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The following is a summary of “Clinical significance of positive resection margin for patients with rectal neuroendocrine tumors within 20mm following initial endoscopic resection: A multi-center study,” published in the September 2024 issue of Surgery by Duan et al.

The incidence of rectal neuroendocrine tumors (RNETs) has risen significantly, with a substantial number of cases being suitable for endoscopic resection. However, the clinical implications of a positive resection margin following endoscopic removal of RNETs remain unclear, leading to ongoing debate about the necessity and effectiveness of salvage treatment in these patients. This large, multicenter, retrospective cohort study sought to clarify these issues by analyzing the medical records of patients who underwent endoscopic resection for RNETs. Patients were divided into two groups based on their resection margin status: those with positive margins and those with negative margins. 

The study compared overall survival (OS) and disease-free survival (DFS) between these groups and identified independent variables predicting positive resection margins using univariate and multivariate logistic regression analyses. Among 527 patients with RNET, 181 (34.3%) had positive resection margins following endoscopic resection. After a median follow-up period of 72 months, tumor recurrence was observed in 12 patients (2.2%), with those in the positive margin group showing significantly worse DFS. Key factors independently associated with a positive resection margin included the choice of endoscopic resection method, tumor location in the lower rectum, a neutrophil-to-lymphocyte ratio (NLR) greater than 4.44, and tumor size exceeding 14.89 mm. Based on these factors, a predictive model was developed, demonstrating high accuracy and strong clinical applicability, as confirmed by calibration curves and decision curve analysis (DCA). 

Importantly, the study found that implementing salvage treatment for patients with positive margins improved DFS, with salvage endoscopic resection offering similar survival benefits compared to salvage radical surgery. In conclusion, a positive resection margin following endoscopic resection of RNETs may indicate a poorer prognosis, but this can be mitigated through timely salvage treatment. Notably, salvage local resection was found to be as effective as radical surgery in enhancing survival outcomes, providing a less invasive yet equally beneficial alternative for managing patients with positive resection margins.

Source: sciencedirect.com/science/article/abs/pii/S0748798324007030