Influence of the ABO Blood Group System on Hepatocellular Carcinoma Recurrence After Liver Transplantation

The ABO blood group system may influence tumorigenesis, but its prognostic value in liver transplantation (LT) for hepatocellular carcinoma (HCC) has never been assessed.All consecutive patients who underwent LT for HCC between 2013 and 2017 at 9 centers were analyzed. Predictors of tumor recurrence were identified using multivariable analysis, while comparison between group A and non-A recipients was performed after propensity score matching.Among 925 LT recipients, 406 were blood group A, 94 group B, 380 group O, and 45 group AB. On multivariable analysis, group A was associated with tumor recurrence (hazard ratio [HR] = 1.574 [95% confidence interval; 95% CI = 1.034-2.394] P = 0.034). After propensity score matching, 1- and 5-y recurrence rates were 7.4% and 20.1% in group A recipients versus 3.3% and 13.2% in non-A recipients (HR = 1.66 [95% CI = 1.12-2.45], P = 0.011). One and 5-y recurrence-free survivals were 85.2% and 66.8% in group A recipients versus 88.5% and 71.3% in non-A recipients (HR = 1.38 [95% CI = 1.01-1.90], P = 0.045). Among recipients within Milan criteria (n = 604), 1- and 5-y recurrence rates were 5.8% and 12.7% in group A recipients versus 3.1% and 12.2% in non-A recipients (HR = 1.197 [95% CI = 0.721-1.987], P = 0.485). Among recipients outside Milan criteria (n = 182), 1- and 5-y recurrence rates were 12.1% and 43.8% in group A recipients versus 3.9% and 15.6% in non-A recipients (HR = 3.175 [95% CI = 1.526-6.608], P = 0.002).ABO blood system influences the oncological outcome of recipients undergoing LT for HCC. Its incorporation in the prognostication model of LT for HCC may allow improving the management of LT candidates.