Endocrine Abstracts

Background: Gastric neuroendocrine tumours (g-NETs) constitute about 7% of digestive NETs, with type 1 g-NETs, linked to chronic atrophic gastritis, accounting for 80% of cases. These tumours are generally small, low-grade, and exhibit excellent long-term survival rates. Increased endoscopy and awareness have raised their incidence, prompting interest in management strategies. Current guidelines recommend either endoscopic surveillance or resection for type 1 g-NETs <10 mm, though these recommendations are largely based on expert opinion rather than strong scientific evidence. Most existing data come from Eastern populations, emphasizing the need for further research in Western populations. The study aims to evaluate the indolent behaviour of type 1 g-NETs <10 mm managed through endoscopic surveillance.

Methods: This study is a single-center, retrospective analysis of consecutive patients with type 1 g-NETs <10 mm, who were managed through endoscopic surveillance. The primary endpoint was progression-free survival. Statistical analysis was performed using MedCalc® software, with a p-value <0.05 considered statistically significant. A Cox proportional hazards regression model was applied to identify risk factors for disease progression.

Results: Of the 113 patients evaluated, 32 (28.3%) were excluded for not meeting the inclusion criteria, leaving a final cohort of 82 patients (72.6%) for analysis. The median patient age was 59 years, with 27 men (32.9%) and 55 women (67.1%). The median tumour size was 4 mm, with 92.7% classified as G1 tumours and 7.3% as G2, and a median Ki-67 index of 2%. Tumour progression (characterized by an increase in size >10 mm), was observed in 4 patients (4.9%) after a median of 75.5 months, necessitating further endoscopic treatment. No cases of metastatic progression were reported. Additionally, 3.6% of patients developed adenomas with low-grade dysplasia, and 1.2% developed early gastric cancer. Three patients (3.6%) died during follow-up, though none of the deaths were tumour-related. The median progression-free survival and overall survival were both 59 months [range 2-287]. No statistically significant prognostic factors for tumour progression were identified in the univariate analysis.

Conclusions: Type 1 g-NETs <10 mm are typically indolent and don’t require invasive treatment at the time of diagnosis.