Microcytotoxicity assays of tumor immunity in patients with bronchogenic carcinoma correlated with clinical status.

Peripheral blood lymphocytes from patients with bronchogenic carcinoma were tested in microcytotoxicity assays against cultured bronchogenic cancer cells, other types of tumor cells, and skin fibroblasts. Lymphocytes from patients who were postresection with no clinical evidence of residual or recurrent tumor were more frequently toxic against bronchogenic carcinoma than were lymphocytes from normal donors or from patients with clinically evident disease. Lymphocytes from patients with minimal or no tumor were more frequently toxic against bronchogenic cancer than against skin fibroblasts. Serum samples from a few patients rendered lymphocytes toxic for bronchogenic cancer cells, but this serum activity could not be correlated with the patient's clinical status.