The influence of lung cancer mass screening on surgical results

After the introduction of the mass screening program for lung cancer, the number of patients detected by mass screening increased as well as the number of early staged patients. Therefore, we examined the influence of lung cancer mass screening on surgical results.

A total of 1177 primary lung cancer cases, who underwent surgery from 1963 to 1992, were retrospectively reviewed. They were grouped according to the changes in the mass screening system: the first period (1963-1977) before lung cancer screening started, the second period (1978-1986) when mass screening was conducted by the local government, and the third period (1987-1992) after the launching of the national screening program.

The rate of cases detected by mass screening increased over time and the 5-year survival rate improved significantly, from 33.7% in the first period, to 51.8% in the second period and finally, to 58.4% in the third period. The improvement is attributable to a relative increase of rate of stage I cases and better stage I survival rate. Specifically, in stage I cases, improvement resulted from a relative increase of stage IA in peripheral type and roentgenographically occult lung cancer cases and from better survival rate of these two groups.

As lung cancer screening has come into widespread use, detection of peripheral small-sized lung cancer and roentgenographically occult lung cancer have increased and consequently, surgical results have improved.