Imaging characteristics of pancreatic perivascular epithelioid cell tumor: analysis of 2 cases and literature review

Objective To evaluate the imaging and clinicopathological characteristics of pancreas perivascular epithelioid cell tumors (PEComa). Methods The clinical data of patients with pancreatic PEComa admitted in Changhai Hospital of Navy Medical University from Nov 2013 to Nov 2017 were retrospectively analyzed. Related literature on PEComa were searched and the image and clinicopathological characteristics were investigated. Results Two pancreatic PEComa patients were admitted in Changhai Hospital. Twenty-nine PEComa patients were reported in previous literature. A total of 31 cases were detected, including 3 men and 27 women. The onset age of the patients ranged from 17-74 years old with a mean of 48 years old. The lesions were located at the pancreatic head and neck in 20 cases, and at the pancreatic body and tail in 11 cases. 27 cases had a single lesion, and 4 cases had multiple lesions. Tumor diameter ranged from 1.0-11.5 cm with a mean of 4.1 cm. The cystic solid of the lesions was recorded in 23 patients, and 18 cases had solid mass. Pancreatic duct dilation was reported in 21 patients and 14 of them did not have pancreatic duct dilation. Enhancement mode of the lesions was examined in 21 patients, and the enhancement degree of the lesions were higher than that of the pancreas in 16 cases. Conclusions PEComa has a certain imaging characteristic, which could help obtain a preoperative diagnosis. Key words: Perivascular epithelioid cell tumor; Computed Tomography; Magnetic resonance imaging; Diagnosis; Differential