Colloid carcinoma arising from intraductal papillary mucinous neoplasm of pancreas: imaging features and differentiation from ductal adenocarcinoma / 中华放射学杂志

ABSTRACT

Objective:To investigate the imaging features of colloid carcinoma arising from intraductal papillary mucinous neoplasm (IPMN) of pancreas and the differentiation features from ductal adenocarcinoma arising from IPMN, using the pathological findings as the reference.Methods:Twenty-four patients with pathologically confirmed colloid carcinoma from November 2013 to January 2020 in Changhai Hospital, Navy Medical University were included in this study. The clinical manifestations, imaging features and pathological data were retrospective reviewed. Thirty patients of ductal adenocarcinoma arising from IPMN confirmed by pathology were selected as the control group. CT and MRI features of two groups were blindly analyzed by two radiologists, including the lesions location, type of IPMN, size, components, density or signal, calcification, dilation and size of the main pancreatic duct (MPD), pancreatic parenchymal atrophy, fistula formation. The χ 2 test or Fisher exact probability was used to compare the imaging features between the two groups. Results:As for IPMN with colloid carcinoma, 16 cases were located in the head of the pancreas, 7 cases in the body and tail of the pancreas, and 1 case showed diffused changes of the pancreas. Mass was found in twenty-two cases, with the size of 54.5 (29) mm. Nineteen cases were solid-cystic, 4 were cystic and 1 was solid. Thick wall and internal separation with mild enhancement were displayed. Five cases were found with high signal on T 1WI. Thirteen cases had calcification and 2 cases had gas in the tumor. The size of MPD was (13±5) mm. Pancreatic parenchymal atrophy was found in 21 cases and fistula formation was found in 8 cases. The mass size of IPMN with colloid carcinoma was significantly greater than that of IPMN with ductal adenocarcinoma [31 (16) mm, Z=-3.758, P<0.001]. Solid-cystic mass was more found in IPMN with colloid carcinoma and solid mass was more found in IPMN with ductal adenocarcinoma ( P<0.001). Calcification ( P=0.001), fistula formation ( P=0.031), and high signal on T 1WI ( P=0.034) were more found in IPMN with colloid carcinoma than IPMN with ductal adenocarcinoma. Conclusion:Compared with IPMN with ductal adenocarcinoma, the solid-cystic mass, calcification, fistula formation and high signal on T 1WI were more commonly found in IPMN with colloid carcinoma.