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 Ljumanovic, R. Articles by Castelijns, J. A. Search for Related Content PubMed PubMed Citation Articles by Ljumanovic, R. Articles by Castelijns, J. A.

MR Imaging Predictors of Local Control of Glottic Squamous Cell Carcinoma Treated with Radiation Alone¹

¹ From the Departments of Radiology (R.L., B.S., J.A.C.), Clinical Epidemiology and Biostatistics (D.L.K.), and Otolaryngology/Head and Neck Surgery (C.R.L.), VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, the Netherlands; Department of Radiation Oncology, University Medical Center Groningen, Groningen, the Netherlands (J.A.L.); and Department of Radiology, Onze Lieve Vrouwe Gasthuis, Amsterdam, the Netherlands (M.v.W.). Received April 6, 2006; revision requested June 1; revision received July 19; accepted August 23; final version accepted November 10. Address correspondence to R.L. (e-mail: Redina.Ljumanovic{at}vumc.nl).

	ABSTRACT

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION ADVANCE IN KNOWLEDGE References

 
Purpose: To retrospectively evaluate the prognostic significance of magnetic resonance (MR) imaging–determined tumor parameters, especially the presence of cartilage invasion, regarding local control of glottic squamous cell carcinoma treated with radiation therapy (RT) alone.

Materials and Methods: The study was performed with the approval of our institutional review board; direct patient consent was waived. Pretreatment MR images of 118 patients aged 41–86 years (110 men, eight women) with glottic carcinoma treated with RT alone were reviewed for tumor involvement of specific laryngeal anatomic subsites (including laryngeal cartilage), tumor volume, and extralaryngeal tumor spread; these findings were compared with local control. Local control was defined as absence of a recurrence at the primary site for 2 years. Statistical significance of differences between curves for local control estimated with the Kaplan-Meier method was tested with log-rank test.

Results: Results of univariate analysis showed all MR imaging–determined parameters to be significant predictors of local control rate, compared with clinical parameters where T classification and vocal cord mobility were the only significant parameters associated with local control. Multivariate analysis (Cox regression model) of clinical and radiologic parameters revealed that hypopharyngeal extension (P = .04) and intermediate T2 signal intensity (SI) in cartilage similar to tumor SI (P < .001) were independent prognostic factors with regard to local control.

Conclusion: Intermediate T2 SI in cartilage, which may suggest cartilage invasion, and hypopharyngeal extension of tumor, predict greater likelihood of local failure, whereas high T2 SI, which may suggest inflammatory tissue in cartilage, predicts lower likelihood of local failure.

© RSNA, 2007

	INTRODUCTION

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION ADVANCE IN KNOWLEDGE References

 
Clinical tumor extension, and to some degree imaging findings, according to the TNM system, provide important information about the probability of local control of laryngeal carcinoma after radiation therapy (RT) with curative intent. Patients with advanced disease (eg, in the case of extensive cartilage invasion and/or extralaryngeal extension), comprise an unfavorable group for RT and are often advised to undergo laryngectomy (1). Combined chemo- and radiation therapy for advanced stages of laryngeal carcinoma with salvage surgery constitute a good alternative for primary surgery followed by postoperative RT (2–4).

Computed tomographic (CT) findings of the primary tumor have been described as potential effective predictors of local control of glottic carcinoma treated with RT alone (5–9). In several studies, a large CT-derived tumor volume was found to be a predictor of local failure (6,7,9). Pameijer et al (6) proposed that T3 glottic cancer with a CT-based tumor profile smaller than 3.5 cm³ and single or no laryngeal cartilage sclerosis may potentially be treated by RT with a curative intent. In other studies, the risk of tumor recurrence has been reported to increase with invasion of the preepiglottic and paraglottic spaces and subglottic extension, where primary tumor volume is an important predictor, but covariates reflecting deep tissue invasion seem to be even stronger predictors of local control in glottic cancer (5,8). The presence of extralaryngeal spread has also been recognized as an important prognostic factor regarding local control in the head and neck and was associated with higher rates of failure (10).

It is often suggested that cartilage involvement depicted at imaging precludes voice-sparing partial laryngectomy and is also a contraindication to RT, thus leaving total laryngectomy as the only alternative (11–13). Previous reports have shown that CT evidence of subtle cartilage invasion may not be a valid predictor of poor results with RT (5). CT is more specific, but less sensitive, than magnetic resonance (MR) imaging (12). As reviewed by Castelijns et al (14–16), pretreatment MR findings of tumor volume, especially in combination with the so-called abnormal signal intensity in cartilage seen on T1-weighted images, indicate an adverse prognosis with regard to tumor recurrence. To our knowledge, MR findings have not been studied regarding differences in T2 signal intensity (SI) in cartilage and its correlation with local outcome for glottic cancer after RT. Thus, the objective of our study was to retrospectively evaluate the prognostic importance of MR imaging–determined tumor parameters, especially the presence of cartilage invasion, regarding local control of glottic squamous cell carcinoma treated by RT alone.

	MATERIALS AND METHODS

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION ADVANCE IN KNOWLEDGE References

 
Patient Population
Patients eligible for this retrospective study were those with pathologically proved glottic squamous cell carcinoma, treated with RT alone between 1984 and 1999. All patients underwent pretreatment MR imaging. Patients with a previous history of laryngeal cancer or other malignant diseases in the head and neck region were excluded. The study was performed with the approval of our institutional review board; direct patient consent was waived.

One hundred eighteen patients, aged 41–86 years (median, 64 years) met the inclusion criteria: 110 men (93%) and eight women (7%). Seventy-seven patients (65.3%) had normal vocal cord mobility, 30 (25.4%) had impaired cord mobility and 11 (9.3%) had no cord mobility. Stage of disease in all patients was clinically assessed according to International Union Against Cancer staging system 2002 (17). Finally, the classification was T1a in 10 patients (8.5%), T1b in 29 patients (24.5%), T2 in 59 patients (50.0%), T3 in 10 patients (8.5%), and T4 in 10 patients (8.5%). Five patients with positive lymph nodes were clinically and according to MR imaging findings classified: T2N1 (n = 3), T3N1 (n = 1), and T4N1 (n = 1). Histopathologic examination of biopsy specimens showed well-differentiated squamous cell carcinoma in 28 patients (23.7%), moderately differentiated carcinoma in 69 patients (58.5%) and poorly differentiated carcinoma in 21 patients (17.8%).

MR Imaging
Before 1994, MR images were obtained by using a 0.6-T MR system (Gyroscan S5; Philips Medical Systems, Best, the Netherlands). From 1994 on, MR images were obtained with 91.0-T MR system (Impact; Siemens Medical Solutions, Erlangen, Germany). MR examinations were performed with an anterior surface neck coil. A multisection two-dimensional Fourier-transform spin-echo pulse sequence was used in all cases. In sagittal and transverse planes, a T1-weighted spin-echo technique (repetition time msec/echo time msec, 200–700/15) was applied. We also generated intermediate-weighted (1500/38) and T2-weighted (1500–4000/76–98) spin-echo MR images in the transverse plane at each corresponding level. Transverse planes were obtained parallel to the vocal cords. The acquisition of T1-weighted MR images was repeated four times for signal averaging, while intermediate-weighted and T2-weighted MR images were acquired twice. Gadolinium-based (contrast material) was not routinely used in these patients. A 4-mm section thickness was used, with a 1-mm intersection gap. The field of view was kept as small as possible (200 x 200 mm). Acquisition times varied from 3 to 6 minutes per sequence.

RT and Follow-up
The mean period between MR examination and start of RT was 28 days (range, 2–86 days). All patients were treated with a linear accelerator and 6-MeV photons. In T1- and small T2-stage lesions, the clinical target volume consisted of the thyroid cartilage and no field reductions were used. In the case of T3- and T4-stage tumors or T2-stage lesions with impaired mobility and/or tumor extension at the level of the false vocal cords, the primary clinical target volume included the gross tumor volume (GTV) with a margin of at least 1.5 cm, the thyroid cartilage, and the lymph nodes in levels II–IV on both sides of the neck. In the case of pathologic lymph nodes, the elective nodal area was extended to level Ib to V on both sides. The clinical target volume of the boost included the GTV with a 1-cm margin. Total RT dose for patients ranged from 58 to 74 Gy (mean, 64.5 Gy), by using 2.0–2.5 Gy per fraction. The fractionation schedule for the early stages of RT (ie, T1–T2N0) was 2.5 Gy per fraction, five times a week, to a total dose of 60.0–62.5 Gy. This policy was not changed during the inclusion period. Before 1998, different fractionation schedules were used for more advanced laryngeal carcinoma cases. After 1998, planning CT was implemented routinely in these cases and the fractionation schedule was standardized to 70 Gy, 2 Gy per fraction, and six fractions per week, including a second fraction on Friday afternoon with a concomitant boost technique. The interval between the first and second fractions on Friday was at least 6 hours.

Follow-up included indirect laryngoscopy at regular intervals every 2 months during the first 2 years after finishing RT and every 4 to 6 months thereafter, supplemented by direct laryngoscopy with biopsies as necessary. Imaging was not routinely performed. No patients were lost to follow-up. The follow-up period was designated as the total time of follow-up ending either at local recurrence, or at last patient contact without local recurrence with a minimum of 2 years (mean follow-up time, 33 months; range, 4–97 months).

Evaluation of MR Parameters
All pretreatment MR images were retrospectively reviewed and evaluated by two observers in consensus with 13 and 4 years experience of head and neck MR imaging. They were blinded to the identity of patients and their clinical records. The following MR imaging parameters were assessed: primary tumor volume; presence of supraglottic and subglottic extension and involvement to preepiglottic space; abnormal SI in or destruction of cartilage adjacent to tumor tissue (ie, abnormal SI in cartilage at the anterior commissure, thyroid cartilage, and/or cricoarytenoid cartilage; and extralaryngeal extension beyond these cartilages—see below); and hypopharyngeal extension.

Abnormal SI in thyroid cartilage with tumor extension into the anterior commissure was separately assessed from abnormal SI in the remaining part of thyroid cartilage without tumor extension to the anterior commissure.

Abnormal SI in the cricoarytenoid region was defined as abnormal SI in the cricoid or arytenoid cartilage around the cricoarytenoid joint.

Extralaryngeal extension beyond the cartilage adjacent to the anterior commissure was considered to have spread beyond the cartilaginous framework into contiguous soft tissues. Tumor involvement into the hypopharynx was described as invasion of the lateral wall of the piriform sinus and postcricoid area.

Tumor extension was assessed on T1-weighted MR images as an area of intermediate SI, in high contrast to high-SI fat and with a somewhat lower SI than that of muscular tissue (18). Abnormal SI in cartilage was diagnosed on the basis of combined use of T1- and T2-weighted MR images at corresponding levels. On T1-weighted MR images, the tumor showed intermediate SI with high contrast to high-SI bone marrow of ossified cartilage. Different degrees of T2 SI in the cartilage were evaluated (low vs intermediate vs high): low T2 SI, as nonossified cartilage; intermediate T2 SI in cartilage, as similar to tumor SI; and high T2 SI in cartilage, as higher than T2 SI of intralaryngeal tumor tissue. Glottic cancers showing abnormal SI in one of the cartilages (thyroid, cricoarytenoid, and thyroid at anterior commissure) on T1-weighted MR images and with intermediate SI on T2-weighted MR images in at least one of the involved cartilages were classified as tumors with intermediate T2 SI in cartilage similar to tumor SI.

From 1985 to 1994, MR examinations were redigitized by using a film scanner. After 1993, digital MR images were obtained directly. The tumor outlines were traced manually on T1-weighted MR images by one observer (R.L.) with use of a computerized image analysis tool that is available as part of our hospital's (VU University Medical Center) picture archiving and communication system (Centricity Radiology RA 600, version 6.1; GE Healthcare, Milwaukee, Wis). The volume of the tumor was calculated in cubic centimeters by multiplying the tumor areas by section thickness and intersection gap and was then summarized over all sections in which the tumor was present. In 16 of 118 patients, no soft-tissue abnormality could be detected on MR images because the tumor was too small. In the analyses, tumors in these patients were considered to have a volume of 0 cm³.

Statistical Analysis
To evaluate the effectiveness of RT in local control, histologically proved local recurrences during follow-up were considered local failures. Local control was calculated from the 1^st day of RT. In the univariate analysis, the curves for local control were estimated by using the Kaplan-Meier method. To test the statistical significance of differences between curves, the log-rank test was used. A multivariate analysis using the Cox proportional hazards model was performed stepwise to identify clinical and radiologic covariates that were significantly associated with local control.

In the uni- and multivariate analyses, the following variables were entered stepwise into the model: sex (male vs female), age (64 years vs >64 years), T classification (T1a vs T1b vs T2 vs T3 vs T4), N classification (N0 vs N1), vocal cord mobility (normal vs impaired vs fixed), primary tumor volume (0.1–1.1 cm³ vs 1.1–3.0 cm³ vs >3.0 cm³), supraglottic extension (no vs yes), subglottic extension (no vs yes), involvement in preepiglottic space (no vs yes), abnormal SI in the thyroid at the anterior commissure (no vs yes), abnormal SI in thyroid and/or cricoarytenoid cartilage (no vs yes), extralaryngeal extension beyond cartilage at the anterior commissure (no vs yes), hypopharyngeal extension (no vs yes), and T2 SI in cartilage (low vs intermediate vs high). In the first step of the multivariate analysis, only the clinical parameters were entered. In the second step, the MR parameters were entered as well.

P values < .05 were designated for determining significant differences. All statistical calculations were performed by using software (SPSS, version 11.0; SPSS, Chicago, Ill).

	RESULTS

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION ADVANCE IN KNOWLEDGE References

 
MR Parameters
The mean tumor volume was 2.3 cm³ (median, 1.5 cm³; range, 0–11.0 cm³), and a significant correlation was found between T classification and tumor volume (P < .001).

In our population, extralaryngeal extension beyond thyroid and cricoid cartilage was not found. In 52 (44%) of 118 patients abnormal SI of cartilages adjacent to tumor tissue was found. Abnormal SI of cartilages in 17 (14%) of 118 patients was seen as higher than tumor T2 SI and was considered to be high T2 SI in cartilage. In 35 (30%) of 118 patients, the abnormal SI of at least one of the involved cartilages was similar to the tumor SI on T2-weighted MR images and was considered to be intermediate T2 SI in cartilage (Table 1, Figs 1 and 2).

View larger version (100K): [in this window] [in a new window] [Download PPT slide]   Figure 1a: Clinical stage T2 glottic carcinoma in 70-year-old patient. (a) Transverse T1-weighted MR image (600/15) at level of true vocal cord shows mass (arrow) with intermediate SI in left cord. Abnormal SI of the thyroid cartilage at anterior commissure is shown (arrowheads) as intermediate T1 SI. No tumor was noted in right vocal cord. (b) Transverse T2-weighted MR image (3000/98) at corresponding level demonstrates tumor tissue (arrow) with intermediate SI of tumor mass and of tumor extension compared with a, confirming abnormality in cartilage (arrowheads).

View larger version (115K): [in this window] [in a new window] [Download PPT slide]   Figure 1b: Clinical stage T2 glottic carcinoma in 70-year-old patient. (a) Transverse T1-weighted MR image (600/15) at level of true vocal cord shows mass (arrow) with intermediate SI in left cord. Abnormal SI of the thyroid cartilage at anterior commissure is shown (arrowheads) as intermediate T1 SI. No tumor was noted in right vocal cord. (b) Transverse T2-weighted MR image (3000/98) at corresponding level demonstrates tumor tissue (arrow) with intermediate SI of tumor mass and of tumor extension compared with a, confirming abnormality in cartilage (arrowheads).

View larger version (123K): [in this window] [in a new window] [Download PPT slide]   Figure 2a: Clinical stage T1b glottic carcinoma in 76-year-old patient. (a) Transverse T1-weighted MR image (400/15) at level of true cord shows mass (arrow) with intermediate SI in left cord. Abnormal intermediate SI of the thyroid cartilage at anterior commissure (arrowheads) is also seen. (b) Transverse T2-weighted MR image (2700/98) at corresponding level demonstrates tumor tissue (arrows) with intermediate T2 SI of tumor mass in high contrast to nonossified cartilage. Thyroid cartilage at anterior commissure shows higher T2 SI than does tumor tissue, which may suggest inflammatory tissue (arrowheads). (c) Transverse T1-weighted MR image (400/15) of same patient, one section lower, again shows tumor mass (large arrow) with intermediate SI in left cord with abnormal SI of thyroid cartilage at anterior commissure (arrowheads). The remaining part of thyroid cartilage on left side (small arrows) is also seen with intermediate SI. (d) Transverse T2-weighted MR image (2700/98) at corresponding level clearly demonstrates low SI in remaining part of thyroid cartilage on left side, suggesting nonossified cartilage. Consequently, the anterior two-thirds of thyroid lamina cartilage is nonossified. (Keys are as in c.)

View larger version (128K): [in this window] [in a new window] [Download PPT slide]   Figure 2b: Clinical stage T1b glottic carcinoma in 76-year-old patient. (a) Transverse T1-weighted MR image (400/15) at level of true cord shows mass (arrow) with intermediate SI in left cord. Abnormal intermediate SI of the thyroid cartilage at anterior commissure (arrowheads) is also seen. (b) Transverse T2-weighted MR image (2700/98) at corresponding level demonstrates tumor tissue (arrows) with intermediate T2 SI of tumor mass in high contrast to nonossified cartilage. Thyroid cartilage at anterior commissure shows higher T2 SI than does tumor tissue, which may suggest inflammatory tissue (arrowheads). (c) Transverse T1-weighted MR image (400/15) of same patient, one section lower, again shows tumor mass (large arrow) with intermediate SI in left cord with abnormal SI of thyroid cartilage at anterior commissure (arrowheads). The remaining part of thyroid cartilage on left side (small arrows) is also seen with intermediate SI. (d) Transverse T2-weighted MR image (2700/98) at corresponding level clearly demonstrates low SI in remaining part of thyroid cartilage on left side, suggesting nonossified cartilage. Consequently, the anterior two-thirds of thyroid lamina cartilage is nonossified. (Keys are as in c.)

View larger version (128K): [in this window] [in a new window] [Download PPT slide]   Figure 2c: Clinical stage T1b glottic carcinoma in 76-year-old patient. (a) Transverse T1-weighted MR image (400/15) at level of true cord shows mass (arrow) with intermediate SI in left cord. Abnormal intermediate SI of the thyroid cartilage at anterior commissure (arrowheads) is also seen. (b) Transverse T2-weighted MR image (2700/98) at corresponding level demonstrates tumor tissue (arrows) with intermediate T2 SI of tumor mass in high contrast to nonossified cartilage. Thyroid cartilage at anterior commissure shows higher T2 SI than does tumor tissue, which may suggest inflammatory tissue (arrowheads). (c) Transverse T1-weighted MR image (400/15) of same patient, one section lower, again shows tumor mass (large arrow) with intermediate SI in left cord with abnormal SI of thyroid cartilage at anterior commissure (arrowheads). The remaining part of thyroid cartilage on left side (small arrows) is also seen with intermediate SI. (d) Transverse T2-weighted MR image (2700/98) at corresponding level clearly demonstrates low SI in remaining part of thyroid cartilage on left side, suggesting nonossified cartilage. Consequently, the anterior two-thirds of thyroid lamina cartilage is nonossified. (Keys are as in c.)

View larger version (134K): [in this window] [in a new window] [Download PPT slide]   Figure 2d: Clinical stage T1b glottic carcinoma in 76-year-old patient. (a) Transverse T1-weighted MR image (400/15) at level of true cord shows mass (arrow) with intermediate SI in left cord. Abnormal intermediate SI of the thyroid cartilage at anterior commissure (arrowheads) is also seen. (b) Transverse T2-weighted MR image (2700/98) at corresponding level demonstrates tumor tissue (arrows) with intermediate T2 SI of tumor mass in high contrast to nonossified cartilage. Thyroid cartilage at anterior commissure shows higher T2 SI than does tumor tissue, which may suggest inflammatory tissue (arrowheads). (c) Transverse T1-weighted MR image (400/15) of same patient, one section lower, again shows tumor mass (large arrow) with intermediate SI in left cord with abnormal SI of thyroid cartilage at anterior commissure (arrowheads). The remaining part of thyroid cartilage on left side (small arrows) is also seen with intermediate SI. (d) Transverse T2-weighted MR image (2700/98) at corresponding level clearly demonstrates low SI in remaining part of thyroid cartilage on left side, suggesting nonossified cartilage. Consequently, the anterior two-thirds of thyroid lamina cartilage is nonossified. (Keys are as in c.)

View larger version (15K): [in this window] [in a new window] [Download PPT slide]   Figure 3: Graph shows that patients with glottic cancer with intermediate T2 SI in cartilage similar to tumor SI had a poor prognosis (n = 35, 2-year local control rate, 27%; 95% confidence interval: 20%, 34%) compared with patients with high T2 SI in cartilage (n = 17, 2-year local control rate, 84%; 95% confidence interval: 76%, 98%) and patients with low T2 SI in cartilage (n = 66, 2-year local control rate, 87%; 95% confidence interval: 75%, 93%).

	DISCUSSION

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION ADVANCE IN KNOWLEDGE References

According to our study, abnormal MR imaging SI patterns in cartilage (thyroid, cricoarytenoid, and thyroid at anterior commissure), without distinguishing different SIs as seen on T2-weighted images, were correlated with the risk of tumor recurrence. Univariate analyses demonstrated that SI abnormalities of cartilages were significantly associated with local control, but in multivariate analysis these findings did not reach significance when compared with more specific T2-weighted MR SI. These findings are in agreement with a preliminary report that stated that abnormal cartilage as shown on MR images increases the risk of local tumor recurrence (14). In other MR studies, tumor lesions have an increased risk of local failure after RT, especially when invasion of the thyroid cartilage is suggested (21).

In a previous CT study by Hermans et al (5), invasion of cartilage was not found to be an important predictor of local recurrence. While CT may enable detection of cartilage invasion, it may also fail because of the large variability of ossification patterns in the laryngeal cartilages. However, on the basis of results from a well-performed MR-histopathologic correlative study, Becker et al recently showed that SIs may enable differentiation between a tumor and inflammatory tissue in cartilage as found on T2-weighted spin-echo MR images (personal communication, Minerva Becker, MD, October 7, 2004). These findings are in agreement with those of the present study in which MR abnormalities classified as an intermediate T2 SI in cartilage similar to tumor SI were significantly associated with decreased local control.

The second most important prognostic factor in the present study was extension into the hypopharynx as assessed on MR images, which might be explained by a combination of large tumor volume and deep tissue extension. Hamilton et al (9) reported that hypopharyngeal involvement of a tumor would be useful as a potential indicator of local control. However, Hamilton et al also demonstrated a correlation between the tumor volume of T2- and T3-stage laryngeal glottic carcinoma and local control (9). In our study, MR imaging-determined tumor volume was significantly associated with local control in the univariate analysis, but in the multivariate analysis tumor volume was no longer an independent prognosticator. Both intermediate T2 SI in cartilage and hypopharyngeal tumor extension were potential confounders for the association between tumor volume and local control.

Another question arises regarding accurate volume measurement by using CT and/or MR. In a study by Daisne et al (22), tumor delineation at CT, MR, and fluorine 18-fluorodeoxyglucose positron emission tomography was compared and validated with the macroscopic surgical specimen when available. In that study, the results showed that in hypopharyngeal and laryngeal cancer, tumor volume on CT and MR images was substantially overestimated when compared with the volume assessed by using the surgical specimens, owing to the presence of peritumoral infiltration.

Consequently, MR findings (ie, hypopharyngeal extension and intermediate T2 SI in cartilage, which may suggest cartilage invasion) may be effective predictors for outcome of glottic carcinomas after definitive RT. In most patients with glottic carcinoma, nonsurgical organ preservation strategies are considered to be the best initial treatment approach. However, some selected subgroups of patients may have a higher risk of local failure than other patient groups. The results of our study showed that in patients with tumors with an intermediate SI pattern (suggesting cartilage invasion) in cartilages on T2-weighted MR images have a poor outcome with respect to local control, which was only 27% after 2 years. On the other hand, the results also showed that inflammatory changes possibly defined as a high T2 SI in cartilage indicate that the patients with these SI abormalities in cartilage should not automatically imply laryngectomy and could successfully be treated with nonsurgical treatment modalities.

One of the limitations of our study was that MR examinations were performed with different techniques (0.6- vs 1.0-T MR machines, digitization of older films). However, in our opinion, this did not influence contrast between tumor tissue and surrounding tissue and therefore did not interfere with adequate diagnosis of the extent of tumor tissue. Furthermore, we could not perform a pathologic analysis because our whole patient population was treated with definitive RT.

The results of our study confirmed that T2-weighted MR images may be helpful for determining outcome of primary RT in glottic carcinoma. Intermediate T2 SI in cartilage, which may suggest cartilage invasion, and hypopharyngeal extension of tumor predict a greater likelihood of local failure, whereas high T2 SI, which may suggest inflammatory tissue in cartilage, predicts a lower likelihood of local failure. A pathologic study would then determine whether this intermediate SI indeed represents a tumor.

	ADVANCE IN KNOWLEDGE

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION ADVANCE IN KNOWLEDGE References

 

• Intermediate T2 signal intensity (SI) in cartilage, which may be suggestive of cartilage invasion, and hypopharyngeal extension of tumor predict greater likelihood of local failure, whereas high T2 SI, which may be suggestive of inflammatory tissue in cartilage, predicts lower likelihood of local failure.
  

	ACKNOWLEDGMENTS

 
The authors thank Minerva Becker, MD, for providing information at the European Society of Head and Neck Radiology Meeting in 2004.

	FOOTNOTES

 

Abbreviations: GTV = gross tumor volume • RT = radiation therapy • SI = signal intensity

Authors stated no financial relationship to disclose.

Author contributions: Guarantors of integrity of entire study, J.A.L., C.R.L., J.A.C.; study concepts/study design or data acquisition or data analysis/interpretation, all authors; manuscript drafting or manuscript revision for important intellectual content, all authors; approval of final version of submitted manuscript, all authors; literature research, R.L., C.R.L., J.A.C.; clinical studies, C.R.L.; statistical analysis, R.L., J.A.L., D.L.K.; and manuscript editing, R.L., J.A.L., J.A.C.

	References

TOP ABSTRACT INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION ADVANCE IN KNOWLEDGE References

 

1. Million RR. The larynx...so to speak: everything I wanted to know about laryngeal cancer I learned in the last 32 years. Int J Radiat Oncol Biol Phys 1992;23:691–704.[Medline]
2. Allal AS, Nicoucar K, Mach N, Dulguerov P. Quality of life in patients with oropharynx carcinomas: assessment after accelerated radiotherapy with or without chemotherapy versus radical surgery and postoperative radiotherapy. Head Neck 2003;25:833–840.[CrossRef][Medline]
3. Hammond E, Berkey BA, Fu KK, et al. P105 as a prognostic indicator in patients irradiated for locally advanced head-and-neck cancer: a clinical/laboratory correlative analysis of RTOG-9003. Int J Radiat Oncol Biol Phys 2003;57:683–692.[CrossRef][Medline]
4. Bieri S, Bentzen SM, Huguenin P, et al. Early morbidity after radiotherapy with or without chemotherapy in advanced head and neck cancer: experience from four nonrandomized studies [in German]. Strahlenther Onkol 2003;179:390–395.[Medline]
5. Hermans R, Van den Bogaert W, Rijnders A, Doornaert P, Baert AL. Predicting the local outcome of glottic squamous cell carcinoma after definitive radiation therapy: value of computed tomography-determined tumour parameters. Radiother Oncol 1999;50:39–46.[CrossRef][Medline]
6. Pameijer FA, Mancuso AA, Mendenhall WM, Parsons JT, Kubilis PS. Can pretreatment computed tomography predict local control in T3 squamous cell carcinoma of the glottic larynx treated with definitive radiotherapy? Int J Radiat Oncol Biol Phys 1997;37:1011–1021.[CrossRef][Medline]
7. Murakami R, Furusawa M, Baba Y, et al. Dynamic helical CT of T1 and T2 glottic carcinomas: predictive value for local control with radiation therapy. AJNR Am J Neuroradiol 2000;21:1320–1326.[Abstract/Free Full Text]
8. Mukherji SK, Mancuso AA, Mendenhall W, Kotzur IM, Kubilis P. Can pretreatment CT predict local control of T2 glottic carcinomas treated with radiation therapy alone. AJNR Am J Neuroradiol 1995;16:655–662.[Abstract]
9. Hamilton S, Venkatesan V, Matthews TW, Lewis C, Assis L. Computed tomographic volumetric analysis as a predictor of local control in laryngeal cancers treated with conventional radiotherapy. J Otolaryngol 2004;33:289–294.[Medline]
10. Leemans CR, Tiwari R, Nauta JJ, van der Waal I, Snow GB. Recurrence at the primary site in head and neck and the significance of neck lymph node metastases as a prognostic factor. Cancer 1994;73:187–190.[CrossRef][Medline]
11. Becker M. Neoplastic invasion of laryngeal cartilage: radiologic diagnosis and therapeutic implications. Eur J Radiol 2000;33:216–229.[CrossRef][Medline]
12. Castelijns JA, Becker M, Hermans R. Impact of cartilage invasion on treatment and prognosis of laryngeal cancer. Eur Radiol 1996;6:156–169.[Medline]
13. Tart RP, Mukherji SK, Lee WR, Mancuso AA. Value of laryngeal cartilage sclerosis as a predictor of outcome in patients with stage T3 glottic cancer treated with radiation therapy. Radiology 1994;192:567–570.[Abstract/Free Full Text]
14. Castelijns JA, van den Brekel MW, Tobi H, et al. Laryngeal carcinoma after radiation therapy: correlation of abnormal MR imaging signal patterns in laryngeal cartilage with the risk of recurrence. Radiology 1996;198:151–155.[Abstract/Free Full Text]
15. Castelijns JA, van den Brekel MW, Smit EM, et al. Predictive value of MR imaging–dependent and non–MR imaging–dependent parameters for recurrence of laryngeal cancer after radiation therapy. Radiology 1995;196:735–739.[Abstract/Free Full Text]
16. Castelijns JA, Golding RP, van Schaik C, Valk J, Snow GB. MR findings of cartilage invasion by laryngeal cancer: value in predicting outcome of radiation therapy. Radiology 1990;174:669–673.[Abstract/Free Full Text]
17. Sobin LH, Wittekind Ch. TNM classification of malignant tumors. International Union Against Cancer. 6th ed. New York, NY: Wiley-Liss, 2002; 36–42.
18. Castelijns JA, Kaiser MC, Valk J, Gerritsen GJ, van Hattum AH, Snow GB. MR imaging of laryngeal cancer. J Comput Assist Tomogr 1987;11:134–140.[Medline]
19. Becker M, Zbaren P, Laeng H, Stoupis C, Porcellini B, Vock P. Neoplastic invasion of the laryngeal cartilage: comparison of MR imaging and CT with histopathologic correlation. Radiology 1995;194:661–669.[Abstract/Free Full Text]
20. Zbaren P, Becker M, Lang H. Staging of laryngeal cancer: endoscopy, computed tomography and magnetic resonance versus histopathology. Eur Arch Otorhinolaryngol 1997; 254(suppl 1): S117–S122.
21. Murakami R, Baba Y, Furusawa M, et al. Early glottic squamous cell carcinoma. Predictive value of MR imaging for the rate of 5-year local control with radiation therapy. Acta Radiol 2000;41:38–44.
22. Daisne JF, Duprez T, Weynand B, et al. Tumor volume in pharyngolaryngeal squamous cell carcinoma: comparison at CT, MR imaging, and FDG PET and validation with surgical specimen. Radiology 2004;233:93–100.[Abstract/Free Full Text]

This article has been cited by other articles:

				H. D. Curtin The "Evil Gray": Cancer and Cartilage Radiology, November 1, 2008; 249(2): 410 - 412. [Full Text] [PDF]

				M. Becker, P. Zbaren, J. W. Casselman, R. Kohler, P. Dulguerov, and C. D. Becker Neoplastic Invasion of Laryngeal Cartilage: Reassessment of Criteria for Diagnosis at MR Imaging Radiology, November 1, 2008; 249(2): 551 - 559. [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 Ljumanovic, R. Articles by Castelijns, J. A. Search for Related Content PubMed PubMed Citation Articles by Ljumanovic, R. Articles by Castelijns, J. A.