EVALUATION OF SERUM NEURAL CELL-ADHESION MOLECULE AS A NEW TUMOR-MARKER IN SMALL-CELL LUNG-CANCER

Background. Small cell lung cancer (SCLC) is distinguished from other histologic types of lung cancer by possessing a variety of neuroendocr ine properties. Neuron-specific enolase (NSE) is the most frequently e levated tumor marker for patients with SCLC at diagnosis. To assess th e value of neural cell adhesion molecules (NCAM), another possible tum or marker for small cell lung cancer, NCAM was evaluated in the sera o f patients with histologically confirmed SCLC in two prospective multi center trials. Methods. The study includes 221 patients with SCLC, nor mal human blood donors (n = 34), patients with benign lung disease (n = 53), and patients with non-small cell lung cancer (n = 28). NCAM was determined by means of an enzyme immunoassay, NSE by a radioimmunoass ay. Results. The data show the following: (1) 51% (113 of 221) of all patients with SCLC had NCAM levels higher than 20 U/ml, 34% (75 of 221 ) had NSE levels higher than 25 ng/ml; (2) levels of both markers sign ificantly differ between limited and extensive disease patients; (3) p atients with pathologic NCAM and NSE levels have significantly shorter survival times; (4) a positive correlation between pretreatment NSE a nd NCAM levels was found (n 221, r = 0.60); and (5) a correlation betw een serum marker levels and clinical status was found in follow-up stu dies of 19 patients. Conclusions. From these data, it is concluded tha t NCAM is, along with NSE, a potential tumor marker for SCLC.