CD8A and neoplasm: However, the CD4+/CD8+ ratio in TILs is inverted in tumor tissues compared to peripheral blood, CD4+ cells are significantly reduced (p < 0.0013), while CD8+ cell numbers remain comparable to those in peripheral blood (p = 0.92), resulting in a significantly decreased CD4+/CD8+ ratio in tumor tissues, which was particularly pronounced in advanced stages of the disease (58).