Initial Evidence of a Possible Effect of HPV Vaccination on Cancer Incidence in Germany.

Abstract

Infection with human papillomavirus (HPV) is one of the more common sexually transmitted diseases in Germany. Vaccination against HPV was introduced in Germany in 2007. In this study, we sought to detect a population-based decline in the incidence of cervical cancer in women under age 30 who were eligible for vaccination in the first 11 years after its introduction. Data on new diagnoses of HPV-associated cervical cancer from 2004 to 2018 were obtained from the cancer registries of the German federal states (Bundesländer) through the German Center for Cancer Registry Data (ZfKD). Trends in the incidence of invasive and in situ cervical cancer were determined with log-linear joinpoint regression and age-period-cohort models. The incidence of cervical cancer, which had been rising in the previous decades, has been falling since 2010, with a marked decline among women in all age groups eligible for vaccination (e.g., from 70.0 to 41.8 cases per 100 000 persons per year from 2010 to 2018 in women aged 24 to 26). Women born in 1992 were the first to become eligible for vaccination and have a 24% lower incidence than the reference cohort of women born in 1989 (relative risk 0.76, 95% confidence interval [0.68; 0.86]). Larger effects were found in later birth cohorts, in which vaccination was more widespread. Eleven years after the introduction of HPV vaccination, a drop in the incidence of cervical cancer was observable at the population level in the birth cohorts eligible for vaccination.