Usefulness of the Lymphocyte-to-Monocyte Ratio in Predicting Prognosis in Patients with Hepatocellular Carcinoma Receiving Atezolizumab Plus Bevacizumab

Aim The lymphocyte-to-monocyte ratio (LMR) has emerged as a potential immune-related biomarker; however, its prognostic significance in patients with unresectable hepatocellular carcinoma (HCC) treated with atezolizumab plus bevacizumab (Atezo/Bev) remains unclear. To investigate the prognostic significance of the LMR in patients with unresectable HCC treated with Atezo/Bev. Methods This multicentre study included 941 patients with unresectable HCC treated with Atezo/Bev therapy at 30 institutions in Japan. The optimal LMR cutoff value was determined using time-dependent receiver operating characteristic (ROC) analysis. Multivariate survival analyses were performed for progression-free survival (PFS) and overall survival (OS). The prognostic utility of the LMR was compared with that of the neutrophil-to-lymphocyte ratio (NLR) using integrated discrimination improvement and net reclassification improvement. Results Time-dependent ROC analysis identified an optimal LMR cutoff value of 3.6 based on median OS. The median PFS was 5.6 months in patients with an LMR < 3.6 and 8.9 months in those with an LMR ≥ 3.6 (P<0.01). The disease control rate was significantly higher in the high LMR group (P<0.01). Multivariate analysis identified the LMR as an independent factor associated with prolonged PFS (hazard ratio [HR], 0.94; 95% confidence interval [CI], 0.90–0.98; P<0.01) and OS (HR, 0.90; 95% CI, 0.85–0.96; P<0.01). Compared with NLR, LMR demonstrated a significantly greater improvement in prognostic predictive performance for both PFS and OS (P<0.01). Conclusions The LMR is a simple and clinically useful prognostic biomarker for predicting both PFS and OS in patients with unresectable HCC treated with Atezo/Bev therapy.