Effectiveness of chest X-ray as a predictor of lung cancer based on lung cancer death

To evaluate the significance of chest radiograph in medical examination for lung cancer, 133 A-bomb survivors who died of lung cancer during the period from January 1972 through December 1989 were retrospectively analyzed. Lung cancer was diagnosed by chest radiographs alone in 130 A-bomb survivors (97.7%). The most common finding was tumor shadow in the pulmonary field (90 cases), followed by hilar enlargement (28), atelectasis (7), and pleural exudate (5). There was no bilateral difference in chest radiographs. In the remaining 3 lung cancer A-bomb survivors diagnosed by sputum, there was no radiographic evidence. Eighty seven A-bomb survivors had participated in the health examination before the diagnosis of lung cancer, 27 of which had had abnormal findings in the radiographs preceding the diagnosis. The previous false negative radiographs seemed to have occurred by the presence of underlying chest disease and superimposition on the normal chest structures. In cases of underlying chest disease, a comparative interpretation with previous chest radiographs may be of importance. Tumor diameter on posterior-anterior chest radiographs ranged from 1.0 to 7.5 cm, with a mean of 3.3 cm at the time of diagnosis of lung cancer. (N.K.)