Abstract
A 76–year–old man with a history of left renal cell carcinoma, bladder cancer, and prostate cancer was found in plain computed tomography (CT) conducted as December 2007 postoperative follow–up to have a semicircular cystic pancreatic tail mass 28 mm in diameter. The lesion had grown to 40 mm in contrast–enhanced CT in March 2008. The partially filled cyst showed enhanced contrast comparable to that in the pancreatic parenchyma. Positron emission tomography (PET) showed FDG accumulation. Examinations for neuroendocrine tumor, renal cell carcinoma metastasis, retroperitoneal tumor, and pancreatic duct carcinoma showed no typical signs of these diseases. In April 2008 pancreatic tail resection, tissue examined histopathologically showed tumor cells with eosinophilic bodies and diastase–resistant PAS–positive small granules, yielding a diagnosis of pancreatic acinar cell carcinoma, a rare disease accounting for only 1–2% of pancreatic tumors. This cancer accompanied by a cyst as in our case, is highly atypical.
