Prevalence of Neuroendocrine Tumors in the Gastrointestinal and Hepatobiliary Systems

Abstract

Background: Carcinoid tumors are the most common neuroendocrine tumors. In recent years, these tumors have had an increase<br />in incidence, which is probably due to a higher number of them being incidentally found as a result of the rise of preventive<br />medicine.<br />Objectives: This study aimed to analyze a series of digestive carcinoid tumors detected by conventional endoscopy and/or echoendoscopy<br />to evaluate the prevalence of those located in the colon and rectum, and subsequently make a comparison with data available<br />in the literature.<br />Methods: In this retrospective, multicenter study (two centers), the clinical records of 100 white patients with more than 100 digestive<br />carcinoid tumors (some multiple) diagnosed from 1994 to 2018 were reviewed.<br />Results: The mean age of presentation was 52 years and 57% of the patients were men. The mean tumor size was 10 mm. The localization<br />of the tumors was: stomach 43% (n = 43); duodenum 5% (n = 5); intestine 8% (n = 8); appendix 14% (n = 14); colon 4% (n = 4);<br />rectum 19% (n = 19); pancreas 3% (n = 3); liver 2% (n = 2); gallbladder 1% (n = 1); primary tumor of unknown origin 1% (n = 1). Most<br />multifocal tumors were in the stomach (20%; n = 20), followed by the duodenum (1%; n = 1) and intestine (1%; n = 1). Metastases and<br />carcinoid syndrome were observed in 6% and 5% of the cases, respectively. General survival at the closure of the study was 80%.<br />Conclusions: Age and sex were similar to those described in the literature, while the colon and rectum represented 23% of all carcinoid<br />tumors. There was a predominance of gastroduodenal and rectal carcinoid tumors, probably because the series analyzed<br />was essentially endoscopic. In comparison with the literature, less cases of metastases or carcinoid syndrome were recorded and<br />survival was greater, perhaps due to earlier diagnosis and treatment.