Guideline-concordance along the cancer care continuum and breast cancer mortality by race and ethnicity: a SEER-Medicare study.

Effects of radiotherapy and of differences in the extent of surgery for early breast cancer on local recurrence and 15-year survival: an overview of the randomised trials

Trends in breast cancer incidence, survival, and mortality

Background: The Oncotype 21-gene Recurrence Score (RS) is the most commonly ordered genomic biomarker used to inform decisions on adjuvant chemotherapy for patients with estrogen receptor (ER)-positive, HER2-negative early breast cancer. Representation of racial/ethnic minority patients in the population used to develop the assay was poor, with only 5% of study participants identified as Black. This raises concern about the accuracy of the RS in underrepresented populations. In earlier work (Hoskins et al, JAMA Oncology 2021), we showed that the RS has less prognostic accuracy in Black compared with non-Hispanic White (NHW) women. This finding is concerning in light of persistent racial disparities in breast cancer mortality. Here we examine the predictive accuracy of the RS according to race/ethnicity for identifying patients with ER+, axillary node-negative breast cancer who benefit from adjuvant chemotherapy.Methods: We conducted a large, population-based retrospective cohort study of women 18+ years diagnosed with ER+, axillary node-negative breast cancer from 2004 to 2010 using Surveillance, Epidemiology and End Results Oncotype DX Database (2004-2015). This analysis included women with a minimum of 7 yrs follow-up and an RS of 11-25, since this is the group with the most uncertainty regarding the benefit of chemotherapy. Demographic and clinical characteristics were collected from cancer registry data. Propensity score weighted Cox models determined the association between chemotherapy use and breast cancer death. Age, insurance status, tumor grade, tumor size, progesterone receptor status, and RS were included as predictors of the propensity score. Associations between chemotherapy use and breast cancer death were determined using overall, race/ethnicity, and age stratum-specific hazard ratios (HR) and 95% confidence intervals (CI). Results: The analysis included 22,693 NHW, 5,657 Black, and 3,348 Hispanic women. The overall result is consistent with the prospective TAILORx trial, showing greater benefit from chemotherapy in women under age 50. There is a greater reduction in the hazard of breast cancer death associated with chemotherapy use for Black (HR 0.31, 95% CI, 0.15, 0.66) and Hispanic (HR 0.07, 95% CI, 0.02, 0.31) compared with NHW women under age 50 (HR 0.43, 95% CI,0.32, 0.59). In models combining Black and NHW patients, an interaction term for race*chemotherapy was significant (p=0.022), indicating a differential association between chemotherapy use and breast cancer death according to race/ethnicity. Visual comparison of breast cancer mortality curves that plot 7-year breast cancer death rate as a function of the continuous RS, stratified by chemotherapy administration (yes/no), shows that the curves begin to diverge at a lower RS for Black (RS 17) compared with NHW women (RS 24). Conclusions: This observational study found that Black women under age 50 with ER+, axillary node-negative breast cancer and an RS of 11-25 derive significantly more benefit from adjuvant chemotherapy than NHW women. National practice guidelines do not recommend routine use of adjuvant chemotherapy for patients in this risk category, indicating that many Black patients may be undertreated. Results need to be confirmed in prospective studies, but they suggest that RS cut-offs used to recommend adjuvant chemotherapy may need to be modified for racial/ethnic minority women. Hazard of Breast Cancer Death (95% Confidence Interval)Race/EthnicityChemotherapyAll AgesAge < 50Age 50+OverallYes0.71 (0.63, 0.81)0.32 (0.25, 0.41)1.01 (0.87, 1.18)NoRefRefRefNHWYes0.73 (0.62,0.84)0.43 (0.32, 0.59)0.87 (0.74, 1.04)NoRefRefRefBlackYes0.83 (0.60, 1.16)0.31 (0.15, 0.66)1.26 (0.84, 1.89)NoRefRefRefHispanicYes0.33 (0.20, 0.57)0.07 (0.02, 0.31)0.61 (0.33, 1.12)NoRefRefRef Citation Format: Hsiao- Ching Huang, Gregory S. Calip, Jennifer Weiss, Yael Simons, V.K. Gadi, Oana C. Danciu, Garth H. Rauscher, Kent F. Hoskins. Racial/ethnic differences in the benefit of adjuvant chemotherapy for breast cancer patients with an intermediate risk 21-gene recurrence score [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-14-02.

The benefits and harms of breast cancer screening – Authors' reply

e18556 Background: Considerable efforts to improve disparities in breast cancer outcomes for underserved women have occurred over the past 3 decades. This study was conducted to evaluate trends in survival, by race-ethnicity, for women diagnosed with breast cancer in Florida over a 26-year period to assess potential improvement in racial-ethnic disparities. Methods: This was a retrospective cohort study of women diagnosed with invasive breast cancer in Florida between 1990-2015. Data were obtained from the Florida Cancer Data System. Women in the study were categorized according to race (white/black) and Hispanic ethnicity (yes/no) as non-Hispanic white (NHW), non-Hispanic black (NHB), Hispanic white (HW), and Hispanic black (HB). Cumulative incidence estimates of 5- and 10-year breast cancer death with 95% confidence intervals (CI) were obtained by race-ethnicity, according to diagnosis year. Subdistribution hazard models were used to obtain subdistribution hazard ratios (sHR) for the relative rate of breast cancer death accounting for competing causes. Results: Compared to NHW women, minority women were more likely to be younger, be uninsured or have Medicaid as health insurance, live in high poverty neighborhoods, have more advanced disease at diagnosis, have high grade tumors, have hormone receptor negative tumors, and receive chemotherapy as treatment. Minority women were less likely to receive surgery. Over the course of the study, breast cancer mortality decreased for all racial-ethnic groups, and racial-ethnic minorities had greater absolute and relative improvement in breast cancer survival for nearly all metrics compared to non-Hispanic white (NHW) women. However, for the most recent time period (2010-2015), black women still experienced significant survival disparities with non-Hispanic black (NHB) women having twice the rate of 5-year (sHR = 2.04: 95% CI; 1.91-2.19) and 10-year (sHR = 2.02: 95% CI; 1.89-2.16) breast cancer death. Conclusions: Despite efforts to improve disparities in breast cancer outcomes for underserved women in Florida, additional targeted approaches are needed to reduce the poorer survival in black (especially NHB) women. Our next step is to conduct a mediation analysis of the most important factors driving racial/ethnic disparities in breast cancer outcomes for women in Florida.

While cancer deaths have decreased nationally, declines have been much slower in rural areas than in urban areas. Previous studies on rural cancer service capacity are limited to specific points along the cancer care continuum (eg screening, diagnosis or treatment) and require updating to capture the current rural health landscape since implementation of the 2010 Affordable Care Act in the USA. The association between current rural cancer service capacity across the cancer care continuum and cancer incidence and death is unclear. This cross-sectional study explored the association between breast cancer service capacity and incidence and mortality in Arizona's low populous counties. To measure county-level cancer capacity, clinical organizations operating within low populous areas of Arizona were surveyed to assess on-site breast cancer services provided (screening, diagnosis and treatment) and number of healthcare providers were pulled from Centers for Medicare and Medicaid Services National Provider Identifier database. The number of clinical sites and healthcare providers were converted to county-level per capita rates. Rural-Urban Continuum codes were used to designate rural or urban county status. Age-adjusted county-level breast cancer incidence and death rates from 2010 to 2016 were obtained from the Arizona Department of Health Services, Arizona Cancer Registry. Descriptive statistics were used to summarize the results. Multivariate regression was used to evaluate the association between cancer service capacity and incidence and mortality in 13 out of Arizona's 15 counties. Rural counties had more per capita clinical sites (20.4) than urban counties (8.9) (p=0.02). Urban counties had more per capita pathologists (1.0) than rural counties (0) (p≤0.01). In addition to zero pathologists, rural counties had zero medical oncologists. Rural county status was associated with a decrease in breast cancer incidence (β=-20.1, 95% confidence interval: -37.2-3.1). While Arizona's sparsely populated rural counties may have more physical infrastructure per capita, these services are dispersed over vast geographic areas. They lack specialists providing cancer services. Non-physician clinical providers may be more prevalent in rural areas and represent opportunities for improving access to cancer preventive services and care. Compared to urban counties, rural county status was associated with lower detected breast cancer incidence rates although there were no statistically significant differences in breast cancer mortality. Other factors may contribute to rural-urban differences in breast cancer incidence. Future research should explore these factors and the association between cancer capacity and local resources because the use of county-level data represents a challenge in Arizona, where counties average over 19 425 km2 (7500 square miles).

68 CA A Cancer Journal for Clinicians Since the publication of the results of the Greater New York Trial and the Swedish Two-County Trial in the 1970s and 1980s, there has been a general consensus that screening for breast cancer with mammography reduces mortality from the disease. The results of these pioneering trials for the most part have been subsequently confirmed by later trials in Sweden, Canada, and the United Kingdom. Although some issues endure, most notably those regarding cost-effectiveness of screening in particular age groups, as well as concerns about harms associated with false positive results, the evidence that screening reduces deaths from breast cancer has steadily increased, and the consensus regarding the benefit of screening has grown stronger. The evidence that screening with mammography is associated with a lower breast cancer death rate recently was challenged when The Lancet published a research letter by Olsen and Gotzsche (OG) describing their overview of the mammographic screening trials. OG asserted that “...the reliable evidence does not indicate any survival benefit of mass screening for breast cancer,” and they maintained that screening leads to more aggressive treatment; thus, screening is not only without benefit, but in addition to representing a waste of health resources, it actually results in net harms. This article has generated considerable print and electronic media attention, with a spectrum of opinions ranging from complete support for the conclusions of OG to complete dissent.Yet, despite the public exchange, the OG report has failed to convince institutional leaders in the United Kingdom, Sweden, the Netherlands, or the United States to change screening policy. Most have publicly reaffirmed the current recommendations supporting regular mammography. Having thoroughly considered all available information, including the OG report, the US Preventive Services Task Force retained its current recommendation that women have regular mammograms every one to two years, and in fact, expanded the recommendation to include women in their forties. In addition, 10 leading medical organizations published a full-page open letter in the New York Times on January 31, 2002, supporting the value of early breast cancer detection. In our opinion, which is based on evidence accrued over decades of scientific research on breast cancer screening, and countless, independent expert peer reviews of the study designs, data, and conclusions of the trials, the scientific foundation for the value of early breast cancer detection with mammography is sound.To see why, consider Figure 1, which summarizes the most recently published results of the mammographic screening trials.The results indicate that there is a statistically significant 24% reduction in breast cancer mortality associated with an invitation to screening. The distinction between “invited to screening” versus “screened” becomes clear when you consider that a randomized trial of screening examines mortality rates in the study arm offered screening versus the study arm offered usual care. Mr. Duffy is Principal Scientist, Cancer Research UK, London, England.

Background: Black women have the highest breast cancer (BC) mortality rate of any race group in the US. The disparity is often attributed to a higher prevalence of poor prognostic factors, such as estrogen receptor (ER)−negative tumors. However, racial disparities in BC survival are worse for patients with ER−positive tumors. Determining whether the BC mortality disparity is driven by the higher prevalence of poor prognostic factors or worse post-diagnosis survival can guide needed interventions. Methods: Incident case counts and survival data for non-Hispanic Black (NHB) and non-Hispanic White (NHW) patients diagnosed with invasive BC between 31 to 84 years old during 2010 to 2019 were obtained from the US Surveillance, Epidemiology, and End Results (SEER)-17 cancer registries. We calculated age-standardized incidence-based mortality (IBM) rates for both NHB and NHW women in 2019 using patient data and the 2019 population-at-risk data from SEER. We used a counterfactual framework to estimate the Black-White ratios of IBM (IBMBW) assuming equal distributions of ER status or equal hazard rates of BC death (overall and by ER status) among NHB and NHW women. Results: We included 50,922 NHB and 305,642 NHW BC cases in our analysis. Compared with NHW patients, NHB patients were more likely to have ER−negative tumors (28% vs. 15%). The estimated IBM rate per 100,000 for NHB women was 41.4 compared with 24.8 for NHW women (IBMBW = 1.67). When assuming equal distributions of ER status, IBMBW decreased from 1.67 to 1.43. When assuming equal hazard rates among NHB and NHW patients, regardless of ER status, IBMBW decreased from 1.67 to 0.87. Conclusion: Our preliminary results suggest the racial disparity in BC mortality can be eliminated when survival rates, but not subtype distribution, are matched among NHB and NHW patients, underscoring the importance of post-diagnosis survival for mitigating racial disparities. Citation Format: Maret L. Maliniak, Jeffrey M. Switchenko, Leah Moubadder, Rebecca Nash, Lindsay J. Collin, Lauren E. McCullough. Using a counterfactual framework to understand the underlying causes of Black-White racial disparities in breast cancer mortality in the US [abstract]. In: Proceedings of the 18th AACR Conference on the Science of Cancer Health Disparities; 2025 Sep 18-21; Baltimore, MD. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2025;34(9 Suppl):Abstract nr A076.

To examine racial-ethnic variation in adherence to established quality metrics (NCCN guidelines and ASCO quality metrics) for breast cancer, accounting for individual-, facility-, and area-level factors. Data from women diagnosed with invasive breast cancer at 66+ years of age from 2000 to 2017 were examined using SEER-Medicare. Associations between race and ethnicity and guideline-concordant diagnostics, locoregional treatment, systemic therapy, documented stage, and oncologist encounters were estimated using multilevel logistic regression models to account for clustering within facilities or counties. Black and American Indian/Alaska Native (AIAN) women had consistently lower odds of guideline-recommended care than non-Hispanic White (NHW) women (Diagnostic workup: ORBlack 0.83 (0.79-0.88), ORAIAN 0.66 (0.54-0.81); known stage: ORBlack 0.87 (0.80-0.94), ORAIAN 0.63 (0.47-0.85); seeing an oncologist: ORBlack 0.75 (0.71-0.79), ORAIAN 0.60 (0.47-0.72); locoregional treatment: ORBlack 0.80 (0.76-0.84), ORAIAN 0.84 (0.68-1.02); systemic therapies: ORBlack 0.90 (0.83-0.98), ORAIAN 0.66 (0.48-0.91)). Commission on Cancer accreditation and facility volume were significantly associated with higher odds of guideline-concordant diagnostics, stage, oncologist visits, and systemic therapy. Black residential segregation was associated with significantly lower odds of guideline-concordant locoregional treatment and systemic therapy. Rurality and area SES were associated with significantly lower odds of guideline-concordant diagnostics and oncologist visits. This is the first study to examine guideline-concordance across the continuum of breast cancer care from diagnosis to treatment initiation. Disparities were present from the diagnostic phase and persisted throughout the clinical course. Facility and area characteristics may facilitate or pose barriers to guideline-adherent treatment and warrant future investigation as mediators of racial-ethnic disparities in breast cancer care.

Age-Specific Analyses of Breast Cancer Versus Heart Disease Mortality in Women

Breast cancer poses a serious public health concern throughout the world in both developed and developing nations. Recent data show a small decline in breast cancer mortality in the United States and Northern Europe where the disease has been a leading cause of death.' This reduction has been attributed in part to the early detection of breast cancer in addition to advances in clinical management. The decline in mortality has also been postulated to be due to a decreased risk in women developing breast cancer in the last 2 decades associated with increased fertility as part of the post-Second World War baby boom. 1 Despite these encouraging results, other European nations such as Spain, Portugal, Greece, Hungary, Poland and Italy have not reported a reduction in breast cancer mortality. The true reasons for these breast cancer trends, particularly across continents, remain perplexing to both epidemiologists and clinicians. Any observed variation of incidence and oncologic outcome between different populations and ethnic backgrounds may relate to the underlying biological behavior of breast cancer at the cellular and molecular level. Application of biomarker studies could therefore enhance the information obtained from classical study designs and further expand the areas of scientific inquiry to which epidemiology can contribute. This approach may yield important clues in breast cancer pathogenesis, develop potential preventive strategies, improve early detection and treatment of disease with distinctive protocols, tailored to the needs of individual target populations. Conclusions from the workshop on Multicultural Aspects of Breast Cancer Etiology in Washington DC by the Etiology working group of the National Action Plan on Breast Cancer (NAPBC) in March 1999 highlighted the importance of ethno-oncology that addresses the comparison of population groups with extreme differences in the rates of incidence, mortality and survival. 2 This article reviews the evidence for global multiethnic differences in breast cancer outcome and discusses the future clinical implications of ethno-oncology.

Mammography for Older Women?

Postmastectomy radiotherapy in patients with breast cancer – Authors' reply

While the Breast Cancer Risk Assessment Tool (BCRAT) predicts breast cancer incidence, the model's performance, re-purposed to predict breast cancer mortality, is uncertain. Therefore, we examined whether the BCRAT model predicts breast cancer mortality in postmenopausal women in the Women's Health Initiative (WHI). BCRAT 5-year breast cancer incidence risk estimates were calculated for 145,408 women (aged 50-79years) enrolled in the WHI at 40 US clinical centers to examine associations of BCRAT risk groups (< 1%, 1-< 3%, ≥ 3%) with breast cancer mortality using Cox proportional regression modeling in all participants and in those with incident breast cancer. Women with BCRAT ≥ 3% risk, compared to women with BCRAT < 1% risk, were older (age 70-79years: 38.3% versus 5.3%), less commonly Black (1.1% versus 40.2%), and had stronger breast cancer family history. With 20-years follow-up, considering all participants, with 8,849 breast cancers and 1,076 breast cancer deaths, breast cancer mortality in BCRAT group ≥ 3% was not higher versus BCRAT group < 1% (Hazard Ratio [HR] 1.06 95% Confidence Interval [CI] 0.80-1.40): percent without 20-year breast cancer mortality; 99.4% [group < 1%] and 98.8% [group ≥ 3%]. Considering women with incident breast cancer, breast cancer mortality was also not higher in BCRAT group ≥ 3% versus BCRAT group < 1% (HR 1.07 95% CI 0.79-1.45). The BCRAT model, at ≥ 3% 5-year incidence risk (US guideline threshold for chemoprevention), does not identify women with higher breast cancer mortality risk, with implications for breast cancer prevention strategies.

Widespread use of screening mammography has been the mainstay of breast cancer prevention in the United States for the past 25 years. In this issue, the USPSTF has made major changes to its recomme...