Intersphincteric resection versus abdominoperineal resection for lower rectal cancer: A systematic review and meta-analysis.
BACKGROUND: The optimal surgical approach for lower rectal cancer (LRC) remains debated, particularly between intersphincteric resection (ISR) and abdominoperineal resection (APR). While ISR offers potential sphincter preservation, its oncological efficacy compared to APR is unclear. METHODS: A systematic review was conducted to compare clinical and oncological outcomes of ISR versus APR in LRC patients. On December 8, 2024, a comprehensive search of Medline, Embase, Cochrane Library, Scopus, and Web of Science identified 24 retrospective studies involving 4502 patients. Key outcomes analyzed included positive circumferential resection margin (CRM), number of harvested lymph nodes (LNs), local recurrence (LR), length of hospital stay (LOS), early postoperative complications, and survival. RESULTS: Twenty-four retrospective studies involving 4502 patients (ISR: 2266 (50.3%) and APR: 1558 (34.6%)) met the eligibility criteria. ISR was associated with significantly lower rates of positive CRM (risk ratio (RR): 0.41, p < 0.001), decreased early postoperative complications (RR: 0.76, p < 0.001), lower LR (RR: 0.63, p = 0.0038), and improvement in five-year overall survival (5YOS) (hazard ratio (HR) = 0.42, p < 0.001) and five-year disease-free survival (5YDFS) (HR = 0.59, p < 0.001). CONCLUSIONS: ISR demonstrates several advantages over APR in selected LRC patients, including lower rates of positive CRM, fewer early postoperative complications, reduced LR, greater LN harvest, shorter LOS, and improved long-term survival outcomes (5YOS and 5YDFS). Therefore, ISR can be considered a safe and effective alternative to APR in appropriately chosen patients, with careful patient selection and surgical expertise remaining essential.