BackgroundThe impact of sarcopenia on the prognosis of patients with hepatocellular carcinoma (HCC) who receive transcatheter intra-arterial therapies, including transcatheter arterial chemoembolization and transcatheter arterial infusion chemotherapy, remains unclear. We investigated the prognostic value of skeletal muscle loss (SML) stratified by cutoffs for sarcopenia and rate of change in skeletal muscle mass over 6 months.MethodsWe retrospectively evaluated 102 patients with HCC treated with transcatheter intra-arterial therapies between 2005 and 2015. Computed tomography images of the third lumbar vertebra (L3) were analyzed to obtain the skeletal muscle area normalized for the height squared, defined as the skeletal muscle index at L3 (L3 SMI), before and 6 months after treatment. Low or high SMI was defined using cutoff values of 42 cm2/m2 in men and 38 cm2/m2 in women. The rate of change in skeletal muscle mass (ΔL3 SMI) over 6 months was calculated. Overall survival (OS) was compared in groups classified by baseline L3 SMI and ΔL3 SMI; prognostic significance was assessed with univariate and multivariate analyses, using Cox proportional hazards models.ResultsOS did not differ significantly between groups with low (n = 31) and high (n = 71) SMI at baseline (P = 0.172), but OS was significantly poorer in patients with SML (n = 41), defined as ΔL3 SMI < − 4.6% over 6 months than in those without SML (n = 61, P = 0.018). On multivariate analysis, SML (hazard ratio [HR], 1.675; 95% confidence interval [CI], 1.031–2.721; P = 0.037), serum alpha-fetoprotein ≥20 ng/mL (HR, 2.550; 95% CI, 1.440–4.515; P = 0.001), and maximum tumor diameter ≥ 30 mm (HR, 1.925; 95% CI, 1.166–3.179; P = 0.010) were independent predictors of poor OS. Baseline L3 SMI was not significantly associated with OS (HR, 1.405; 95% CI, 0.861–2.293; P = 0.174).ConclusionsΔL3 SMI was an independent prognostic factor in patients with HCC treated with transcatheter intra-arterial therapies. Further study is required to reveal whether prevention of skeletal muscle depletion might be a new therapeutic strategy to contribute to improved clinical outcomes in patients with HCC.