Risk factors for breast cancer in East Asian women relative to women in the West

Abstract

Abstract The incidence of breast cancer in women of East Asian ancestry (Chinese, Japanese and Korean) is lower than in women of European ancestry but is currently rising. This review explores potential reasons for this inter‐ethnic difference in incidence by profiling breast cancer risk factors reported for East Asian and Western women. Factors such as endogenous hormone exposure, lifestyle choices, diet and genetic predisposition are associated with breast cancer risk in both East Asian and Western women. However, the relative exposure to these risk factors may vary according to a woman's geographical ancestry and culture. For example, age at menarche and menopause, parity, breast‐feeding history, low fat and high soy consumption as well as the prevalence of high risk genetic alleles may vary with a woman's geographical ancestry and/or culture. Differences in exposure to these risk factors in East Asian and Western women are consistent with the inter‐ethnic differences in breast cancer incidence observed. Understanding the underlying factors contributing to differences in the profile of breast cancer across populations is important when considering screening and prevention programs for East Asian women resident in the East or the West.