Breast cancer: trends in international incidence in men and women
Cette étude analyse l'évolution de l'incidence du cancer du sein dans le monde, chez la femme et chez l'homme, en fonction de la distribution géographique
Background: The age-standardised incidence of breast cancer varies geographically, with rates in the highest-risk countries more than five times those in the lowest-risk countries. Methods: We investigated the correlation between male (MBC) and female breast cancer (FBC) incidence stratified by female age-group (<50 years, and 50 years) and used Poisson regression to examine male incidence rate ratios according to female incidence rates. Results: Age-adjusted breast cancer incidence rates for males and females share a similar geographic distribution (Spearman’s correlation=0.51; P<0.0001). A correlation with male incidence rates was found for the entire female population and for women aged 50 years and over. Breast cancer incidence rates in males aged <50 years were not associated with FBC incidence, whereas those in males aged 50 years were. MBC incidence displays a small ‘hook’ similar to the Clemmesen’s hook for FBC, but at a later age than the female hook. Interpretation:Further investigation of possible explanations for these patterns is warranted. Although the incidence of breast cancer is much lower in men than in women, it may be possible to identify a cause common to both men and women.