Is serum alpha-fetoprotein useful for predicting recurrence and mortality specific to hepatocellular carcinoma after hepatectomy? A test based on propensity scores and competing risks analysis

Background. Serum alpha-fetoprotein (AFP) is frequently used to predict posthepatectomy outcomes in patients with hepatocellular carcinoma (HCC), but its predictive value is still not established. Therefore, we assessed the prognostic significance of AFP status. Methods. Of 525 patients undergoing curative hepatectomy for HCC, 290 had preoperative AFP levels of ≥20 ng/mL (AFP-positive group) and 235 had AFP levels of <20 ng/mL (AFP-negative group). We compared the 2 groups with respect to time-to-recurrence, using the inverse probability of treatment weighted (IPTW) for the entire cohort and propensity score matching, and the cumulative incidence of HCC-specific mortality using competing risks regression. Results. During follow-up (median duration 64 months, range 2-137 months), HCC recurred in 54.9 % of the AFP-negative group and 52.4 % of the AFP-positive group; there was no death without recurrence. After IPTW adjustment, time-to-recurrence did not differ in the 2 groups (hazard ratio [HR] 0.86, 95 % confidence interval [95 % CI] 0.66-1.12; P = 0.28). In a propensity-score matched cohort (152 pairs), time-to-recurrence data were similar to those obtained by IPTW adjustment (HR 0.91, 95 % CI 0.65-1.25; P = 0.55). There was no difference in recurrence pattern (site and stage) or treatment between the 2 groups even after propensity-score matching. The adjusted HR evaluating the impact of AFP positivity on the risk of HCC-specific mortality was 0.77 (95 % CI 0.54-1.08; P = 0.13) A multivariable competing risks analysis also failed to reveal a significant correlation between baseline AFP level and HCC-specific mortality in the AFP-positive group. Conclusions. Preoperative AFP levels are not useful for predicting recurrence or survival endpoints following curative hepatectomy for HCC.