Abstract
BACKGROUND: Ethnic minority women are commonly reported to have more aggressive breast cancer than White women, but there is little contemporary national evidence available. METHODS: We analysed data from the National Cancer Registration and Analysis Service on women diagnosed with invasive breast cancer during 2013-2018. Multivariable logistic regression yielded adjusted odds ratios (and 95% confidence intervals) of less favourable tumour characteristics (high stage, high grade, ER negative, Her2 positive) by ethnicity (black African, black Caribbean, Indian, Pakistani and white) in younger (30-46 years) and older (53-70 years) women. RESULTS: In 24,022 women aged 30-46 at diagnosis, all ethnic minority groups apart from Indian women had a significantly greater odds of certain less favourable tumour characteristics compared to white women in fully adjusted models. In 92,555 women aged 53-70, all ethnic minorities had a significantly greater adjusted odds of several of the less favourable tumour characteristics. These differences were most marked in black African and black Caribbean women. CONCLUSIONS: Ethnic minority women are at greater risk of breast cancers with less favourable characteristics, even after allowing for age and other potential confounders. These differences are greater in older than younger women, and in the Black rather than South Asian ethnic groups.