High-and low-grade pancreatic neuroendocrine tumors:CT and MRI features / 天津医药

ABSTRACT

Objective To analyze the CT and MRI features of high and low grade pancreatic neuroendocrine tumors (PNET). Methods The clinical, imaging and pathological data of 32 patients with PNET collected from January 2011 to May 2017 were retrospectively analyzed.There were 21 cases with low grade PNET(G1,G2)and 11 cases with high grade PNET(G3).All of the 32 patients were performed with CT or MRI examination before operation,and pathology analysis was confirmed after operation.The imaging findings were compared between high-and low-grade PNET groups.Results In 32 patients,31 cases were with single lesion,only 1 case with two lesions.Twelve cases were in G1,9 cases in G2 and 11 cases in G3.Lesion location10 lesions were in pancreatic head,10 lesions in body and 12 lesions in tail.Lesion shape19 lesions were round,and 13 lesions were irregular.Lesion internal components16 cases were solid lesion,14 cases were as a cystic-solid lesion and 2 cases were cystic lesion.Calcification was found in 5 cases.Pancreatic bile tract dilatation was found in 3 cases(both were G3).The other organs or lymph gland metastasis were found in 4 cases(both were G3),in which 2 cases were with liver metastasis, 2 cases with lymphatic metastasis. High-grade PNET was usually located in the head of the pancreas,tumors were large in size,and the shape was often irregular,showing low enhancement on enhanced CT or MRI, which can be accompanied by dilation of the pancreatic bile tract and other organs or lymph node metastasis. Conclusion High-grade and low-grade PNET shows certain imaging characteristics, such as tumor diameter, shape, location, internal components,enhancement pattern,pancreatic bile tract dilatation and metastases features,which has important value for the forecast of preoperative pathology grade of PNET.