Racial/ethnic differences in the utilization of chemotherapy among stage I-III breast cancer patients, stratified by subtype: Findings from ten National Program of Cancer Registries states

Racial disparities in outcomes of patients with stage I-III triple-negative breast cancer after adjuvant chemotherapy: a post-hoc analysis of the E5103 randomized trial

PURPOSE

Breast cancer mortality is higher in Black women than other racial groups. This difference has been partially attributed to a higher proportion of triple-negative breast cancer (TNBC). However, it is uncertain if survival disparities exist in racially diverse TNBC patients receiving similar treatments. Here, we examine racial differences in disease-related outcomes in TNBC patients treated on the E5103 clinical trial.

METHODS

From 2007 to 2011, 4,994 patients with stage I-III HER2-negative breast cancer were randomized to adjuvant chemotherapy with or without bevacizumab. This analysis was limited to the subset of 1,742 TNBC patients with known self-reported race. Unadjusted Kaplan-Meier curves and adjusted Cox-Proportional Hazards models were used to determine breast cancer events and survival outcomes.

RESULTS

Of the analysis population, 51 (2.9%) were Asian, 269 (15.4%) Black, and 1422 (81.6%) White. Median age was 51 years. Patient characteristics, treatment arm, and local therapies were similar across racial groups. White women were more commonly node-negative (56% vs. 49% and 44% in Asian and Black women, respectively; p < 0.01). At a median follow-up of 46 months, unadjusted Kaplan-Meier locoregional and distant recurrence, and disease-free and overall survival, did not differ significantly by race. In Cox models adjusted for patient and tumor characteristics and treatment arm, race was not associated with any disease event. Larger tumor size and nodal involvement were consistently associated with breast cancer events.

CONCLUSION

This clinical trial population of similarly treated TNBC patients showed no racial differences in breast cancer outcomes. Disease extent, rather than race, was associated with disease events.

Racial disparities in breast cancer risk factors and risk management

Racial disparities in breast cancer outcomes are well described across the spectrum of screening, diagnosis, treatment, and survivorship. Breast cancer mortality is markedly elevated for Non-Hispanic Black women compared with other racial and ethnic groups, with multifactorial causes. Here, we aim to reduce this burden by identifying disparities in breast cancer risk factors, risk assessment, and risk management before breast cancer is diagnosed. We describe a reproductive profile and modifiable risk factors specific to the development of triple-negative breast cancer. We also propose that screening strategies should be both risk- and race-based, given the prevalence of early-onset triple-negative breast cancer in young Black women. We emphasize the importance of early risk assessment and identification of patients at hereditary and familial risk and discuss indications for a high-risk referral. We discuss the subtleties following genetic testing and highlight "uncertain" genetic testing results and risk estimation challenges in women who test negative. We trace aspects of the obesity epidemic in the Black community to infant feeding patterns and emphasize healthy eating and activity. Finally, we discuss building an environment of trust to foster adherence to recommendations, follow-up care, and participation in clinical trials. Addressing relevant social determinants of health; educating patients and clinicians on factors impacting disparities in outcomes; and encouraging participation in targeted, culturally sensitive research are essential to best serve all communities.

Temporal Association Rule Mining: Race-Based Patterns of Treatment-Adverse Events in Breast Cancer Patients Using SEER-Medicare Dataset

PURPOSE

Disparities in the screening, treatment, and survival of African American (AA) patients with breast cancer extend to adverse events experienced with systemic therapy. However, data are limited and difficult to obtain. We addressed this challenge by applying temporal association rule (TAR) mining using the SEER-Medicare dataset for differences in the association of specific adverse events (AEs) and treatments (TRs) for breast cancer between AA and White women. We considered two categories of cancer care providers and settings: practitioners providing care in the outpatient units of hospitals and institutions and private practitioners providing care in their offices.

PATIENTS AN METHODS

We considered women enrolled in the Medicare fee-for-service option at age 65 who qualified by age and not disability, who were diagnosed with breast cancer with attributed patient factors of age and race, marital status, comorbidities, prior malignancies, prior therapy, disease factors of stage, grade, and ER/PR and Her2 status and laterality. We included 141 HCPCS drug J codes for chemotherapy, biotherapy, and hormone therapy drugs, which we consolidated into 46 mechanistic categories and generated AE data. We consolidated AEs from ICD9 codes into 18 categories associated with breast cancer therapy. We applied TAR mining to determine associations between the 46 TR and 18 AE categories in the context of the patient categories outlined. We applied the spark.mllib implementation of the FPGrowth algorithm, a parallel version called PFP. We considered differences of at least one unit of lift as significant between groups. The model's results demonstrated a high overlap between the model's identified TR-AEs associated set and the actual set.

RESULTS

Our results demonstrate that specific TR/AE associations are highly dependent on race, stage, and venue of care administration.

CONCLUSIONS

Our data demonstrate the usefulness of this approach in identifying differences in the associations between TRs and AEs in different populations and serve as a reference for predicting the likelihood of AEs in different patient populations treated for breast cancer. Our novel approach using unsupervised learning enables the discovery of association rules while paying special attention to temporal information, resulting in greater predictive and descriptive power as a patient's health and life status change over time.

Disparities in OncotypeDx Testing and Subsequent Chemotherapy Receipt by Geography and Socioeconomic Status

BACKGROUND

OncotypeDx is a prognostic and predictive genomic assay used in early-stage hormone receptor-positive, HER2- (HR+/HER2-) breast cancer. It is used to inform adjuvant chemotherapy decisions, but not all eligible women receive testing. We aimed to assess variation in testing by demographics and geography, and to determine whether testing was associated with chemotherapy.

METHODS

For 1,615 women in the Carolina Breast Cancer Study with HR+/HER2-, Stage I-II tumors, we estimated prevalence differences (PD) and 95% confidence intervals (CI) for receipt of OncotypeDx genomic testing in association with and sociodemographic characteristics. We assessed associations between testing and chemotherapy receipt overall and by race. Finally, we calculated the proportion of eligible women receiving OncotypeDx by county-level rurality, census tract-level socioeconomic status, and Area Health Education Center regions.

RESULTS

38% (N = 609) of potentially eligible women were tested, with lower testing prevalences in Black (31%; PD, -11%; 95% CI, -16%-6%) and low-income women (24%; PD, -20%; 95% CI, -29% to -11%) relative to non-Black and higher income women. Urban participants were less likely to be tested than rural participants, though this association varied by region. Among women with low genomic risk tumors, tested participants were 29% less likely to receive chemotherapy than untested participants (95% CI, -40% to -17%). Racial differences in chemotherapy were restricted to untested women.

CONCLUSIONS

Both individual and area-level socioeconomics predict likelihood of OncotypeDx testing.

IMPACT

Variable adoption of OncotypeDx by socioeconomics and across geographic settings may contribute to excess chemotherapy among patients with HR+/HER2- cancers. See related In the Spotlight, p. 635.

Patterns of chemotherapy receipt among patients with hormone receptor-positive, HER2-negative breast cancer

BACKGROUND

Breast cancer chemotherapy utilization not only may differ by race and age, but also varies by genomic risk, tumor characteristics, and patient characteristics. Studies in demographically diverse populations with both clinical and genomic data are necessary to understand potential disparities by race and age.

METHODS

In the Carolina Breast Cancer Study Phase 3 (2008-2013), chemotherapy receipt (yes/no) and regimen type were assessed in association with age and race among hormone receptor (HR) positive and HER2-negative tumors (n = 1862). Odds ratios were estimated for the association between demographic factors and chemotherapy receipt.

RESULTS

Monotonic decreases in frequency of adjuvant chemotherapy receipt were observed over time during the study period, while neoadjuvant chemotherapy was stable. Younger age was associated with chemotherapy receipt (OR [95% CI]: 2.9 [2.4, 3.6]) and with anthracycline-based regimens (OR [95% CI]: 1.7 [1.3, 2.4]). Participants who had Medicaid (OR [95% CI]: 1.8 [1.3, 2.5]), lived in rural settings (OR [95% CI]: 1.4 [1.0, 2.0]), or were Black (OR [95% CI]: 1.5 [1.2, 1.8]) had slightly higher odds of chemotherapy, but these associations were non-significant with adjustment for stage and grade. Associations between younger age and chemotherapy receipt were strongest among women who did not receive genomic testing.

CONCLUSIONS

While race was not strongly associated with chemotherapy receipt, younger age remains a strong predictor of chemotherapy receipt, even with adjustment for clinical factors and among women who receive genomic testing.

Population simulation modeling of disparities in US breast cancer mortality

BACKGROUND

Populations of African American or Black women have persistently higher breast cancer mortality than the overall US population, despite having slightly lower age-adjusted incidence.

METHODS

Three Cancer Intervention and Surveillance Modeling Network simulation teams modeled cancer mortality disparities between Black female populations and the overall US population. Model inputs used racial group-specific data from clinical trials, national registries, nationally representative surveys, and observational studies. Analyses began with cancer mortality in the overall population and sequentially replaced parameters for Black populations to quantify the percentage of modeled breast cancer morality disparities attributable to differences in demographics, incidence, access to screening and treatment, and variation in tumor biology and response to therapy.

RESULTS

Results were similar across the 3 models. In 2019, racial differences in incidence and competing mortality accounted for a net ‒1% of mortality disparities, while tumor subtype and stage distributions accounted for a mean of 20% (range across models = 13%-24%), and screening accounted for a mean of 3% (range = 3%-4%) of the modeled mortality disparities. Treatment parameters accounted for the majority of modeled mortality disparities: mean = 17% (range = 16%-19%) for treatment initiation and mean = 61% (range = 57%-63%) for real-world effectiveness.

CONCLUSION

Our model results suggest that changes in policies that target improvements in treatment access could increase breast cancer equity. The findings also highlight that efforts must extend beyond policies targeting equity in treatment initiation to include high-quality treatment completion. This research will facilitate future modeling to test the effects of different specific policy changes on mortality disparities.

A Prospective Population-Based Study of Cardiovascular Disease Mortality following Treatment for Breast Cancer among Men in the United States, 2000-2019

Male breast cancer is rare but its incidence and mortality are increasing in the United States, with racial/ethnic disparities in survival reported. There is limited evidence for cardiotoxicity of cancer treatment among men with breast cancer. We evaluated the relation between breast cancer treatment and cardiovascular disease (CVD) mortality among men and investigated the salient roles that race/ethnicity play on this relation. Data were from 5216 men with breast cancer aged ≥ 40 years from the Surveillance, Epidemiology, and End Results program who were diagnosed from 2000 to 2019 and underwent surgery. Competing risk models were used to estimate hazards ratios (HR) and 95% confidence intervals (CI). During a median follow-up of 5.6 years, 1914 deaths occurred with 25% attributable to CVD. In multivariable-adjusted models, men who received chemotherapy had elevated risk for CVD (HR: 1.55, 95%CI: 1.18-2.04). This risk was higher among Hispanic men (HR: 3.96, 95%CI: 1.31-12.02) than non-Hispanic Black and non-Hispanic White men. There was no significant association between radiotherapy and CVD deaths. In this population-based study, treatment with chemotherapy was associated with elevated risk of CVD mortality in men with breast cancer. Racial/ethnic disparities in the association of chemotherapy and CVD mortality were observed.

Annual report to the nation on the status of cancer, part 1: National cancer statistics

BACKGROUND

The American Cancer Society, the Centers for Disease Control and Prevention, the National Cancer Institute, and the North American Association of Central Cancer Registries collaborate to provide annual updates on cancer occurrence and trends in the United States.

METHODS

Data on new cancer diagnoses during 2001-2018 were obtained from the North American Association of Central Cancer Registries' Cancer in North America Incidence file, which is comprised of data from Centers for Disease Control and Prevention-funded and National Cancer Institute-funded, population-based cancer registry programs. Data on cancer deaths during 2001-2019 were obtained from the National Center for Health Statistics' National Vital Statistics System. Five-year average incidence and death rates along with trends for all cancers combined and for the leading cancer types are reported by sex, racial/ethnic group, and age.

RESULTS

Overall cancer incidence rates were 497 per 100,000 among males (ranging from 306 among Asian/Pacific Islander males to 544 among Black males) and 431 per 100,000 among females (ranging from 309 among Asian/Pacific Islander females to 473 among American Indian/Alaska Native females) during 2014-2018. The trend during the corresponding period was stable among males and increased 0.2% on average per year among females, with differing trends by sex, racial/ethnic group, and cancer type. Among males, incidence rates increased for three cancers (including pancreas and kidney), were stable for seven cancers (including prostate), and decreased for eight (including lung and larynx) of the 18 most common cancers considered in this analysis. Among females, incidence rates increased for seven cancers (including melanoma, liver, and breast), were stable for four cancers (including uterus), and decreased for seven (including thyroid and ovary) of the 18 most common cancers. Overall cancer death rates decreased by 2.3% per year among males and by 1.9% per year among females during 2015-2019, with the sex-specific declining trend reflected in every major racial/ethnic group. During 2015-2019, death rates decreased for 11 of the 19 most common cancers among males and for 14 of the 20 most common cancers among females, with the steepest declines (>4% per year) reported for lung cancer and melanoma. Five-year survival for adenocarcinoma and neuroendocrine pancreatic cancer improved between 2001 and 2018; however, overall incidence (2001-2018) and mortality (2001-2019) continued to increase for this site. Among children (younger than 15 years), recent trends were stable for incidence and decreased for mortality; and among, adolescents and young adults (aged 15-39 years), recent trends increased for incidence and declined for mortality.

CONCLUSIONS

Cancer death rates continued to decline overall, for children, and for adolescents and young adults, and treatment advances have led to accelerated declines in death rates for several sites, such as lung and melanoma. The increases in incidence rates for several common cancers in part reflect changes in risk factors, screening test use, and diagnostic practice. Racial/ethnic differences exist in cancer incidence and mortality, highlighting the need to understand and address inequities. Population-based incidence and mortality data inform prevention, early detection, and treatment efforts to help reduce the cancer burden in the United States.

Evaluation of Racial/Ethnic Differences in Treatment and Mortality Among Women With Triple-Negative Breast Cancer

Importance

To our knowledge, there is no consensus regarding differences in treatment and mortality between non-Hispanic African American and non-Hispanic White women with triple-negative breast cancer (TNBC). Little is known about whether racial disparities vary by sociodemographic, clinical, and neighborhood factors.

Objective

To examine the differences in clinical treatment and outcomes between African American and White women in a nationally representative cohort of patients with TNBC and further examine the contributions of sociodemographic, clinical, and neighborhood factors to TNBC outcome disparities.

Design, Setting, and Participants

This population-based, retrospective cohort study included 23 123 women who received a diagnosis of nonmetastatic TNBC between January 1, 2010, and December 31, 2015, followed up through December 31, 2016, and identified from the Surveillance, Epidemiology, and End Results data set. The study was conducted from July 2019 to November 2020. The analyses were performed from July 2019 to June 2020.

Exposures

Race and ethnicity, including non-Hispanic African American and non-Hispanic White race.

Main Outcomes and Measures

Using logistic regression analysis and competing risk regression analysis, we estimated odds ratios (ORs) of receipt of treatment and hazard ratios (HRs) of breast cancer mortality in African American patients compared with White patients.

Results

Of 23 213 participants, 5881 (25.3%) were African American women and 17 332 (74.7%) were White women. Compared with White patients, African American patients had lower odds of receiving surgery (OR, 0.69; 95% CI, 0.60-0.79) and chemotherapy (OR, 0.89; 95% CI, 0.81-0.99) after adjustment for sociodemographic, clinicopathologic, and county-level factors. During a 43-month follow-up, 3276 patients (14.2%) died of breast cancer. The HR of breast cancer mortality was 1.28 (95% CI, 1.18-1.38) for African American individuals after adjustment for sociodemographic and county-level factors. Further adjustment for clinicopathological and treatment factors reduced the HR to 1.16 (95% CI, 1.06-1.25). This association was observed in patients living in socioeconomically less deprived counties (HR, 1.26; 95% CI, 1.14-1.39), urban patients (HR, 1.21; 95% CI, 1.11-1.32), patients having stage II (HR, 1.19; 95% CI, 1.02-1.39) or III (HR, 1.15; 95% CI, 1.01-1.31) tumors that were treated with chemotherapy, and patients younger than 65 years (HR, 1.24; 95% CI, 1.12-1.37).

Conclusions and Relevance

In this retrospective cohort study, African American women with nonmetastatic TNBC had a significantly higher risk of breast cancer mortality compared with their White counterparts, which was partially explained by their disparities in receipt of surgery and chemotherapy.

Protocol for Symptom Experience, Management, Outcomes, and Adherence in Women Receiving Breast Cancer Chemotherapy

BACKGROUND

The 5-year survival for Black women with breast cancer in the United States is lower than White women for stage-matched disease. Our past and ongoing work and that of others suggest that symptom incidence, cancer-related distress, and ineffective communication contribute to racial disparity in dose reduction and early therapy termination. Although race is perhaps the most studied social determinant of health, it is clear that race alone does not account for all disparities.

OBJECTIVES

The aim of the study was to present a study protocol of Black and White women prescribed breast cancer chemotherapy. The aims are to (1) examine and compare chemotherapy received/prescribed over time and in total; (2a) examine and compare symptom incidence, distress, and management and clinical encounter, including patient-centeredness of care and management experience over time and (2b) correlate symptom incidence, distress, and management experience to Aim 1; and (3) explore the effects of social determinants of health, including age, income, education, zip code, and lifetime stress exposure, on Aims 1, 2a, and 2b.

METHODS

A longitudinal, repeated-measures (up to 18 time points), comparative, mixed-methods design is employed with 179 White and 179 Black women from 10 sites in Western Pennsylvania and Northeast Ohio over the course of chemotherapy and for 2 years following completion of therapy.

RESULTS

The study began in January 2018, with estimated complete data collection by late 2023.

DISCUSSION

This study is among the first to explore the mechanistic process for racial disparity in dosage and delay across the breast cancer chemotherapy course. It will be an important contribution to the explanatory model for breast cancer treatment disparity and may advance potential mitigation strategies for racial survival disparity.