Lenvatinib Exacerbates the Decrease in Skeletal Muscle Mass in Patients with Hepatocellular Carcinoma, Whereas Atezolizumab Plus Bevacizumab Does Not

Simple Summary: Sarcopenia, the loss of skeletal muscle mass and strength, is associated with poor clinical outcomes in patients with hepatocellular carcinoma (HCC). This study indicated that lenvatinib treatment significantly exacerbated the decrease in skeletal muscle mass, whereas atezolizumab plus bevacizumab (AB) treatment did not. Furthermore, skeletal muscle mass was found to be an independent predictor of survival, together with alpha-fetoprotein and albumin-bilirubin scores, using time-varying covariates in the Cox proportional hazards model. These findings suggest that maintaining a relatively high skeletal muscle mass during AB treatment is advantageous for improving the prognosis of HCC chemotherapy. This study aimed to evaluate chronological changes in skeletal muscle index (SMI), subcutaneous and visceral adipose tissue indices (SATI and VATI), AFP, PIVKA-II, and ALBI scores during atezolizumab plus bevacizumab (AB) or lenvatinib (LEN) treatment for hepatocellular carcinoma (HCC) and the effect of these changes on survival. A total of 94 patients with HCC (37 were on AB and 57 on LEN) were enrolled. SMI, SATI, VATI, AFP, PIVKA-II, and ALBI scores were analyzed at the time of the treatment introduction (Intro), 3 months after the introduction (3M), at drug discontinuation (End), and the last observational time (Last). The differences between chronological changes were analyzed using the Wilcoxon paired test. The independent predictors for survival and the changes in SMI during AB or LEN (c-SMI%) were analyzed using the Cox proportional hazards model treating all these factors as time-varying covariates and the analysis of covariance, respectively. SMI in the AB group was maintained over time (42.9-44.0-40.6-44.2 cm(2)/m(2)), whereas that in the LEN group significantly decreased during the Intro-3M (p < 0.05) and 3M-End (p < 0.05) period (46.5-45.1-42.8-42.1 cm(2)/m(2)). SMI (p < 0.001) was an independent predictor for survival together with AFP (p = 0.004) and ALBI score (p < 0.001). Drug choice (AB or LEN; p = 0.038) and PIVKA-II (p < 0.001) were extracted as independent predictors for c-SMI%. AB treatment was significantly superior to LEN in terms of maintaining skeletal muscle, which is an independent predictor for survival.