Abstract:

Objective To analyze the clinicopathological features of pancreatic intraductal oncocytic papillary neoplasm (IOPN). Methods Five cases with pancreatic IOPN were in Ruijin Hospital including 3 female and 2 male, and the average age (60.0±10.4) years old. The clinical features combined with gross and microscopic pathology, immunophenotype and prognosis were analyzed. Results Two cases had abdominal pain including 1 case losing 5 kg during the period of 6 months. Three patients were found on physical examination. Pancreatic tumor in 2 cases located at the head, in 3 cases at the head and the body, the neck, and the body, respectively. The test showed serological CA724 elevated in 1 case, and other serological indexes were normal. The gross pathology showed that the tumor was multilocular cystic, cystic solid or solid. The solid area was gray-white, fragile, and the inner wall of the cyst was smooth or with papillary protrusions. The microscopic pathology showed that the tumor was ductal growth with complex branched papillary structure in the capsule. The tumor cells lining the papilla had eosinophilic granules, and the cell was atypia and contained typical nucleolus. Goblet cells could be seen among tumor cells. Mucus secretion was present and without significance. Immunohistochemistry showed cytokeratin 7 positive (3/4), MUC1 and MUC6 positive (4/4), MUC5AC positive (3/3), hepatocyte antigen (Hep Par 1) positive (3/4). CK20 or MUC2 in individual tumor cells were positive and SYN and CgA negative (2/2). There were 4 cased with following-up without recurrence or metastasis in any case. Conclusions IOPN is a rare pancreatic epithelial tumor with low malignancy, which is divided from pancreatic intraductal papillary mucinous neoplasms, and has unique clinical and pathological characteristics. Further study with recognition is needed for rare disease of IOPN.

Key words: Pancreas, Intraductal oncocytic papillary neoplasm, Pathology, Immunohistochemistry