Breast Cancer in Black Women: Racial/Ethnic Disparities Affecting Survival

Racial Disparities in Receipt of Guideline-Concordant Care in Older Adults With Early Breast Cancer

Importance

Racial disparities in receipt of guideline-concordant care (GCC) among older patients with potentially curable breast cancer are understudied.

Objective

To determine whether rates of GCC, time to treatment initiation, and all-cause mortality in stage I to III breast cancer differ by race among older adults.

Design, Setting, and Participants

This cohort study used data from the National Cancer Database and included patients aged 65 years and older with stage I to III breast cancer, diagnosed between 2010 and 2019. Data analysis was conducted between July 2022 to July 2023.

Exposures

Race, defined as non-Hispanic Black or non-Hispanic White.

Main Outcomes and Measures

The primary outcome was nonreceipt of GCC, defined using the National Comprehensive Cancer Network guidelines, and all-cause mortality. The secondary outcome was time to treatment initiation. Univariate and multivariate regression analysis were used to determine association between exposure and outcomes. Models for GCC and all-cause mortality included age, stage, receptor status, year of diagnosis, Charlson-Deyo comorbidity index, insurance, health care setting, and neighborhood-level educational attainment and median income.

Results

The analytic cohort included 258 531 participants (mean [SD] age, 72.5 [6.0] years), with 25 174 participants who identified as non-Hispanic Black (9.7%) and 233 357 participants who identified as non-Hispanic White (90.3%), diagnosed between 2010 and 2017. A total of 4563 non-Hispanic Black participants (18.1%) and 35 374 non-Hispanic White participants (15.2%) did not receive GCC. Non-Hispanic Black race, compared with non-Hispanic White race, was associated with increased odds of not receiving GCC in the multivariate analysis (adjusted odds ratio [aOR], 1.13; 95% CI, 1.08-1.17; P < .001). Non-Hispanic Black race was associated with 26.1% increased risk of all-cause mortality in the univariate analysis, which decreased to 4.7%, after adjusting for GCC and clinical and sociodemographic factors (adjusted hazard ratio, 1.05; 95% CI, 1.01-1.08; P = .006). Non-Hispanic White race, compared with non-Hispanic Black race, was associated with increased odds of initiating treatment within 30 (OR, 1.65; 95% CI, 1.6-1.69), 60 (OR, 2.11; 95% CI, 2.04-2.18), and 90 (OR, 2.39; 95% CI, 2.27-2.51) days of diagnosis.

Conclusions and Relevance

In this cohort study, non-Hispanic Black race was associated with increased odds of not receiving GCC and less timely treatment initiation. Non-Hispanic Black race was associated with increased all-cause mortality, which was reduced after adjusting for GCC and clinical and sociodemographic factors. These findings suggest that optimizing timely receipt of GCC may represent a modifiable pathway to improving inferior survival outcomes among older non-Hispanic Black patients with breast cancer.

Hair product use and urinary biomarker concentrations of non-persistent endocrine disrupting chemicals among reproductive-aged Black women

BACKGROUND

Studies have shown an association between hair product use and adverse health outcomes. Scientists have hypothesized that exposure to endocrine-disrupting chemicals (EDCs) drives these associations, but few studies have directly evaluated associations between hair product use and biomarkers of EDCs. Even more limited are studies of Black women, who frequently use EDC-containing products (e.g., hair relaxers).

OBJECTIVE

We estimated associations between hair product use and EDC biomarker concentrations.

METHODS

We leveraged cross-sectional data from the Study of Environment, Lifestyle, and Fibroids, a cohort of females aged 23-34 years who self-identified as Black/African American from the Detroit-metropolitan area (USA; n = 425). On structured questionnaires, participants reported their past 24-h and past 12-month use of hair products, including relaxers/straighteners/perms, styling products, moisturizers, oils, and hair food. We quantified urinary concentrations of 19 phthalate/phthalate alternative metabolites, 7 phenols, and 4 parabens using high performance liquid chromatography isotope dilution tandem mass spectrometry. EDC biomarker concentrations were creatinine-adjusted and natural log-transformed. We used multivariable linear regression to estimate mean percent differences in EDC biomarker concentrations and 95% confidence intervals (CIs) associated with hair product use, adjusting for sociodemographic confounders.

RESULTS

Hair product use was associated with greater concentrations of multiple EDC biomarkers. Notably, use of hair products in the previous 24 h (compared with non-use) was associated with 16.2% (95% CI = 0.7%, 35.9%), 35.0% (95% CI = 2.6%, 77.6%), and 32.3% (95% CI = 8.8%, 92.0%) higher concentrations of mono-isobutyl phthalate, methyl paraben, and ethyl paraben, respectively. Use of hair relaxers/straighteners/perms, styling products, moisturizers, oils, and hair food in the past 12 months was also associated with higher concentrations of multiple phthalate, phenol, and paraben biomarkers.

CONCLUSION

Hair product use was associated with higher biomarker concentrations of multiple phthalates, phenols, and parabens. These findings suggest that hair products are potentially important exposure sources for hormonally-active chemicals among Black women.

Racioethnic Disparities in Endometrial Cancer Outcomes

Black women are twice as likely to die from endometrial cancer (EC) compared with white women. This represents one of the worst racioethnic disparities amongst all cancers globally. Compared with white women, black women are more likely to be diagnosed with advanced EC, have more barriers to accessing care and experience increased delays in obtaining an EC diagnosis and commencing treatment. Histological and molecular differences place black women at higher risk of being diagnosed with more aggressive EC subtypes that carry less favourable outcomes. Furthermore, EC diagnostic pathways are less reliable in black women, and black women are less likely to receive evidence-based treatment for EC. This racioethnic disparity in EC outcomes exists both in the UK and US, despite differences in healthcare systems. This review methodically describes the key factors along the patient journey that contribute to the disparity in black women and proposes multifaceted approaches to lessen these gaps.