[Mass screening for early lung cancer by the Miyagi method]

Mass screening for early detection of lung cancer has been in practice from 1982. Up to 1985, 583,549 persons-years have been screened. Screening was done by examining miniature X-rays taken of the chest for all those tested, and by sputum cytology for those thought to be high-risk, 34,044 persons-years. Heavy smokers over 50 years of age comprised much of the high-risk cases and persons evidencing hemoptysis. In a total of 207 detected cases of lung cancer, 120 cases were found by chest X-ray only, 69 cases were uncovered by sputum cytology only, and 18 cases were discovered by both X-ray and cytology. In one hundred and forty-four cases the cancers were resected and in 69 cases the cancers were determined to be in an early stage.