Carcinoembryonic antigen fraction in lung cancer.

Serum levels of a carcinoembryonic antigen fraction were measured in 195 patients with lung diseases by means of a radioimmunoassay technique. Overall sensitivity for lung cancer was 54.6% and specificity was 71.4%, but the carcinoembryonic antigen fraction was more frequently raised among patients with lung adenocarcinoma than in those bearing epidermoid or undifferentiated carcinomas. It is concluded that this radioimmunoassay technique is an useful adjunct in the diagnosis of lung adenocarcinoma and shows a good correlation with its clinical stage.