Nevertheless, high TMB and microsatellite instability are FDA-approved biomarkers in other solid tumors for the treatment with PD-1 blocking therapy.21 22 Other factors that have been associated with response to immunotherapy in patients with melanoma are gene expression profiling,23–26 major histocompatibility complex (MHC) molecule expression,27 28 T cell receptor diversity,29 30 lymphocyte infiltration and other immune cell markers.31–38 A solution for better prediction may come from a combination of multiple biomarkers. This evidence concerns the gene PDCD1 and melanoma.