Sarcopenia as a predictor of post-transplant tumor recurrence after living donor liver transplantation for hepatocellular carcinoma beyond the Milan criteria

To evaluate the association between sarcopenia and tumor recurrence after living donor liver transplantation (LDLT) in patients with advanced hepatocellular carcinoma (HCC), we analyzed 92 males who underwent LDLT for treating HCC beyond the Milan criteria. Sarcopenia was defined when the height-normalized psoas muscle thickness was < 15.5 mm/m at the L3 vertebra level on computed tomography based on an optimum stratification method using the Gray's test statistic. Survival analysis was performed with death as a competing risk event. The primary outcome was post-transplant HCC recurrence. The median follow-up time was 36 months. There was a 9% increase in recurrence risk per unit decrease in height-normalized psoas muscle thickness. Twenty-six (36.1%) of 72 sarcopenic recipients developed HCC recurrence, whereas only one (5.0%) of 20 non-sarcopenic recipients developed HCC recurrence. Recurrence risk was greater in sarcopenic patients in univariable analysis (hazard ratio [HR] = 8.06 [1.06-16.70], p = 0.044) and in multivariable analysis (HR = 9.49 [1.18-76.32], p = 0.034). Greater alpha-fetoprotein and microvascular invasion were also identified as independent risk factors. Incorporation of sarcopenia improved the model fitness and prediction power of the estimation model. In conclusion, sarcopenia appears to be one of the important host factors modulating tumor recurrence risk after LDLT for advanced HCC.