Analysis of lung cancer incidence, mortality trends, and smoking rates in Japan:1975-2022 with insights on the impact of COVID-19.

In Japan, high-quality cancer statistics are collected through cancer registries. However, these data are rarely summarized or reported in research articles. We compiled statistical data on lung cancer in Japan including the COVID-19 pandemic. In 2019, the number of cases of lung cancer in Japan was 126,548. The age-adjusted incidence rate of lung cancer increased from 23.2/100,000 to 42.4/100,000 in males and from 7.2/100,000 to 18.3/100,000 in females between 1975 and 2019. The age-adjusted mortality rate of lung cancer in Japan increased since 2000, after which it decreased. This trend was similar in both males and females. We also investigated statistics on lung cancer worldwide (Australia, Sweden, England, and the United States [USA]). The age-adjusted incidence rate of lung cancer in the data standardized to the world population for males has increased only in Japan; for females, it has decreased only in the USA. Global age-adjusted lung cancer mortality rates have been declining in all countries. In addition, the COVID-19 pandemic has not affected the age-adjusted mortality rate of lung cancer. On the other hand, the number of individuals undergoing lung cancer screening in Japan decreased from 7.92 million in 2019 to 6.59 million in 2020. The COVID-19 pandemic may have affected individuals undergoing lung cancer screening, and its impact on lung cancer needs to be continuously monitored in the future.