Sharing genetic test results with family members of BRCA, PALB2, CHEK2, and ATM carriers

OBJECTIVE

This study explored motivators and challenges/barriers to sharing personal genetic test results (GTR) with family members (FM).

METHODS

Semi-structured, in-depth interviews were conducted with 62 women who had a pathogenic or likely pathogenic (P/LP) variant in aBRCA, PALB2, CHEK2, or ATM gene. Selective qualitative data analysis focused on eliciting motivators and challenges/barriers identified by participants when sharing their GTR with FM.

RESULTS

Motivators to sharing personal GTR with FM included: health protection and prevention; moral obligation; decisional empowerment; familial ties; written resources; and contextualization for a familial cause for cancer. Challenges/barriers to family sharing included: concern for FM reactions; complexities of information; lack of closeness; perceived relevance; and emotional impact.

CONCLUSIONS

All motivators and challenges/barriers were identified across BRCA and non-BRCA carriers, demonstrating commonalities in family sharing of GTR among high- to moderate-penetrance hereditary BC (breast cancer) genes. Despite challenges/barriers, participants disclosed their GTR with most close FM, yet restrictions in communication and/or strain on the timing, manner of disclosing, and strategies used varied across certain FM.

PRACTICE IMPLICATIONS

These findings offer healthcare providers and researchers preliminary practical implications for broadly improving family sharing interventions across P/LP variants in BC risk genes by demonstrating important elements to include in family sharing letters.

A Web-Based Tool to Automate Portions of Pretest Genetic Counseling for Inherited Cancer

BACKGROUND

Increasing demand for genetic testing for inherited cancer risk coupled with a shortage of providers trained in genetics highlight the potential for automated tools embedded in the clinic process to meet this demand. We developed and tested a scalable, easy-to-use, 12-minute web-based educational tool that included standard pretest genetic counseling elements related to panel-based testing for multiple genes associated with cancer risk.

METHODS

The tool was viewed by new patients at the Vanderbilt Hereditary Cancer Clinic before meeting with a board-certified genetics professional. Pre- and post-tool surveys measured knowledge, feeling informed/empowered to decide about testing, attitudinal values about genetic testing, and health literacy. Of the initial 100 participants, 50 were randomized to only have knowledge measured on the post-tool survey to assess for a priming effect.

RESULTS

Of 360 patients approached, 305 consented and completed both the pre- and post-tool surveys, with a mean age of 47 years, including 80% female patients and 48% patients with cancer. Survey results showed an increase in knowledge and feeling informed/empowered after viewing the tool (P<.001), but no significant change in attitude (P=.64). Post-tool survey data indicated no difference in median knowledge between low and high health literacy groups (P=.30). No priming effect was present among the initial 100 participants (P=.675).

CONCLUSIONS

Viewing the educational tool resulted in significant gains in knowledge across health literacy levels, and most individuals felt informed and empowered to decide about genetic testing. These findings indicate that the use of an automated pretest genetic counseling tool may help streamline the delivery of genetic services.

Impact of molecular subtype and race on HR+, HER2- breast cancer survival

PURPOSE

There is an urgent need to understand the biological factors contributing to the racial survival disparity among women with hormone receptor-positive (HR+), HER2- breast cancer. In this study, we examined the impact of PAM50 subtype on 10-year mortality rate in women with HR+, HER2- breast cancer by race.

METHODS

Women with localized, HR+, HER2- breast cancer diagnosed between 2002 and 2012 from two population-based cohorts were evaluated. Archival tumors were obtained and classified by PAM50 into four molecular subtypes (i.e., luminal A, luminal B, HER2-enriched, and basal-like). The molecular subtypes within HR+, HER2- breast cancers and corresponding 10-year mortality rate were compared between Black and Non-Hispanic White (NHW) women using Cox proportional hazard ratios and survival analysis, adjusting for covariates.

RESULTS

In this study, 318 women with localized, HR+, HER2- breast cancer were included-227 Black (71%) and 91 NHW (29%). Young Black women (age ≤ 50) had the highest proportion of HR+, non-luminal A tumors (47%), compared to young NHW (10%), older Black women (31%), and older NHW (30%). Overall, women with HR+, non-luminal A subtypes had a higher 10-year mortality rate compared to HR+, luminal A subtypes after adjustment for age, stage, and income (HR 4.21 for Blacks, 95% CI 1.74-10.18 and HR 3.44 for NHW, 95% CI 1.31-9.03). Among HR+, non-luminal A subtypes there was, however, no significant racial difference in 10-yr mortality observed (Black vs. NHW: HR 1.23, 95% CI 0.58-2.58).

CONCLUSION

Molecular subtype classification highlights racial disparities in PAM50 subtype distribution among women with HR+, HER2- breast cancer. Among women with HR+, HER2- breast cancer, racial survival disparities are ameliorated after adjusting for molecular subtype.

Family communication of genetic test results among women with inherited breast cancer genes

Identification of inherited breast cancer may guide care. These benefits can be amplified through communication of genetic test results with at-risk family members and subsequent family testing (FT). Females with a pathogenic/likely pathogenic (P/LP) variant in BRCA1/2, PALB2, CHEK2, and/or ATM were surveyed about family communication (FC) of genetic test results and FT. Comparisons were made across genes. The 235 participants with P/LP variants (186 BRCA1/2, 28 PALB2, 15 CHEK2, and 6 ATM) had a median age of 54 and most were non-Hispanic whites (89%) with a prior breast cancer diagnosis (61%). When controlling for other variables, FC was higher among younger participants (p<.0001), those with high FC self-efficacy (p=.019), and those with P/LP variants in BRCA1/2 compared to PALB2 (p =.040) and ATM/CHEK2 (p =.032). Higher rates of FC and FT were also observed among female relatives and relatives of closer kinship. Overall 94% of participants would find one or more resources helpful with FC and 70% reported using FC resources when telling family members about their genetic test result. The three most commonly used resources included the following: (a) a family sharing letter (38%); (b) printed materials (30%); and (c) web-based information (23%). Among the 86% who spoke with a genetic counselor (GC), 93% were given at least one FC resource and the three most common resources GCs provided to participants overlapped with the resources participants would find helpful and those that were used. Our results suggest lower FC and FT rates among women with P/LP variants in genes other than BRCA1/2, the reasons for which should be evaluated in future studies. As more data to refine cancer risks and management are generated across these other inherited breast cancer genes, strategies to improve FC and FT are needed to amplify the benefits of genetic testing.

IMProving care After inherited Cancer Testing (IMPACT) study: protocol of a randomized trial evaluating the efficacy of two interventions designed to improve cancer risk management and family communication of genetic test results

BACKGROUND

Implementing genetic testing for inherited cancer predisposition into routine clinical care offers a tremendous opportunity for cancer prevention and early detection. However, genetic testing itself does not improve outcomes; rather, outcomes depend on implemented follow-up care. The IMPACT study is a hybrid type I randomized effectiveness-implementation trial to simultaneously evaluate the effectiveness of two interventions for individuals with inherited cancer predisposition focused on: 1) increasing family communication (FC) of genetic test results; and 2) improving engagement with guideline-based cancer risk management (CRM).

METHODS

This prospective study will recruit a racially, geographically, and socioeconomically diverse population of individuals with a documented pathogenic/likely pathogenic (P/LP) variant in an inherited cancer gene. Eligible participants will be asked to complete an initial trial survey and randomly assigned to one of three arms: A) GeneSHARE, a website designed to increase FC of genetic test results; B) My Gene Counsel's Living Lab Report, a digital tool designed to improve understanding of genetic test results and next steps, including CRM guidelines; or C) a control arm in which participants continue receiving standard care. Follow-up surveys will be conducted at 1, 3, and 12 months following randomization. These surveys include single-item measures, scales, and indices related to: 1) FC and CRM behaviors and behavioral factors following the COM-B theoretical framework (i.e., capability, opportunity, and motivation); 2) implementation outcomes (i.e., acceptability, appropriateness, exposure, and reach); and 3) other contextual factors (i.e., sociodemographic and clinical factors, and uncertainty, distress, and positive aspects of genetic test results). The primary outcomes are an increase in FC of genetic test results (Arm A) and improved engagement with guideline-based CRM without overtreatment or undertreatment (Arm B) by the 12-month follow-up survey.

DISCUSSION

Our interventions are designed to shift the paradigm by which individuals with P/LP variants in inherited cancer genes are provided with information to enhance FC of genetic test results and engagement with guideline-based CRM. The information gathered through evaluating the effectiveness and implementation of these real-world approaches is needed to modify and scale up adaptive, stepped interventions that have the potential to maximize FC and CRM.

TRIAL REGISTRATION

This study is registered at Clinicaltrials.gov (NCT04763915, date registered: February 21, 2021).

PROTOCOL VERSION

September 17th, 2021 Amendment Number 04.

Enhancing Cancer care of rural dwellers through telehealth and engagement (ENCORE): protocol to evaluate effectiveness of a multi-level telehealth-based intervention to improve rural cancer care delivery

BACKGROUND

Despite lower cancer incidence rates, cancer mortality is higher among rural compared to urban dwellers. Patient, provider, and institutional level factors contribute to these disparities. The overarching objective of this study is to leverage the multidisciplinary, multispecialty oncology team from an academic cancer center in order to provide comprehensive cancer care at both the patient and provider levels in rural healthcare centers. Our specific aims are to: 1) evaluate the clinical effectiveness of a multi-level telehealth-based intervention consisting of provider access to molecular tumor board expertise along with patient access to a supportive care intervention to improve cancer care delivery; and 2) identify the facilitators and barriers to future larger scale dissemination and implementation of the multi-level intervention.

METHODS

Coordinated by a National Cancer Institute-designated comprehensive cancer center, this study will include providers and patients across several clinics in two large healthcare systems serving rural communities. Using a telehealth-based molecular tumor board, sequencing results are reviewed, predictive and prognostic markers are discussed, and treatment plans are formulated between expert oncologists and rural providers. Simultaneously, the rural patients will be randomized to receive an evidence-based 6-week self-management supportive care program, Cancer Thriving and Surviving, versus an education attention control. Primary outcomes will be provider uptake of the molecular tumor board recommendation and patient treatment adherence. A mixed methods approach guided by the Consolidated Framework for Implementation Research that combines qualitative key informant interviews and quantitative surveys will be collected from both the patient and provider in order to identify facilitators and barriers to implementing the multi-level intervention.

DISCUSSION

The proposed study will leverage information technology-enabled, team-based care delivery models in order to deliver comprehensive, coordinated, and high-quality cancer care to rural and/or underserved populations. Simultaneous attention to institutional, provider, and patient level barriers to quality care will afford the opportunity for us to broadly share oncology expertise and develop dissemination and implementation strategies that will enhance the cancer care delivered to patients residing within underserved rural communities.

TRIAL REGISTRATION

Clinicaltrials.gov , NCT04758338 . Registered 17 February 2021 - Retrospectively registered, http://www.clinicaltrials.gov/.

Disparities in BRCA counseling across providers in a diverse population of young breast cancer survivors

PURPOSE

All women diagnosed with breast cancer (BC) ≤age 50 should be referred for genetic counseling (GC) and testing. We sought to compare differences in provider practices and access across a racially and ethnically diverse population of young BC survivors.

METHODS

A registry-based sample of women diagnosed with invasive BC ≤age 50 from 2009 to 2012 was recruited through the Florida Cancer Registry, and completed a questionnaire and medical record release. Differences were compared across those tested with or without the involvement of a board-certified or credentialed genetics health professional (GHP) in (1) clinical and demographic variables and (2) pretest GC elements.

RESULTS

Of 1622 participants, there were 440 Blacks, 285 Hispanics, and 897 Non-Hispanic Whites. Of 831 participants with medical record verification of testing provider, 170 (20%) had documentation of GHP involvement. Among the 613 who recalled a pretest discussion and had GC elements collected, those with GHP involvement were significantly more likely to recall the seven recognized GC elements.

CONCLUSION

GHP involvement was associated with adherence to nationally recommended best practices. With the expanding importance of identifying inherited cancers, it is critical to ensure equitable access to best practices across all populations.

Caring for Individuals with Chronic Illness and Minor Depression: Latino Perceptions of Caregiver Burden

Informal caregiving can be fundamental to disease management. Yet, the psychosocial, physical, and financial burden experienced by caregivers can be significant. In the US, Latinos experience increasing rates of chronic conditions, the highest uninsured rates in the country, and a growing dependence on informal caregivers. This article explores the impact of caregiving on caregivers of individuals with comorbid chronic disease and depression. Findings highlight the impact of caregiving on financial insecurity, balancing competing demands, increased emotional distress, and community supports. Findings support the inclusion of caregivers in disease management programs to enhance psychosocial outcomes for both caregivers and their patients.

Breast cancer screening implications of risk modeling among female relatives of ATM and CHEK2 carriers

BACKGROUND

With the increasing use of multigene panel tests, pathogenic and likely pathogenic (P/LP) variants are identified more frequently in the moderate-penetrance breast cancer genes ATM and CHEK2. Lifetime breast cancer risk among women with P/LP variants in these genes generally exceeds 20%, meeting the threshold at which high-risk breast cancer screening through breast magnetic resonance imaging (MRI) is recommended.

METHODS

Among a registry-based sample of 56 ATM and 69 CHEK2 carriers, the authors sought to determine the percentage of relatives in whom a P/LP variant would impact breast cancer surveillance. Lifetime breast cancer risks for unaffected, female first-degree and second-degree relatives were estimated using the Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA).

RESULTS

Among first-degree relatives of ATM and CHEK2 carriers, only 22.6% and 14.9%, respectively, were found to have lifetime breast cancer risks of ≥20% based on family cancer history alone; however, when including the proband's P/LP variant in the model, these percentages increased significantly to 56.6% and 55.3%, respectively (P < .0001 and P < .0001, respectively). Similar increases in lifetime breast cancer risks were found among second-degree relatives.

CONCLUSIONS

The results of the current study suggest that the majority of female first-degree and second-degree relatives of ATM and CHEK2 carriers do not qualify for breast MRI based on family cancer history alone. Therefore, testing for these genes, as well as awareness of positive moderate-penetrance breast cancer gene results in the family, may impact MRI eligibility. These findings highlight the potential usefulness of and need for breast cancer risk models that incorporate moderate-penetrance gene positivity to inform screening recommendations among at-risk family members.

A Pooled Case-only Analysis of Reproductive Risk Factors and Breast Cancer Subtype Among Black Women in the Southeastern United States

BACKGROUND

We investigated the association between reproductive risk factors and breast cancer subtype in Black women. On the basis of the previous literature, we hypothesized that the relative prevalence of specific breast cancer subtypes might differ according to reproductive factors.

METHODS

We conducted a pooled analysis of 2,188 (591 premenopausal, 1,597 postmenopausal) Black women with a primary diagnosis of breast cancer from four studies in the southeastern United States. Breast cancers were classified by clinical subtype. Case-only polytomous logistic regression models were used to estimate ORs and 95% confidence intervals (CI) for HER2⁺ and triple-negative breast cancer (TNBC) status in relation to estrogen receptor-positive (ER⁺)/HER2^- status (referent) for reproductive risk factors.

RESULTS

Relative to women who had ER⁺/HER2^- tumors, women who were age 19-24 years at first birth (OR, 1.78; 95% CI, 1.22-2.59) were more likely to have TNBC. Parous women were less likely to be diagnosed with HER2⁺ breast cancer and more likely to be diagnosed with TNBC relative to ER⁺/HER2^- breast cancer. Postmenopausal parous women who breastfed were less likely to have TNBC [OR, 0.65 (95% CI, 0.43-0.99)].

CONCLUSIONS

This large pooled study of Black women with breast cancer revealed etiologic heterogeneity among breast cancer subtypes.

IMPACT

Black parous women who do not breastfeed are more likely to be diagnosed with TNBC, which has a worse prognosis, than with ER⁺/HER2^- breast cancer.

Inherited Cancer Knowledge Among Black Females with Breast Cancer Before and After Viewing a Web-Based Educational Video

Purpose: Scalable solutions are needed to make pre-test genetic education about inherited cancer risk accessible across diverse and underserved populations. We evaluated an automated strategy to deliver genetic education through a web-based video among young Black females with breast cancer. Methods: 96 participants were recruited through state cancer registries in Florida and Tennesee. All participants viewed a 12 min video and completed a ten question quiz on inherited cancer knowledge before and after viewing the video. Median pre- and postvideo knowledge scores were categorized as <60% versus ≥60% and compared across demographic and clinical characteristics using binary logistic regression. Results: Of the 96 participants, mean age was 51, over 50% had income <$50 K, over 40% did not graduate college or have private insurance, and over 70% had previous genetic testing. Median knowledge scores significantly increased after viewing the video (p < 001), with no significant differences in those with or without prior testing. A higher post-video knowledge score was associated with an income ≥$50 K, a college degree, and private insurance (all p < .05). Conclusion: Among a population of young Black breast cancer patients, the educational video significantly increased knowledge. Findings support the use of automated pre-test educational tools as a scalable solution to make these services more accessible across populations.

Applying the framework for developing and evaluating complex interventions to increase family communication about hereditary cancer

Objective

Evaluate an intervention to increase family communication (FC) of positive hereditary cancer test results using the Framework for Developing and Evaluating Complex Interventions (FDECI).

Methods

We developed 'programme theory' during the FDECI development phase by aligning intervention components with behavior change techniques (BCTs) and theoretical factors expected to improve FC. During the feasibility phase, we obtained feedback from 12 stakeholder interviews.

Results

Intervention components aligned with a total of 14 unique BCTs for which prior evidence links the BCT to theoretical factors that influence behavior change. Constructive stakeholder feedback included: more information desired, rewording to support autonomy by highlighting options, and improvements to navigation, visuals, and audio. Positive comments included: comprehensiveness of materials, modeling of conversations, and usefulness of the materials for helping a person prepare to share positive test results.

Conclusion

The first FDECI phases were helpful for improving the intervention and planning our ongoing effectiveness and future implementation phases.

Innovation

Our application of the FDECI is novel, including plans to test our 'programme theory' using coincidence analysis (CNA) to determine who accesses which intervention materials, how utilizing certain materials impact the aligned theoretical factors, and whether these in turn make a difference in the behavioral outcome.

Cancer risk management and family communication of genetic test results among women with inherited breast cancer genes

1532

Background: Identification of inherited breast cancer may guide care, with benefits amplified through family testing. Methods: Females with a pathogenic/likely pathogenic (P/LP) variant in BRCA1/2, PALB2, CHEK2, and/or ATM were surveyed about cancer risk management, family communication of genetic test results, and family testing. Comparisons were made across genes. Results: The 235 participants with P/LP variants (186 BRCA1/2, 28 PALB2, 15 CHEK2, and 6 ATM) had a median age of 54 and 61% had a prior breast cancer diagnosis. For women with P/LP variants in BRCA1/2, PALB2, and ATM/CHEK2, bilateral mastectomy rates were 79%, 61%, and 52%, respectively; and risk-reducing oophorectomy rates were 89%, 30%, and 37%, respectively. All women with PALB2 and ATM/CHEK2 P/LP variants with a bilateral mastectomy had a personal or family history of breast cancer; however, only 27% of those with a risk-reducing oophorectomy had a family history of ovarian cancer. Family communication of genetic test results and family testing rates were higher for those with P/LP variants in BRCA1/2 compared to others. Conclusions: Bilateral mastectomy and risk-reducing oophorectomy were relatively common among women with PALB2 and ATM/CHEK2 P/LP variants in our study, suggesting overtreatment through risk-reducing surgery. Furthermore, strategies to improve family communication of genetic test results and family testing are needed to amplify testing benefits.

Disparities in pretest genetic counseling among a population-based sample of young breast cancer patients

1579

Background: Per national practice guidelines, pre-test genetic counseling (GC) through a board-certified or credentialed genetics health professional (GHP) is recommended when testing for hereditary cancer. We sought to compare differences in rates of pre-test GC among young breast cancer (BC) patients tested with or without GHP involvement across three racial groups (Black, Hispanic and non-Hispanic white (NHW)). Methods: A population-based sample of Black, Hispanic and NHW women diagnosed with invasive BC ≤ age 50 from 2009 to 2012 were recruited through the Florida State Cancer Registry. Participants were asked to complete a baseline questionnaire and release medical records for verification of clinical information and genetic testing. We compared the rates of pre-test GC across racial groups in women tested with or without GHP involvement using Analysis of Variance. Multivariate logistic regression analysis was also conducted to adjust for potential confounders. Results: Of 1618 participants, 828 had genetic testing based on medical records and/or self-reported on their questionnaire. There were 170 (20.5%) with GHP involvement (either through consultation and/or test ordering) and the remaining 658 women (79.5%) had no documentation of GHP involvement. Among patients tested without GHP involvement, rates of pre-test GC were significantly lower among Black women (34.8%) compared to Hispanics (80%) and NHW (78.7%) (p < 0.001). In contrast, among those with GHP involvement, rates of pre-test GC were similar among Black (89.7%), Hispanic (81.1%) and NHW (84.6%) (p = 0.89). Conclusions: Our results suggest that among young breast cancer patients tested for hereditary cancer without GHP involvement, Blacks were significantly less likely to receive pre-test GC, compared to the other two groups. In contrast, rates of pre-test GC among those with GHP involvement were similar across all groups. These results suggest a disparity in receipt of pre-test GC (which is standard of care per national guidelines) among Blacks tested without GHP involvement. These findings are concerning given the need to offer guideline-adherent care to all patients receiving hereditary cancer testing.

Abstract B056: Assessing knowledge of genetic testing for inherited cancer among registry-based young black breast cancer survivors and predominantly non-Hispanic white clinic-based patients

Introduction: Practice guidelines put forth through the American Society of Clinical Oncology (ASCO) evolved to encompass a new method of testing whereby multiple genes are tested in parallel (i.e., multi-gene panel testing) and racial disparities in genetic testing rates persist. To measure and compare knowledge of inherited cancer predisposition and multi-gene panel testing across racially diverse patient groups, we administered a newly developed and validated knowledge scale aligned with the 2016 ASCO guidelines. Methods: Online survey data inclusive of 14 knowledge questions was collected among Black women diagnosed with breast cancer at or below age 50 recruited through the Tennessee and Florida state cancer registries (“Registry group”; N=39) and an insured, predominately non-Hispanic White patient population referred for cancer genetic risk assessment at the Vanderbilt Hereditary Cancer Clinic (“Clinic group”; N= 55). Demographic and clinical information were compared using Chi-Square and Fisher’s Exact tests. Mean knowledge scores were calculated and compared using multiple regression analysis. Results: Rates of cancer among the Registry and Clinic groups were 100% and 49% (p&lt;.0001), and rates of previous genetic testing were 69% and 13% (p&lt;.0001). Mean knowledge scores were 6.10 and 6.75. When controlling for race, cancer history, and previous genetic testing, knowledge was not significantly different between the two groups (p=0.507). The lowest scoring knowledge questions among the Registry and Clinic groups included: 1) understanding of a variant of uncertain significance (15% and 11%); 2) knowledge of impact of genetic test results on supplemental insurance (21% and 11%); and 3) the types of possible test results (15% and 18%). Conclusion: These findings demonstrate similar knowledge of inherited cancer predisposition between a predominantly non-Hispanic White clinic-based population and a registry-based population of young Black breast cancer survivors; however, additional analyses should be performed as sample size increases. Knowledge about the possible results of genetic testing and the lack of protection against discrimination by supplemental insurers (e.g., life and disability insurance) was low across both groups; thus, should be a focus for improvement given that it could have real-world implications for decision-making. It remains important to assess knowledge of inherited cancer across diverse patient groups to develop effective strategies and interventions to increase knowledge across populations, including those with recognized disparities.

Citation Format: Sydney Cadiz, Sonya Reid, Brenda Zuniga, Ann Tezak, Anne Weidner, Tuya Pal. Assessing knowledge of genetic testing for inherited cancer among registry-based young black breast cancer survivors and predominantly non-Hispanic white clinic-based patients [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr B056.

Abstract 2427: Patterns of BRCA testing by provider type based on biological and non-biological factors among a diverse sample of young breast cancer survivors

Introduction: Per national practice guidelines, pre-test genetic counseling through a provider experienced and proficient in genetics (such as a genetics health professional (GHP)) is recommended prior to genetic testing for hereditary cancer. We sought to determine if there are differences in clinical and demographic variables between young breast cancer (BC) survivors who saw a GHP prior to genetic testing compared to those tested without involvement of a GHP.

Methods: A population-based sample of Black, Hispanic and non-Hispanic white (NHW) women diagnosed with invasive BC &lt; age 50 in 2009-2012 was recruited through the Florida State Cancer Registry. Participants were asked to complete a questionnaire and medical records release to verify clinical information and genetic test results. Women tested through a GHP were compared to those tested through a non-GHP based on the following variables: 1) Socioeconomic status (SES) (income, college education and private insurance); 2) Racial group (Black, Hispanic and NHW); and 3) Clinical factors (age at diagnosis, family history (FH) of breast or ovarian cancer and triple negative breast cancer (TNBC) status) using Pearson chi-squared analyses.

Results: Of 1618 study participants, 1080 reported genetic counseling and/or testing, of which provider information was verified on 981 based on documentation in medical record and/or genetic test result report. GHP involvement (either through consultation and/or test ordering) was reported in 193 women (19.7%) whereas the remaining 788 women (80.3%) had no documentation of GHP involvement. There was a significantly higher rate of GHP involvement among women with TNBC compared to those without TNBC (26.1% vs. 19.1%; p=0.05); and non-significant increases in those with and without a FH of BC (21.1% vs. 17.6%; p=0.17); and ovarian cancer (22.8% vs. 19.2%; p=0.34). GHP involvement did not vary among: 1) women diagnosed &lt; or &gt; age 45 (19.6% vs. 19.8%; p=0.96); 2) Blacks (20.1% vs. 19.6%; p=0.88); 3) Hispanics (23.5% vs. 18.8%; p=0.15); and 4) NHW (18.5% vs. 22%; p=0.19). Regarding SES-related indicators, GHP involvement was lower among women with private insurance versus those without (18.3% vs. 29.3%; p=0.002), annual household income &gt; $25,000 versus those &lt; $25,000 (18.8% vs. 30.8%; p=0.004) and a college education (55.4% vs. 60.9%; p=0.17).

Conclusions: Our results demonstrate that TNBC status was associated with testing through a GHP, while other clinical and demographic variables were not associated with GHP involvement. This finding may be due to widespread recognition of a more aggressive disease phenotype and association of TNBC with hereditary disease. Furthermore, the inverse relationship between higher SES-related indicators and GHP involvement suggests that those with higher SES are less likely to receive care through a GHP, as recommended per national guidelines.

Citation Format: Sonya Reid, Deborah Cragun, Ann Tezak, Anne Weidner, Ingrid Mayer, Xiao-ou Shu, Susan Vadaparampil, Tuya Pal. Patterns of BRCA testing by provider type based on biological and non-biological factors among a diverse sample of young breast cancer survivors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2427.

Abstract P3-14-11: Mammaprint and Blueprint identify genomic differences in HR+ HER2- breast cancers from young Black and White women

Introduction: Hormone receptor positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer, the most common immunohistochemical subtype, remains the dominant contributor to annual breast cancer deaths worldwide across all racial and ethnic groups. Black women are 41% more likely to die from breast cancer compared to White women, predominantly among women diagnosed ≤ 50 years of age. Yet, Black women remain underrepresented in clinical trials and population-based studies. Thus, it is critical to better characterize tumor molecular features from young Black women to identify factors contributing to the existing racial survival disparity. In the current study, we compared risk of distant recurrence signature, MammaPrint (MP), molecular subtyping signature, BluePrint (BP), and whole transcriptome differences between young Black women with HR+ HER2- breast cancer compared to matched White controls. Methods: This study included 156 Black women aged ≤ 50 with stage I-III, HR+ HER2- breast cancer of whom, 68 were recruited from 2009-2014 as part of the BEST study (5R01CA204819-04) with follow-up data available (median 114.5 months). The remaining 88 Black women were enrolled in the ongoing FLEX Study (NCT03053193) from 2017. White women (n=156) were randomly selected from FLEX and matched by age, tumor stage, and receptor status. Tumors were classified through MP as Low Risk (MP-LR) versus High Risk (MP-HR), with MP-HR further stratified into HR1 and HR2; HR2 tumors exhibit superior chemosensitivity as demonstrated in a prior large clinical trial of breast cancer patients (ISPY2). All women had MP and BP to classify tumors as Luminal A (MP-LR), Luminal B (MP-HR), HER2, or Basal, and full transcriptomic analyses. Differential gene expression analysis was performed with R package ‘limma’ to compare Black and White women and further compare within each molecular subtype. Differentially expressed genes (DEGs) with a false discovery rate &lt;0.05 were significant. Results: Of 312 young women with localized, HR+ HER2- breast cancer, high grade tumors were more frequent among Black compared to White women (34.6% vs 25.6%; p=0.08). MP-HR tumors were significantly more frequent among Black compared to White women (67.3% vs. 50.0%; p=0.002). Among MP-HR tumors, more HR2 tumors were seen in Black (25.6%) compared to White women (14.1%). Among women with MP-HR tumors and known treatment information, most Black women (94.3%) and all White women received chemotherapy. There were more Luminal B tumors in Black compared to White women (51.9% vs. 41.7%; p=0.07). BP reclassified a larger proportion of ER+ tumors as Basal in Black compared to White women (14.1% vs. 8.3%). Of 68 Black women with available survival data, 7 had death and/or distant recurrence events, of whom 6 (85.7%) had MP-HR tumors (4 Luminal B, 1 HER2, and 1 Basal) and 1 had MP-LR Luminal A tumor. Compared to White women, Black women with: 1) Luminal B tumors had 192 DEGs with upregulation of suspected poor prognosis genes, PSPH and IGHG1; 2) Luminal A tumors had upregulation of PSPH; and 3) Basal tumors had downregulation of POTEH. Conclusion: Among young women with localized HR+ HER2- breast cancer, MP and BP molecular signatures more robustly identified racial disparities in risk and subtype distribution beyond that identified through clinical factors adjusted for age and tumor characteristics. The transcriptomic differences among Black compared to White women across all BP subtypes provide novel insights about tumor biological differences. These findings have tremendous translational potential to identify etiologic underpinnings of racial survival disparities which may guide therapeutic strategies to improve outcomes.

Citation Format: Sonya Reid, Tuya Pal, Ingrid A. Mayer, Xiao-Ou Shu, Ann L. Tezak, Kent Hoskins, Dipali Sharma, Patricia Robinson, Jennifer Wei, Jake Ruby, Shiyu Wang, Josien Haan, Andrea Menicucci, William Audeh, FLEX Investigators Group. Mammaprint and Blueprint identify genomic differences in HR+ HER2- breast cancers from young Black and White women [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 P3-14-11.

West African Genetic Ancestry and Breast Cancer Outcomes Among Black Women

Importance

Young Black women bear a disproportionate burden of breast cancer deaths compared with White women, yet they remain underrepresented in genomic studies.

Objective

To evaluate the association of biological factors, including West African genetic ancestry, and nonbiological factors with disease-free survival (DFS) among young Black women with breast cancer.

Design, Setting, and Participants

This observational cohort study included Black women diagnosed with invasive breast cancer between January 1, 2005, and December 31, 2016. Participants diagnosed with breast cancer at age 50 years or younger were recruited through the Florida and Tennessee state cancer registries. The final analysis was completed between June and September 2024.

Exposure

West African genetic ancestry.

Main Outcomes and Measures

A multivariable model was developed to evaluate the association between West African genetic ancestry and breast cancer DFS, adjusting for immunohistochemistry subtype, lymph node (LN) status, and full-time employment.

Results

This study included 687 Black women with early-stage invasive breast cancer. Their median age at diagnosis was 44 years (IQR, 38-47 years), and the median follow-up was 10 years (IQR, 7-11 years). In multivariable analysis, triple-negative breast cancer (TNBC) and LN involvement were associated with shorter breast cancer DFS (hazard ratio, 1.81 [95% CI, 1.20-2.73] and 1.77 [95% CI, 1.30-2.41], respectively), whereas full-time employment was associated with improved outcomes (hazard ratio, 0.44 [95% CI, 0.30-0.63]). Among the 551 participants for whom global genetic ancestry could be assessed, having a higher percentage of West African genetic ancestry was associated with shorter breast cancer DFS among 246 participants in the hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (ERBB2 [formerly HER2])-negative subgroup (hazard ratio, 1.45 [95% CI, 1.04-2.04]). Of the 369 participants (53.7%) with PAM50 data available, basal (133 [36.0%]) and luminal B (107 [29.0%]) subtypes were the most common. Among the 179 patients with HR-positive/ERBB2-negative disease and PAM50 data available, luminal B and basal subtypes combined were also overrepresented (81 [45.3%] and 24 [13.4%], respectively) compared with luminal A (70 [39.1%]).

Conclusions and Relevance

In this study of young Black women with breast cancer, having a higher percentage of West African genetic ancestry, TNBC, and LN involvement were associated with shorter breast cancer DFS. Interestingly, full-time employment was associated with improved breast cancer DFS. These findings highlight the importance of considering genetic ancestry beyond self-reported race and accounting for social determinants of health, in efforts to improve survival outcomes among Black women with breast cancer.

Characterization of germline and tumor genomic profile in unselected young black breast cancer patients

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Background: Young black women bear a disproportionate burden of breast cancer (BC), yet there is limited characterization of these cancers based on BRCA1 and BRCA2 ( BRCA) status and tumor genomics. In this pilot study, we characterized: tumor and clinical characteristics based on BRCA carrier status and overlap of basal-like (BL) and triple negative (TN) BC. Methods: A population-based sample of 481 black women diagnosed with invasive BC < age 50 were recruited through the Florida Cancer Registry (FCR). BRCA status was determined based on germline testing. TN status was determined based on pathology reports and FCR data. Among a subset of 90 participants, gene expression profiling (GEP) was conducted on tumor samples through PAM50 analyses to classify intrinsic subtypes and risk of recurrence (ROR) scores. Results: Mean age at BC diagnosis was 41.9 (range: 25-50) and mean ROR score was 49.6 (range: 8.7-80.7). Participants included 7 BRCA1 carriers, 5 BRCA2 carriers, 67 non-carriers (NC), and 11 with no confirmed testing. Of 46 BL tumors, 33 were TN (71.7%) constituting 94.3% of TN tumors (the remaining 5.7% were Luminal A). All BRCA1 carriers had BL tumors, of which 5 were TN. Sensitivity, positive predictive value, and negative predictive value in identifying BRCA1 carrier was higher based on BL compared to TN status (Table 1). BRCA2-associated tumors included 3 Luminal A, 1 Luminal B, and 1 BL. Mean ROR score was highest among BRCA1 carriers (57.7), followed by NC (50.5) and BRCA2 carriers (41.5). Conclusions: Study findings suggest BL status predicted BRCA1 positivity better than TN status. BRCA2- (compared to BRCA1-) associated tumors were more heterogeneous with over half being Luminal A, which may explain the lower ROR among BRCA2 carriers. Additional follow-up and expansion of this cohort with collection of clinical outcomes will be useful in assessing the predictive utility of ROR scores among young black women with BC. [Table: see text]

The association between race and intrinsic subtype on hormone receptor-positive breast cancer among young black women

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Background: Hormone receptor-positive, HER2-negative breast cancer (HR+/HER2- BC) has the highest incidence and mortality rate across all racial/ethnic groups. HR+/HER2- BC is clinically and biologically heterogenous. Gene expression profiling assays can provide prognostic information and predict risk of late recurrence among women with HR+/HER2- BC. Prior studies have shown worse clinical outcomes among black women with HR+/HER2- BC. We sought to compare the distribution of intrinsic subtypes among young black women with HR+/HER2- BC, compared to published data from a young white cohort in the Carolina Breast Cancer Study (CBCS). Methods: Two population-based cohorts of black women diagnosed with BC between 2002 to 2012 at or below age 50 years were analyzed. Participants were recruited from twelve Southeastern states. All participants were asked to complete release of medical records and tissue/tumor forms to verify clinical information and to obtain primary tumor samples for future analyses. We compared the distribution of intrinsic subtypes and associations to clinical characteristics as compared to white female counterparts using Pearson chi-squared test. Results: Of 569 black participants, 124 women had HR+/HER2- BC and tumor samples available for analysis. There were 66 Luminal A (53%), 35 Luminal B (28%), 19 Basal (15%), and 4 HER2-enriched (3%) tumors. Black women with non-Luminal A tumors were younger ( < 40) with larger tumors ( > 2cm) and had higher risk of recurrence (ROR-T) scores as compared to black women with Luminal A tumors (p = 0.065, 0.006, and < 0.001, respectively). Compared to young white women in the CBCS, black women in our study had a significantly higher percentage of non-Luminal HR+/HER2- BC (p = 0.037). Conclusions: Our results suggest that among young women with HR+/HER2- BC, black women have a higher proportion of non-Luminal tumors compared to their white counterparts. Non-Luminal HR+/HER2- tumors (i.e., basal and HER2-enriched) are more aggressive and may be less sensitive to endocrine therapy. These results suggest that overrepresentation of aggressive HR+/HER2- BC subtypes may contribute to the racial survival disparity observed among black women.

Whole transcriptomic analysis of HR+ breast cancer in Black women classified as basal-type by BluePrint

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Background: Breast cancer is the leading cause of cancer-associated death among Black women, and they are 41% more likely to die from breast cancer compared to White women. Few studies have evaluated if tumor biology differences contribute to this disparity in outcomes. Similar to triple negative breast cancer (TNBC), hormone receptor-positive (HR+) tumors classified as Basal-Type with BluePrint genomic analysis (HR+/Basal) are more aggressive, higher grade, are over-represented among young Black women and have worse clinical outcomes. TNBC is associated with low ACKR1 expression, which encodes the Duffy antigen and correlates with worse breast cancer outcomes. Given the over-representation and worse outcomes among Black women with HR+/Basal tumors, we compared differentially expressed genes (DEGs) by race and subtype. Methods: This study includes 2657 women with Stage I-III breast cancer who received BluePrint testing and are participants of the ongoing BEST study (5R01CA204819) at Vanderbilt University Medical Center or FLEX study (NCT03053193). Of 455 Black women, 315 had Luminal (HR+/Luminal) and 140 had Basal tumors (66 HR+/Basal and 74 HR-/Basal). White women within FLEX (n = 2202) were included as a reference group with HR+/Luminal (n = 1825), HR+/Basal (n = 158), or HR-/Basal (n = 219) tumors. Two-tailed proportional z-test was used to assess differences in subtype proportion by race. Limma R package was used to perform differential gene expression analysis (DGEA) of whole transcriptome data. Significant DEGs had an adjusted p-value < 0.05 and absolute log2 fold change > 1. Results: Black women had a significantly higher proportion of HR+/Basal (15%; p < 0.001) and HR-/Basal (16%; p < 0.001) tumors compared to White women (7% and 10%, respectively). In a multidimensional scaling analysis, HR+/Basal tumors cluster with TNBC rather than with HR+/Luminal tumors. While a DGEA comparing HR+/Basal with HR+/Luminal tumors resulted in over 700 DEGs within Black women, no DEGs were identified when comparing HR+/Basal tumors with TNBC. ACKR1 expression in HR+/Basal tumors was comparable to TNBC in Black women (p = 0.81) and White women (p = 0.46). In contrast, HR+/Basal tumors had significantly lower ACKR1 expression than HR+/Luminal tumors in Black (p < 0.01) and White women (p < 0.01). Conclusions: In this racially diverse cohort, transcriptomic analyses suggest that HR+/Basal tumors are biologically analogous to TNBC, independent of race. Molecular profiling identified racial disparities in the proportion of HR+/Basal tumors and underscores the need for diverse representation in clinical trials. With an over-representation of HR+/Basal tumors in Black women and evidence of worse outcomes, these data suggest that patients with HR+/Basal tumors should not be treated uniformly with HR+/Luminal tumors and highlight the importance of further genomic classification for patients with HR+ tumors. Clinical trial information: NCT03053193.