Importance Preventing anastomotic leakage (AL) is crucial for colorectal surgery. Some studies have suggested a positive role of transanal drainage tubes (TDTs) in AL prevention after low anterior resection, but this finding is controversial.

Objective To assess the effect of TDTs in AL prevention after laparoscopic low anterior resection for rectal cancer.

Design, Setting, and Participants This multicenter randomized clinical trial with parallel groups (TDT vs non-TDT) was performed from February 26, 2016, to September 30, 2020. Participants included patients from 7 different hospitals in China who were undergoing laparoscopic low anterior resection with the double-stapling technique for mid-low rectal cancer; 576 patients were initially enrolled in this study, and 16 were later excluded. Ultimately, 560 patients were randomly divided between the TDT and non-TDT groups.

Interventions A silicone tube was inserted through the anus, and the tip of the tube was placed approximately 5 cm above the anastomosis under laparoscopy at the conclusion of surgery. The tube was fixed with a skin suture and connected to a drainage bag. The TDT was scheduled for removal 3 to 7 days after surgery.

Main Outcomes and Measures The primary end point was the postoperative AL rate within 30 days.

Results In total, 576 patients were initially enrolled in this study; 16 of these patients were excluded. Ultimately, 560 patients were randomly divided between the TDT group (n = 280; median age, 61.5 years [IQR, 54.0-68.8 years]; 177 men [63.2%]) and the non-TDT group (n = 280; median age, 62.0 years [IQR, 52.0-69.0 years]; 169 men [60.4%]). Intention-to-treat analysis showed no significant difference between the TDT and non-TDT groups in AL rates (18 [6.4%] vs 19 [6.8%]; relative risk, 0.947; 95% CI, 0.508-1.766; P = .87) or AL grades (grade B, 14 [5.0%] and grade C, 4 [1.4%] vs grade B, 11 [3.9%] and grade C, 8 [2.9%]; P = .43). In the stratified analysis based on diverting stomas, there was no significant difference in the AL rate between the groups, regardless of whether a diverting stoma was present (without stoma, 12 [5.8%] vs 15 [7.9%], P = .41; and with stoma, 6 [8.3%] vs 4 [4.5%], P = .50). Anal pain was the most common complaint from patients in the TDT group (130 of 280, 46.4%). Accidental early TDT removal occurred in 20 patients (7.1%), and no bleeding or iatrogenic colonic perforations were detected.

Conclusions and Relevance The results from this randomized clinical trial indicated that TDTs may not confer any benefit for AL prevention in patients who undergo laparoscopic low anterior resection for mid-low rectal cancer without preoperative radiotherapy.

Trial Registration ClinicalTrials.gov Identifier: NCT02686567