The role of somatostatin analogues in the adjuvant treatment of NETs of the stomach CT1–2N0M0, GRADE I–II, 1st clinical and morphological type: results of a single-center retrospective study

   Background: Gastric type 1 neuroendocrine neoplasms (gNENs) are relatively indolent malignancies with low metastatic potential. Endoscopic resection (ER) is considered the primary treatment, while somatostatin analogs (SSAs) have proven anti-secretory and anti-proliferative effects. However, routine adjuvant SSA therapy after ER is not universally recommended.

   Objective: To determine whether adjuvant therapy with SSAs in patients with type 1 gNENs affects the rate of repeated endoscopic resections due to metachronous lesions.

   Methods: We conducted a retrospective, single-center study which included patients with gNENs cT1–2N0M0, Grade I–II who underwent ER from 2007 to 2024. Two groups were compared: one received SSAs in the adjuvant setting, the other remained under observation only. Propensity score matching using a “cardinality matching” approach ensured balanced cohorts. The primary endpoint was the frequency of repeated ER. Statistical analyses were performed using Student’s t-test.

   Results: After matching, there was no statistically significant reduction in repeated ER among patients receiving SSAs (p > 0.05). Furthermore, no significant difference in the number of endoscopic examinations was observed between the groups.

   Conclusion: Routine adjuvant SSA therapy after ER does not appear to reduce the frequency of repeated resections in patients with type 1 gastric NENs, suggesting that such practice may be unnecessary.

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