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Gastrointestinal Imaging |
1 From the Departments of Radiology (G.d.A., M.P.V., V.V.) and Pathology (A.C., P.B.), INSERM Unité 773 CRB3 (A.C., P.B., V.V.), and the Fédération Médico Chirurgicale (P.H., O.H., A.S., P.R.), Beaujon Hospital, 100 boulevard général Leclerc, 92110 Clichy La Garenne, France; and Department of Epidemiology, Biostatistics and Clinical Research, Hôpital Bichat, APHP, University of Paris 7, Paris, France (S.B.). Received February 12, 2008; revision requested May 1; revision received June 17; accepted July 3; final version accepted July 22. Supported by a grant from the Roche Foundation. Address correspondence to G.d.A. (e-mail: gdassignies{at}gmail.com).
Purpose: To prospectively correlate multidetector computed tomographic (CT) perfusion measurement of pancreatic endocrine tumors with tumor microvascular density (MVD) assessed by using histologic techniques and to determine whether perfusion CT parameters differ between tumor grades.
Materials and Methods: Institutional review board approval and informed consent were obtained. Thirty-six patients (15 men, 21 women; mean age, 53 years; range, 18–78 years) with resectable pancreatic endocrine tumors underwent presurgical dynamic perfusion CT. Twenty-eight (78%) of 36 patients were included in the study group; eight were excluded because of artifacts that were not compatible with perfusion postprocessing. Multidetector CT perfusion data were analyzed to calculate tumor and normal pancreatic blood flow, blood volume, mean transit time, and permeability–surface area product. Multidetector CT perfusion parameters were compared with intratumoral MVD by using the Spearman correlation coefficient and with World Health Organization (WHO) classification, tumor size, tumor proliferation index, hormonal profile, and presence of metastases by using Mann-Whitney tests.
Results: High correlation (r = 0.620, P < .001) was observed between tumor blood flow and intratumoral MVD. Blood flow was significantly higher (P = .02) in the group of benign tumors (WHO 1) than in the groups of tumors of indeterminate prognosis (WHO 2) or well-differentiated carcinomas (WHO 3). Blood flow was significantly higher in tumors with a proliferation index of 2% or less (P = .005) and in those without histologic signs of microscopic vascular involvement (P = .008). Mean transit time was longer in tumors with lymph node (P = .02) or liver (P = .05) metastasis.
Conclusion: Perfusion CT is feasible in patients with pancreatic endocrine tumors and reflects MVD. Perfusion CT measurements are correlated with histoprognostic factors, such as proliferation index and WHO classification.
© RSNA, 2008