Anastomotic leakage is associated with poor long-term outcome in patients after curative colorectal resection for malignancy

The impact of anastomotic leakage on long-term outcomes after curative surgery for colorectal cancer has not been well documented. This study aimed to investigate the effect of anastomotic leakage on survival and tumor recurrence in patients who underwent curative resection for colorectal cancer. Prospectively collected data of the 1,580 patients ( 904 men) of a median age of 70 years ( range: 24 - 94), who underwent potentially curative resection for colorectal cancer between 1996 and 2004, were reviewed. Cancer-specific survival and disease recurrence were analyzed using Kaplan Meier method, and variables were compared with log rank test. Cox regression model was used in multivariate analysis. The cancer was situated in the colon and the rectum in 933 and 647 patients, respectively. Anastomotic leakage occurred in 60 patients ( clinical leakage: n= 48; radiological leak: n= 12). The leakage rate was significantly higher in patients with surgery for rectal cancer (6.3 vs 2.0%, p< 0.001). The 5-year cancer-specific survivals were 56.9% in those with leakage and 75.9% in those without leakage (p= 0.012). The 5-year systemic recurrence rates were 48.4 and 22.6% in patients with and without anastomotic leak, respectively ( p= 0.001), whereas the 5-year local recurrence rates were 12.9 and 5.7%, respectively ( p= 0.009). Anastomotic leakage remained an independent factor associated with a worse cancer-specific survival ( p= 0.043, hazard ratio: 1.63, 95% CI: 1.02 - 2.60) and a higher systemic recurrence rate ( hazard ratio: 1.94, 95% CI: 1.23 - 3.06, p= 0.004) on multivariate analysis. In rectal cancer, anastomotic leakage was an independent factor for a higher local recurrence rate ( hazard ratio: 2.55, 95% CI: 1.07 - 6.06, p= 0.034). In conclusion, anastomotic leakage is associated with a poor survival and a higher tumor recurrence rate after curative resection of colorectal cancer. Efforts should be undertaken to avoid this complication to improve the long-term outcome.