A solid-phase radioimmunoassay technique was used to quantitate antigenantibody reactions between various human cell lines and lung cancer patients' sera. Four human fetal lung cell lines a n d four human tumor cell lines were more or less reactive as antigens. Failure to obtain exact correspondence between reactions with these cell lines indicates that more than one antigen may b e required for detecting specific antibodies to the various lung tumor types.These results suggest that serum antibody detection might be a feasible approach to the immunodiagnosis of lung cancer a t stages when the tumor masses are relatively small. C U~C~T 38: 157-165, 1976.
ANCER RE5EARCH EMPHASIS HAS BEEN IN-C tensified in multiple areas of epidemiology, including probable risk factors and causative agents, but only recently has much attention been directed toward early immunologic diagnosis of cancer.5 We have been particularly interested in the possible serodiagnosis of human lung cancer because of the high frequency of lung tumors and the poor prognosis of patients once their tumors are I ecognized clinically.Quantitative assay of the carcinoembryonic antigen (CEA), described originally by Gold and Freeman,13 has been used as an adjunct to the diagnosis and treatment of lung cancer.25,32 However, it is now clear that elevated levels of serum CEA are present in sera of p~t i e n t s with many kinds of tumors (including lung tumors), in individuals with nonmalignant conditions, and in a small but significant proportion of apparently normal subjects.lg~ "5932 CEA quantitation is, therefore, somewhat limited in its usefulness as a diagnostic tool