To analyze the indications and outcomes of sequential super minimally invasive stepwise endoscopic full-thickness resection after neoadjuvant therapy for locally advanced rectal cancer (LARC).

Clinical data of LARC patients after neoadjuvant therapy who were treated with sft-SMIR at the First Medical Center of PLA General Hospital from June 2024 to June 2025 were retrospectively analyzed. Indicators of indication selection (rectal auscultation, rectal-enhanced MRI, endoscopic performance and carcinoembryonic antigen level), perioperative complications, pathological results, healing status of wounds, anal function and quality of life were mainly analyzed.

A total of 8 patients with stage cT_2-4N_0-2M₀ LARC were included, all of whom were treated with neoadjuvant therapy with or without immunotherapy.After neoadjuvant therapy to achieve near clinical complete remission in 5 and clinical complete remission in 3, super minimally invasive stepwise endoscopic full-thickness resection was performed in 8.The sft-SMIR bloc resection rate and R0 resection rate were 100%.Postoperative pathologic results showed inflammatory or residual moderate heterogeneous hyperplasia in 5 cases, residual carcinoma invading the mucosal layer in 2 cases (ypTis stage), and residual carcinoma invading the muscular layer in 1 case (ypT2 stage). The mean duration of surgery was at 71 minutes, with a mean pain score(VAS)of 1.75 and a mean rectal function assessment LARS score of 20 (0-41). No adverse events such as delayed perforation or gastrointestinal fistula were observed during the follow-up period of 1-12 months (median interval 4 months).

Super minimally invasive stepwise endoscopic full-thickness resection is safe and effective for rectal cancer that reaches clinical complete remission or near clinical complete remission after neoadjuvant therapy.