Multicentre analysis of oncological and survival outcomes following anastomotic leakage after rectal cancer surgery

Background: The association between diverting stomas and symptomatic anastomotic leakage after rectal cancer surgery was studied, as well as the impact of leakage on local recurrence, distant metastasis, and disease-free, overall and cancer-specific survival. Methods: Data from the Swedish Rectal Cancer Trial, Dutch TME trial, CAO/ARO/AIO-94 trial, EORTC 22921 trial and Polish Rectal Cancer Trial were pooled (n = 5187). All eligible patients without distant metastases at the time of low anterior resection were selected (n = 2726); overall survival was studied in patients aged 75 years or less (n = 2480). Multivariable models were used to study the association between diverting stomas and anastomotic leakage, and between leakage and recurrence or survival. Results: Some 9.7 per cent of patients were diagnosed with a symptomatic anastomotic leak; diverting stomas were negatively associated with leakage (11.6 per cent without and 7.8 per cent with a stoma; P = 0.002). Anastomotic leakage was negatively associated with overall survival in the multivariable analysis (hazard ratio (HR) 1.29 (95 per cent confidence interval 1.02 to 1.63); P = 0.034), but not with cancer-specific survival (HR 1.12 (0.83 to 1.52); P = 0.466). Conclusion: Diverting stomas were associated with less symptomatic anastomotic leakage. Oncological outcome was not significantly influenced by leakage, but overall survival was reduced.