We hypothesize that patients with a reversed CD4/CD8 ratio in our cohort lack a balanced distribution of T cell subsets with a needed predominance of T helper cells (CD3+ CD4 +), which upon successful activation by ICI can, via necessary CD4+ mediation, manage a higher recruitment of CD8+ cells (achieving ultimately a prognostically favorable decrease in the CD4/8 ratio), that convey the direct cytotoxic response against cancer. The gene discussed is CD8A; the disease is cancer.