(11) have demonstrated that low tumor purity is associated not only with poor prognosis but also with immunotherapy-associated markers, such as PD-1 (Programmed cell death protein 1), PD-L1 (Programmed cell death ligand-protein 1), CTLA-4 (cytotoxic T-lymphocyte-associated protein 4), LAG-3 (Lymphocyte-activation gene 3), and TIM-3 (T cell immunoglobulin- and mucin-domain-containing molecule-3). The gene discussed is CTLA4; the disease is neoplasm.