OBJECTIVE: We sought to describe the CT and MRI features of pure acinar cell carcinoma of the pancreas in adults.
MATERIALS AND METHODS: Eleven patients (six women and five men; mean age, 64 years) with acinar cell carcinoma, documented by pathologic examination of resected specimens, underwent CT (n = 9) or MRI (n = 2) examinations. Two radiologists evaluated imaging studies and determined, by consensus, the following data for each tumor: size, location, mar-gination, internal density or signal intensity, and contrast enhancement pattern. In addition, they assessed the presence of calcification, pancreatic or bile duct dilation, and metastases. Im-aging features were correlated with gross and microscopic pathologic features of the tumors.
RESULTS: Masses were distributed throughout the pancreas (head, n = 5; body, n = 2; and tail, n = 4). The mean largest dimensions were 6.0 x 5.3 cm (range, from 2x1.7 to 15x11 cm). Tumors were oval (n = 5), round (n = 4), or lobular (n = 2). Ten (91%) masses were well marginated; nine (82%) were exophytic. Five (45%) masses enhanced homogeneously; the remaining tumors contained cystic areas. All masses enhanced less than the surrounding pancreas. Three (27%) masses contained calcifications. Four (80%) masses invaded the duodenum. Common bile and pancreatic duct dilatation was present in two and three patients, respectively. One patient had metastatic liver disease at presentation.
CONCLUSION: Pure acinar cell carcinoma of the pancreas is usually an exophytic, oval or round, well-marginated, and hypovascular mass on CT and MRI. It typically is completely solid when small and contains cystic areas due to necrosis when large.
