AB099. P073. Clinicopathological analysis of cystic pancreatic carcinoma in 31 cases

Background: To summarize the characteristics of cystic pancreatic adenocarcinoma, and to improve the general understanding of the imaging and pathologic features, and other pancreatic cystic diseases are compared for differential diagnosis.

Methods: This study included patients treated in the Department of General Surgery, Peking University Third Hospital, from Jan 2000 to Dec 2012 due to pancreatic neoplasm. The imaging data and diagnostic imaging reports showed that in the cases that were diagnosed as pancreatic carcinoma there were cystic performance and “cystic mass”. The characteristics of these patients were collected, such as gender, age, major symptoms, tumor marker tests, imaging diagnosis, preoperative clinical diagnosis, surgical operation, gross specimen and pathological diagnosis. Further analyses were conducted to find out the common features of cystic pancreatic carcinoma. The imaging features were compared with gross specimen; and the causes of cystic imaging findings were analyzed; other pancreatic cystic diseases were also listed and discussed in our study to avoid misdiagnosis, differential ways among them were also explored.

Results: Among the 398 cases of pancreatic carcinoma, 31 patients had cystic characteristics, accounting for 7.8%. Imaging results found that there were low (no) echo, or low-density mass, but most of the reports for preoperative diagnosis were vague, with only 4 cases diagnosed as cystic pancreatic ductal adenocarcinoma. Thirty-one cases were all underwent surgical exploration. These cystic pancreatic carcinoma have a variety of performances, there is no uniform morphology. Based on preoperative imaging and gross pathological results, the cystic lesions were divided into the following three types: cystic-solid type (14 cases), cystic type (13 cases) and duct dilated type (4 cases). The cystic-solid lesions were primarily located in the head and body of pancreas, while the cystic lesions were commonly seen in the tail of pancreas. Pathological examination revealed that 24 cases were pancreatic ductal adenocarcinoma, which was moderately or poorly differentiated; and the other 7 cases were rare types of pancreatic carcinoma.

Conclusions: Pancreatic ductal adenocarcinoma and its variants may have cystic features. When analyzing preoperative imaging findings of pancreatic cystic mass, the characteristics of the cystic pancreatic ductal adenocarcinoma should be fully taken into account to make differential diagnosis.