Predictive factors associated with anastomotic leakage after resection of rectal cancer: a multicenter study with the Hiroshima Surgical study group of Clinical Oncology.

PURPOSE: Several factors have been reported as risk factors for anastomotic leakage after resection of rectal cancer. This study aimed to evaluate the risk factors for anastomotic leakage, including nutritional and immunological indices, following rectal cancer resection. METHODS: This study used a multicenter database of 803 patients from the Hiroshima Surgical study group of Clinical Oncology who underwent rectal resection with stapled anastomosis for rectal cancer between October 2016 and April 2020. RESULTS: In total, 64 patients (8.0%) developed postoperative anastomotic leakage. Five factors were significantly associated with the development of anastomotic leakage after rectal cancer resection with stapled anastomosis: male sex, diabetes mellitus, C-reactive protein/albumin ratio ≥ 0.07, prognostic nutritional index < 40, and low anastomosis under peritoneal reflection. The incidence of anastomotic leakage was correlated with the number of risk factors. The novel predictive formula based on odds ratios in the multivariate analysis was useful for identifying patients at high risk for anastomotic leakage. Diverting ileostomy reduced the ratio of anastomotic leakage ≥ grade III after rectal cancer resection. CONCLUSIONS: Male sex, diabetes mellitus, C-reactive protein/albumin ratio ≥ 0.07, prognostic nutritional index < 40, and low anastomosis under peritoneal reflection are possible risk factors for developing anastomotic leakage after rectal cancer resection with the stapled anastomosis. Patients at high risk of anastomotic leakage should be assessed for the potential benefits of diverting stoma.