[T antigen test of sputum--a new simple method for the screening of lung cancer]

The sputum specimens from 116 healthy persons and 216 cases of benign and malignant lung diseases were detected for T antigen using a strip test by enzyme galactose oxidase-Schiff sequence. The result shows that 165 cases of the 182 patients with lung cancer, confirmed by cytology and histology, had positive results, whereas 22/116 (19.0%) of healthy controls were positive. So the sensitivity was 90.7% and the specificity was 81.0%. In 28 cases of patients whose cytology of sputa showed various degrees of dysplasia, 21 were found T antigen positive, of which 15 patients were identified to be lung cancer in the follow-up study. In addition, three cases of early lung cancer in this study were also positive, suggesting that T antigen was expressed at an earlier stage in the malignant process. The study has indicated that T antigen test of sputum is a sensitive method for the diagnosis of lung cancer. It may also be a promising approach for the massive screening of lung cancer in terms of its rapidity, economy and simplicity.