In Japan, the incidence of cervical cancer has increased since the late 1990s, especially in young women, despite a decreasing trend in most developed countries. A new study by scientists from the International Agency for Research on Cancer (IARC) and partners compares the time trends of cervical cancer incidence rates in Japan to those in the Republic of Korea and in Japanese-Americans in 1985–2012. The study, published in the International Journal of Cancer, used population-based cancer registries and analysed the data using joinpoint regression and age–period–cohort models.
The results showed that the overall age-adjusted incidence rates in Japan decreased by 1.7% per year until 1997 and thereafter increased by 2.6% per year. The increase in the incidence rate was observed mainly in premenopausal women, with increases of 5% in women in their 20s, of 3% in women in their 30s, and of 2% in women in their 40s.
The incidence rates for women born before 1920 and after 1970 were about double those for women born in the late 1930s and 1940s. Increasing risk in recent birth cohorts was not observed in Japanese-Americans or women in the Republic of Korea. The trends in Japan may be attributable to increasing prevalence of human papillomavirus (HPV) infection among young women, underscoring the urgent need for effective cancer control, including resuming proactive recommendation of HPV vaccination and improving the Japanese cervical cancer screening programme.
Utada M, Chernyavskiy P, Lee WJ, Franceschi S, Sauvaget C, de Gonzalez AB, et al.
Increasing risk of uterine cervical cancer among young Japanese women: Comparison of incidence trends in Japan, South Korea and Japanese-Americans between 1985 and 2012
Int J Cancer, 2019, 144(9):2144–2152; https://doi.org/10.1002/ijc.32014