Early Changes in Alpha-Fetoprotein Are a Useful Predictor of Efficacy of Atezolizumab plus Bevacizumab Treatment in Patients with Advanced Hepatocellular Carcinoma
<b><i>Introduction:</i></b> The aim of this study was to investigate the early changes in alpha-fetoprotein (AFP) and des-γ-carboxy prothrombin (DCP) levels in patients with advanced hepatocellular carcinoma (HCC) treated with atezolizumab plus bevacizumab and to evaluate the relationship between changes in these tumor markers and treatment efficacy. <b><i>Methods:</i></b> Of 58 consecutive patients who started atezolizumab plus bevacizumab at our institution, 50 patients with information on antitumor response obtained at 6 weeks after therapy were enrolled in this study and their treatment outcomes were retrospectively evaluated. <b><i>Results:</i></b> According to the Response Evaluation Criteria in Solid Tumors at 6 weeks, the objective response (OR) rate was 22.0% and the disease control (DC) rate was 78.0%. In patients who achieved OR at 6 weeks, median AFP and DCP ratios at weeks 1, 2, 3, and 6 were significantly lower than those in patients who did not achieve OR. AFP ratios in patients who did not achieve DC at 6 weeks (Non-6W-DC group) were significantly higher than in those who achieved DC at week 6 (6W-DC group). Median overall survival in the Non-6W-DC group was significantly shorter than in the 6W-DC group (156 days vs. not reached, <i>p</i> = 0.0008). An AFP ratio of 1.4 or higher at 3 weeks had a specificity of 88.0% and a sensitivity of 88.9% for predicting Non-6W-DC. Median progression-free survival was significantly shorter in patients with an AFP ratio of 1.4 or higher at 3 weeks than in those with an AFP ratio of <1.4 (42 days vs. 210 days, <i>p</i> = 0.0003). <b><i>Conclusion:</i></b> Early changes in AFP might be useful for predicting the antitumor efficacy of atezolizumab plus bevacizumab in patients with advanced HCC. An AFP ratio of 1.4 or higher at 3 weeks might be an early predictor of refractoriness to atezolizumab plus bevacizumab therapy.