstrated lesions. US-guided fine-needle aspiration biopsy revealed adenocarcinoma from one lesion and atypia from the second lesion. The patient underwent bilateral mastectomies, and two invasive carcinomas (1.1-cm invasive ductal carcinoma and 3-mm invasive tubular carcinoma) were identified.

View larger version (165K): [in this window] [in a new window] [Download PPT slide]   Figure 13b. MR imaging for breast cancer screening in patients at high risk. Images in a patient with a family history of breast cancer. (a) Mediolateral oblique mammographic view reveals dense breast tissue with no suggestive findings. (b) Sagittal computer-subtracted fat-suppressed contrast-enhanced 3D fast SPGR MR images (18.2/2.1) reveal two 7-mm enhancing lesions (arrows) in the superior lateral aspect of the left breast. Follow-up US (not shown) demonstrated two hypoechoic lesions in the upper outer quadrant that corresponded in size and location to the MR imaging-demonstrated lesions. US-guided fine-needle aspiration biopsy revealed adenocarcinoma from one lesion and atypia from the second lesion. The patient underwent bilateral mastectomies, and two invasive carcinomas (1.1-cm invasive ductal carcinoma and 3-mm invasive tubular carcinoma) were identified.

Family history has long been known to be an important risk factor for the development of breast cancer. Although noninherited factors play a role in familial clustering of breast cancer, recent discoveries in the field of molecular genetics have provided evidence of cancer-susceptibility genes that predispose to breast cancer, ovarian cancer, and other cancers. Inheritance is thought to be due to mutation in a single, highly penetrant, autosomal-dominant breast cancer susceptibility gene such as BRCA 1 or BRCA 2. Cancer susceptibility genes (including BRCA 1 and BRCA 2) are implicated in approximately 5%–10% of breast cancers (110).

Women with a known or suspected genetic mutation that places them at increased risk for the development of breast cancer are currently offered the options of prophylactic surgery, chemoprevention, or increased surveillance. The benefits of prophylactic mastectomy in reducing breast cancer risk are not known but are likely to be substantial (111). Research is ongoing to determine the potential reduction in cancer risk associated with chemopreventive drugs such as the antiestrogen tamoxifen. Current surveillance methods include screening mammography and physical examination. In high-risk individuals, suggested surveillance for breast cancer has included monthly breast self examination, clinical breast examination, and mammography every 6–12 months beginning between 25 and 35 years of age (110). However, it is not known whether increased surveillance will help reduce breast cancer mortality in women at high risk. There are concerns that mammography may have limited sensitivity in the detection of breast cancer in women younger than 40 years, who may be more likely to have dense tissue. These concerns have spurred investigation of adjunctive imaging tests such as MR imaging.

There are now several ongoing MR screening trials for women at high risk, including a pilot study funded by the National Cancer Institute and international clinical trials in Canada, England, Germany, France, Italy, and the Netherlands. While entrance criteria vary among these trials, in general patients are enrolled from cancer risk evaluation centers. Entrance criteria include patients who (a) are known carriers of a BRCA 1 or BRCA 2 mutation; (b) have a family member known to carry a BRCA 1 or BRCA 2 mutation but where the individual status is not known; (c) have a personal or family history highly suggestive of BRCA 1 or BRCA 2 involvement (guidelines vary); or (d) have at least a 25%–30% estimated lifetime risk for developing breast cancer, as based on the mode of Claus et al (112) or Gail et al (113). There is one recent report (114) in which it was shown that MR imaging can help detect mammographically and clinically occult breast cancer in high-risk populations. In that prospective study (114), nine cancers were detected on MR images in 192 asymptomatic women. Three of the nine cancers were detected only on MR images.

There is a growing clinical demand for screening breast MR imaging that is based on the promising results of diagnostic MR imaging. Unfortunately, screening MR imaging is being performed outside of clinical trials, in the absence of data demonstrating the efficacy of MR imaging as a screening modality. There are many requirements for a screening test, including adequate sensitivity and specificity, reproducibility of results, and affordability. At present, MR imaging does not meet these requirements. As discussed earlier, one of the major limitations of MR imaging of the breast remains its relatively low specificity. Many benign breast lesions, as well as presumably normal breast tissue, will demonstrate enhancement after intravenous administration of contrast material and may be indistinguishable from cancer, which could potentially result in a high number of biopsies of benign lesions or tissue. Thus, at present, we cannot recommend the use of MR imaging for breast cancer screening outside of clinical trials. Before MR imaging can be recommended as a method for breast cancer screening, additional clinical investigation is needed. In terms of screening for high-risk populations, MR imaging should be performed as part of a clinical trial. Patients being considered for MR imaging should undergo cancer risk evaluation prior to enrollment in a clinical MR imaging screening trial.

	CONCLUSION

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 
Results from clinical investigations have thus far demonstrated that MR imaging can offer clinically important information that cannot be obtained with conventional imaging methods; in the future, MR imaging will be an invaluable adjunctive breast imaging tool, just as breast US is today. However, MR imaging as a method to help detect, diagnose, and stage breast cancer remains in the developmental stage. The specificity of MR imaging appears to be limited by the overlap in enhancement kinetics and morphologic appearance of benign and malignant lesions. Yet in selected cases, the identification of certain morphologic features such as internal septa or the absence of enhancement may be used to classify a lesion as benign, offering an alternative to percutaneous or excisional biopsy. In contrast to its limited specificity, MR imaging is highly sensitive for the detection of both invasive carcinoma and DCIS. Perhaps most important, MR imaging can enable the detection of invasive and noninvasive breast carcinomas that are both mammographically and clinically occult, offering the potential for more accurate breast cancer staging and optimized treatment planning.

MR imaging is emerging as the most promising adjunctive imaging modality for breast cancer detection to date. However, published results are from studies with relatively small numbers of patients that were conducted almost exclusively in a diagnostic setting. The results of these studies should be validated in large-scale clinical trials before MR imaging is implemented clinically, outside of research settings, especially for breast cancer screening. This type of clinical investigation is needed to define the technical requirements for optimal imaging; to define criteria for image interpretation, including the development of an MR imaging lexicon; to develop accurate MR-guided localization and biopsy systems; to define the clinical indications for which MR imaging should be used as an adjunct to conventional imaging; and to address the issue of cost-effectiveness. Clinical trials to evaluate MR imaging of the breast as a diagnostic and screening tool are presently underway in the United States and abroad.

	FOOTNOTES

 
Abbreviations: DCIS = ductal carcinoma in situ, SPGR = spoiled gradient echo, 3D = three-dimensional

	REFERENCES

TOP ABSTRACT INTRODUCTION BREAST MR IMAGING TECHNIQUE... BREAST MR PROTOCOL OF... MR IMAGING-GUIDED BIOPSY IMAGE INTERPRETATION: WHAT... POTENTIAL CLINICAL APPLICATIONS LESION DETECTION BREAST CANCER DETECTION,... PROBLEM SOLVING: IS CANCER... BREAST CANCER STAGING PITFALLS OF MR IMAGING... QUESTIONS SURROUNDING MR IMAGING... BREAST CANCER STAGING WITH... MR IMAGING-GUIDED TREATMENT OF... BREAST CANCER SCREENING CONCLUSION REFERENCES

 

1. Heywang-Kobrunner SH. Contrast-enhanced magnetic resonance imaging of the breast. Invest Radiol 1994; 29:94-104.[CrossRef][Medline]
2. Kaiser WA, Zeitler E. MR imaging of the breast: fast imaging sequences with and without Gd-DTPA—preliminary observations. Radiology 1989; 170:681-686.[Abstract/Free Full Text]
3. Harms SE, Flamig DP, Hensley KL, et al. MR imaging of the breast with rotating delivery of excitation off resonance: clinical experience with pathologic correlation. Radiology 1993; 187:493-501.[Abstract/Free Full Text]
4. Orel SG, Schnall MD, LiVolsi VA, Troupin RH. Suspicious breast lesions: MR imaging with radiologic-pathologic correlation. Radiology 1994; 190:485-493.[Abstract/Free Full Text]
5. Boetes C, Barentsz JO, Mus RD, et al. MR characterization of suspicious breast lesions with a gadolinium-enhanced turboFLASH subtraction technique. Radiology 1994; 193:777-781.[Abstract/Free Full Text]
6. Gribbestad IS, Nilsen G, Fjosne H, et al. Contrast-enhanced magnetic resonance imaging of the breast. Acta Oncol 1992; 31:833-842.[Medline]
7. Gilles R, Guinebretiere JM, Lucidarme O, et al. Nonpalpable breast tumors: diagnosis with contrast-enhanced subtraction dynamic MR imaging. Radiology 1994; 191:625-631.[Abstract/Free Full Text]
8. Heywang SH, Wolf A, Pruss E, et al. MR imaging of the breast with Gd-DTPA: use and limitations. Radiology 1989; 171:95-103.[Abstract/Free Full Text]
9. Merchant TE, Thelissen GR, Kievit HC, et al. Breast disease evaluation with fat-suppressed magnetic resonance imaging. Magn Reson Imaging 1992; 10:335-340.[CrossRef][Medline]
10. Rubens D, Totterman S, Chacko A, et al. Gadopenetate dimeglumine-enhanced chemical-shift MR imaging of the breast. AJR Am J Roentgenol 1991; 157:267-270.[Abstract/Free Full Text]
11. Hylton NM, Frankel SD. Imaging techniques for breast MR imaging. Magn Reson Imaging Clin N Am 1994; 2:511-525.[Medline]
12. Daniel BL, Butts K, Glover GH, Cooper C, Herfkens FJ. Breast cancer: gadolinium-enhanced MR imaging with a 0.5-T open imager and three-point Dixon technique. Radiology 1998; 207:183-190.[Abstract/Free Full Text]
13. Insko EK, Connick TJ, Schnall MD, Orel SG. Multicoil array for high resolution imaging of the breast. Magn Reson Med 1997; 37:778-784.[Medline]
14. Sun L, Olsen JO, Robitaille PM. Design and optimization of a breast coil for magnetic resonance imaging. Magn Reson Imaging 1993; 11:73-80.[CrossRef][Medline]
15. Hylton NM, Kinkel K. Technical aspects of breast magnetic resonance imaging. Top Magn Reson Imaging 1998; 9:3-16.[Medline]
16. Heywang-Kobrunner SH, Haustein J, Beck R, et al. Contrast-enhanced MR imaging of the breast: comparison of two different doses of gadopentetate dimeglumine. Radiology 1994; 191:639-646.[Abstract/Free Full Text]
17. Hylton NM, Shimakawa A, Foo TKF, et al. A comparison of fast scan techniques for breast imaging (abstr). Berkeley, Calif: Society of Magnetic Resonance in Medicine, 1993; 2:856.
18. Hochman MG, Orel SG, Powell CM, Schnall MD, Reynolds CA. Fibroadenomas: MR imaging appearances with radiologic-histologic correlation. Radiology 1997; 204:123-129.[Abstract/Free Full Text]
19. Hulka CA, Smith BL, Sgroi DC, et al. Benign and malignant breast lesions: differentiation with echo-planar MR imaging. Radiology 1995; 197:33-38.[Abstract/Free Full Text]
20. Hulka CA, Edmister WB, Smith BL, et al. Dynamic echo-planar imaging of the breast: experience in diagnosing breast carcinoma and correlation with tumor angiogenesis. Radiology 1997; 205:837-842.[Abstract/Free Full Text]
21. Yen YF, Ikeda DM, Herflens RF, et al. Pharmacokinetic analysis of breast disease with dynamic spiral MRI (abstr). Proceedings of the Fourth Meeting of the International Society for Magnetic Resonance in Medicine Berkeley, Calif: International Society for Magnetic Resonance in Medicine, 1996; 745.
22. Chenevert TL, Helvie MA, Aisen AM, et al. Dynamic three-dimensional imaging with partial k-space sampling: initial application for gadolinium-enhanced rate characterization of breast lesions. Radiology 1995; 196:135-142.[Abstract/Free Full Text]
23. Greenman RL, Lenkinski RE, Schnall MD. Bilateral imaging using separate interleaved 3D volumes and dynamically switched multiple receive coil arrays. Magn Reson Med 1998; 39:108-115.[Medline]
24. Foo TKF, Sawyer AM, Faulkner WH, et al. Inversion in the steady state: contrast optimization and reduced imaging time with fast three-dimensional inversion-recovery-prepared GRE pulse sequences. Radiology 1994; 191:85-90.[Abstract/Free Full Text]
25. Federal Multi-Agency Consortium on Imaging Technologies to Improve Women’s Health. May 1, 1997 Washington, DC: , .
26. Fischer U, Vosshenrich R, Doler W, et al. MR imaging–guided breast intervention: experience with two systems. Radiology 1995; 195:533-538.[Abstract/Free Full Text]
27. Fischer U, Vosshenrich R, Keating D, et al. MR-guided biopsy of suspect breast lesions with a simple stereotaxic add-on device for surface coils. Radiology 1994; 192:272-273.[Abstract/Free Full Text]
28. Heywang-Koebrunner SH, II, Requardt H, Oellinger HJ, II, Fischer U, Viehweg P, Spielmann RP. Optimal procedure and coil design for MR imaging–guided transcutaneous needle localization and biopsy (abstr). Radiology 1994; 193(P):268.
29. Hussman K, Renslo R, Phillips JJ, et al. MR mammographic localizations: work in progress. Radiology 1993; 189:915-917.[Abstract/Free Full Text]
30. Kuhl CK, Elevelt A, Leutner CC, et al. Interventional breast MR imaging: clinical use of stereotactic localization and biopsy device. Radiology 1997; 204:667-675.[Abstract/Free Full Text]
31. Orel SG, Schnall MD, Newman RW, et al. MR imaging–guided localization and biopsy of breast lesions: initial experience. Radiology 1994; 193:97-102.[Abstract/Free Full Text]
32. Heywang-Koebrunner SH, Huynh AT, Viehweg P, et al. Prototype breast coil for MR guided needle localization. J Comput Assist Tomogr 1994; 18:876-881.[Medline]
33. Daniel BL, Birdwell RL, Ikeda DM, et al. Breast lesion localization: a free-hand interactive MR imaging technique. Radiology 1998; 207:455-463.[Abstract/Free Full Text]
34. Orel SG, Hochman MG, Schnall MD, Reynolds C, Sullivan DC. High-resolution MR imaging of the breast: clinical context. RadioGraphics 1996; 16:1385-1401.[Abstract]
35. Heywang-Koebrunner SH, Schaumloeffel-Schulze U, Heinig A, Beck RM, Lampe D, Buchmann J. MR-guided percutaneous vacuum biopsy of breast lesions: experiences with 100 lesions (abstr). Radiology 1999; 213(P):289.[Abstract/Free Full Text]
36. Stack JP, Redmond OM, Codd MB, Dervan PA, Ennis JT. Breast disease: tissue characterization with Gd-DTPA enhancement profiles. Radiology 1990; 174:491-494.[Abstract/Free Full Text]
37. Flickinger FW, Allison JD, Sherry RM, et al. Differentiation of benign from malignant breast masses by time-intensity evaluation of contrast-enhanced MRI. Magn Reson Imaging 1993; 11:617-620.[CrossRef][Medline]
38. Hickman PF, Moore NR, Shepstone BJ. The indeterminate breast mass: assessment using contrast enhanced magnetic resonance imaging. Br J Radiol 1994; 67:14-20.[Abstract/Free Full Text]
39. Kuhl CK, Bieling HB, Gieseke J, et al. Healthy premenopausal breast parenchyma in dynamic contrast-enhanced MR imaging of the breast: normal contrast medium enhancement and cyclical-phase dependency. Radiology 1997; 203:137-144.[Abstract/Free Full Text]
40. Kuhl CK, Mielcareck P, Klaschik S, et al. Dynamic breast MR imaging: are signal intensity time course data useful for differential diagnosis of enhancing lesions?. Radiology 1999; 211:101-110.[Abstract/Free Full Text]
41. Stomper PC, Herman S, Klippenstein DL, et al. Suspect breast lesions: findings at dynamic gadolinium-enhanced MR imaging correlated with mammographic and pathologic features. Radiology 1995; 197:387-395.[Abstract/Free Full Text]
42. Kelcz F, Santyr G. Gadolinium-enhanced breast MRI. Crit Rev Diagn Imaging 1995; 36:287-338.[Medline]
43. Schimpfle MM, Ohmenhauser K, Sand J, Stoll P, Claussen CD. Dynamic 3D-MR mammography: is there a benefit of sophisticated evaluation of enhancement curves for clinical routine?. J Magn Reson Imaging 1997; 7:236-240.[Medline]
44. Mussurakis S, Buckley DL, Horsman A. Dynamic MRI of invasive breast cancer: assessment of three region-of-interest analysis methods. J Comp Assist Tomogr 1997; 21:431-438.[CrossRef][Medline]
45. Brinck U, Fischer U, Korabiowska M, Jutrowski M, Schauer A, Grabbe E. The variability of fibroadenoma in contrast-enhanced dynamic MR mammography. AJR Am J Roentgenol 1997; 168:1331-1334.[Free Full Text]
46. Orel SG. Differentiating benign from malignant enhancing lesions identified at MR imaging of the breast: are time–signal intensity curves an accurate predictor? (editorial). Radiology 1999; 211:5-7.[Free Full Text]
47. Orel SG, Mendonca MH, Reynolds C, et al. MR imaging of ductal carcinoma in situ. Radiology 1997; 202:413-420.[Abstract/Free Full Text]
48. Buadu LD, Murakami J, Murayama S, et al. Patterns of peripheral enhancement in breast masses: correlation of findings on contrast medium enhanced MRI with histologic features and tumor angiogenesis. J Comp Assist Tomogr 1997; 21:421-430.[CrossRef][Medline]
49. Buadu LD, Murakami J, Murayama S, et al. Breast lesions: correlation of contrast medium enhancement patterns on MR images with histopathologic findings and tumor angiogenesis. Radiology 1996; 200:639-649.[Abstract/Free Full Text]
50. Sherif H, Mahfouz AE, Oellinger H, et al. Peripheral washout sign on contrast-enhanced MR images of the breast. Radiology 1997; 205:209-213.[Abstract/Free Full Text]
51. Soderstrom CE, Harms SE, Copit DS, et al. Three-dimensional RODEO breast MR imaging of lesions containing ductal carcinoma in situ. Radiology 1996; 201:427-432.[Abstract/Free Full Text]
52. Gilles R, Zafrani B, Guinebretiere JM, et al. Ductal carcinoma in situ: MR imaging—histopathologic correlation. Radiology 1995; 196:415-419.[Abstract/Free Full Text]
53. Stelling CB, Powell DE, Mattingly SS. Fibroadenomas: histopathologic and MR imaging features. Radiology 1987; 162:399-407.[Abstract/Free Full Text]
54. Nunes LW, Schnall MD, Orel SG, et al. Breast MR imaging: interpretation model. Radiology 1997; 202:833-841.[Abstract/Free Full Text]
55. Harms SE. Technical report of the International Working Group on Breast MRI. J Magn Reson Imaging 1999; 10:979.[CrossRef][Medline]
56. Liu PF, Debatin JF, Caduff RF, et al. Improved diagnostic accuracy in dynamic contrast enhanced MRI of the breast by combined quantitative and qualitative analysis. Br J Radiol 1998; 71:501-509.[Abstract]
57. Kopans DB. Preoperative imaging-guided needle placement and localization of clinically occult lesions. In: Kopans DB, eds. Breast imaging. Philadelphia, Pa: Lippincott, 1989; 320-341.
58. Kaiser WA, Reiser M. False-positive cases in dynamic MR mammography (abstr). Radiology 1992; 185(P):245.
59. Fobben ES, Rubin CZ, Kalisher L, et al. Breast MR imaging with commercially available techniques: radiologic-pathologic correlation. Radiology 1995; 196:143-152.[Abstract/Free Full Text]
60. Nunes LW, Schnall MD, Siegelman ES, et al. Diagnostic performance characteristics of architectural features revealed by high spatial-resolution MR imaging of the breast. AJR Am J Roentgenol 1997; 169:409-415.[Abstract/Free Full Text]
61. Muller-Schimpfle M, Ohmenhauser K, Stoll P, Dietz K, Claussen CD. Menstrual cycle and age: influence of parenchymal contrast medium enhancement in MR imaging of the breast. Radiology 1997; 203:145-149.[Abstract/Free Full Text]
62. Jackman RJ, Nowels KW, Shepard MJ, Finkelstein SI, Marsoni FA, Jr. Stereotaxic large-core needle biopsy of 450 nonpalpable breast lesions with surgical correlation in lesions with cancer or atypical hyperplasia. Radiology 1994; 193:91-95.[Abstract/Free Full Text]
63. Jackson VP. The status of mammographically guided fine needle aspiration biopsy of non-palpable breast lesions. Radiol Clin North Am 1992; 30:155-166.[Medline]
64. Lee CH, Egglin TK, Philpotts K, Mainiero MB, Tocino I. Cost-effectiveness of stereotactic core needle biopsy: analysis by means of mammographic findings. Radiology 1997; 202:849-854.[Abstract/Free Full Text]
65. Parker SH, Jobe WE, Dennis MA, et al. US-guided automated large-core breast biopsy. Radiology 1993; 187:507-511.[Abstract/Free Full Text]
66. Parker SH, Lovin JD, Jobe WE, et al. Nonpalpable breast lesions: stereotactic automated large-core biopsies. Radiology 1991; 180:403-407.[Abstract/Free Full Text]
67. Lieberman L, Fahs MC, Dershaw DD, et al. Impact of stereotaxic core biopsy on cost of diagnosis. Radiology 1995; 195:633-637.[Abstract/Free Full Text]
68. Homer MJ. Mammographic interpretation: a practical approach New York, NY: McGraw-Hill, 1991; 4-5.
69. Rodenko GN, Harms SE, Pruneda JM, et al. MR imaging in the management before surgery of lobular carcinoma of the breast: correlation with pathology. AJR Am J Roentgenol 1996; 167:1415-1419.[Abstract/Free Full Text]
70. Boetes C, Mus RD, Holland R, et al. Breast tumors: comparative accuracy of MR imaging relative to mammography and US for demonstrating extent. Radiology 1995; 197:43-47.
71. Weinstein SP, Orel SG, Heller R, et al. MR imaging of the breast in patients with invasive lobular carcinoma. AJR Am J Roentgenol 2001; 176:399-406.[Abstract/Free Full Text]
72. Piccoli CW, Matteucci T, Outwater EK, Siegelman ES, Mitchell DG. Breast cancer diagnosis with MR imaging: effect of clinical and mammographic findings on recommendations for biopsy. Radiology 1995; 196:415-419.
73. Westerhof JP, Fischer U, Moritz JD, Oestmann JW. MR imaging of mammographically detected clustered microcalcifications: is there any value?. Radiology 1998; 207:675-681.[Abstract/Free Full Text]
74. Folkman J. What is the evidence that tumors are angiogensis dependent?. J Natl Cancer Inst 1990; 82:4-6.[Free Full Text]
75. Weidner N, Semple JP, Welch WR, Folkman J. Tumor angiogenesis and metastasis: correlation in invasive breast carcinoma. N Engl J Med 1991; 324:1-8.[Abstract]
76. Guidi AJ, Fischer L, Harris JR, Schnitt SJ. Microvessel density and distribution in ductal carcinoma in situ of the breast. J Natl Cancer Inst 1994; 86:614-619.[Abstract/Free Full Text]
77. Lee CH, Smith RC, Levine JA, Troiano RN, Tocino I. Clinical usefulness of MR imaging of the breast in the evaluation of the problematic mammogram. AJR Am J Roentgenol 1999; 173:1323-1329.[Abstract/Free Full Text]
78. Orel SG. High-resolution MR imaging for the detection, diagnosis, and staging of breast cancer. RadioGraphics 1998; 18:903-912.[Medline]
79. Buckley DL, Mussurakis S, Horsman A. Effect of temporal resolution on the diagnostic efficacy of contrast-enhanced MRI in the conservatively treated breast. J Comput Assist Tomogr 1998; 22:47-51.[CrossRef][Medline]
80. Drew PJ, Kerin MJ, Turnbull LW, et al. Routine screening for local recurrence following breast-conserving therapy for cancer with dynamic contrast-enhanced magnetic resonance imaging of the breast. Ann Surg Oncol 1998; 3:265-270.
81. Dao TH, Rahmouni A, Campana F, et al. Tumor recurrence versus fibrosis in the irradiated breast: differentiation with dynamic gadolinium-enhanced MR imaging. Radiology 1993; 187:752-755.
82. Gilles R, Guinebretiere JM, Shapeero LG, et al. Assessment of breast cancer recurrence with contrast-enhanced subtraction MR imaging: preliminary results in 26 patients. Radiology 1993; 188:473-478.[Abstract/Free Full Text]
83. Heywang-Koebrunner SH, Schlegel A, Beck R, et al. Contrast-enhanced MRI of the breast after limited surgery and radiation therapy. J Comput Assist Tomogr 1993; 17:891-900.[Medline]
84. Lewis-Jones HG, Whitehouse GH, Leinster SJ. The role of magnetic resonance imaging in the assessment of local recurrent breast carcinoma. Clin Radiol 1991; 43:197-204.[CrossRef][Medline]
85. Mumtaz H, Davidson T, Hall-Craggs MA, et al. Comparison of magnetic resonance imaging and conventional triple assessment in locally recurrent breast cancer. Br J Surg 1997; 84:1147-1151.[CrossRef][Medline]
86. Muuller RD, Barkhausen J, Sauerwein W, Langer R. Assessment of local recurrence after breast-conserving therapy with MRI. J Comput Assist Tomogr 1998; 22:408-412.[CrossRef][Medline]
87. Rieber A, Merkle E, Zeitler H, et al. Value of MR mammography in the detection and exclusion of recurrent breast carcinoma. J Compt Assist Tomogr 1997; 21:780-784.[CrossRef][Medline]
88. Solomon B, Orel SG, Reynolds C, Schnall MD. Delayed development of enhancement in fat necrosis after breast conservation therapy: a potential pitfall of MR imaging of the breast. AJR Am J Roentgenol 1998; 170:966-968.[Free Full Text]
89. Whitehouse GH, Moore NR. MR imaging of the breast after surgery for breast cancer. Magn Reson Imaging Clin N Am 1994; 2:591-603.[Medline]
90. Orel SG, Schnall MD, Powell CM, et al. Staging of suspected breast cancer: effect of MR imaging and MR-guided biopsy. Radiology 1995; 196:115-122.[Abstract/Free Full Text]
91. Cooney BS, Orel SG, Schnall MD, Troupin RH. Invasive lobular carcinoma in a patient with synchronous ductal carcinoma in situ: detection with MR imaging. AJR Am J Roentgenol 1994; 162:1318-1320.[Free Full Text]
92. Essermann L, Hylton N, Yassa L, et al. Utility of magnetic resonance imaging in the management of breast cancer: evidence for improved preoperative staging. J Clin Oncol 1999; 17:110-119.[Abstract/Free Full Text]
93. Fischer U, Kopka L, Grabbe E. Breast carcinoma: effect of preoperative contrast-enhanced MR imaging on the therapeutic approach. Radiology 1999; 213:881-888.[Abstract/Free Full Text]
94. Mumtaz H, Hall-Craggs MA, Davidson T, et al. Staging of symptomatic primary breast cancer with MR imaging. AJR Am J Roentgenol 1997; 169:417-424.[Abstract/Free Full Text]
95. Orel SG, Reynolds C, Schnall MD. Breast carcinoma: MR imaging before re-excisional biopsy. Radiology 1997; 205:429-436.[Abstract/Free Full Text]
96. Soderstrom CE, Harms SE, Farrell RS, Pruneda JM, Flamig DP. Detection with MR imaging of residual tumor in the breast soon after surgery. AJR Am J Roentgenol 1997; 168:485-488.[Abstract/Free Full Text]
97. Solin LJ. Special considerations. In: Fowble B, Goodman RL, Glick JH, Rosato EF, eds. Breast cancer treatment: a comprehensive guide to management. St Louis, Mo: Mosby–Year Book, 1991; 523-528.
98. Morris EA, Schwartz LH, Dershaw DD, et al. MR imaging of the breast in patients with occult primary breast carcinoma. Radiology 1997; 205:437-440.[Abstract/Free Full Text]
99. Orel SG, Weinstein SP, Schnall MD, et al. Breast MR imaging in patients with axillary node metastases and unknown primary malignancy. Radiology 1999; 212:543-549.[Abstract/Free Full Text]
100. Schorn C, Fischer U, Luftner N, Westerhof JP, Grabbe E. MRI of the breast in patients with metastatic disease of unknown primary. Eur Radiol 1999; 9:470-473.[CrossRef][Medline]
101. Tilanus-Linthorst MM, Obdeijn AI, Bontenbal M, Oudkerk M. MRI in patients with axillary metastases of occult breast carcinoma. Breast Cancer Res Treat 1997; 44:179-182.[Medline]
102. Hortobagyi GN, Ames FC, Buzdar AU, et al. Management of stage III primary breast cancer with primary chemotherapy, surgery, and radiation therapy. Cancer 1983; 51:2507-2516.
103. Lopez MJ, Andriole DP, Kraybill WG, Khojasteh A. Multimodal therapy in locally advanced breast carcinoma. Am J Surg 1990; 160:669-674.[CrossRef][Medline]
104. Gilles R, Guinebretiere JM, Toussaint C, et al. Locally advanced breast cancer: contrast-enhanced subtraction MR imaging of response to preoperative chemotherapy. Radiology 1994; 191:633-638.[Abstract/Free Full Text]
105. Rieber A, Zeitler H, Rosenthal H, et al. MRI of breast cancer: influence of chemotherapy on sensitivity. Br J Radiol 1997; 70:452-458.[Abstract]
106. Mumtaz H, Hall-Craggs MA, Wotherspoon A, et al. Laser therapy for breast cancer: MR imaging and histopathologic correlation. Radiology 1996; 200:651-658.[Abstract/Free Full Text]
107. Harms SE. Integration of breast magnetic resonance imaging with breast cancer treatment. Top Magn Reson Imaging 1998; 9:79-91.[Medline]
108. Bennion RS, Love SM. Treatment of breast disease. In: Bassett LW, Jackson VP, Jahan R, Fu YS, Gold RH, eds. Diagnosis of diseases of the breast. Philadelphia, Pa: Saunders, 1997; 521-545.
109. Slanetz PJ, Edmister WB, Weisskoff RM, et al. Occult contralateral breast cancer detected by breast MR (abstr). Radiology 1998; 209(P):467.
110. Hoskins KF, Stopfer JE, Calzone KA, et al. Assessment and counseling for women with a family history of breast cancer. JAMA 1995; 273:577-585.[Abstract/Free Full Text]
111. Hartmann LC, Schaid DJ, Woods JE, et al. Efficacy of bilateral prophylactic mastectomy in women with a family history of breast cancer. N Engl J Med 1999; 340:77-84.[Abstract/Free Full Text]
112. Claus EB, Risch N, Thompson WD. Autosomal dominant inheritance of early onset breast cancer. Cancer 1994; 73:643-651.[CrossRef][Medline]
113. Gail MH, Brinton LA, Byar DP, et al. Projecting individualized probabilities of developing breast cancer for white females who are being examined annually. J Natl Cancer Inst 1989; 81:1879-1886.[Abstract/Free Full Text]
114. Kuhl CK, Schmutzer RK, Leutner CC, et al. Breast MR imaging screening in 192 women proved or suspected to be carriers of a breast cancer susceptibility gene: preliminary results. Radiology 2000; 215:267-279.[Abstract/Free Full Text]

This article has been cited by other articles:

				G. Manenti, F. Bolacchi, T. Perretta, E. Cossu, C. A. Pistolese, O. C. Buonomo, E. Bonanno, A. Orlandi, and G. Simonetti Small Breast Cancers: In Vivo Percutaneous US-guided Radiofrequency Ablation with Dedicated Cool-Tip Radiofrequency System Radiology, May 1, 2009; 251(2): 339 - 346. [Abstract] [Full Text] [PDF]

				W. B. DeMartini, P. R. Eby, S. Peacock, and C. D. Lehman Utility of Targeted Sonography for Breast Lesions That Were Suspicious on MRI Am. J. Roentgenol., April 1, 2009; 192(4): 1128 - 1134. [Abstract] [Full Text] [PDF]

				H. Elsamaloty, M. S. Elzawawi, S. Mohammad, and N. Herial Increasing Accuracy of Detection of Breast Cancer with 3-T MRI Am. J. Roentgenol., April 1, 2009; 192(4): 1142 - 1148. [Abstract] [Full Text] [PDF]

				S. Monzawa, M. Yokokawa, T. Sakuma, S. Takao, K. Hirokaga, K. Hanioka, and S. Adachi Mucinous Carcinoma of the Breast: MRI Features of Pure and Mixed Forms with Histopathologic Correlation Am. J. Roentgenol., March 1, 2009; 192(3): W125 - W131. [Abstract] [Full Text] [PDF]

				S. Raza, M. Vallejo, S. A. Chikarmane, and R. L. Birdwell Pure Ductal Carcinoma in Situ: A Range of MRI Features Am. J. Roentgenol., September 1, 2008; 191(3): 689 - 699. [Abstract] [Full Text] [PDF]

				J. A. Harvey, B. T. Nicholson, and M. A. Cohen Finding Early Invasive Breast Cancers: A Practical Approach Radiology, July 1, 2008; 248(1): 61 - 76. [Abstract] [Full Text] [PDF]

				J. Godinez, E. C. Gombos, S. A. Chikarmane, G. K. Griffin, and R. L. Birdwell Breast MRI in the Evaluation of Eligibility for Accelerated Partial Breast Irradiation Am. J. Roentgenol., July 1, 2008; 191(1): 272 - 277. [Abstract] [Full Text] [PDF]

				A. Perrone, L. Lo Mele, S. Sassi, M. Marini, L. Testaverde, L. Izzo, and M. Marini MDCT of the Breast Am. J. Roentgenol., June 1, 2008; 190(6): 1644 - 1651. [Abstract] [Full Text] [PDF]

				A. Gossmann, C. Bangard, M. Warm, R. K. Schmutzler, P. Mallmann, and K.-J. Lackner Real-time MR-guided Wire Localization of Breast Lesions by Using an Open 1.0-T Imager: Initial Experience Radiology, May 1, 2008; 247(2): 535 - 542. [Abstract] [Full Text] [PDF]

				L. J. Solin, S. G. Orel, W.-T. Hwang, E. E. Harris, and M. D. Schnall Relationship of Breast Magnetic Resonance Imaging to Outcome After Breast-Conservation Treatment With Radiation for Women With Early-Stage Invasive Breast Carcinoma or Ductal Carcinoma in Situ J. Clin. Oncol., January 20, 2008; 26(3): 386 - 391. [Abstract] [Full Text] [PDF]

				S. H. Javid, J. W. Carlson, J. E. Garber, R. L. Birdwell, S. Lester, S. Lipsitz, and M. Golshan Breast MRI Wire-Guided Excisional Biopsy: Specimen Size as Compared to Mammogram Wire-Guided Excisional Biopsy and Implications for Use. Ann. Surg. Oncol., December 1, 2007; 14(12): 3352 - 3358. [Abstract] [Full Text] [PDF]

				C. C. Riedl, L. Ponhold, D. Flory, M. Weber, R. Kroiss, T. Wagner, M. Fuchsjager, and T. H. Helbich Magnetic Resonance Imaging of the Breast Improves Detection of Invasive Cancer, Preinvasive Cancer, and Premalignant Lesions during Surveillance of Women at High Risk for Breast Cancer Clin. Cancer Res., October 15, 2007; 13(20): 6144 - 6152. [Abstract] [Full Text] [PDF]

				M. E. Noz and G. Q. Maguire Jr. Reply: 18F-FDG PET in Detecting Primary Breast Cancer J. Nucl. Med., October 1, 2007; 48(10): 1752 - 1752. [Full Text] [PDF]

				J. A. Harvey, R. E. Hendrick, J. M. Coll, B. T. Nicholson, B. T. Burkholder, and M. A. Cohen Breast MR Imaging Artifacts: How to Recognize and Fix Them RadioGraphics, October 1, 2007; 27(suppl_1): S131 - S145. [Abstract] [Full Text] [PDF]

				L. Bartella and W. Huang Proton (1H) MR Spectroscopy of the Breast RadioGraphics, October 1, 2007; 27(suppl_1): S241 - S252. [Abstract] [Full Text] [PDF]

				C. Kuhl The Current Status of Breast MR Imaging * Part I. Choice of Technique, Image Interpretation, Diagnostic Accuracy, and Transfer to Clinical Practice Radiology, August 1, 2007; 244(2): 356 - 378. [Abstract] [Full Text] [PDF]

				P Veit-Haibach, G Antoch, T Beyer, H Stergar, R Schleucher, E A M Hauth, and A Bockisch FDG-PET/CT in restaging of patients with recurrent breast cancer: possible impact on staging and therapy Br. J. Radiol., July 1, 2007; 80(955): 508 - 515. [Abstract] [Full Text] [PDF]

				P. Fu, Y. Kurihara, Y. Kanemaki, K. Okamoto, Y. Nakajima, M. Fukuda, and I. Maeda High-Resolution MRI in Detecting Subareolar Breast Abscess Am. J. Roentgenol., June 1, 2007; 188(6): 1568 - 1572. [Abstract] [Full Text] [PDF]

				F. Pediconi, C. Catalano, A. Roselli, S. Padula, F. Altomari, E. Moriconi, A. M. Pronio, M. A. Kirchin, and R. Passariello Contrast-enhanced MR Mammography for Evaluation of the Contralateral Breast in Patients with Diagnosed Unilateral Breast Cancer or High-Risk Lesions Radiology, June 1, 2007; 243(3): 670 - 680. [Abstract] [Full Text] [PDF]

				D. Saslow, C. Boetes, W. Burke, S. Harms, M. O. Leach, C. D. Lehman, E. Morris, E. Pisano, M. Schnall, S. Sener, et al. American Cancer Society Guidelines for Breast Screening with MRI as an Adjunct to Mammography CA Cancer J Clin, March 1, 2007; 57(2): 75 - 89. [Abstract] [Full Text] [PDF]

				L. Liberman, A. E. Holland, D. Marjan, M. P. Murray, L. Bartella, E. A. Morris, D. D. Dershaw, and R. T. Wynn Underestimation of Atypical Ductal Hyperplasia at MRI-Guided 9-Gauge Vacuum-Assisted Breast Biopsy Am. J. Roentgenol., March 1, 2007; 188(3): 684 - 690. [Abstract] [Full Text] [PDF]

				C. C. Genson, C. E. Blane, M. A. Helvie, S. A. Waits, and T. L. Chenevert Effects on Breast MRI of Artifacts Caused by Metallic Tissue Marker Clips Am. J. Roentgenol., February 1, 2007; 188(2): 372 - 376. [Abstract] [Full Text] [PDF]

				M. Memarsadeghi, C. C. Riedl, A. Kaneider, A. Galid, M. Rudas, W. Matzek, and T. H. Helbich Axillary Lymph Node Metastases in Patients with Breast Carcinomas: Assessment with Nonenhanced versus USPIO-enhanced MR Imaging. Radiology, November 1, 2006; 241(2): 367 - 377. [Abstract] [Full Text] [PDF]

				C. Dromain, C. Balleyguier, S. Muller, M.-C. Mathieu, F. Rochard, P. Opolon, and R. Sigal Evaluation of tumor angiogenesis of breast carcinoma using contrast-enhanced digital mammography. Am. J. Roentgenol., November 1, 2006; 187(5): W528 - W537. [Abstract] [Full Text] [PDF]

				D. R. Rausch and R. E. Hendrick How to Optimize Clinical Breast MR Imaging Practices and Techniques on Your 1.5-T System RadioGraphics, September 1, 2006; 26(5): 1469 - 1484. [Abstract] [Full Text] [PDF]

				M. Tozaki, T. Igarashi, and K. Fukuda Breast MRI using the VIBE sequence: clustered ring enhancement in the differential diagnosis of lesions showing non-masslike enhancement. Am. J. Roentgenol., August 1, 2006; 187(2): 313 - 321. [Abstract] [Full Text] [PDF]

				M. Tozaki and K. Fukuda High-spatial-resolution MRI of non-masslike breast lesions: interpretation model based on BI-RADS MRI descriptors. Am. J. Roentgenol., August 1, 2006; 187(2): 330 - 337. [Abstract] [Full Text] [PDF]

				P. D. Friedman, S. V. Swaminathan, K. Herman, and L. Kalisher Breast MRI: the importance of bilateral imaging. Am. J. Roentgenol., August 1, 2006; 187(2): 345 - 349. [Full Text] [PDF]

				S. V. Ghate, E. L. Rosen, M. S. C. Soo, and J. A. Baker MRI-guided vacuum-assisted breast biopsy with a handheld portable biopsy system. Am. J. Roentgenol., June 1, 2006; 186(6): 1733 - 1736. [Abstract] [Full Text] [PDF]

				L. Bartella, E. A. Morris, D. D. Dershaw, L. Liberman, S. B. Thakur, C. Moskowitz, J. Guido, and W. Huang Proton MR Spectroscopy with Choline Peak as Malignancy Marker Improves Positive Predictive Value for Breast Cancer Diagnosis: Preliminary Study Radiology, June 1, 2006; 239(3): 686 - 692. [Abstract] [Full Text] [PDF]

				L. Bartella, L. Liberman, E. A. Morris, and D. D. Dershaw Nonpalpable mammographically occult invasive breast cancers detected by MRI. Am. J. Roentgenol., March 1, 2006; 186(3): 865 - 870. [Abstract] [Full Text] [PDF]

				S. G. Orel, M. Rosen, C. Mies, and M. D. Schnall MR Imaging-guided 9-gauge Vacuum-assisted Core-Needle Breast Biopsy: Initial Experience Radiology, December 1, 2005; 238(1): 54 - 61. [Abstract] [Full Text] [PDF]

				A. Malich, D. R. Fischer, S. Wurdinger, J. Boettcher, C. Marx, M. Facius, and W. A. Kaiser Potential MRI Interpretation Model: Differentiation of Benign from Malignant Breast Masses Am. J. Roentgenol., October 1, 2005; 185(4): 964 - 970. [Abstract] [Full Text] [PDF]

				F. Pediconi, C. Catalano, R. Occhiato, F. Venditti, F. Fraioli, A. Napoli, M. A. Kirchin, and R. Passariello Breast Lesion Detection and Characterization at Contrast-enhanced MR Mammography: Gadobenate Dimeglumine versus Gadopentetate Dimeglumine Radiology, October 1, 2005; 237(1): 45 - 56. [Abstract] [Full Text] [PDF]

				S. Ghai, D. Muradali, K. Bukhanov, and S. Kulkarni Nonenhancing Breast Malignancies on MRI: Sonographic and Pathologic Correlation Am. J. Roentgenol., August 1, 2005; 185(2): 481 - 487. [Abstract] [Full Text] [PDF]

				S. Meisamy, P. J. Bolan, E. H. Baker, M. G. Pollema, C. T. Le, F. Kelcz, M. C. Lechner, B. A. Luikens, R. A. Carlson, K. R. Brandt, et al. Adding in Vivo Quantitative 1H MR Spectroscopy to Improve Diagnostic Accuracy of Breast MR Imaging: Preliminary Results of Observer Performance Study at 4.0 T Radiology, August 1, 2005; 236(2): 465 - 475. [Abstract] [Full Text] [PDF]

				L. A. Newman and H. M. Kuerer Advances in Breast Conservation Therapy J. Clin. Oncol., March 10, 2005; 23(8): 1685 - 1697. [Full Text] [PDF]

				J. I. Wiener, K. J. Schilling, C. Adami, and N. A. Obuchowski Assessment of Suspected Breast Cancer by MRI: A Prospective Clinical Trial Using a Combined Kinetic and Morphologic Analysis Am. J. Roentgenol., March 1, 2005; 184(3): 878 - 886. [Abstract] [Full Text] [PDF]

				D. A. Bluemke, C. A. Gatsonis, M. H. Chen, G. A. DeAngelis, N. DeBruhl, S. Harms, S. H. Heywang-Kobrunner, N. Hylton, C. K. Kuhl, C. Lehman, et al. Magnetic Resonance Imaging of the Breast Prior to Biopsy JAMA, December 8, 2004; 292(22): 2735 - 2742. [Abstract] [Full Text] [PDF]

				J J Echevarria, J A Lopez-Ruiz, D Martin, I Imaz, and M Martin Usefulness of MRI in detecting occult breast cancer associated with Paget's disease of the nipple-areolar complex Br. J. Radiol., December 1, 2004; 77(924): 1036 - 1039. [Abstract] [Full Text] [PDF]

				F. Sardanelli, G. M. Giuseppetti, P. Panizza, M. Bazzocchi, A. Fausto, G. Simonetti, V. Lattanzio, and A. Del Maschio Sensitivity of MRI Versus Mammography for Detecting Foci of Multifocal, Multicentric Breast Cancer in Fatty and Dense Breasts Using the Whole-Breast Pathologic Examination as a Gold Standard Am. J. Roentgenol., October 1, 2004; 183(4): 1149 - 1157. [Abstract] [Full Text] [PDF]

				R. K. Devon, M. A. Rosen, C. Mies, and S. G. Orel Breast Reconstruction with a Transverse Rectus Abdominis Myocutaneous Flap: Spectrum of Normal and Abnormal MR Imaging Findings RadioGraphics, September 1, 2004; 24(5): 1287 - 1299. [Abstract] [Full Text] [PDF]

				M. Kriege, C. T.M. Brekelmans, C. Boetes, P. E. Besnard, H. M. Zonderland, I. M. Obdeijn, R. A. Manoliu, T. Kok, H. Peterse, M. M.A. Tilanus-Linthorst, et al. Efficacy of MRI and Mammography for Breast-Cancer Screening in Women with a Familial or Genetic Predisposition N. Engl. J. Med., July 29, 2004; 351(5): 427 - 437. [Abstract] [Full Text] [PDF]

				X. Chen, C. D. Lehman, and K. E. Dee MRI-Guided Breast Biopsy: Clinical Experience with 14-Gauge Stainless Steel Core Biopsy Needle Am. J. Roentgenol., April 1, 2004; 182(4): 1075 - 1080. [Abstract] [Full Text] [PDF]

				M.L. Quan, L. Sclafani, A.S. Heerdt, J.V. Fey, E.A. Morris, and P.I. Borgen Magnetic Resonance Imaging Detects Unsuspected Disease in Patients With Invasive Lobular Cancer Ann. Surg. Oncol., November 1, 2003; 10(9): 1048 - 1053. [Abstract] [Full Text] [PDF]

				R. Arriagada, M. G. Le, J.-M. Guinebretiere, A. Dunant, F. Rochard, and T. Tursz Late local recurrences in a randomised trial comparing conservative treatment with total mastectomy in early breast cancer patients Ann. Onc., November 1, 2003; 14(11): 1617 - 1622. [Abstract] [Full Text] [PDF]

				E. D. Yeh Characterization of Breast Lesions with Proton MR Spectroscopy Am. J. Roentgenol., November 1, 2003; 181(5): 1273 - 1274. [Full Text] [PDF]

				E. L. Rosen, K. L. Blackwell, J. A. Baker, M. S. Soo, R. C. Bentley, D. Yu, T. V. Samulski, and M. W. Dewhirst Accuracy of MRI in the Detection of Residual Breast Cancer After Neoadjuvant Chemotherapy Am. J. Roentgenol., November 1, 2003; 181(5): 1275 - 1282. [Abstract] [Full Text] [PDF]

				M. A. Jacobs, P. B. Barker, D. A. Bluemke, C. Maranto, C. Arnold, E. H. Herskovits, and Z. Bhujwalla Benign and Malignant Breast Lesions: Diagnosis with Multiparametric MR Imaging Radiology, October 1, 2003; 229(1): 225 - 232. [Abstract] [Full Text] [PDF]

				E. A. Morris, L. Liberman, D. J. Ballon, M. Robson, A. F. Abramson, A. Heerdt, and D. D. Dershaw MRI of Occult Breast Carcinoma in a High-Risk Population Am. J. Roentgenol., September 1, 2003; 181(3): 619 - 626. [Abstract] [Full Text] [PDF]

				M. V. Knopp, M. W. Bourne, F. Sardanelli, M. N. Wasser, L. Bonomo, C. Boetes, M. Muller-Schimpfle, M. A. Hall-Craggs, B. Hamm, A. Orlacchio, et al. Gadobenate Dimeglumine-Enhanced MRI of the Breast: Analysis of Dose Response and Comparison with Gadopentetate Dimeglumine Am. J. Roentgenol., September 1, 2003; 181(3): 663 - 676. [Abstract] [Full Text] [PDF]

				M. Inoue, T. Sano, R. Watai, R. Ashikaga, K. Ueda, M. Watatani, and Y. Nishimura Dynamic Multidetector CT of Breast Tumors: Diagnostic Features and Comparison with Conventional Techniques Am. J. Roentgenol., September 1, 2003; 181(3): 679 - 686. [Abstract] [Full Text] [PDF]

				L. Liberman, E. A. Morris, D. D. Dershaw, A. F. Abramson, and L. K. Tan Ductal Enhancement on MR Imaging of the Breast Am. J. Roentgenol., August 1, 2003; 181(2): 519 - 525. [Abstract] [Full Text] [PDF]

				L. R. LaTrenta, J. H. Menell, E. A. Morris, A. F. Abramson, D. D. Dershaw, and L. Liberman Breast Lesions Detected with MR Imaging: Utility and Histopathologic Importance of Identification with US Radiology, June 1, 2003; 227(3): 856 - 861. [Abstract] [Full Text] [PDF]

				L. Liberman, E. A. Morris, D. D. Dershaw, A. F. Abramson, and L. K. Tan MR Imaging of the Ipsilateral Breast in Women with Percutaneously Proven Breast Cancer Am. J. Roentgenol., April 1, 2003; 180(4): 901 - 910. [Abstract] [Full Text] [PDF]

				L. Liberman, E. A. Morris, C. M. Kim, J. B. Kaplan, A. F. Abramson, J. H. Menell, K. J. Van Zee, and D. D. Dershaw MR Imaging Findings in the Contralateral Breast of Women with Recently Diagnosed Breast Cancer Am. J. Roentgenol., February 1, 2003; 180(2): 333 - 341. [Abstract] [Full Text] [PDF]

				R. J. Brenner, E. A. Morris, L. Liberman, and D. D. Dershaw Needle Localization of Breast Lesions: Localizing Data Am. J. Roentgenol., December 1, 2002; 179 (6): 1643 - 1644. [Full Text] [PDF]

				R. Katz-Brull, P. T. Lavin, and R. E. Lenkinski Clinical Utility of Proton Magnetic Resonance Spectroscopy in Characterizing Breast Lesions J Natl Cancer Inst, August 21, 2002; 94(16): 1197 - 1203. [Abstract] [Full Text] [PDF]

				G. F. Tillman, S. G. Orel, M. D. Schnall, D. J. Schultz, J. E. Tan, and L. J. Solin Effect of Breast Magnetic Resonance Imaging on the Clinical Management of Women With Early-Stage Breast Carcinoma J. Clin. Oncol., August 15, 2002; 20(16): 3413 - 3423. [Abstract] [Full Text] [PDF]

				L. Liberman, E. A. Morris, M. J.-Y. Lee, J. B. Kaplan, L. R. LaTrenta, J. H. Menell, A. F. Abramson, S. M. Dashnaw, D. J. Ballon, and D. D. Dershaw Breast Lesions Detected on MR Imaging: Features and Positive Predictive Value Am. J. Roentgenol., July 1, 2002; 179(1): 171 - 178. [Abstract] [Full Text] [PDF]

				R. R. Davies Variations in Breast MR Imaging Protocol Radiology, May 1, 2002; 223(2): 586 - 586. [Full Text] [PDF]

				N. R. Jagannathan, V. Seenu, M. Kumar, D. K. W. Yeung, H. S. Cheung, and G. M. K. Tse Potential of in Vivo Proton MR Spectroscopy in the Assessment of Breast Lesions without the Use of Contrast Agent * Dr Yeung and colleagues respond: Radiology, April 1, 2002; 223(1): 281 - 282. [Full Text] [PDF]

				L. Liberman, S. L. Goodstine, D. D. Dershaw, E. A. Morris, L. R. LaTrenta, A. F. Abramson, and K. J. V. Zee One Operation After Percutaneous Diagnosis of Nonpalpable Breast Cancer: Frequency and Associated Factors Am. J. Roentgenol., March 1, 2002; 178(3): 673 - 679. [Abstract] [Full Text] [PDF]

This Article Abstract Figures Only Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Orel, S. G. Articles by Schnall, M. D. Search for Related Content PubMed PubMed Citation Articles by Orel, S. G. Articles by Schnall, M. D.