Short Distal Resection Margin Does Not Increase Recurrence Risk After R0 Resection for Rectal Neuroendocrine Tumors: A Single‐Institution Retrospective Study of 208 Patients

Aim The optimal distal resection margin (DRM) for rectal neuroendocrine tumors (NETs) remains unclear. Although rectal NETs are generally considered indolent, aggressive resection may compromise anorectal function. This study aimed to investigate whether shorter DRM affects recurrence risk in patients with rectal NETs undergoing curative resection. Methods This retrospective study included 208 patients with rectal NETs who underwent total mesorectal excision (TME) at a single institution between January 2005 and December 2023. The patients were categorized into two groups based on DRM length: shorter DRM (SDRM) (≤ 10 mm) and longer DRM (LDRM) (> 10 mm). Clinicopathological characteristics, recurrence patterns, and survival outcomes were compared between the groups. A fine‐grey regression model was used to identify independent predictors of recurrence. Results Among the 208 patients, 91 (43.8%) had a short DRM. There was no significant difference in the overall recurrence rate between the SDRM and LDRM groups (6.6% vs. 6.0%, p = 1.000), and no local recurrence was reported in either group. In multivariate analysis, tumor size > 20 mm (hazard ratio [HR], 7.01; p = 0.008) and NET G2 (HR, 5.18; p = 0.03) were independent risk factors for recurrence, whereas a short DRM was not. Five‐year overall recurrence and survival rates did not differ between the groups. Conclusions In rectal NETs, SDRM may not increase the risk of recurrence when R0 resection is achieved. While oncological radicality should remain the highest priority, minimizing DRM may be oncologically safe and could support more function‐preserving surgery, particularly for rectal NET G1/G2.