The observed decline in CD19+ B cells, CD4+ T cells (18), and the CD4+/CD8+ ratio, coupled with an increase in CD8+ T cells in high-risk (IPI 3-5) and advanced-stage (III/IV) patients, points to a state of progressive immune suppression within the DLBCL tumor microenvironment. The gene discussed is CD8A; the disease is diffuse large B-cell lymphoma.