Immunocompetence of patients with bronchogenic carcinoma.

Patients with lung carcinoma were tested for number of circulating thymus-derived (T-)lymphocytes and lymphocyte cytotoxicity before treatment and following operation or radiation therapy or a combination of the two. The proportion of circulating T-lymphocytes in healthy individuals was 75%, and the T-lymphocyte level was 1, 460 per cubic millimeter. All patients with lung cancer had a significantly decreased percentage and absolute number of T-cells before any treatment. Patients tested six to eight weeks following pneumonectomy or lobectomy showed an increased proportion of circulating T-cells in comparison to pretreatment values. Functional activity of immune lymphocytes as shown by cytotoxicity assay also improved in comparison to pretreatment values. The potential value of tests for immunocompetence is discussed.