Technique and results of novel intracorporeal “overlap” colorectal anastomosis for laparoscopic and robotic surgery

BACKGROUND: Laparoscopic colorectal procedures are widely adopted for colorectal cancer surgery. The double-stapling technique for circular colorectal anastomosis carries leakage rates of 11.2-13.4% and elevates stricture risk. In 2024, we introduced an innovative intracorporeal linear isoperistaltic "overlap" colorectal anastomosis; preliminary data from ten patients confirmed its safety and feasibility. This study aims to assess the feasibility and safety of the colorectal "overlap" anastomosis technique for laparoscopic and robotic surgery on a larger group of patients. METHODS: An observational study was conducted from 2023 to 2025. A total of 100 patients with adenocarcinoma of the distal sigmoid colon, rectosigmoid junction, or upper rectum underwent laparoscopic or robotic colorectal surgery with intracorporeal "overlap" colorectal anastomosis. Demographic, intraoperative, and postoperative data, including complications, length of hospital stay, and 30-day readmission rates, were analyzed. Colonoscopy at 6 months assessed anastomosis configuration and patency. RESULTS: (interquartile range [IQR]: 24.4-30.4); 76 patients were classified as American Society of Anesthesiologists (ASA) II and 24 were ASA III. Per pTNM staging, 33 patients had stage I, 27 stage II, 38 stage III, and 2 stage IV. Median blood loss was 30.0 mL (20-50), operative time 240.0 min (210.0-282.5), lymph nodes harvested 13 (11-18), and time to bowel function recovery 48 h (24-48). No intraoperative complications, conversions, or technical deviations, anastomotic leaks, major complications (Clavien-Dindo grades ≥ III), strictures, or 30-day readmissions occurred. Median postoperative stay was 5 days (4-6). CONCLUSIONS: The novel intracorporeal linear "overlap" colorectal anastomosis is safe and feasible and may be recommended as a reliable alternative to the conventional circular anastomosis in both laparoscopic and robotic colorectal surgery.