Signal characteristic and enhancement patterns of pancreatic adenocarcinoma: evaluation with dynamic gadolinium enhanced MRI.
OBJECTIVE
To determine the signal characteristics and enhancement patterns of proven pancreatic adenocarcinomas at 1.5 T and to compare these results with contrast enhanced computed tomography (CECT).


METHODS
Twenty-five patients, mean age 73 years, with proven pancreatic adenocarcinoma were imaged at 1.5 T using in- and opposed-phase, gradient-echo (GRE), T1-weighted sequences, T2 weighting using either a short tau inversion recovery (STIR) or frequency selective, fat-suppressed turbo spin echo (TSE) sequence, and with a three-dimensional (3D), fat-suppressed, GRE T1 sequence before, during the arterial, venous, and equilibrium phases after Gadolinium administration. Fourteen of the 25 patients underwent CECT. Magnetic resonance imaging (MRI) examinations were evaluated by two observers in consensus for size, signal characteristics, and enhancement patterns, and the results were compared with CECT.


RESULTS
The mean size of pancreatic adenocarcinomas was 32 mm. On unenhanced T1-weighted images, 12 of 25 lesions (48%) were hypointense, 13 (52%) were isointense. On STIR/T2, 11 of 25 (44%) pancreatic adenocarcinomas were hyperintense, 14 (56%) were isointense. All 25 (100%) adenocarcinomas were hypointense during the arterial phase. Twenty (80%) and 17 (68%) remained hypointense in the venous phase and equilibrium phases, respectively. In seven of 14 (50%) cases, the pancreatic mass was iso-attenuating to the pancreatic parenchyma during both the pancreatic and venous phases of CECT.


CONCLUSIONS
The results of the present study showed that all 25 pancreatic adenocarcinomas were hypointense to pancreatic parenchyma during the arterial phase. Moreover, MRI may be useful in patients with a high suspicion of pancreatic carcinoma that is not visualized during CECT.
Department of Radiology, Abdominal Imaging, NYU School of Medicine, Tisch Hospital, New York, NY 10016, USA.
H
H
Chandarana
J
J
Babb
M
M
Macari
D000230:Adenocarcinoma / Q000175:diagnosis*; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010190:Pancreatic Neoplasms / Q000175:diagnosis*; D012189:Retrospective Studies
D003287:Contrast Media; D019786:Gadolinium DTPA