Early stoma closure after low anterior resection is not recommended due to postoperative complications and asymptomatic anastomotic leakage.

The safety of early stoma closure after lower anterior resection (LAR) for rectal cancer remains controversial. In this study, patients scheduled to undergo LAR and stoma creation for rectal cancer were recruited. In absence of anastomotic leakage on radiological examination, closure of the diverting ileostomy was performed within 2 weeks. The primary endpoint was incidence of the colorectal anastomosis leakage after early stoma closure. Because of the slow accrual rate, the study was closed before recruitment reached the planned number of patients (n = 20). Among the 13 patients enrolled between April 2019 and March 2021, early stoma closure was performed in seven patients (53.8%). Non-clinical anastomotic leakage, leakage identified only on radiological examination, occurred in five cases, resulting in rescheduling of stoma closure. One patient did not undergo early stoma closure due to ileus. After stoma closure, colorectal anastomotic leakage manifested in one case; its incidence rate was 14.2%. Surgical site infection occurred in 42.8% of patients. This study revealed that asymptomatic anastomotic leakage occurred frequently. Considering the low rate of successful cases and the high rate of complications, early stoma closure within 2 weeks after LAR should not be performed routinely. Trial registration: (UMIN000036382 registered on 03/04/2019).