Abstract:Background and Aims Redo coloanal anastomosis after rectal resection can restore intestinal continuity in most patients with rectal anastomotic failure or local tumor recurrence, avoiding permanent enterostomy. However, this surgery is challenging and associated with a high incidence of surgical complications. The choice of surgical approach is crucial for reducing the difficulty of the procedure, ensuring surgical safety, and reducing postoperative complications. Therefore, this study summarized the experience of performing laparoscopic and transanal endoscopic-assisted dual-scope combination redo coloanal anastomosis over 8 years at a single center to provide an evidence-based reference for clinical practice.Methods The clinical data of 51 patients undergoing redo coloanal anastomosis in Division of Colorectal Surgery, the Sixth Affiliated Hospital of Sun Yat-sen University between October 2015 and August 2023 were retrospectively collected. Among them, 24 cases underwent transanal endoscopic-assisted dual-scope combination redo coloanal anastomosis (the dual-scope combination group), and 27 cases underwent laparoscopic r redo coloanal anastomosis (the laparoscopic group). Intraoperative and postoperative conditions of all patients were analyzed, and differences in relevant clinical variables between the dual-scope combination group and the laparoscopic group were compared.Results All 51 patients successfully underwent redo coloanal anastomosis. Methods of digestive tract reconstruction included Bacon operation in 30 cases, Dixon operation in 5 cases, Parks operation in 15 cases, and intersphincteric resection in 1 case. Among the 51 patients, 30 underwent pull-through resection with two-stage coloanal anastomosis, 5 underwent pull-through resection with single anastomosis, 3 underwent pull-through resection with double anastomosis, and 13 underwent one-stage manual anastomosis. Among them, 42 patients had an enterostomy before surgery, 6 underwent prophylactic enterostomy after surgery, and 3 did not undergo prophylactic enterostomy after surgery. The total operative time for the entire group was 296 (251-349) min, and the intraoperative blood loss was 100 (50-200) mL. There was no statistical difference in the operative time and intraoperative blood loss between the dual-scope combination and laparoscopic groups (both P>0.05). A total of 24 specimens were obtained transanally during the operation, with 5 in the laparoscopic group and 19 in the dual-scope combination group, showing a statistically significant difference (P<0.05). The postoperative hospital stay for the entire group was 17 (11-23.5) d. There was no statistical difference in the postoperative hospital stay between the dual-scope combination and laparoscopic groups ( both P>0.05). However, the time to postoperative gas passage and oral intake in the dual-scope combination group was shorter than in the laparoscopic group (both P<0.05). There were no patients in the entire group who were transferred to the ICU for treatment after surgery or died during hospitalization. Pathological examination of specimens from 9 patients with local tumor recurrence after surgery showed no tumor at the specimen margin. Sixteen patients in the entire group experienced complications (9 cases of Clavien-Dindo grade Ⅱ and 7 cases of grade Ⅲ or above), including 4 cases in the dual-scope combination group (16.67%) and 12 cases in the laparoscopic group (44.44%), with a statistically significant difference (χ2=4.554, P=0.033).Conclusion The choice of surgical approach and method for redo coloanal anastomosis should be based on the type of initial anastomotic failure, the distance of the lesion from the anus, the patient's overall condition, and the level of medical care in the hospital to develop individualized treatment plans. Compared with simple laparoscopic redo coloanal anastomosis, transanal endoscopic-assisted dual-scope combination redo coloanal anastomosis has the advantages of faster postoperative recovery and a lower incidence of postoperative complications. Moreover, further follow-up is needed to evaluate the differences in enterostomy reversal rate, long-term anal function, and quality of life after redo coloanal anastomosis by the two surgical methods.