No Muscle Depletion with High Visceral Fat as a Novel Beneficial Biomarker of Sorafenib for Hepatocellular Carcinoma

Background: Sorafenib is a standard therapy for patients with advanced hepatocellular carcinoma (HCC). However, no predictive biomarkers of sorafenib efficacy have been discovered. Herein, we investigated the impact of body composition, such as skeletal muscle and visceral fat, on the prognosis of advanced HCC patients treated with sorafenib. Methods: We enrolled 100 patients with advanced HCC treated with sorafenib. Prior to receiving sorafenib therapy, skeletal muscle index (SMI) and visceral fat area (VFA) were measured using computed tomography at the third lumbar vertebra and umbilical level, respectively. Muscle depletion was defined as an SMI value < 42 cm(2)/m(2) in men and < 38 cm(2)/m(2) in women. High VFA (H-VFA) was defined as a value 100 cm(2). In addition to SMI and VFA, we also analyzed various clinical parameters as potential prognostic factors. Results: Multivariate analysis showed that having a tumor number < 7 (hazard ratio [HR] = 0.409, p < 0.001), absence of extrahepatic spread (EHS) (HR = 0.562, p < 0.001), absence of muscle depletion (HR = 0.498, p = 0.006), and H-VFA (HR = 0.556, p = 0.031) were significant factors for long-term survival. Therefore, we evaluated the prognosis of those with no muscle depletion with H-VFA. The no muscle depletion with H-VFA group showed significantly longer survival than the other group (median survival time 15.6 vs. 11.0 months, p = 0.003). Multivariate analysis showed that having a tumor number < 7 (HR = 0.454, p = 0.001), absence of EHS (HR = 0.511, p = 0.008), and no muscle depletion with H-VFA (HR = 0.454, p = 0.002) were significant predictors of survival. Conclusions: We identified no muscle depletion with H-VFA as a novel biomarker for advanced HCC patients treated with sorafenib.