Predictive role of the monocyte-to-lymphocyte ratio in advanced hepatocellular carcinoma patients receiving anti-PD-1 therapy

The immune checkpoint inhibitor (ICIs) therapy has been proven effective in a range of solid tumors including hepatocellular carcinoma (HCC), non-small cell lung carcinoma and metastatic melanoma. However, only a subset of approximately 20% of patients shows an objective response to anti-PD-1 therapy in HCC. Furthermore, the response to anti-PD-1 therapy is not correlated with programmed cell death 1 ligand expression in tumor tissue. Therefore, it is urgent to identify a biomarker to predict the response of anti-PD-1 therapy.This retrospective study was conducted at the Fudan University Shanghai Cancer Center from December 2019 to June 2021. The monocyte-to-lymphocyte ratio (MLR) was analyzed using a receiver operating characteristic (ROC) curve. A Cox regression model and the log-rank test were used to analyze the relationship between the MLR value and the time to progression (TTP).A total of 34 advanced HCC patients were enrolled in this study. The cut-off point for the MLR at baseline was 0.35. Univariate and multivariate Cox regression models showed that the MLR at baseline was significantly correlated with the TTP (P<0.05). Consistent results were found for disease progression. The log-rank test showed that patients in the low MLR group had a longer TTP (P=0.0027). At the time of disease progression, the median TTP in the low and high MLR groups were 33 and 18 weeks, respectively (P=0.0047).The MLR can predict the response to anti-PD-1 therapy, and a high MLR is correlated with a short TTP in anti-PD-1-treated HCC patients.