Protective ileostomy increased the incidence of rectal stenosis after anterior resection for rectal cancer

BACKGROUND: In most of the views, rectal stenosis after anterior resection for rectal cancer results from pelvic radiotherapy. However, patients without receiving radiotherapy also suffer stenosis. In this study, we evaluated the factors associated with rectal stenosis after anterior rectal resection (ARR). METHODS: We conducted a retrospective study with ARR patients who underwent neoadjuvant chemoradiotherapy and the patients without radiotherapy. Patients who received watch and wait strategy with a clinical complete response after chemoradiotherapy were also included. Patients with colonoscopy follow-up were included for further analyses; 439 patients who underwent neoadjuvant chemoradiotherapy; 545 patients who received ARR without radiotherapy and 33 patients who received watch and wait strategy. Stenosis was diagnosed when a 12-mm diameter colonoscopy could not be passed through the rectum. Univariate and multivariate logistic regression analyses were performed to identify variables associated with rectal stenosis. RESULTS: According to the multivariate analysis in patients receiving ARR, both protective stoma and preoperative radiotherapy affected the occurrence of stenosis, with the odds ratios (ORs) of 3.375 and 2.251, respectively. According to the multivariate analysis, a preventive ileostomy was the only factor associated with stenosis both in patients receiving preoperative radiotherapy and without radiotherapy. Non-reversal ileostomy and long time between ileostomy and restoration increased the possibility of stenosis. In 33 patients who received watch and wait strategy, only one patient (3%) experienced stenosis. CONCLUSION: Both surgery and radiotherapy are risk factors for rectal stenosis in rectal cancer patients. Compared to preoperative radiotherapy, a protective ileostomy is a more critical factor associated with rectal stenosis. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13014-022-02031-4.