Risk factors associated with adenocarcinoma development in gastric neuroendocrine tumors: A multicenter 10-year follow-up study.

There is a significant gap in the literature regarding the relationship between gastric neuroendocrine tumors (GNETs) and gastric adenocarcinoma. This study aimed to examine the incidence and risk factors of adenocarcinoma development in patients diagnosed with GNET. This study included patients who were diagnosed with GNET and were followed up for a maximum period of 120 months via annual endoscopy. The patients were divided into two groups according to whether they developed adenocarcinoma or not during their follow-up period. These two groups were compared in terms of histopathological and laboratory findings, and risk factors associated with adenocarcinoma were identified. The Kaplan-Meier method was used to estimate the cumulative probability of adenocarcinoma, considering the total number of risk factors. Out of the 107 patients included in the study, 25 (23.3%) developed adenocarcinoma during follow-up, with an incidence rate of 3.87 events per 100 person-years. The median follow-up period of patients in both groups was 72 months. Severe corpus atrophy, micronodular enterochromaffin-like cell hyperplasia, presence of anti-Helicobacter pylori antibodies, hemoglobin, vitamin B12, ferritin, and gastrin were found to be risk factors for adenocarcinoma. For adenocarcinoma, a cut-off value of four for the total number of risk factors yielded a sensitivity of 92.0% and a specificity of 92.7%. The risk of developing adenocarcinoma was approximately 15 times (hazard ratio: 15.6, 95% confidence interval: 3.6-66.5) higher in patients with at least three risk factors. By combining seven basic histopathological and laboratory findings, the development of adenocarcinoma in patients with GNET was successfully predicted.