ABSTRACT
We treated 472 patients with lung cancer from 1983 though 1993. Of the total number of the cases, early lung cancer accounted for 31 caces (6.6%), 6 of the hilar and 25 of the peripheral type. Of the 6 hilar type early lung cancer cases, 3 cases were detected by mass screening (2 cases were detected by sputum cytology). On the other hand, of the 25 cases of the peripheral type early lung cancer, 10 cases were detected by mass screening. All the 10 peripheral type early lung cancer cases detected by mass screening were detected by chest roentogenography. The 5-year survival rates for the hilar and peripheral type early lung cancer were 100% and 94.4%, respectively. For the improvement of prognosis of lung cancer, every effort should be made to detect lung cancer at an early stage. Careful lung cancer screening such as sputum cytology and bronchoscopy in a highrisk group and modern techniques such as helical X-ray CT are recommended for the increase in the detection of early lung cancer.