RESUMO
Objective To investigate the atypical CT ,MRI findings of pancreatic neuroendocrine tumors (PanNETs) ,in order to improve diagnosis .Methods The clinical ,imaging and pathological data of 6 patients with PanNETs confirmed by pathology were analyzed retrospectively .Results In all 6 cases ,2 lesions were located in the pancreatic head ,3 lesions in the pancreatic body ,and 1 lesion in the pancreatic tail .There were 2 functional PanNETs with an average size of 2 .1 cm × 2 .6 cm ,which showed homogeneous density or signal .There were 4 nonfunctional PanNETs with an average size of 2 .7 cm × 4 .3 cm ,one of which had calcification ,and two of which had obviously cystic change ,including intracapsular bleeding in one case .Contrast‐enhanced examinations showed that all 6 lesions had mild or moderate enhancement .Three lesions were manifested as relatively intense enhancement in the arterial and portal venous phase ,but decreased enhancement in the delayed phase ,including annular envelope enhancement in one case .Two le‐sions were manifested as progressive enhancement .The last case was manifested as inwardly filled enhancement .Three lesions had unclear boundaries ,while one lesion had splenic vein invasion .Two cases accompanied with mild expansion of the common bile duct or pancreatic duct .Conclusion PanNETs can be ma+nifested as atypical findings such as obviously cystic changes ,and(or) mild to moderate enhancement .It is suggested that the atypical imaging findings of PanNETs should be recognized well to improve the diag‐nostic accuracy .