USEFULNESS OF A MULTIPLE BIOMARKER ASSAY IN BRONCHOALVEOLAR LAVAGE (BAL) AND SERUM FOR THE DIAGNOSIS OF SMALL-CELL LUNG-CANCER

To evaluate the diagnostic usefulness of simultaneous determinations o f carcinoembryonic antigen (CEA), neuron specific enolase (NSE), chori onic gonadotrophin (HCG) and carbohydrate antigenic determinant 19-9 ( CA 19-9), we studied 48 patients with small cell lung carcinoma (SCLC) and 15 with nonmalignant lung disease. The combination of CEA-BAL, NS E-BAL, and NSE-serum taken together with results of bronchoscopy (hist ologic and cytologic) showed the highest discriminating power between malignant (SCLC) and nonmalignant lung disease. The sensitivity of bro nchoscopy alone was 35%. However, when bronchoscopy results were combi ned with 3 positive markers, the sensitivity increased to 71%, with at least 2 positive markers to 94%, and with at least 1 positive marker to 100%. When both bronchoscopy and all 3 markers were negative, the r esults showed a negative predictive value of 100%.