Trends in incidence of invasive vaginal cancer in France from 1990 to 2018 and survival of recently diagnosed women - A population-based study.

Objective: The aim of this study was to analyze trends in the incidence of vaginal cancer in France over a 28-year period and to present survival for recently-diagnosed women.

Methods: French cancer registries provided data on invasive vaginal cancers diagnosed from 1990 to 2015 and followed up through June 2018. Trends in incidence were analyzed using a Poisson model with a bidimensional penalized spline of age and year at diagnosis. Net survival analysis was restricted to recently-diagnosed cases (2010-2015) and used a novel approach based on a bidimensional penalized spline of age and time-since-diagnosis to model excess mortality hazard.

Results: With 162 new cases estimated in France in 2018, vaginal cancer represented 0.9 % of genital cancers in French women. In 2018, the world population age-standardized incidence rate was 0.2 per 100,000 person-years, median age at diagnosis was 75 years. The standardized incidence rate decreased significantly by 3 % per year (95 % CI, -3.8; -2.2) between 1990 and 2018 (0.4 cases per 100,000 person-year in 1990, vs 0.2 in 2018). Age-standardized net survival at 1 and 5 years after diagnosis was respectively 74 % and 45 %.

Conclusions: This study confirms that vaginal cancer is still a rare malignancy in France with 5-year net survival that remains low. We observed a consistent decrease in the incidence rate between 1990 and 2018. It may be too early to attribute these trends to a positive impact of vaccination campaigns against hrHPV infection, since vaginal cancer mainly affects older women and HPV vaccination has only been available since the early 2000s, and only targets young girls.