[Clinical value of measurement of serum creatine kinase BB and neuron specific enolase for small cell lung cancer].

Serum creatine kinase BB (CK-BB) and neuron specific enolase (NSE) were measured with chromatography-fluorometric method and ABC-ELISA in 20 patients with small cell lung cancer (SCLC), 30 patients with non small cell lung cancer (NSCLC), 25 patients with benign pulmonary diseases (BPD) and 30 healthy subjects (C). The results revealed that serum concentrations of CK-BB and NSE in SCLC were significantly greater than those in other three groups (P < 0.001). The mean values of CK-BB and NSE in SCLC, NSCLC, BPD, C were 30.2, 8.4, 6.3, 4.3 IU/L and 52.2, 12.7, 10.3, 9.2 ng/ml, respectively. If values above 9.5 IU/L (CK-BB) and 20.8 ng/ml (NSE) were considered abnormal, 70% and 80% of the values of CK-BB and NSE in SCLC were positive, respectively, which were higher than those in NSCLC (P < 0.005). The serum levels of CK-BB had linear correlation with those of NSE in SCLC (r = 0.7934, P < 0.001). By combined determination, the sensitivity and specificity were increased to 90% and 94% respectively. Therefore, the results suggest that serum CK-BB and NSE be diagnostic markers for SCLC. Concurrent determination may raise their value in clinical use.