Impact of anastomotic leakage on long-term survival of patients undergoing curative resection for colorectal cancer

Background: The impact of anastomotic leakage on immediate postoperative mortality in patients undergoing potentially curative resection for colorectal cancer is well recognized. Its impact on long-term survival is less clear. The aim of the present study was to evaluate the relationship between anastomotic leakage and long-term survival in patients undergoing potentially curative resection for colorectal cancer. Methods: A total of 2235 patients who underwent potentially curative resection for colorectal cancer between 1991 and 1994 in Scotland were included in the study. Five-year survival rates and adjusted hazard ratios were calculated. Results: Fourteen (16 per cent) of the 86 patients with an anastomotic leak died within 30 days of surgery compared with 83 (3.9 per cent) of 2149 without a leak. The 5-year cancer-specific survival rate, including postoperative deaths, was 42 per cent in patients with an anastomotic leak compared with 66.9 per cent in those with no leak (P < 0.001). Excluding postoperative deaths, respective values were 50 and 68.0 per cent (P < 0.001). The adjusted relative hazard ratios, for patients with an anastomotic leak compared with those without a leak, and excluding 30-day mortality, were 1.61 (95 percent confidence interval (c.i.) 1.19 to 2.16; P = 0.002) for overall survival and 1.99 (95 per cent c.i. 1.42 to 2.79; P < 0.001) for cancer-specific survival. Conclusion: Development of an anastomotic leak is associated with worse long-term survival after potentially curative resection for colorectal cancer.