Several of our findings may explain the mechanistic association between a high TMB and improved clinical outcomes, including higher proportions of tumor-infiltrating, CD8-positive, PD1-positive, T cells, increased PD-L1 tumor expression, upregulation of pathways involved in innate and adaptative immune response, including major histocompatibility complex class II antigen presentation, and a distinct mutational landscape. The gene discussed is CD274; the disease is neoplasm.