Prophylactic ileostomy versus nonprophylactic ileostomy in laparoscopic low anterior resection for rectal cancer (PILLAR): a prospective, multicenter, cohort study in China

INTRODUCTION: The role of prophylactic ileostomy and its potential to reduce the risk of postoperative complications such as anastomotic leakage remains unclear. METHODS: The PILLAR study (2018-2020, China, 17 centers) prospectively compared prophylactic ileostomy (PI) versus nonprophylactic ileostomy (NPI) in patients undergoing laparoscopic low anterior resection for rectal cancer. The primary endpoint was the anastomotic leakage rate. Secondary endpoints included postoperative complications, leakage management/outcomes, and leakage-associated risk factors. RESULTS: A prospective study was conducted to gather data from 728 patients who underwent laparoscopic low anterior resection for rectal cancer, 192 (26.4%) of whom underwent PI. Seven cases of anastomotic leakage were observed in the PI group (3.6%) and 25 cases were observed in the NPI group (4.7%). Statistical analysis revealed no significant difference in the incidence of anastomotic leakage between the two groups. Moreover, the total complication rates were 17.2% in the PI group and 10.3% in the NPI group (P = 0.012). However, the patients with anastomotic leakage in the NPI group had more severe abdominal infections, as evidenced by the C-reactive protein (CRP) values on postoperative day 5 (184.1 ± 72.2 mg/L and 77.2 ± 17.0 mg/L in the NPI and PI groups, respectively) (P<0.001). Patients' postoperative procalcitonin (PCT) values similarly support this conclusion. Notably, despite this difference in infection severity, there was no statistically significant difference in the treatment or outcomes of patients with anastomotic leakage in either group. Furthermore, male sex and CRP levels on the fifth postoperative day are identified as independent risk factors for anastomotic leakage. CONCLUSIONS: PI may have failed to decrease the incidence of anastomotic leakage in patients who underwent laparoscopic low-anterior resection for rectal cancer. Given the higher complication rate associated with PI, its use as a preventive measure for patients at risk of anastomotic leakage should be carefully considered.