ObjectiveTo evaluate the postoperative anal function of rectal cancer patients treated with transanal total mesorectal excision (taTME), and to analyze the influencing factors which resulted in low anterior resection syndrome (LARS) after taTME in this paper, so as to provide guidance for clinical practice.MethodsThe data about the patients with rectal cancer treated with taTME were collected at the Affiliated Nanchong Central Hospital of North Sichuan Medical College from December 2018 to December 2019, including the clinical data and follow-up data. Postoperative recovery condition of the patients’ anal function and the affecting factors caused the occurrence of severe LARS after taTME were analyzed. The patients’ anal function within 1, 6, and 12 months after taTME were evaluated, and the evaluation tools were LARS scale and Wexner scale. The follow-up period was up to December 30, 2020.ResultsA total of 67 patients were completed preoperative and postoperative follow-up at 1, 6, and 12 months. In terms of anal function, within 1 month after taTME was the worst period in which the anal function was the worst among all the points of time evaluated (1.49±0.33, 10.28±0.64, 6.42±0.60, and 3.73±0.61, respectively), and there was time trend during the follow-up period (F=66.101, P<0.001). In the first year after taTME, the patient’s anal function was in a state of continuous recovery, and the differences between the three points of time at 1, 6, and 12 months after taTME and preoperative anal function were statistically significant (P<0.010). The results of multivariate analysis indicated that the distance between the anastomotic stoma and the anal verge was independent risk factor affecting the postoperative anal function of the patients with taTME at 1 month and 6 months (P<0.010).ConclusionsWith time going, the postoperative anal function of the patients with taTME can be recovered to a certain extent. The distance between the anastomotic stoma and the anal verge was the independent factor affecting the postoperative function of the rectal cancer patients received taTME.