Two synchronous somatostatinomas of the duodenum and pancreatic head in one patient

Clinicopathological Data and Treatment Modalities for Pancreatic Somatostatinomas

BACKGROUND/AIM

Somatostatinomas (SSomas) constitute a rare neuroendocrine tumor. The purpose of this study was to evaluate the current published literature about pancreatic SSomas and report epidemiologic and clinicopathologic data for this entity.

PATIENTS AND METHODS

A combined automated and manual systematic database search of the literature was performed using electronic search engines (Medline PubMed, Scopus, Ovid and Cochrane Library), until February 2020. Statistical analysis was performed using the R language and environment for statistical computing.

RESULTS

Overall, the research revealed a total of 36 pancreatic SSoma cases. Patient mean age was 50.25 years. The most common pancreatic location was the pancreatic head (61.8%). The most frequent clinical symptom was abdominal pain (61.1%). Diagnostic algorithm most often included Computed Tomography and biopsy; surgical resection was performed in 28 cases. Out of the 36 cases, 22 had been diagnosed with a metastatic tumor and metastasectomy was performed in 6 patients with a worse overall survival (OS) (p=0.029). In total, OS was 47.74 months.

CONCLUSION

Patients with metastatic disease did not benefit from metastasectomy, but the sample size was small to reach definite conclusions. However, further studies with longer follow-up are needed for a better evaluation of these results.

Cystic pancreatic neuroendocrine tumors (cPNETs): a systematic review and meta-analysis of case series

Cystic pancreatic neuroendocrine tumors represent 13% of all neuroendocrine tumors. The aim of this study is to analyze the phenotype and biologic behavior of resected cystic neuroendocrine tumors. A systematic review and meta-analysis were conducted until September 2016 using a search in Medline, Scopus, and EMBASE with the terms "cystic pancreatic endocrine neoplasm", "cystic islets tumors" and "cystic islets neoplasms". From the 795 citations recovered 80 studies reporting on 431 patients were selected. 87.1% (n = 387) were sporadic tumors and 10.3% (n = 40) corresponded to multiple endocrine neoplasia endocrine type 1. Were diagnosed incidentally 44.6% (n = 135). Cytology was found to have a sensitivity of 78.5%. Were non-functional tumors 85% (n = 338), and among the functional tumors, insulinoma was the most frequent. According to the European Neuroendocrine Tumor Society staging, 87.8% were limited to the pancreas (I-IIb), and 12.2% were advanced (III-IV). Disease-free survival at 5 years in stages (I-IIIa) and (IIIb-IV) was 91.5% and 54.2%, respectively; and was significantly lower (p = 0.0001) in functional tumors. In patients with multiple endocrine neoplasia there was a higher incidence of functional (62.5%) and multifocal (28.1%) tumors. Disease-free survival at 5 and 10 years was 60%. Cystic pancreatic neuroendocrine tumors exhibit phenotypical characteristics which are different to those of solid neuroendocrine tumors.

Somatostatinoma of the Ampulla: An Incidental Postoperative Finding Following Colorectal Cancer Resection

Somatostatinoma of the gastrointestinal tract is a rare finding, especially arising from the ampulla of Vater. We present a man recently diagnosed with rectal adenocarcinoma who was found on imaging to have an ampullary mass. Histology and immunohistochemical staining of the biopsied tissue were consistent with a nonfunctioning somatostatinoma. The patient had neurofibromatosis, which have been reported in patients with ampullary somatostatinomas. Our case highlights the importance of gastrointestinal findings in those with underlying genetic conditions.

Gastric somatostatinoma: an extremely rare cause of upper gastrointestinal bleeding

A 49-year-old woman presented with chronic abdominal discomfort, significant weight loss, and chronic intermittent diarrhea. She suddenly developed massive upper gastrointestinal bleeding and was referred for further treatment. Endoscopy indicated a large mass in the upper gastric body with antral and duodenal bulb involvement. Endosonography showed a large well-defined isoechoic gastric subepithelial mass with multiple intra-abdominal and peripancreatic lymphadenopathy, suspected to be malignant on the basis of fine needle aspiration cytology. The tumor was surgically removed, and histopathology showed typical characteristics of a neuroendocrine tumor. On the basis of immunohistochemical staining, somatostatinoma, a rare neuroendocrine tumor, was diagnosed. Gastrointestinal bleeding is a rare presentation and the stomach is an uncommon tumor location.