Anastomotic leakage is associated with impaired overall and disease-free survival after curative rectal cancer resection: a propensity score analysis.

BACKGROUND: Whether anastomotic leakage (AL) has a negative impact on survival remains a matter of debate. This study aimed to assess the impact of AL on the overall and disease-free survival of patients undergoing curative resection of stages 1-3 rectal cancer using propensity-scoring methods.

METHODS: In a single-center study, 570 patients undergoing curative resection of stages 1-3 rectal cancer between January 2002 and December 2011 were assessed. The mean follow-up period was 4.7 ± 2.9 years. Patients who did and did not experience AL were compared using Cox regression and propensity score analyses.

RESULTS: Overall, 51 patients (8.9 %) experienced an AL. The characteristics of the patients were highly biased concerning AL (propensity score, 0.16 ± 0.12 vs. 0.09 ± 0.07; P < 0.001). Anastomotic leakage was uniformly associated with a significantly increased risk of mortality in unadjusted analysis [hazard ratio (HR) 2.30; 95 % confidence interval (CI) 1.40-3.76; P = 0.003], multivariable Cox regression (HR 2.27; 95 % CI 1.33-3.88; P = 0.005), and propensity score-adjusted Cox regression (HR 2.07; 95 % CI 1.21-3.55; P = 0.014). Similarly, disease-free survival was significantly impaired in patients who experienced AL according to unadjusted analysis (HR 1.88; 95 % CI 1.19-2.95; P = 0.011), multivariable Cox regression (HR 1.90; 95 % CI 1.17-3.09; P = 0.014), and propensity score-adjusted Cox regression (HR 2.31; 95 % CI 1.40-3.80; P = 0.002).

CONCLUSIONS: This is the first propensity score-based analysis providing evidence that oncologic outcome may be impaired after curative rectal cancer resection in patients with AL.