In vitro monocyte maturation in squamous carcinoma of the lung.

Maturation of monocytes into macrophages in vitro has been assayed by a quantitative microtitre assay in patients with squamous-cell carcinoma of the lung. Monocyte maturation in autologous serum was significantly depressed in patients with both limited and extensive disease compared with normal controls, patients with chronic obstructive airways disease and controls matched for age, sex, smoking history, respiratory function and the presence of infection. Maturation of monocytes from patients with terminal non-malignant disease was depressed, though not to the same extent as in those with extensive malignancy. Monocytes from relatives of patients with squamous-cell carcinoma of the lung matured normally. In 10 patients with limited disease, in vitro monocyte maturation was repeated 6-12 weeks after operation, and was found to relate to prognosis.