We found that a high CD4+ T-lymphocyte content in peripheral blood and a high CD4+/CD8+ ratio were associated with better tumor differentiation, an earlier clinical pathological stage, lower Ki67 expression, shallower tumor infiltration, a smaller number of lymph node metastases, a lower CEA content, and a lower likelihood of nerve or vascular infiltration (P < 0.05). The gene discussed is CD8A; the disease is neoplasm.