Future Prediction of Lung Cancer Screening by Lung Cancer Screening Computed Tomography (LSCT) in Comparison with Present Screening by Chest X-ray

Abstract

Objective. We predict the reduction of lung cancer mortality in Japan in the year 2025 employing LSCT screening and propose a realistic method to achieve this goal. Methods. Using the data of LSCT screening in Japan and a deterministic model of cancer screening developed by the author, the relative risk of death of the screened group and of the non-screened group is calculated. Then the incidence of lung cancer in 2025 is estimated from population statistics and age-specific incidence rates. The number of lung cancer deaths at 2025 is calculated using the model assuming 50% of Japanese of 40-84 years old undergo the annual LSCT screening. Results. The incidence of lung cancer is predicted to be 74,982 men and 29,616 women in 2025 for all ages and the figures for the 40-84-year-old group are 62,982 men and 21,314 women. The incidence shows a 50% increase compared with 2002. If LSCT screening is performed on 50% of the population aged 40-84 years, the numbers of deaths due to lung cancer are expected to be 51,738 men and 21,326 women. The relative risk rates compared with the non-screened group are 0.77 for men and 0.80 for women. Conclusion. It is possible to reduce the lung cancer mortality in Japan by 22%, if we can perform LSCT screening in more than 50% of the population aged 40-84 years old in 2025.