Enhanced neutrophil functions in a patient with colony-stimulating activity-producing lung cancer

We studied neutrophil functions in a patient with colony-stimulating activity (CSA)-producing lung cancer. A 59-year-old man had an abnormal chest X-ray and leucocytosis, predominantly with neutrophils. Pneumonectomy was performed, and the histological diagnosis of the tumour was large-cell carcinoma of the lung. The tumour induced marked granulocytosis in tumour-transplanted nude mice, and the conditioned media of the tumour contained very strong human-active CSA. Superoxide release and membrane depolarization in neutrophils stimulated by the chemotactic peptide, N-formyl-methionyl-leucyl-phenylalanine, were markedly enhanced in the patient. These findings suggest that CSA produced by the tumour primed neutrophil functions in vivo in the patient.