Three tumor markers or CEA

CYFRA21-2 and NSE were assayed in 239 cases with lung cancer (adenocarcinoma 129

squamous-cell carcinoma 59

small cell lung cancer 35

mixed type of adenocarcinoma and squamous-cell carcinoma 16) and 66 cases with benign lung disease. The positive rate of CEA

CYFRA21-1 and NSE for detecting lung cancer were 51.4%

43.5% and 48.1% respectively. It seemed there was a relationship between the sensitivity and the pathologic patterns of lung cancer. The highest diagnostic sensitivities were 76.3% for CYFRA21-1 in the detection of squamous-cell carcinoma

57.4% for CEA in adenocarcinoma and 94.3% for NSE in the small cell lung cancer respectively. In 49 cases with pleural effusion (adenocarcinoma 27

small cell lung cancer 7

benign disease 15)

three tumor markers in serum and pleural fluid were both measued. The results indicated that the sensitivity of the CEA and CYFRA21-1 in pleural fluid in patients /with adenocarcinoma was superior to serum. The detection of the NSE in pleural fluid was a very reliable method in diagnosing the small cell lung cancer. The sensitivity and specificity of CEA

CYFRA21-1 and NSE in different pathologic patterns of lung cancer was compared and also the false positive and false negative in benign lung disease. Moreover

the clinical role and necessity of combined determination were also discussed.