Clinicopathological Data and Treatment Modalities for Pancreatic Somatostatinomas

Abstract

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.

Surgical Management of Pancreatic Neuroendocrine Tumors

“…Reduction of tumor burden reduction (debulking) may be considered for symptomatic control if feasible [ 68 ]. The majority of somatostatinomas are malignant [ 70 , 71 ], and localized disease should undergo resection [ 69 , 72 ]. Smaller somatostatinomas (less than 2 cm) can be addressed via formal surgical resection or enucleation [ 72 ].…”

“…The majority of somatostatinomas are malignant [ 70 , 71 ], and localized disease should undergo resection [ 69 , 72 ]. Smaller somatostatinomas (less than 2 cm) can be addressed via formal surgical resection or enucleation [ 72 ]. Curative-intent resection likely requires a pancreaticoduodenectomy, given the proclivity of the tumor arising in the head of the pancreas [ 69 ].…”

“…Curative-intent resection likely requires a pancreaticoduodenectomy, given the proclivity of the tumor arising in the head of the pancreas [ 69 ]. Meta-analysis on resection of somatostatinoma metastases has demonstrated no survival benefit [ 72 ]. Similar to the surgical management of glucagonoma and VIPomas, the data specific to somatostatinomas is lacking and reliant on other functional PNET studies.…”

An Insight on Functioning Pancreatic Neuroendocrine Neoplasms

“…It represents 4% of PanNENs with an estimated incidence of one case per 40 million person-years with a female predominance (2:1) [75]. Somatostatinoma is often associated in the context of familiar syndromes, including MEN1, VHL and NF1; moreover, it is a frequent tumor type in the duodenum and rare in the pancreas [75,76].…”

“…It represents 4% of PanNENs with an estimated incidence of one case per 40 million person-years with a female predominance (2:1) [75]. Somatostatinoma is often associated in the context of familiar syndromes, including MEN1, VHL and NF1; moreover, it is a frequent tumor type in the duodenum and rare in the pancreas [75,76]. In less of 10% of patients, somatostatinoma can be associated with clinical manifestations of inappropriate somatostatin secretion, thereby causing the classic triad of somatostatinoma syndrome (diabetes/glucose intolerance, cholelithiasis and diarrhea/steatorrhea) [75].…”