Multicenter analysis of impact of anastomotic leakage on long-term oncologic outcomes after curative resection of colon cancer

Background In rectal cancer, anastomotic leakage was reported to have a negative impact on both short- and long-term outcomes. However, there is limited data on the impact of anastomotic leakage on oncologic outcomes in patients with colon cancer. We aimed to evaluate the impact of anastomotic leakage on disease recurrence and long-term survival after curative resection of colon cancer. Methods This multicenter, retrospective cohort study of 4,919 consecutive patients utilized data from the Japanese Society for Cancer of the Colon and Rectum. Multivariable Cox regression analysis was used to adjust for confounding. Results The incidence of anastomotic leakage was 2.5% and 30-day mortality was 0.21%. The 5-year overall survival rate was 80.8% in the anastomotic leakage group, compared with 90.3% in the no leak group ( P = .001). In the multivariable analysis, anastomotic leakage was significantly associated with reduced overall survival rate (hazard ratio = 1.84; 95% confidence interval, 1.06–2.96). Overall disease recurrence rate was 14.1%: 21.2% in the anastomotic leakage group and 13.9% in the no leak group. There was a significant association between anastomotic leakage and local recurrence (hazard ratio = 4.63; 95% confidence interval, 1.60–10.6). In contrast, anastomotic leakage was not significantly associated with total distant recurrence. However, anastomotic leakage did show a tendency toward increasing peritoneal recurrence, although it did not reach statistical significance (hazard ratio = 2.59; 95% confidence interval, 0.79–6.29). Conclusion In our study population, anastomotic leakage was associated with reduced overall survival and with increased rate of local recurrence after curative resection for colon cancer.