The Low Platelet Count at the Start of Atezolizumab Plus Bevacizumab Therapy for Unresectable Hepatocellular Carcinoma Predicts Deteriorated Liver Function at the Time of Disease Progression Thereafter: A Multicenter Analysis.

[BACKGROUND] There are few reports on the factors that contribute to liver function at the time of disease progression after first-line systemic therapy for unresectable hepatocellular carcinoma (u-HCC). Therefore, our multicenter study investigated these factors in u-HCC patients treated with atezolizumab plus bevacizumab (ATZ/BEV).

[METHODS] We enrolled 101 patients with u-HCC who had preserved liver function, Child-Pugh (CP) Class A at baseline, and were treated with ATZ/BEV as the first-line systemic chemotherapy. All were evaluated for progressive disease (PD) during the observational period, and those who had Child-Pugh Class A at evaluation of PD were classified as Group A, with those who had Child-Pugh Class B at evaluation of PD being classified as Group B.

[RESULTS] Comparing the two groups, Group A had significantly higher platelet counts than Group B (p = 0.008). Receiver operating characteristic curve analysis for differentiating CP Class A versus B at the time of evaluation of PD, using platelet counts, showed that the area under the curve was 0.690 and the optimal cutoff value was 12.8 × 10/μL. Multivariate analysis showed that only the low platelet count was associated with CP Class B at the time of evaluation of PD (< 12.8/≥ 12.8 × 10/μL: OR 3.780, p = 0.022).

[CONCLUSIONS] The data suggest that the platelet count can be used to predict liver function at the time of evaluation of PD after ATZ/BEV therapy in patients with u-HCC. Treatment strategies in u-HCC patients with low platelet counts should be conducted by taking into account deterioration of liver function after ATZ/BEV therapy.