Lymphocyte subpopulations in peripheral blood and malignant effusions of cancer patients

The percentage of total T lymphocytes and helper and suppressor cells was determined in the peripheral blood and pleural and abdominal effusions of patients with advanced cancer. The ratio of helper to suppressor cells in the peripheral blood and in the effusions was calculated in each case. The percentage of total T lymphocytes and suppressor cells was found to be in a normal range. The percentage of helper cells in patients' peripheral blood and in ascites was slightly lower than normal. However, the percentage of helper cells in the pleural effusion was significantly higher than in the blood. The ratio of helper to suppressor cells in the pleural effusion was 1.46, compared to 0.82 in the blood (P less than 0.01). In patients with ascites the ratio in the blood was 1.05 and in the effusion 1.28. The ratio of helper to suppressor cells of all patients in the peripheral blood was 0.94, as compared to 1.36 in the effusion fluid (P less than 0.05). The imbalance in the T cell subsets found is most probably due to immunodepressions in the peripheral blood and immune reactivity in the effusions.