BACKGROUND/AIMS: Pancreatic neuroendocrine tumors (PNET) are rare and manifest as functioning tumor (FT) or non-functioning tumor (NFT). Although malignant changes are observed in some cases, its prognosis is better than pancreatic cancer. We evaluated clinicoradiologic features and prognosis of FT and NFT. In addition, we tried to find the predictive factors for the recurrence of NFT after resection. METHODS: Between October 1994 and June 2004, we retrospectively evaluated the clinicopathologic features and prognosis of 12 cases of FT and 31 cases of NFT diagnosed by surgical pathology at single medical center in Korea. RESULTS: PNET included 6 insulinomas, 4 gastrinomas, 1 glucagonoma, 1 somatostatinoma and 31 NFT. The major clinical manifestations were neuroglycopenic symptoms (100%) in insulinoma, abdominal ulcer symptoms (75%) in gastrinoma, dermatitis (100%) in glucagonoma, steatorrhea (100%) in somatostatinoma, and abdominal discomfort or pain (45%) in NFT. NFT was located more proximally when compared to FT (p=0.023). NFT showed more malignant (64.5%) behavior compared to FT (41.7%) despite the lack of statistical significance. Curative resections were done without postoperative death in 38 cases. Six cases of NFT (21.4%) and 1 case of FT (10%) recurred with an average of 26.5 months. In the recurrent NFT, the findings of diabetes mellitus (p=0.010), abnormal pancreatic duct (p=0.026), Whipple's operation (p=0.013) and tumor emboli (p=0.03) were more common than in non-recurrent NFT. CONCLUSIONS: FT and NFT showed different clinicoradiologic features. In addition, NFT should be monitored more carefully because of frequent recurrence.
Adult ; Diabetes Mellitus/pathology ; Female ; Humans ; Male ; Middle Aged ; Neoplastic Cells, Circulating/pathology ; Neuroendocrine Tumors/complications/*diagnosis ; Pancreatic Ducts/abnormalities/pathology ; Pancreatic Neoplasms/complications/*diagnosis ; Whipple Disease/complications

Nesidioblastosis is a term used to describe pathologic overgrowth of pancreatic islet cells. It also means maldistribution of islet cells within the ductules of exocrine pancreas. Generally, nesidioblastosis occurs in beta-cell and causes neonatal hyperinsulinemic hypoglycemia or adult noninsulinoma pancreatogenous hypoglycemia syndrome. Alpha-cell nesidioblastosis and hyperplasia is an extremely rare disorder. It often accompanies glucagon-producing marco- and mircoadenoma without typical glucagonoma syndrome. A 35-year-old female was referred to our hospital with recurrent acute pancreatitis. On radiologic studies, 1.5 cm sized mass was noted in pancreas tail. Cytological evaluation with EUS-fine-needle aspiration suggested serous cystadenoma. She received distal pancreatectomy. The histologic examination revealed a 1.7 cm sized neuroendocrine tumor positive for immunohistochemical staining with glucagon antibody. Multiple glucagon-producing micro endocrine cell tumors were scattered next to the main tumor. Additionally, diffuse hyperplasia of pancreatic islets and ectopic proliferation of islet cells in centroacinar area, findings compatible to nesidioblastosis, were seen. These hyperplasia and almost all nesidioblastic cells were positive for glucagon immunochemistry. Even though serum glucagon level still remained higher than the reference value, she has been followed-up without any evidence of recurrence or hormone related symptoms. Herein, we report a case of alpha-cell nesidioblastosis and hyperplasia combined with glucagon-producing neuroendocrine tumor with literature review.
Adult ; Chromogranin A/blood ; Female ; Glucagon/*metabolism ; Glucagon-Secreting Cells/metabolism ; Humans ; Hyperplasia/complications/*diagnosis ; Islets of Langerhans/metabolism/ultrasonography ; Nesidioblastosis/complications/*diagnosis ; Neuroendocrine Tumors/complications/*diagnosis/pathology ; Pancreas/*pathology ; Tomography, X-Ray Computed