Influence of provider factors and race on uptake of breast cancer gene expression profiling

Catchment area and cancer population health research through a novel population-based statewide database: a scoping review

BACKGROUND

Population-based linked datasets are vital to generate catchment area and population health research. The novel Cancer Information and Population Health Resource (CIPHR) links statewide cancer registry data, public and private insurance claims, and provider- and area-level data, representing more than 80% of North Carolina's large, diverse population of individuals diagnosed with cancer. This scoping review of articles that used CIPHR data characterizes the breadth of research generated and identifies further opportunities for population-based health research.

METHODS

Articles published between January 2012 and August 2023 were categorized by cancer site and outcomes examined across the care continuum. Statistically significant associations between patient-, provider-, system-, and policy-level factors and outcomes were summarized.

RESULTS

Among 51 articles, 42 reported results across 23 unique cancer sites and 13 aggregated across multiple sites. The most common outcomes examined were treatment initiation and/or adherence (n = 14), mortality or survival (n = 9), and health-care resource utilization (n = 9). Few articles focused on cancer recurrence (n = 1) or distance to care (n = 1) as outcomes. Many articles discussed racial, ethnic, geographic, and socioeconomic inequities in care.

CONCLUSIONS

These findings demonstrate the value of robust, longitudinal, linked, population-based databases to facilitate catchment area and population health research aimed at elucidating cancer risk factors, outcomes, care delivery trends, and inequities that warrant intervention and policy attention. Lessons learned from years of analytics using CIPHR highlight opportunities to explore less frequently studied cancers and outcomes, motivate equity-focused interventions, and inform development of similar resources.

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.

From Race to Racism and Disparities to Equity: An Actionable Biopsychosocial Approach to Breast Cancer Outcomes

PURPOSE

Racial disparities in outcomes of breast cancer in the United States have widened over more than 3 decades, driven by complex biologic and social factors. In this review, we summarize the biological and social narratives that have shaped breast cancer disparities research across different scientific disciplines in the past, explore the underappreciated but crucial ways in which these 2 strands of the breast cancer story are interwoven, and present 5 key strategies for creating transformative interdisciplinary research to achieve equity in breast cancer treatment and outcomes.

DESIGN

We first review the key differences in tumor biology in the United States between patients racialized as Black versus White, including the overrepresentation of triple-negative breast cancer and differences in tumor histologic and molecular features by race for hormone-sensitive disease. We then summarize key social factors at the interpersonal, institutional, and social structural levels that drive inequitable treatment. Next, we explore how biologic and social determinants are interwoven and interactive, including historical and contemporary structural factors that shape the overrepresentation of triple-negative breast cancer among Black Americans, racial differences in tumor microenvironment, and the complex interplay of biologic and social drivers of difference in outcomes of hormone receptor positive disease, including utilization and effectiveness of endocrine therapies and the role of obesity. Finally, we present 5 principles to increase the impact and productivity of breast cancer equity research.

RESULTS

We find that social and biologic drivers of breast cancer disparities are often cyclical and are found at all levels of scientific investigation from cells to society. To break the cycle and effect change, we must acknowledge and measure the role of structural racism in breast cancer outcomes; frame biologic, psychosocial, and access factors as interwoven via mechanisms of cumulative stress, inflammation, and immune modulation; take responsibility for the impact of representativeness (or the lack thereof) in genomic and decision modeling on the ability to accurately predict the outcomes of Black patients; create research that incorporates the perspectives of people of color from inception to implementation; and rigorously evaluate innovations in equitable cancer care delivery and health policies.

CONCLUSIONS

Innovative, cross-disciplinary research across the biologic and social sciences is crucial to understanding and eliminating disparities in breast cancer outcomes.

Understanding Racial and Ethnic Inequities in Uptake and Outcomes Following Multigene Prognostic Testing in Early Breast Cancer: The Promise of Real-World Data

In the past decades, multigene prognostic testing, such as Oncotype DX (ODX), has been increasingly used to inform treatment decisions for patients with early-stage breast cancer. This advance in precision oncology has increased existing concerns about differential access to genomic testing across racial and ethnic groups. The investigation by Moore and colleagues, analyzing real-world data from the National Cancer Database, shows that patients of color with breast cancer were less likely to receive ODX testing and Black patients were more likely to have a high risk Recurrence Score (RS) compared with White patients. This study emphasizes that the appropriate adoption of ODX testing is critical to promote equitable cancer care for patients with breast cancer. The reported associations on overall survival across specific racial and ethnic groups provided here give additional insight to the known associations between the ODX RS and outcomes of distant recurrence and cancer-specific mortality. Analyses of contemporary, real-world data from diverse populations with long-term follow-up should continue to keep pace with the expansion of precision breast cancer care to better understand and mitigate potentially widening inequities in genomic testing. See related article by Moore et al., p. 821.

Oncotype DX Risk Recurrence Score and Total Mortality for Early-Stage Breast Cancer by Race/Ethnicity

BACKGROUND

Oncotype DX recurrence score (ODX RS) is a prognostic biomarker for early-stage, node-negative, estrogen receptor-positive (ER+) breast cancer. Whether test uptake, associated factors, and the test's prognostic values differ by race/ethnicity is unknown.

METHODS

From the National Cancer Database, 2010-2014, we identified 227,259 early-stage ER+, node-negative breast cancer cases. Logistic regression was used to examine ODX RS uptake and associated factors among non-Hispanic White (White), non-Hispanic Black (Black), Hispanic, and Asian American patients. Cox regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for overall mortality with ODX RS by race/ethnicity.

RESULTS

White patients were more likely to receive an ODX RS test compared with Black, Hispanic, and Asian American patients (36.7%, 32.8%, 31.6%, and 35.5%, respectively; P < 0.001). Disparities persisted after adjustments for demographics, clinical characteristics, and access-to-care, with rate ratios of 0.87 (95% CI, 0.85-0.88), 0.82 (95% CI, 0.80-0.85), and 0.89 (95% CI, 0.87-0.92), respectively, for Black, Hispanic, and Asian American compared with White patients. Black patients had higher proportions of high-risk scores (≥26) compared with White, Hispanic, and Asian American patients (19.1%, 14.0%, 14.2%, and 15.6%, respectively; P < 0.0001). ODX RS was predictive for total mortality across all races/ethnicities, particularly younger patients (<50). No significant race/ethnicity interactions were observed.

CONCLUSIONS

Although ODX RS uptake and risk distribution varied by race/ethnicity, ODX RS was prognostic for mortality across groups.

IMPACT

These findings emphasize the importance of developing strategies to increase ODX RS uptake among racial/ethnic minorities and call for more investigations on potential racial/ethnic differences in breast cancer biology. See related commentary by Wang et al., p. 704.

Adherence to Endocrine Therapy and Racial Outcome Disparities in Breast Cancer

The disparity in outcomes of breast cancer for Black compared with White women in the U.S. is well known and persistent over time, with the largest disparities appearing among women with hormone receptor-positive (HR+) cancers. The racial gap in breast cancer survival first emerged in the 1980s, a time of significantmen treatment advances in early-stage breast cancer, including the introduction of adjuvant endocrine therapy. Since that time, the gap has continued to widen despite steady advances in treatment and survival of breast cancer overall. Although advanced stage at presentation and unfavorable biology undoubtedly contribute to racial differences in survival of HR+ breast, treatment disparities are increasingly acknowledged to play a key role as well. The recent recognition of racial differences in endocrine therapy use may be a key explanatory factor in the persistent racial gap in mortality of HR+ disease, and may be a key focus of intervention to improve breast cancer outcomes for Black women. IMPLICATIONS FOR PRACTICE: Black women with hormone receptor-positive breast cancer experience the greatest racial disparity in survival among all breast cancer subtypes. This survival gap appears consistently across studies and is not entirely explained by differences in presenting stage, tumor biology as assessed by genomic risk scores, or receipt of chemotherapy. Recent research highlights lower adherence to endocrine therapy (ET) for Black women. Health systems and individual providers should focus on improving communication about the importance of ET use, sharing decisions around ET, providing appropriate support for side effects and other ET-related concerns, and equitably delivering survivorship care, including ET adherence assessment.

Race and delays in breast cancer treatment across the care continuum in the Carolina Breast Cancer Study

BACKGROUND

After controlling for baseline disease factors, researchers have found that black women have worse breast cancer survival, and this suggests that treatment differences may contribute to poorer outcomes. Delays in initiating and completing treatment are one proposed mechanism.

METHODS

Phase 3 of the Carolina Breast Cancer Study involved a large, population-based cohort of women with incident breast cancer. For this analysis, we included black women (n = 1328) and white women (n = 1331) with stage I to III disease whose treatment included surgery with or without adjuvant therapies. A novel treatment pathway grouping was used to benchmark the treatment duration (surgery only, surgery plus chemotherapy, surgery plus radiation, or all 3). Models controlled for the treatment pathway, age, and tumor characteristics and for demographic factors related to health care access. Exploratory analyses of the association between delays and cancer recurrence were performed.

RESULTS

In fully adjusted analyses, blacks had 1.73 times higher odds of treatment initiation more than 60 days after their diagnosis in comparison with whites (odds ratio [OR], 1.73; 95% confidence interval [CI], 1.04-2.90). Black race was also associated with a longer treatment duration. Blacks were also more likely to be in the highest quartile of treatment duration (OR, 1.69; 95% CI, 1.41-2.02), even after adjustments for demographic and tumor characteristics (OR, 1.31; 95% CI, 1.04-1.64). A nonsignificant trend toward a higher recurrence risk was observed for patients with delayed initiation (hazard ratio, 1.44; 95% CI, 0.89-2.33) or the longest duration (hazard ratio, 1.17; 95% CI, 0.87-1.59).

CONCLUSIONS

Black women more often had delayed treatment initiation and a longer duration than whites receiving similar treatment. Interventions that target access barriers may be needed to improve timely delivery of care.

Uptake of the 21-Gene Assay Among Women With Node-Positive, Hormone Receptor−Positive Breast Cancer

Background: This study assessed uptake of the Oncotype DX 21-gene assay over time and characterized which sociodemographic and clinical factors are associated with test uptake among women with lymph node−positive (LN+), hormone receptor−positive, HER2-negative breast cancer. Methods: Invasive breast cancer cases diagnosed in 2010 through 2013 were included from a SEER database linked to 21-gene assay results performed at Genomic Health’s Clinical Laboratory. Factors associated with 21-gene assay uptake were identified using a multivariable logistic regression model. Results: Uptake of the 21-gene assay increased over time and differed by race, socioeconomic status (SES), and age. In the multivariable model, when clinical and SES variables were controlled for, racial differences in test uptake were no longer observed. Private insurance status was associated with higher odds of 21-gene assay uptake (Medicaid vs private insurance: adjusted odds ratio, 0.86; P=.02), and high area-level SES was associated with an increased odds of uptake (quintile 5 vs 1: adjusted odds ratio, 1.6; P<.001). Demographic factors such as age and marital status influenced test uptake, and use varied greatly by geographic region. Uptake of the 21-gene assay increased over time and preceded the assay’s inclusion in the NCCN Guidelines for LN+ breast cancer. Differences in uptake by race, SES, and age have persisted over time. However, when clinical and SES variables were controlled for, racial differences in assay uptake were no longer observed. Socioeconomic variables, such as health insurance type and area-level SES, were associated with assay uptake. Conclusions: Future research should continue to document practice patterns related to the 21-gene assay. Given variation in testing associated with area-level SES, insurance coverage, and geographic region, interventions to understand and reduce differential uptake are needed to ensure equitable access to this genomic test.