Intraoperative Rectal Lavage to Prevent Local Recurrence After Laparoscopic Mid-to-Low Rectal Cancer Resection: A Multicenter Randomized Trial

Inclusion Criteria: * Age between 18 and 75 years old. * Pathologically confirmed rectal adenocarcinoma. * Mid-to-low rectal cancer with the tumor lower margin located ≤10 cm from the anal verge. * Underwent laparoscopic radical resection for rectal cancer with sphincter preservation. * Without concomitant multiple primary malignancies. * Adequate organ function. * Patients or their family members were able to understand the study protocol, willing to participate in this study, and provided written informed consent. Exclusion Criteria: * Concomitant other malignancies or a history of prior malignancies. * Abdominal perineal resection (Miles' operation) or Hartmann's procedure. * Failure to open the peritoneal reflection during surgery. * History of previous pelvic floor surgery. * Emergency surgery due to bowel obstruction. * Severe hepatic, renal, cardiopulmonary, or coagulation dysfunction, or other severe comorbidities that render the patient unable to tolerate the procedure. * History of severe psychiatric disorders. * Pregnant or lactating women. * Any other clinical or laboratory conditions considered unsuitable for participation in the trial by the investigators.