Health disparities in cancer outcomes (ethnicity, deprivation and access)

United States: the SEER 21 rate of hormone receptor-negative, HER2-negative breast cancer is 25.7 per 100,000 in non-Hispanic Black women against 13.0 in non-Hispanic White women (2019 to 2023), and non-Hispanic Black women had 2.27 times the odds of a triple-negative diagnosis in 1,151,724 cases from 2010 to 2014, with stage III and IV disease also more likely (Scott 2019); in the California registry non-Hispanic Black women with late-stage triple-negative disease had a five-year relative survival of 14 percent, the poorest of any group (Bauer 2007); basal-like tumours were found in 39 percent of premenopausal African American women against 16 percent of others (Carey 2006); and even after controlling for treatment delays, stage and socioeconomic factors, African American women with triple-negative disease remain nearly twice as likely to die of it (Howard and Olopade 2021). Whether this reflects a molecularly distinct disease or a higher incidence of aggressive biology driven by disparities has evidence on both sides (Dietze 2015); in 687 young Black women, triple-negative disease (hazard ratio 1.81) and node involvement shortened disease-free survival, full-time employment lengthened it (0.44), and a higher percentage of West African genetic ancestry shortened it within hormone receptor-positive disease (1.45), pointing to ancestry beyond self-reported race and to social determinants together (Reid 2024). United Kingdom: in the POSH cohort of women diagnosed at 40 or under, triple-negative tumours were more frequent in Black (26.1 percent) than White (18.6 percent) patients, chemotherapy use was equally high, yet five-year overall survival was 71.1 against 82.4 percent and Black ethnicity independently predicted distant relapse in ER-positive disease, despite equal access to NHS care (Copson 2014); in 116,500 women in England (2013 to 2018) all ethnic minority groups had greater adjusted odds of high-stage, high-grade or ER-negative tumours, most marked in Black African and Black Caribbean women and larger in older women (Gathani 2021). Deprivation acts alongside ethnicity: five-year survival for breast cancer in England is 82.6 percent in the most deprived group against 89.6 percent in the least (2018 to 2022), and breast cancer mortality rates in UK women are 12 percent higher in the most deprived quintile, with about 650 deaths a year linked to deprivation (Cancer Research UK). Trial enrolment does not reflect the burden, which the parent record lists among its open problems.