QUANTITATIVE-ANALYSIS OF CARCINOEMBRYONIC ANTIGEN, SQUAMOUS-CELL CARCINOMA ANTIGEN, CA-125, AND CA-50 CYTOSOLIC CONTENT IN NONSMALL CELL LUNG-CANCER

Background. The cytosolic content of carcinoembryonic antigen (CEA), s quamous cell carcinoma (SCC), CA 125, and CA 50 antigens in non-small cell lung cancer (NSCLC) is analyzed in this study. The aim was to asc ertain the relationship between tumor marker content and the clinicopa thologic aspects of this neoplasm. Methods. Lung tissue samples were o btained at the time of surgery from 75 patients with NSCLC patients (s amples of tumor and unaffected tissue) and 29 subjects with idiopathic pneumothorax. All determinations were performed on cytosols obtained from lung specimens. CEA and CA 125 were determined by enzyme immunoas say, SCC antigen by radioimmunoassay, and CA 50 by fluoroimmunoassay. Tumor marker content was analyzed by TNM stage, histologic type, tumor grade, and number of atypias. Results. The concentration of the four markers was significantly higher in cytosol obtained from neoplastic t issue. Frequency of elevated levels of CEA was higher in adenocarcinom a (87% cases expressing high levels of the marker), SCC antigen in epi dermoid carcinoma (65% expressing high levels), and CA 125 in large ce ll carcinomas (100% expressing high levels). No association was found between TNM stage and cytosol concentration for any of the four marker s. CEA exhibited significantly greater concentration in well different iated tumors, whereas this was true of CA 125 in poorly differentiated tumors. CA 125 content was higher in tumors with more atypia. Conclus ions. Cytosolic quantification of tumor markers may be an adjuvant mec hanism to evaluate histologic subtypes of non-small cell lung cancer a nd identification of tumors with poorly differentiated features.