Prognostic impact of liver metastases on immunotherapy in patients with advanced solid tumors: A secondary analysis of MSK-IMPACT retrospective cohort

The liver is one of the common metastatic sites of advanced solid tumors, and the prognosis of patients with liver metastases treated with immune checkpoint inhibitors (ICIs) is mostly poor. In this study, we further investigated the effect of liver metastasis on the prognosis of ICIs treatment for advanced solid tumors. Patients who received at least one ICIs treatment from 2011 to 2017 were selected from Memorial Sloan Kettering Cancer Center. Univariate and multivariate analyses were performed using Cox proportional hazards models. In addition, we examined the hazard ratios of subgroups using a stratified analysis method and assessed the model's sensitivity by propensity score. A total of 901 patients treated with ICIs were selected for secondary analysis in this study. Median overall survival was significantly shorter for liver metastases compared with patients without liver metastases (10.0 vs 25 months, P < .0001). Besides, liver metastasis was associated with higher mortality for those survivors ≥ 6 months (hazard ratio [HR]: 1.84; 95% confidence interval [CI]: 1.30-2.60), ≥ 1 year (HR: 1.83; 95% CI: 1.09-3.08), and ≥ 2 years (HR: 2.42; 95% CI: 1.01-5.78). In stratified analysis, male patients had a 123% increased risk of death (HR: 2.23, 95% CI: 1.65-3.00), which was significantly higher than that of female patients (HR: 1.30, 95% CI: 0.89-1.89; P for interaction < .048). After adjusting for potential confounders, the prognosis of patients with liver metastases remained an independent risk factor for ICIs (HR: 1.67, 95% CI: 1.31-2.12). Liver metastasis may be an independent risk factor for advanced solid tumors treated with ICIs.