Mass screening for early detection of lung cancer Part 1. The effectiveness of mass screening for lung cancer: Improvement in survival shown by long-term follow-up

In an attempt to evaluate the effectiveness of mass screening for lung cancer, survival was compared between 276 patients with lung cancer detected by mass screening (mass screening group) and 265 patients detected by cancer-related symptoms (symptomatic group) from 1976 to 1984. In the mass screening group 61% of the patients were Stage I, while in the symptomatic group only 27% were Stage I (p<0.01). The resectability and curative resection rate in the mass screening group were 63% and 43%, respectively, significantly higher than the 38% and 21% rates in the symptomatic group (p<0.01). The 5-year survival rate in the mass screening group was 34%, compared to 17% in the symptomatic group (p<0.001). These results indicate that mass screening for lung cancer results in earlier detection and improved prognosis.