The best strategy for non-functioning, sporadic, G1-G2 pancreatic neuroendocrine tumors ≤2 cm is unknown. An active surveillance is usually recommended. The PROMID and the CLARINET studies proved the value of somatostatin analogue (SSA) treatment in advanced gastro-entero-pancreatic neuroendocrine tumors. Aim of this study is to assess the value of SSA in PanNET≤2 cm. We retrospectively collected data from 72 patients with sporadic non-functioning G1-G2 PanNETs≤2 cm, that were either treated with somatostatin analogues (n = 31) or underwent active surveillance (n = 41) at our Institution. At a median follow-up of 53.7 months, the median progression free survival was not reached in the treatment group versus an estimated PFS of 85 months in the control group (HR 0.11, p = 0.01), with a rate of progression or death up to 21.9% in the active surveillance group. Additionally, in the group of patients treated with somatostatin analogues the response rate was 16.1% with one complete response. Our monocentric experience demonstrated a significant antiproliferative activity of somatostatin analogues in patients with sporadic, non-functionating G1-G2 PanNETs ≤2 cm delaying tumor progression and distant spread in small lesions that sometimes may reveal unpredictable aggressiveness.
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