Projection of the number of new lung cancer cases in the world.

Abstract

In order to compare the estimated number of lung cancer cases from 2020 to 2040 between Japan and other countries, we extracted information on reported projection of the number of new cancer cases from the ‘Global Cancer Observatory’ website (1). On this site, the predicted future cancer burden worldwide from the estimates in 2020 up until 2040 was reported. The estimates were based on the assumption that the incidence rate by sex and age group for each country in the world as of 2020, as estimated by the GLOBOCAN project (2), will remain constant until 2040. This means that the increase or decrease in the number of cancer cases will depend only on the projected population. We calculated the incremental growth rate to 2040 prediction relative to the number of cases in 2020, and showed on the figures how much the incremental growth will be for each country. Figure 1 shows the trend of estimated new cancer cases for males. In China, the incidence in 2020 is clearly high compared with other countries, about five to six times that of the USA and Japan, and is expected to increase rapidly; in 2040, the incidence will be 163.5% of that in 2020, 881 318. In all other countries, the number of new cancer cases is expected to increase. In terms of rate of increase, Uganda (+140.6%) was the fastest, followed by South Korea (+96.7%), Colombia (+92.9%), Brazil (+85.4%) and Egypt (+81.4%). In Japan, the number of new lung cancer cases diagnosed in both 2020 and 2040 is second only to that of the USA, but the rate of increase is the lowest among the countries observed, at 16.7%.