The type, density, and location of immune cells within the tumor microenvironment (TME) were reported to affect the efficacy of anti-PD-1/PD-L1-based immunotherapy, which led to a concept called “hot” (highly infiltrated) and “cold” (poorly infiltrated) immune tumors, an unofficial classification of tumors that has been increasingly advocated (12). The gene discussed is CD274; the disease is neoplasm.