Detection of early lung cancer: Results of radiologic and cytologic screening in the Miyagi program.

Abstract

Eighty-eight lung cancers including 82 primary and 6 metastatic tumors were detected by chest X-ray examination of a total of 363,320 participants in Miyagi Prefecture in Japan during 3 years period from 1982 to 1984. Sputum cytology was performed in the high-risk group (above 50 years of age with cigarette index above 600) of the total participants during the same period. This detected 67 patients with malignant tumors including 5 with cancer of the upper respiratory tract and 62 with primary lung cancer. Fifty-one of 67 cancers (82.3%) detected by sputum cytology were radiographically occult lung cancers. The annual ratio of the detection of lung cancer was 45/100,000 in the first year, however, it decreased to 38/100,000 in the second year and to 15/100,000 in the third year. Cancer resection was performed in 63.6%, 76.1% and 80.0% of the patients, in the first, the second and the third year, respectively. On the average, 57% of the patients who underwent cancer resection demonstrated early lung cancer. Especially, 45 of 51 patients with lung cancer detected by sputum cytology underwent tumor resection, of which 40 (89%) bore early lung cancer.