Disparities In Breast Cancer Mortality Research Articles

Socioecologic Factors and Racial Differences in Breast Cancer Multigene Prognostic Scores in US Women

Disproportionately aggressive tumor biology among non-Hispanic Black women with early-stage, estrogen receptor (ER)-positive breast cancer contributes to racial disparities in breast cancer mortality. It is unclear whether socioecologic factors underlie racial differences in breast tumor biology. To examine individual-level (insurance status) and contextual (area-level socioeconomic position and rural or urban residence) factors as possible mediators of racial and ethnic differences in the prevalence of ER-positive breast tumors with aggressive biology, as indicated by a high-risk gene expression profile. This retrospective cohort study included women 18 years or older diagnosed with stage I to II, ER-positive breast cancer between January 1, 2007, and December 31, 2015. All data analyses were conducted between December 2022 and April 2023. The primary outcome was the likelihood of a high-risk recurrence score (RS) (≥26) on the Oncotype DX 21-gene breast tumor prognostic genomic biomarker. Among 69 139 women (mean [SD] age, 57.7 [10.5] years; 6310 Hispanic [9.1%], 274 non-Hispanic American Indian and Alaskan Native [0.4%], 6017 non-Hispanic Asian and Pacific Islander [8.7%], 5380 non-Hispanic Black [7.8%], and 51 158 non-Hispanic White [74.0%]) included in our analysis, non-Hispanic Black (odds ratio [OR], 1.33; 95% CI, 1.23-1.43) and non-Hispanic American Indian and Alaska Native women (OR, 1.38; 95% CI, 1.01-1.86) had greater likelihood of a high-risk RS compared with non-Hispanic White women. There were no significant differences among other racial and ethnic groups. Compared with non-Hispanic White patients, there were greater odds of a high-risk RS for non-Hispanic Black women residing in urban areas (OR, 1.35; 95% CI, 1.24-1.46), but not among rural residents (OR, 1.05; 95% CI, 0.77-1.41). Mediation analysis demonstrated that lack of insurance, county-level disadvantage, and urban vs rural residence partially explained the greater odds of a high-risk RS among non-Hispanic Black women (proportion mediated, 17%; P < .001). The findings of this cohort study suggest that the consequences of structural racism extend beyond inequities in health care to drive disparities in breast cancer outcome. Additional research is needed with more comprehensive social and environmental measures to better understand the influence of social determinants on aggressive ER-positive tumor biology among racial and ethnic minoritized women from disadvantaged and historically marginalized communities.

A Novel Approach for Conducting a Catchment Area Analysis of Breast Cancer by Age and Stage for a Community Cancer Center.

The U.S. Preventive Services Task Force recently issued an updated draft recommendation statement to initiate breast cancer screening at age 40, reflecting well-documented disparities in breast cancer-related mortality that disproportionately impact younger Black women. This study applied a novel approach to identify hotspots of breast cancer diagnosed before age 50 and/or at an advanced stage to improve breast cancer detection within these communities. Cancer registry data for 3,497 women with invasive breast cancer diagnosed or treated between 2012 and 2020 at the Helen F. Graham Cancer Center and Research Institute (HFGCCRI) and who resided in the HFGCCRI catchment area, defined as New Castle County, Delaware, were geocoded and analyzed with spatial intensity. Standardized incidence ratios stratified by age and race were calculated for each hotspot. Four hotspots were identified, two for breast cancer diagnosed before age 50, one for advanced breast cancer, and one for advanced breast cancer diagnosed before age 50. Younger Black women were overrepresented in these hotspots relative to the full-catchment area. The novel use of spatial methods to analyze a community cancer center catchment area identified geographic areas with higher rates of breast cancer with poor prognostic factors and evidence that these areas made an outsized contribution to racial disparities in breast cancer. Identifying and prioritizing hotspot breast cancer communities for community outreach and engagement activities designed to improve breast cancer detection have the potential to reduce the overall burden of breast cancer and narrow racial disparities in breast cancer.

Breast cancer mortality among ultra-orthodox and non-ultra-orthodox Israeli women: A retrospective cohort study

BackgroundBreast cancer is the leading cause of cancer death in Israeli women. Previous studies found socioeconomic status and other risk factors impact breast cancer outcomes. The ultra-orthodox community is characterized by a longer life expectancy, lower rates of mammography performance, higher fertility rates and other sociodemographic variables that may be related to breast cancer mortality. This study examined disparities in breast cancer mortality between ultra-Orthodox and non-ultra-Orthodox Israeli women. MethodsThis retrospective cohort study for breast cancer mortality included the all Jewish Israeli citizens women born between 1940 and 1960 and lived in communities with over 20,000 residents (n = 628,617). Data was collected from various sources, monitoring a period of 31 years; for each participants, their sociodemographic characteristics were compiled from the population registry, the tax authority, the education registry, and the Central Bureau of Statistics (CBS). Variables included religiosity, age, marital status, children, origin, education, and income. Multivariable Cox models evaluated predictors of mortality. ResultsOf the 628,617 women in the study, 29,611 were ultra-Orthodox. Ultra-Orthodox women had higher marriage rates, more children, and lower secular education and income. Mortality was 108.8/100,000 overall, lower among ultra-Orthodox (83.4/100,000) than non-ultra-Orthodox women (110.1/100,000) despite their risk factors. Using a multivariate model to evaluate the association between ultra-Orthodoxy and breast cancer mortality, the study found higher breast cancer mortality rate among non-ultra-Orthodox women compared to ultra-Orthodox women (HR = 1.491; 99% CI = 1.232, 1.804). Associations with sociodemographic variables were different for each group. ConclusionsAlthough ultra-Orthodox women have socioeconomic risk factors, breast cancer mortality was lower than non-ultra-Orthodox women. Further research on potential cultural and religious factors influencing mortality is warranted. These findings highlight the importance of evaluating predictors within specific populations.

Abstract C118: Racial disparities in insurance coverage for supplemental breast cancer screening

Abstract Introduction and Purpose: Women with dense breasts have increased risk both for developing breast cancer and false-negative mammograms. Supplemental screening with breast MRI has been shown to shown to significantly increase cancer detection among women with dense breasts. In May 2023, Pennsylvania (PA) mandated insurance coverage of one supplemental screening study (breast MRI or ultrasound ) annually for women with dense breasts. Prior research suggests that Black women have lower breast density on average than white women based on subjective grading from the American College of Radiology Breast Imaging and Reporting Data System (BI-RADS), partially due to larger average breast size and higher body mass index (BMI) than white women. The purpose of this study was to estimate the potential impact of this supplemental screening law on different patient populations in a large health system. Methods: Women without prior breast cancer or known BRCA1/2 mutations who underwent mammographic screening at a large PA health system from April 2015-December 2017and completed a risk factor questionnaire were included (N=83,579). Under PA law, women must have either heterogeneously dense breasts plus &amp;gt;20% lifetime risk of breast cancer or extremely dense breasts to be eligible for insurance coverage for supplemental screening, both of which involve subjectively graded breast measurements. Breast cancer risk for each patient was estimated using the Gail model. The cancer detection rate (CDR) for mammographic screening was calculated as the number of cancers diagnosed within one year of a positive mammographic screen; the interval cancer rate was calculated as the number of cancers diagnosed within one year of a non-actionable screening mammogram per 1000 women. Logistic regression was used to calculate the odds of eligibility adjusted for age and BMI. Results: Black women were less likely to have extremely or heterogeneously dense breasts than white women (23.7% vs. 45.0%, p&amp;lt;0.001). Under PA law, 2.5% of Black women and 9.9% of white women would qualify for insurance coverage for supplemental screening (p&amp;lt;0.001). Only 0.2% of Black women and 2.3% of white women had heterogeneously dense breasts and &amp;gt;20% lifetime risk. Black women were more likely to have triple-negative breast cancer (TNBC) than white women (p&amp;lt;0.001). After adjusting for age and BMI, Black women remained 54% less likely to be eligible for supplemental screening than white women (OR=0.46, 95% 0.42-0.51, p&amp;lt;0.001).Conclusions: Black women are less likely to qualify for insurance coverage for supplemental breast cancer screening than white women under PA law. Given that Black women have lower prevalence of subjectively graded dense breasts and higher prevalence of TNBC, the new supplemental screening law is unlikely to meaningfully reduce racial disparities in breast cancer mortality. Methods to better assess breast cancer risk among Black women, particularly the risk of TNBC, are urgently needed to identify Black women that may benefit from supplemental screening. Citation Format: Mattia A. Mahmoud, Sarah Ehsan, Oluwadamilola M. Fayanju, Susan M. Domchek, Katherine L. Nathanson, Despina Kontos, Emily F. Conant, Anne Marie McCarthy. Racial disparities in insurance coverage for supplemental breast cancer screening [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr C118.

A catchment and location-allocation analysis of mammography access in Delaware, US: implications for disparities in geographic access to breast cancer screening

BackgroundDespite a 40% reduction in breast cancer mortality over the last 30 years, not all groups have benefited equally from these gains. A consistent link between later stage of diagnosis and disparities in breast cancer mortality has been observed by race, socioeconomic status, and rurality. Therefore, ensuring equitable geographic access to screening mammography represents an important priority for reducing breast cancer disparities. Access to breast cancer screening was evaluated in Delaware, a state that experiences an elevated burden from breast cancer but is otherwise representative of the US in terms of race and urban–rural characteristics. We first conducted a catchment analysis of mammography facilities. Finding evidence of disparities by race and rurality, we next conducted a location-allocation analysis to identify candidate locations for the establishment of new mammography facilities to optimize equitable access.MethodsA catchment analysis using the ArcGIS Pro Service Area analytic tool characterized the geographic distribution of mammography sites and Breast Imaging Centers of Excellence (BICOEs). Poisson regression analyses identified census tract-level correlates of access. Next, the ArcGIS Pro Location-Allocation analytic tool identified candidate locations for the placement of additional mammography sites in Delaware according to several sets of breast cancer screening guidelines.ResultsThe catchment analysis showed that for each standard deviation increase in the number of Black women in a census tract, there were 68% (95% CI 38–85%) fewer mammography units and 89% (95% CI 60–98%) fewer BICOEs. The more rural counties in the state accounted for 41% of the population but only 22% of the BICOEs. The results of the location-allocation analysis depended on which set of screening guidelines were adopted, which included increasing mammography sites in communities with a greater proportion of younger Black women and in rural areas.ConclusionsThe results of this study illustrate how catchment and location-allocation analytic tools can be leveraged to guide the equitable selection of new mammography facility locations as part of a larger strategy to close breast cancer disparities.

Enhancing Mammography and Empowering Solutions for Breast Cancer Disparities.

Mammography enables early detection of breast cancer, a critical factor in improving treatment outcomes and breast cancer mortality. Yet, not all women benefit equally, and striking racial disparities in breast cancer mortality persist, with Black women 40% more likely to die from breast cancer compared with non-Hispanic White women. The current issue of Cancer Epidemiology, Biomarkers & Prevention presents three informative reports revealing racial and ethnic variations in mammography's performance in risk stratification, detection, and surveillance. The performance dynamics of mammography across different racial and ethnic groups highlight the urgency for additional research and innovative interventions to ensure equitable breast cancer control. We emphasize a pressing need for a comprehensive evaluation of multilevel influences on the performance and implementation of mammography in racially and ethnically diverse populations, complemented by equally urgent efforts to address factors influencing the risk of aggressive tumor subtypes and timely and effective treatment delivery. See related articles by Kerlikowske et al., p. 1524, Hubbard et al., p. 1531, Nyante et al., p. 1542.

Considerations in Narrowing the Breast Cancer Mortality Gap Between Black and White Women

This Viewpoint discusses 3 key measures of population-based surveillance along with areas for future investigation to reduce racial disparities in breast cancer mortality.

Effects of social comparison framing of racial health disparities and behaviors

Abstract Messages that feature intergroup comparisons (social comparison frames) regularly communicate the relative prevalence of health problems and preventive behaviors. While prior studies find that comparing disease risks between racial groups are met with resistance from the disadvantaged group, we extended existing research by investigating if behavioral comparisons which show that the higher-risk group also excels in disease prevention efforts could mitigate negative impacts of disease risk comparisons. We conducted two preregistered experiments to examine the effects of comparing cancer risks and the prevalence of screening behaviors between Black and White Americans. Communicating racial disparities in breast cancer mortality reduced perceived risks and fear among White Americans (the less-at-risk group) and decreased cancer screening intention among Black Americans (the disadvantaged group). Adding cancer screening prevalence comparisons did not shift screening intentions among Black Americans but changed their support for disparity-reducing policies, though the effects depended on the disease in question.

Breast health equity along the cancer care continuum: Acollaborative grant initiative.

A competitive grants program developed by the American Cancer Society and Pfizer Global Medical Grants funded nine community‐engaged projects with innovative interventions aimed at reducing breast cancer mortality disparities between Black and White women. This introduction details the purpose and scope of this program and addresses the potential of community‐driven projects along the cancer care continuum.

Disparities in breast cancer mortality among Latin American women: trends and predictions for 2030

BackgroundBreast cancer is among the leading cause of cancer-related mortality among Latin American and Caribbean (LAC) women, but a comprehensive and updated analysis of mortality trends is lacking. The objective of this study was to determine the breast cancer mortality rates between 1997 and 2017 for LAC countries and predict mortality until 2030.MethodsWe retrieved breast cancer deaths across 17 LAC countries from the World Health Organization mortality database. Age-standardized mortality rates per 100,000 women-years were estimated. Mortality trends were evaluated with Joinpoint regression analyses by country and age group (all ages, < 50 years, and ≥ 50 years). By 2030, we predict number of deaths, mortality rates, changes in population structure and size, and the risk of death from breast cancer.ResultsArgentina, Uruguay, and Venezuela reported the highest mortality rates throughout the study period. Guatemala, El Salvador, and Nicaragua reported the largest increases (from 2.4 to 2.8% annually), whereas Argentina, Chile, and Uruguay reported downward trends (from − 1.0 to − 1.6% annually). In women < 50y, six countries presented downward trends and five countries showed increasing trends. In women ≥ 50y, three countries had decreased trends and ten showed increased trends. In 2030, increases in mortality are expected in the LAC region, mainly in Guatemala (+ 63.0%), Nicaragua (+ 47.3), El Salvador (+ 46.2%), Ecuador (+ 38.5%) and Venezuela (+ 29.9%).ConclusionOur findings suggest considerable differences in breast cancer mortality across LAC countries by age group. To achieve the 2030 sustainable developmental goals, LAC countries should implement public health strategies to reduce mortality by breast cancer.

Mobile Web App Intervention to Promote Breast Cancer Screening Among American Indian Women in the Northern Plains: Feasibility and Efficacy Study.

Breast cancer is the most common cancer in the United States and the second leading cause of death for American Indian women. American Indian women have lower rates of breast cancer screening than other racial groups, and disparities in breast cancer mortality and survival rates persist among them. To address this critical need, a culturally appropriate, accessible, and personalized intervention is necessary to promote breast cancer screening among American Indian women. This study used mobile health principles to develop a mobile web app-based mammogram intervention (wMammogram) for American Indian women in a remote, rural community in the Northern Plains. This study aimed to assess the feasibility and efficacy of the wMammogram intervention, which was designed to motivate American Indian women to undergo breast cancer screening, as compared with the control group, who received an educational brochure. Using community-based participatory research (CBPR) principles and a multipronged recruitment strategy in a randomized controlled trial design, we developed the wMammogram intervention. This study involved 122 American Indian women aged between 40 and 70 years, who were randomly assigned to either the intervention group (n=62) or the control group (n=60). Those in the intervention group received personalized and culturally appropriate messages through a mobile web app, while those in the control group received an educational brochure. We measured outcomes such as mammogram receipt, intention to receive breast cancer screening after the intervention, and participants' satisfaction with and acceptance of the intervention. A significantly higher proportion of women who received the wMammogram intervention (26/62, 42%; P=.009) completed mammograms by the 6-month follow-up than the control group (12/60, 20%). The wMammogram intervention group, compared with the control group, reported significantly higher ratings on perceived effectiveness of the intervention (t120=-5.22; P<.001), increase in knowledge (t120=-4.75; P<.001), and satisfaction with the intervention (t120=-3.61; P<.001). Moreover, compared with the brochure group, the intervention group expressed greater intention to receive a mammogram in the future when it is due (62/62, 100% vs 51/60, 85%) and were more willing to recommend the intervention they received to their friends (61/62, 98.4% vs 54/60, 90%) with statistically significant differences. This study shows the feasibility and efficacy of the wMammogram intervention to promote breast cancer screening for American Indian women in a remote, rural community-based setting. Findings suggest that, with advancements in technology and the ubiquity of mobile devices, mobile web apps could serve as a valuable health intervention tool that builds upon low-cost technology and enhances accessibility and sustainability of preventive care to help reduce breast health disparities experienced in hard-to-reach American Indian populations. ClinicalTrials.gov NCT05530603; https://clinicaltrials.gov/ct2/show/NCT05530603.

Increasing Clinical Trial Participation of Black Women Diagnosed with Breast Cancer

Despite racial disparities in breast cancer mortality, Black women remain underrepresented in clinical trials. In this mixed methods research, 48 Black women were engaged via focus group discussions and in-depth interviews to better understand the lived experience of women with breast cancer. The results of this qualitative study informed the development of a subsequent online survey to identify barriers, motivators, and other factors that influence decision-making by Black women diagnosed with breast cancer when considering clinical trial participation. Among the 257 Black survey participants, most (95%) were aware of clinical trials; of those, most viewed them as lifesaving (81%) and/or benefiting others (90%). Negative perceptions such as serious side effects (58%), not receiving real treatment (52%), or risk of potential harm (62%) were indicated. Barriers included financial expenses (49%), concerns that their condition could be made worse (29%), that they would receive a placebo (28%), or that treatment was unapproved (28%). Participants were more likely than their health care providers (HCPs) to initiate discussions of clinical trials (53% versus 33%), and 29% of participants indicated a need for more information about risks and benefits, even after having those conversations. The most trustworthy sources of information on clinical trials were HCPs (66%) and breast cancer support groups (64%). These results suggest that trusted communities are key for providing education on clinical trials. However, there is also a need for HCPs to proactively discuss clinical trials with patients to ensure that they are adequately informed about all aspects of participation.

Racial/ethnic and socioeconomic differences in breast cancer surgery performed and delayed surgical treatment: Mediating impact on mortality.

585 Background: Breast cancer is the most common malignancy affecting women of all racial and ethnic backgrounds in the United States (US). Although Socioeconomic status (SES), race/ethnicity, and surgical type/delays are associated with breast cancer mortality outcomes, studies on these associations have been contrasting. This study examined the racial/ethnic and SES differences in surgical treatment types and delays. Also, we quantified the extent to which these differences explained the racial/ethnic disparities in breast cancer mortality. Methods: We studied 290,066 women 40+ years old diagnosed with breast cancer between 2010 and 2017 identified from the Surveillance, Epidemiology, and End Results database. We performed logistic regression models to examine the association of SES and race/ethnicity with surgical treatment type and delays. We performed mediation analysis models to quantify the extent to which mortality differences were mediated by treatment, sociodemographic, and clinicopathologic factors. The study subjects were de-identified, and there was no patient contact; thus, the study was exempted from an Institutional Review Board's (IRB) approval. A p-value less than 0.05 indicated significant associations for the descriptive statistics, logistic and Cox proportional hazard regressions, and mediation analysis. We used Stata 17 to perform the analyses. Results: Non-Hispanic (NH) Black [Odds ratio (OR) = 1.16, 95% CI: 1.13-1.19] and Hispanic women [OR = 1.27, 95% CI: 1.24-1.31] were significantly more likely to undergo mastectomy compared to NH White women. Similarly, NH Black and Hispanic women had higher odds of delayed surgical treatment than NH Whites. Patients in the highest SES quintile, compared to those in lowest the lowest, were less likely to experience breast cancer-specific mortality (BCSM). Variations in treatment, SES, and clinicopathological factors significantly explained 70% of the excess BCSM among NH Blacks compared to their NH White counterparts. Conclusions: In conclusion, health disparity continues to be a major societal concern in the US. It affects people of all ages, socioeconomic classes, and ethnic/racial backgrounds. The findings of this study showed that racial and ethnic minorities, the majority of whom have a lower socioeconomic position, are significantly disadvantaged regarding the evaluation, quality, cost, and duration of medical care. Future studies can assess the multifactorial effects of sociodemographic factors like SES, access to health care assessment, and educational background amidst other variables as a multidimensional predictor of treatment delay and overall survival of breast cancer and other health issues among minoritized populations.

Disease outcomes by race in patients with high-risk triple negative breast cancer with residual disease after neoadjuvant chemotherapy: A post-hoc analysis of the EA1131 randomized clinical trial.

586 Background: Black women with breast cancer have the highest breast cancer mortality (BCM) rates of any racial and ethnic group. The higher burden of triple negative breast cancer (TNBC) in Black women contributes to disparities in BCM, but the extent to which disparate outcomes exist in patients with similar tumor biology is uncertain. The objective of this study was to examine racial differences in disease outcomes and BCM between Black and White patients in a clinical trial population of high-risk TNBC with residual disease after neoadjuvant chemotherapy (NAC). Methods: From 2015-2021, the ECOG-ACRIN EA1131 clinical trial randomized 415 clinical stage II-III TNBC patients with residual disease after NAC to either adjuvant capecitabine or platinum. For this analysis, 366 patients with known self-reported Black or White race and follow-up data were included. The aim of this unplanned exploratory analysis was to examine locoregional recurrence (LRR), distant recurrence (DR), and BCM by race using Kaplan-Meier curves for unadjusted estimates and Cox modeling for adjusted analyses. Results: Racial distribution of the analysis population included 66 (18.0%) Black and 300 (82.0%) White patients. 239 (65.3%) patients presented with clinical stage II and 127 (34.7%) with stage III disease. All patients had residual pathological disease after NAC: 86 (23.5%) stage I, 176 (48.1%) stage II, and 102 (27.9%) stage III (n=2 unknown). Median age was 49 years in Black and 54 years in White patients, p=0.003. Disease presentation, response to chemotherapy, and treatment arm were similar by race. Median follow up was 20 months. 2-year estimated LRR occurred in 31.6% of Black and 18.6% of White patients although this was not statistically significant (p=0.387), and 2-year estimated DR and BCM were similar by race. Estimated 2-year outcomes are outlined. Models adjusted for race, age, stage, grade, treatment arm, and locoregional therapy did not identify race as an independent predictor of LRR, DR, or BCM. Higher pathologic stage was the only consistent independent predictor of recurrent disease or BCM (stage III with HR 6.14 for LRR; HR 5.16 for DR; HR 6.84 for BCM; all p&lt;0.001). Conclusions: In this population of high-risk patients with residual TNBC after NAC with similar tumor biology treated on a clinical trial, there was a trend towards increased LRR in Black patients and similar DR and BCM between Black and White patients at 2 years of follow-up. This suggests that differences in BCM in other breast cancer populations may be at least partially driven by differences in tumor biology. Clinical trial information: NCT02445391 . [Table: see text]

274P Racial and ethnic disparities in breast cancer mortality in women with and without diabetes between 2005 and 2020

274P Racial and ethnic disparities in breast cancer mortality in women with and without diabetes between 2005 and 2020

Racial/ethnic and socioeconomic differences in breast cancer surgery performed and delayed treatment: mediating impact on mortality.

Although Socioeconomic status (SES), race/ethnicity, surgical type, and treatment delays are associated with breast cancer mortality outcomes, studies on these associations have been contrasting. This study examined the racial/ethnic and SES differences in surgical treatment types and treatment delays. Also, we quantified the extent to which these differences explained the racial/ethnic disparities in breast cancer mortality. We studied 290,066 women 40 + years old diagnosed with breast cancer between 2010 and 2017 identified from the Surveillance, Epidemiology, and End Results database. We performed logistic regression models to examine the association of SES and race/ethnicity with surgical treatment type and treatment delays. We performed mediation analysis models to quantify the extent to which mortality differences were mediated by treatment, sociodemographic, and clinicopathologic factors. Non-Hispanic (NH) Black [Odds ratio (OR) = 1.16, 95% CI 1.13-1.19] and Hispanic women [OR = 1.27, 95% CI 1.24-1.31] were significantly more likely to undergo mastectomy compared to NH White women. Similarly, NH Black and Hispanic women had higher odds of delayed treatment than NH Whites. Patients in the highest SES quintile, compared to those in lowest the lowest, were less likely to experience breast cancer-specific mortality (BCSM). Variations in treatment, SES, and clinicopathological factors significantly explained 70% of the excess BCSM among NH Blacks compared to their NH White counterparts. Bridging the gap of access to adequate healthcare services for all to diminish the disproportionate burden of breast cancer would require a multifactorial approach that addresses several biological and social factors that cause these differences.

Abstract 634: The impact of IL-4 on migration in triple negative breast cancer cell lines

Abstract In the United States, triple-negative breast cancer (TNBC), an aggressive form of breast cancer (BCa), disproportionately affects women of African descent and contributes to racial disparities in BCa mortality. Various risk factors are thought to drive this disparity, including socioeconomic status, tumor characteristics, comorbidities, and quality of treatment. Complex diseases and environmental insults all invoke and/or disrupt host inflammation, with individual immune and variable responses to therapeutic agents being dictated in part by genetic variants. This latter has seldom been studied with regards to precision diagnosis and prognosis of individual patient responses, in the frame of geographical ancestry and TNBC. Interleukin-4 receptors (IL4R) have been shown to be upregulated in many epithelial cancers and could be a promising target for metastatic tumor therapy. Yet, IL4R overexpression and/or IL4R variants have not been evaluated in TNBC cell lines of varying genetic ancestry. In view of this, we investigated the effects of IL-4 treatment in four TNBC cell lines varying in proportions of West African Ancestry (WAA) in each cell line: MDA-MB-231 (0.019), HCC-1143 (0.012), HCC-1806 (0.807), MDA-MB-468 (0.803). The frequency of IL4R variants also differed in each cell line. We used high content live cell imaging to evaluate the effect of IL-4 treatment on cellular migration by measuring wound healing. We show that IL-4 treatment on TNBC cells enhances migration as indicated by increased wound healing when compared to non-treated cells. High glucose, at a concentration of 10 g/L, delays cell migration in IL4-treated TNBC cells. This data suggests that comorbidities, such as high glucose levels (i.e., uncontrolled diabetes) could impact tumor behavior and mortality disparities between populations. Citation Format: Portia Andrews, Kevin S. Kimbro. The impact of IL-4 on migration in triple negative breast cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 634.

Abstract PD1-03: Neighborhood deprivation and breast cancer mortality among Black and White women

Abstract Background: Neighborhood deprivation is hypothesized as a potential driver of racial disparities in breast cancer mortality. However, research shows that neighborhood deprivation is associated with increased breast cancer mortality among White women, but has little to no association among Black women. No study has previously considered the intersections of race, social cohesion, or urban/rural status in the association between neighborhood deprivation and breast cancer mortality. Methods: Neighborhood deprivation was examined in relation to breast cancer mortality among 31,358 non-Hispanic Black and non-Hispanic White women diagnosed with invasive breast cancer (stage I-IIIA) between 2010-2017, followed through 2019, and identified by the Georgia Cancer Registry. Two composite scores, the Area Deprivation Index (ADI) and neighborhood deprivation index (NDI), were used to characterize neighborhood deprivation. A third composite score, the Yost index, was assessed as a measure of neighborhood socioeconomic status (SES). Each composite score was composed of factors representing six domains: poverty, income, occupation, housing, employment, and education. Data on ADI were obtained from the Neighborhood Atlas and was assessed in deciles. American Community Survey data from 2011-2015 and principal components analysis were used to derive the NDI and Yost index. Both measures were assessed in quartiles. Each composite variable was measured at the block group level and linked to patient data. Cox proportional hazards regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between each composite variable and breast cancer mortality, overall and by race/ethnicity. Intersectionality will be examined by considering the joint effects of race/ethnicity, social cohesion, and urban/rural status. Results: During the 9-year follow-up period, 2,353 (1,347 non-Hispanic White, 1,006 non-Hispanic Black) women died from breast cancer. Regardless of which composite score was assessed, living in the most deprived or lowest SES neighborhoods was associated with an increased risk of breast cancer mortality in models adjusted for age and race (ADI decile 10 vs. 1: HR=1.57, 95% CI 1.26-1.96; NDI quartile 4 vs. 1: HR=1.43, 95% CI 1.26-1.63; Yost index quartile 1 vs 4: HR= 1.34, 95% CI 1.18-1.51). Stratification by race/ethnicity showed associations were slightly stronger among non-Hispanic White women but null among non-Hispanic Black women. Results from analyses examining the joint effects of race/ethnicity, social cohesion, and urban/rural status are forthcoming and will be presented in December. Conclusions: Consistent with previous studies, our study found that living in a deprived neighborhood may increase breast cancer mortality among non-Hispanic White women, but not non-Hispanic Black women. Investigating the association with an intersectionality framework may help identify subgroups of women who are particularly susceptible to the adverse impact of neighborhood deprivation on breast cancer mortality. Citation Format: Lauren E. Barber, Jasmine M. Miller-Kleinhenz, Maret L. Maliniak, Leah Moubadder, Jeffrey Switchenko, Lauren E. McCullough. Neighborhood deprivation and breast cancer mortality among Black and White women [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD1-03.

Abstract PD1-01: The Impact of Structural Racism on Breast Cancer Stage at Presentation

Abstract Background: Despite advances in diagnosis and treatment, racial and economic disparities in breast cancer-specific survival persist and this is exacerbated by later stage at presentation. It is essential to assess the factors that contribute to later stage at presentation to target racial and socioeconomic disparities in breast cancer mortality. The objective of this study was to analyze the effect of neighborhood socioeconomic status (SES) and race/ethnicity, as measured by the Index of Concentration at the Extremes (ICE), on breast cancer stage at presentation in a diverse metropolitan area that mirrors the projected demographics of many US regions. Methods: Patients treated at our medical campus, comprised of a safety-net hospital and an academic cancer center, with stage I-IV breast cancer from 2005-2017 were identified from our tumor registry. Census tracts were used as neighborhood proxies. Using 5-year estimates from the American Community Survey, 5 ICE variables were computed: economic (high vs. low), race/ethnicity (non-Hispanic White (NHW) vs. non-Hispanic Black (NHB) and NHW vs. Hispanic) and racialized economic (low-income NHB vs high-income NHW and low-income Hispanics vs. high-income NHW) segregation. ICE uniquely captures spatial economic and racial/ethnic segregation by mapping social inequality not otherwise captured by evaluating a population of a specific socioeconomic level or belonging to a particular racial/ethnic group. We used five separate models based on each of the ICE variables to evaluate economic and racial/ethnic segregation. Model 1 captures economic segregation (high vs. low), Model 2 captures racial segregation (NHB vs. NHW), Model 3 evaluates racialized economic segregation (low-income NHB vs high-income NHW), Model 4 captures segregation by Hispanic ethnicity (Hispanic vs. Non-Hispanic), and Model 5 captures ethnic and economic segregation (low-income Hispanics vs. high-income NHW). Our main outcome was breast cancer stage at presentation categorized as early (Stage I and II) vs. late (Stage III and IV) disease. All models controlled for the following covariates: race/ethnicity, age, insurance status, tumor subtype, and comorbidities including hypertension, diabetes, coronary artery disease, and hyperlipidemia. Results: The study population included 6,145 breast cancer patients. 52.6% were Hispanic, 26.3% were NHW, and 17.2% were NHB. Those living in the most economically marginalized neighborhoods (Quartiles 1 and 2) had significantly increased odds of presenting with later stage disease [ORQ1 1.36 (1.13-1.64), ORQ2 1.43 (1.18-1.75); p&amp;lt; 0.05]. Those living in the most racial/ethnic and economically marginalized neighborhoods (Quartile 1 of Models 3 and 5) had statistically significantly increased odds of presenting with later stage after controlling for all covariates compared to a NHW living in more economically advantaged neighborhoods [ORModel3 1.55 (1.21-1.99), ORModel5 1.43 (1.11-1.85); p&amp;lt; 0.05]. Conclusions: This study is the first to evaluate stage at presentation by ICE, which allows us to uniquely evaluate how residential racial and economic segregation may influence breast cancer disparities. Our study shows that patients in the most economically and racial/ethnically marginalized neighborhoods were more likely to present with later stage disease. This suggests that structural racism is influencing stage at presentation, and therefore effecting racial and economic disparities in breast cancer, even when accounting for demographics and tumor characteristics. To address these disparities, effective interventions are needed that account for the social and environmental contexts in which cancer patients live and can access care. Table 1: Odds Ratios for Later Stage at Presentation with Breast Cancer by Different Types of Residential Segregation Model 1: Economic segregation (high-income vs low-income) Model 2: NHB vs NHW segregation Model 3: NHB and economic segregation (low-income NHB vs high-income NHW) Model 4: Hispanic vs NHW segregation Model 5: Hispanic and economic segregation (low-income Hispanics vs. high-income NHW) Q1: Most disadvantaged neighborhoods; Q4: Reference: most advantaged neighborhoods. *p &amp;lt; 0.05 Citation Format: Alexandra Hernandez, Brianna L Cohen, Ashly Westrick, Cheyenne Thompson, Susan Kesmodel, Neha Goel. The Impact of Structural Racism on Breast Cancer Stage at Presentation [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD1-01.

Population-based temporal trends and ethnic disparity in breast cancer mortality in South Africa (1999-2018): Joinpoint and age-period-cohort regression analyses.

Joinpoint regression analyses of the trends in crude and age-standardized mortality rates (ASMR) of breast cancer among South African women were conducted from 1999 to 2018 using mortality data from Statistics South Africa. Age-period-cohort regression analysis was then conducted to evaluate the independent effect of age, period, and cohort on breast cancer mortality, and analysis was stratified by ethnicity. The mortality rate of breast cancer (from 9.82 to 13.27 per 100,000 women) increased at around 1.4% per annum (Average Annual Percent Change (AAPC): 1.4%, 95% CI:0.8-2.0, P-value< 0.001). Young women aged 30-49 years (1.1%-1.8%, P-value< 0.001) had increased breast cancer mortality. The risk of breast cancer mortality increased among successive birth cohorts from 1924 to 1928 but decreased among recent cohorts born from 1989 to 1993. In 2018, the breast cancer mortality rate among Blacks (9.49/100,000 women) was around half of the rates among the non-Blacks. (Coloreds: 18.11 per 100,000 women; Whites: 17.77/100,000 women; Indian/Asian: 13.24 per 100,000 women). Contrary to the trends in high- and middle-income countries, breast cancer mortality increased in South Africa especially among young women. Breast cancer prevention programs should be intensified and should also target young women. The marked disparity in ethnic burden of breast cancer should be considered during planning and implementation of interventions.