Racial Disparities in Breast Cancer Diagnosis and Treatment by Hormone Receptor and HER2 Status

Abstract

Background African American and Hispanic women are more likely to be diagnosed with aggressive forms of breast cancer. Disparities within each subtype of breast cancer have not been well documented. Methods Using data from 18 SEER cancer registries, we identified 102,064 women aged 20 years or older, diagnosed with invasive breast cancer in 2010–2011, and with known stage, hormone receptor (HR) and HER2 status. Associations between race/ethnicity and cancer stage and receipt of guideline concordant treatment were evaluated according to HR/HER2 status. Results Overall, African American and Hispanic women were 30–60% more likely to be diagnosed with stage II–IV breast cancer compared to Non-Hispanic whites. African American women had 40–70% higher risks of stage IV breast cancer across all four subtypes. American Indian/Alaska Native women had a 3.9-fold higher risk of stage IV triple negative breast cancer. African American and Hispanic whites were 30–40% more likely to receive non-guideline concordant treatment for breast cancer overall and across subtypes. Conclusions Women in several racial/ethnic groups are more likely to be diagnosed with more advanced stage breast cancer. African American and American Indian/Alaska native women in particular had the highest risk of being diagnosed with stage IV triple negative breast cancer. African American and Hispanic women were also consistently at higher risk of not receiving guideline concordant treatment across subtypes. Impact These findings provide important characterization of which subtypes of breast cancer racial/ethnic disparities in stage and treatment persist.

Contribution of clinical and socioeconomic factors to differences in breast cancer subtype and mortality between Hispanic and non-Hispanic white women

“…Relative to NHW women, Hispanics are more likely to be diagnosed with later stage breast cancers and larger tumors [2, 5, 6], factors that contribute to lower survival [3, 4]. There is also evidence that Hispanic women have higher proportions of the more aggressive tumor subtypes, including triple-negative and HER2-overexpressing tumors [5, 7–10]. Further, Hispanic patients are less likely to receive guideline concordant cancer treatment and experience poorer quality of life after diagnosis as compared to NHW women [7, 11].…”

“…There is also evidence that Hispanic women have higher proportions of the more aggressive tumor subtypes, including triple-negative and HER2-overexpressing tumors [5, 7–10]. Further, Hispanic patients are less likely to receive guideline concordant cancer treatment and experience poorer quality of life after diagnosis as compared to NHW women [7, 11]. Hispanics in general are of lower socioeconomic status (SES) and are less likely to have health insurance [12], factors that independently impact cancer survival.…”

Multilevel Intervention Raises Latina Participation in Mammography Screening: Findings from ¡Fortaleza Latina!

“…Of the 542 enrolled women, an additional 6 were excluded after the follow-up survey, because of age (3), mammography history (1), or other reasons (2). This resulted in 536 eligible women.…”

“…Data from 2012 from the Surveillance, Epidemiology and End Results (SEER) program revealed that 42% of incident breast cancer cases in Latinas were detected in regional or distant stages, compared to 35% in non-Latina whites (1). Indeed, recent analysis of data from 18 SEER cancer registries in the United States showed that, among women diagnosed with breast cancer, Latinas were 30% more likely to be diagnosed with stages II and III (vs. stage I), compared to non-Latina whites (3). The advanced stage of disease detection is thought to be attributable in part to higher occurrence of poor prognosis subtypes of breast cancer and lower rates of screening mammography; national data for women ages 50-74 show a 5% lower rate of mammography participation in the previous 2 years among Latinas, compared to non-Latina whites (69% vs. 74%) (4).…”

Consideration of geographic context in breast cancer in African American women

“…As breast cancer subtype data have become more accessible, researchers have examined the role of race and socioeconomic status in breast cancer subtype at the population level. [7][8][9] However, with the exception of the aforementioned article by Kohler et al, to my knowledge there is only limited research regarding population-level, geographic differences in breast cancer subtypes, especially the triple-negative subtype. 7 This suggests that geography may be an important additional factor that interplays with the cultural, social, economic, and biological factors indicated by Williams et al 1 In their study, Williams et al provide a thoughtful review of the social context of breast cancer for African American women.…”