T-lymphocyte subsets in primary lung cancer

T-cell subsets in the peripheral blood of 63 primary lung cancer patients (23 with adenocarcinoma, 23 with squamous cell carcinoma and 17 with small cell carcinoma) and 24 normal healthy controls were determined by indirect immunofluorescence, using the monoclonal antibody reagents OKT3, OKT4 and OKT8. Correlations between T-lymphocyte subset values and stages or cell types of disease were sought. Total lymphocytes in the patient group were decreased. However, no significant difference from controls was seen in the percentage of OKT3-positive cells (Pan T-cells) in the cancer patients. The percentage of OKT8-positive cells (cytotoxic/suppressor) was increased in the early stage of disease whereas the percentage of OKT4 positive cells (inducer/helper) remained at the control level throughout all stages. The ratio of OKT4-positive to OKT8-positive T-cells (OKT4/OKT8), reflecting the balance of immunoregulatory T-cells, was, therefore, significantly decreased in patients with stage I-II lung cancer (P less than 0.05), especially in squamous cell lung cancer (P less than 0.05), whereas in stages III or IV, this T4/T8 ratio returned to the control level. In small cell carcinoma, the T4/T8 ratio was significantly decreased in stage III (P less than 0.01) and returned to the control level in stage IV.