4th Conference Research Articles

Abstract A080: Improving outcomes: Addressing racial and ethnic disparities in colorectal cancer genomic research

Abstract Colorectal cancer (CRC) is the fourth most common cancer diagnosed in the United States (U.S.). This disease presents notable health disparities among racial and ethnic minorities in the U.S. Native Americans (NA) and non-Hispanic Blacks (NHB) exhibit the highest incidence and mortality rates for CRC compared to non-Hispanic Whites (NHW). These disparities are driven by a combination of factors, including socioeconomic inequalities, access to healthcare, lifestyle habits, and genetic susceptibilities. Minority populations often face delays in diagnosis and treatment, leading to advanced disease stages at presentation and poorer outcomes. Addressing these disparities through cancer genomics is essential for developing effective, personalized treatments that can improve outcomes for underrepresented populations. Comprehensive genomic studies can reveal genetic mutations and biomarkers unique to these groups, facilitating targeted therapies and preventive measures tailored to their specific needs. To address these disparities, we conducted an analysis of U.S. population-based colorectal cancer studies within 3 cancer genomic databases: the National Cancer Institute’s Genomic Data Commons, the AACR Project GENIE, and cBioPortal. We identified 13 studies suitable for inclusion, calculating incidence percentages across all racial and ethnic categories. Our analysis encompassed a total of 20,295 patients. Among the analyzed patients, the racial distribution was as follows: NHW (68.5%), Asians (5.30%), NHB (7.7%), Other (5.6%), NA (0.2%), Pacific Islander/Native Hawaiian (0.07%), and not reported (12.7%). Ethnic data was missing for 24.1% (n=4,895) of the patients. Samples were predominantly from individuals identified as Not Hispanic (68.4%), while Hispanic individuals constituted 7.5%. Our results show significant underrepresentation of NHB, NA and Hispanic patients in CRC genomic databases highlighting a disparity between expected and actual representation. These findings underscore the critical need for inclusive research practices. Addressing these disparities in cancer genomics is imperative to develop equitable, effective treatments and improve health outcomes for all populations. Ensuring diverse representation in genomic databases will enhance the understanding of genetic differences across populations, inform targeted therapies, and ultimately contribute to reducing CRC disparities. By addressing these disparities, we can move towards a future where all populations benefit equally from advancements in CRC treatment and prevention, thus improving survival rates and quality of life for minority groups. Citation Format: Gabriela Arroyo Figueroa, Tim F. Greten, Cecilia Monge. Improving outcomes: Addressing racial and ethnic disparities in colorectal cancer genomic research [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A080.

Abstract A028: Revisiting cancer care inequities in Sub-Saharan Africa: standpoint and recommendations

Abstract Introduction: Cancer is a major global public health concern that claims around 2000 lives per day in Africa alone. Mortality rates are expected to rise in the absence of appropriate interventions. Equity and prioritizing are the main obstacles to cancer care in Africa, as policymakers and other stakeholders in the healthcare system do not give cancer enough attention. All aspects of the cancer care continuum especially these three main levels of cancer care—prevention, diagnosis, and treatment/management—are negatively impacted by this neglect. Addressing concerns of equity and prioritizing is essential to promoting equality in cancer care, as it guarantees that all individuals have an equal opportunity at cancer prevention, early detection, appropriate therapy, and follow-up treatment. Methods: We present an overview of the current status of cancer care in Africa and offer recommendations to bridge the gap using the material currently accessible from recognized databases. Results: Insufficient funding for cancer research, inadequate screening or diagnostic facilities, a lack of a well-organized and efficient cancer registry system and access to care, a shortage of specialized medical staff, high costs for screening, vaccination, and treatment, a lack of technical capacity, poor vaccination response, and late patient presentation for cancer screening are some of the factors that we highlighted as contributing to the disparity in cancer care in Africa. We also offer suggestions on overcoming some of these barriers to achieving fairness in cancer care. Our recommendations are broken down into capacity-based and national-level initiatives. These include improving healthcare budgeting for personnel, supplies, and facilities; encouraging screening and vaccine uptake; raising awareness of cancer health among medical professionals during every hospital visit, gaining knowledge through specialized training, financing cancer research, offering cancer insurance, and putting mobile health technologies to use for telemedicine diagnosis.Conclusion: A comprehensive approach to addressing issues related to cancer equity would increase the chances of cancer patients surviving longer, reduce risk factors for at-risk groups, and guarantee fair access to cancer care across the continent. This report describes the present barriers to achieving equity in cancer care, identifies the African countries' current positions on the matter, and offers recommendations that could have the greatest impact on achieving equity in cancer care. Citation Format: John Oluwafemi Teibo, Olabode Omotoso, Festus Adebayo Atiba, Tolulope Oladimeji, Tomiwa Kehinde Paimo, Farid S. Ataya, Gaber El-Saber Batiha, Athanasios Alexiou. Revisiting cancer care inequities in Sub-Saharan Africa: standpoint and recommendations [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A028.

Abstract A060: Breast cancer-associated leukocyte DNA methylation profile in obese African-American women

Abstract Background: DNA methylation (DNAme) is a stable epigenetic mark leading to reduced gene expression. However, genome-wide DNAme profile is susceptible to disease. Therefore, specific genetic DNAme profiles could potentially serve as biomarkers associated with breast cancer (BC) and obesity as its comorbidity. Incidentally, BC-related mortality is higher in African-American women, causing a significant health disparity. In this study, we profiled obesity and breast cancer-related leukocyte DNAme in African-American women to explore methylation- associated biomarkers in these women. Methods: We used 10 African-American women with confirmed breast cancer diagnosis and 10 otherwise healthy African-American women with known Body Mass Index (BMI) > 30 (Obese). DNA was extracted from the buffy coat of peripheral blood using Qiagen DNA extraction kits. We used the next-generation sequencing technology to perform reduced presentation bisulfite sequencing (RRBS) using the Tecan Ovation RRBS kit. We sequenced the libraries on a NextSeq 550 at our Precision Medicine Unit. Single-end 75bp reads were generated and processed using Bismark and mapped against the GRCh38 human genome, and differentially methylated regions (DMR) were derived using MethylKit using a 1 kb window. Gene Ontology and Disease association studies were conducted using DAVID and relapsed-free survival in Kmplot. Additionally, we compared the gene sets with obese and normal DMRs that had previously been obtained similarly. Results: We found that 83% of the DMRs were in the promoter/upstream regions of the nearest genes, and 96% of DMRs were part of CpG islands, indicating potential regulatory functions of these regions. Gene ontology analysis revealed that the DMR-associated genes were also overrepresented in breast carcinoma, Type 2 Diabetes, Obesity, and Tobacco usage, according to the DisGeNET and GAD disease associations databases. Genes with DMRs in their upstream or promoter regions - include PRDM16, PTBP1, RAB1A (lower methylation in cancer with obesity), and Multiple ribosomal genes along with RRAF, XKR4 (higher methylation in cancer with obesity). We observed lower methylation profiles in multiple genes in samples with cancer, which were higher in obese samples without cancer.Conclusion: Our study suggests that a distinct peripheral DNA methylation profile is associated with minority women suffering from both cancer and obesity. Our data show that showed that breast cancer modulates leucocyte DNA methylation profile in obese individuals towards that of a more normal BMI, causing a partial reversal. This potential reversal is primarily in the upstream regions of the genes detected for methylation. The DMR genes in cancer with obesity are significantly associated with overall survival in breast cancer, thus indicating a potential link in understanding the crosstalk between obesity and cancer. Citation Format: Pranabananda Dutta, Yanyuan Wu, Jaydutt V. Duta. Breast cancer-associated leukocyte DNA methylation profile in obese African-American women [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A060.

Abstract B169: Diversifying cancer patient advocate voices to eliminate health disparities

Abstract Cancer patient advocates have become key members in clinical research teams and participating in decision committees at FDA, NCI, ASCO, among others. There is a low number of Latino patient advocates actively participating in the above roles lacking opportunities to share lived experiences and challenges of their communities. Being able to sit at the table where advocates can share key issues and possible solutions can help eliminate health disparities. Based on the need to increase Latinos participation as research advocates, a training program was developed. The Latino cancer patient advocate training program was design to increase knowledge and develop a community of diverse individuals who can seek opportunities to participate in research teams and decision-making committees. The training program included 15 individuals and 4 mentors who were cancer patients, survivors and caregivers and were Latinos or from Latino descent. The training included four virtual sessions, one in-person session, and attending the conference advancing the science of cancer in Latinos. Those chosen to participate received a full scholarship. The dissemination process through emails and social media included a flyer with the requirements, inclusion criteria, and a link to the application form. A total of 34 people applied, 20 were interviewed, and 15 were selected. The participants were from eleven different states and represented different types of cancer. A based questionnaire before the training, one after the training was completed by the participants. A questionnaire comparing their knowledge before and after two virtual sessions and the in-person training was completed by 93.3% participants. Self-rated knowledge scores ranged from 1 (not knowledgeable at all) to 5 (extremely knowledgeable). The average knowledge score across all questions was 2.9 (somewhat knowledgeable) before the training and 4.0 (moderately knowledgeable) after participating in the training. Participants indicated having the most knowledge about “Resources for your cancer type” (average score: 3.6 before and 4.2 after) and “Patient Advocates” (average score: 3.4 before and 4.1 after) and the least knowledge about “Opportunities and Scholarships available for Advocates” (average score: 2.1 before and 3.8 after), which had the largest increase in knowledge. In terms of satisfaction with the overall training program, all participants were very satisfied (85.7%) or satisfied (14.3%). Further, 71.4% of participants strongly agreed and 28.6% of participants agreed that they were interested in becoming a scientific/research advocate because of their participation in the training. Other outcomes after the training include participants being invited to be DoD reviewers, panelists in conferences, participation in important committees. Furthermore, participants communicate weekly with each other sharing opportunities and information. This training provided knowledge and the opportunity to feel represented as Latino patient advocate diversifying the voices of advocates. Citation Format: Barbara Segarra-Vazquez, Sandi Stanford, Susanne Schmidt. Diversifying cancer patient advocate voices to eliminate health disparities [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B169.

Abstract B056: Empowering underserved communities: The impact of the Sun Bus and Texas Tech on skin cancer awareness and prevention in “Sun City”

Abstract Purpose: Ultraviolet radiation is the primary cause of skin cancer.1,2 Other risk factors include fair skin, moles, family history, and history of sunburns.1,3 Photoprotective practices and regular skin examinations can help prevent skin cancer associated with ultraviolet radiation,5-8 underlining the importance of prevention and early detection. However, dermatological health disparities, such as limited access to dermatologists and inadequate awareness of sun protection practices, present significant challenges to effective prevention and early detection efforts. Recognizing and addressing these barriers is crucial, particularly amongst minoritized groups, who carry a higher burden of skin cancer morbidity and mortality.9 The Sun Bus, affiliated with the Colorado Melanoma Foundation, travels across the United States providing free skin cancer screenings and prevention education to reduce the incidence of skin cancer.1 In collaboration with the Sun Bus, Paul L. Foster School of Medicine and Myth Busters at Texas Tech University Health Sciences Center El Paso organized a bilingual skin cancer education and screening community event in El Paso, Texas. The main objectives were to debunk skin cancer myths prevalent in underserved communities and to strengthen prevention initiatives. Methods: Participants were administered optional surveys assessing their skin cancer knowledge and prevention behaviors before and after attending the session. Demographic data was collected, and pre-event and post-event knowledge were quantified using unpaired T-tests. Results: The event was attended by over 100 people. Over 80% of the event attendees were Hispanic. Among them, approximately one-third had only graduated high school, another third had completed college, and one-quarter held advanced degrees. The ages of participants ranged from 18 to over 75. Notably, 22% of respondents were uninsured. All survey respondents reported learning something new from the event. The performance from the pre-test to the post-test improved significantly by 7.04% (p=0.017). Additionally, attendees reported better knowledge about where to apply sunscreen and the importance of wearing sun-protective clothing. Conclusion: The Sun Bus Community Initiative proved to be an effective method for participants to learn about sun protection, skin cancer prevention and screening. This initiative could serve as a model to implement in other underserved communities to improve skin cancer awareness and prevention. Citation Format: Daniel Lovasz, Brian Kan, Hannah Riva, Shravya Kichena, Fabiola Ramirez, Whitney Shaffer, Julia Guido, Mariana Arajuo-Rincon, Jessica Chacon. Empowering underserved communities: The impact of the Sun Bus and Texas Tech on skin cancer awareness and prevention in “Sun City” [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B056.

Abstract A071: County-level racial and ethnic diversity index and cancer mortality in the U.S.

Abstract Background: The United States is experiencing a demographic trend of increasing racial and ethnic diversity. While persistent racial and ethnic disparities in cancer mortality are well documented, little is known about the impact of racial and ethnic diversity on cancer outcomes in the United States. Purpose: We examined associations between the U.S. county-level racial & ethnic diversity index and age-adjusted cancer mortality rates. We also assessed whether associations differed by geographic region, persistent poverty, and rurality. Methods: We used the U.S. Census Bureau’s 2020 Racial and Ethnic Diversity Index, which estimates the chance that two people chosen at random will be from different racial and ethnic groups. The diversity index was calculated at the county-level and categorized as follows: less than 35% (lowest), 35.0 to 44.9%, 45.0 to 54.9%, 55.0 to 64.9% and 65.0% or more (highest). We described county- level sociodemographic characteristics according to the diversity index categories. We calculated mean and standard errors of the county-level age-adjusted cancer mortality rates per 100,000 from 2016-2020 (overall and by site for the top four sites for cancer mortality) across the diversity index categories. We used multivariable linear regression models to examine associations between racial and ethnic diversity and cancer mortality, overall and by cancer site. We also assessed models stratified by geographic region (U.S. Census regions), persistent poverty and rurality. Results: Counties with more racial and ethnic diversity had a younger median age, a higher proportion of college graduates, and were less likely to be rural. Cancer mortality rates per 100,000 were lower in the most vs. least diverse counties, overall (144.7 vs. 164.6), and for lung (32.5 vs. 44.8), and colorectal cancer (13.0 vs. 15.6). In adjusted models, the highest vs. lowest racial and ethnic diversity was associated with a 7.25 decrease in overall cancer mortality rates (95% CI: -10.5 to -4.0), a 6.55 decrease in lung cancer mortality (95% CI: -8.0 to -5.1) and a 1.49 increase in breast cancer mortality (95% CI: 0.7 to 2.3). The diversity index was not associated with colorectal cancer mortality or pancreatic cancer mortality in adjusted models. Inverse associations of diversity index and overall cancer mortality were strongest in the South Census region (b=-13.0, 95% CI: -17.5 to -8.4), in non-persistent poverty counties (b=-9.0, 95% CI: -12.4 to -5.5), and in rural counties (b=-8.6, 95% CI: -13.2 to -4.1). Conclusions: Greater racial and ethnic diversity was associated with lower overall cancer mortality and lung cancer mortality rates, although it was associated with significantly higher breast cancer mortality rates. Findings help elucidate whether and how social factors may differentially impact subgroups of the population to influence cancer mortality. This study addresses an urgent need to explore contextual factors that may shape racial and ethnic disparities at the population level. Citation Format: Kelly A. Hirko, Breanna Greteman, Sabrina Ford, Sarah H. Nash. County-level racial and ethnic diversity index and cancer mortality in the U.S. [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A071.

Abstract A048: Association between ambient particulate matter and colorectal cancer incidence: The Multiethnic Cohort Study

Abstract Background: Growing evidence suggests that air pollution may be a risk factor for colorectal cancer (CRC). We examined the association between ambient particulate matter (PM) exposure and CRC risk within the Multiethnic Cohort Study (MEC), representing the first study to include a large sample of racial and ethnic minoritized populations. Methods: The MEC is a prospective study that recruited, from 1993 through 1996, men and women ages 45-75 years largely from five racial and ethnic groups (African American, Japanese American, Latino, Native Hawaiian, and Non-Hispanic White) living in Hawai‘i and California. This study included 98,675 California MEC participants, residing predominately in Los Angeles County. Satellite-based PM2.5 (PM with an aerodynamic diameter <2.5μm) exposures were estimated from a published spatiotemporal model. Kriging interpolation was used to estimate PM10 (PM <10μm) exposures using routine air monitoring data from the US Environmental Protection Agency. Time-varying PM exposures were assessed from time of recruitment through 12/31/2018. Incident invasive CRC cases were identified via linkage with the California Cancer Registry (n=3,217). Cox proportional hazards models were used to examine the association between PM and CRC risk using age as the time metric, with strata defined by age at cohort entry and race and ethnicity, and adjusting for demographic and lifestyle factors. Heterogeneity of the PM-CRC association was assessed by sex, race and ethnicity, and CRC subsite (right colon, left colon, rectum). Results: Risk of CRC increased with PM2.5 (per 10μg/m3 hazard ratio [HR] 1.13, 95% confidence interval [CI] 0.96-1.33) with a larger HR observed among females (HR 1.29, 95% CI 1.03-1.62) than males (HR 0.96, 95% CI 0.76-1.22) (Pheterogeneity=0.24). CRC risk was positively associated with PM2.5 across race and ethnicity (except for African American participants) with the largest HR observed among Latino participants (HR 1.47, 95% CI 1.03-2.08) (Pheterogeneity=0.20). There was no statistically significant heterogeneity of PM2.5 effect by tumor subsite (Pheterogeneity=0.07); although larger HRs were seen for left colon (HR 1.52, 95% CI 1.08- 2.14) and rectal cancers (HR 1.54, 95% CI 1.05-2.25) than right colon cancers (HR 1.09, 95% CI 0.88-1.35). PM10 was not associated with CRC risk (per 10 μg/m3; HR 1.02, 95% CI 0.93-1.22) with no evidence of heterogeneity in associations by sex or race and ethnicity (respective Pheterogeneity 0.75, 0.44). Although HRs for PM10 appeared to differ by CRC subsite (Pheterogeneity=0.03), the 95% CI of these HRs included the null (right HR 0.95, 95% CI 0.84-1.06; left HR 1.13, 95% CI 0.95-1.35; rectal HR 1.18, 95% CI 0.97-1.43). Conclusions: Preliminary findings suggest that PM2.5 exposure is associated with CRC risk with larger associations in females and, possibly, for left colon and rectal cancer. Additional studies are needed to confirm these findings and evaluate the potential biological pathways underlying these associations. Citation Format: Ugonna Ihenacho, Chiuchen Tseng, Jun Wu, Scott Fruin, Timothy V. Larson, Salma Shariff-Marco, Loïc Le Marchand, Daniel O. Stram, Lynne R. Wilkens, Christopher A. Haiman, Beate Ritz, Iona Cheng, Anna H. Wu. Association between ambient particulate matter and colorectal cancer incidence: The Multiethnic Cohort Study [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A048.

Abstract A032: Disparities in molecular subtypes of acute lymphoblastic leukemia incidence by age, race/ethnicity, and sex in the United States

Abstract Acute lymphoblastic leukemia (ALL) is the most common cancer in children and a heterogeneous disease comprising several molecular subtypes. The increased risks of ALL in individuals assigned male at birth and in those of Hispanic/Latino ethnicity compared to non-Hispanic White individuals are well known. Less well-established are potential differences in the prevalence of specific molecular subtypes of ALL by sex or racial/ethnic groups. Here, we provide updates on incidence patterns for lymphoid leukemias reported by cancer registries across the United States, leveraging recent data on molecular subtypes of ALL. We obtained data from the North American Association of Central Cancer Registry (NAACCR) for United States-specific incidence cases from 2000 through 2020. Diagnoses and leukemia subtype reporting, limited to ALL only, was based on the International Classification of Diseases for Oncology, Third Edition (ICD-O-3). Age-adjusted (2000 US Standard) incidence rates (AAIR) were calculated using SEER*Stat (version 8.4.3). Incidence rate ratios (IRR) were calculated to assess patterns in leukemia incidence by sex and by race/ethnicity across three age groups: 0- 14 (children), 15-39 (adolescents and young adults, AYA) and 40+ (older adults) years. Information on selected molecular subtypes of ALL was available for cases diagnoses 2010 onwards, from ICD-0-3 histology codes that were determined by genetics and/or immunophenotyping. Overall and in each age group compared to non-Hispanic Whites (NHWs), Blacks/African- Americans (B/AAs) had significantly lower AAIRs for ALL whereas Hispanic/Latinos (H/Ls) had significantly higher AAIRs, in particular for B-cell ALL. Analysis by molecular subtypes revealed that overall, H/Ls were at higher risk for BCR::ABL1 translocation than NHWs, with the greatest difference seen in AYAs in which H/Ls had a 2.5-fold (95% CI=2.08-3.00) higher risk of BCR::ABL1. In children, H/Ls had significantly higher incidences of several ALL subtypes compared with NHWs, including BCR::ABL1 (IRR=1.5; 95% CI=1.13-1.98) and TCF3::PBX1 (IRR=2.0; 95% CI=1.43-2.79) but also ETV6::RUNX1 and high hyperdiploidy (both IRR=1.27; 95% CI=1.12-1.43). Males were at significantly higher risk than females for ALL and its subtypes across all ages combined and stratified age categories. In particular, males had a 2.5- fold increased risk of precursor T-cell lymphoblastic leukemia compared to females (IRR=2.5; 95% CI=2.28-2.73) in all ages combined, and a 3.0-fold increased risk in both AYAs (95% CI=2.59-3.46) and older adults (95% CI=2.54-3.54). Among molecular subtypes, the highest IRR was observed for BCR::ABL1 in AYAs wherein males were at 50% increased risk (IRR=1.5; 95% CI=1.27-1.76). In addition to confirming the previously reported disparities in ALL incidence by race/ethnicity and by sex, we report an increased incidence of particular molecular subtypes of ALL in Hispanics/Latinos and in males. Studies to investigate potential genetic and environmental risk factors underlying these disparities are warranted. Citation Format: Anmol A. Pardeshi, Juanita Elizabeth Quino, Nicholas Acuna, Talar Habeshian, Raymond Hughley, Isabella Ortiz, Michelle Tran, Ying Yan, Cindy Zamora, Joseph l. Wiemels, Kai-Ya Tsai, Lihua Liu, Adam J de Smith. Disparities in molecular subtypes of acute lymphoblastic leukemia incidence by age, race/ethnicity, and sex in the United States [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A032.

Abstract C154: Clinical, genomic, and socioeconomic factors underlying low survival rates from colorectal cancer in African American patients

Abstract Background: Colorectal cancer (CRC) patients of African ancestry (AFR) have higher incidence, higher mortality, and shorter overall survival (OS) than patients of non-African ancestry (non-AFR) in the United States. This disparity is likely due to a combination of clinical, genomic, and socioeconomic factors. We investigated real-world data of patients from a single tertiary cancer center to delineate the contribution of each of those variables. Methods: We analyzed data from 3,995 CRC patients, including 247 AFR and 3,748 non-AFR patients, diagnosed after 2014 and treated at Memorial Sloan Kettering Cancer Center. Every patient had a specimen sequenced with MSK-IMPACT, a targeted DNA sequencing assay that identifies genomic alterations in 341-505 genes. Genetic ancestry was determined using previously published methods by our group. Clinical annotations included sex, age at diagnosis (Dx), stage at Dx, and tumor location. Billing records were used to identify the type of insurance per patient and estimate their Yost Index (YI), a location-dependent socioeconomic status (SES) percentile score based on household incomes, house values, rent, poverty, education, and employment statistics. A multivariate cox proportional hazards model was used to assess the association between clinical variables (stage at Dx, age at Dx, sex, primary tumor location), genomic features (MSI status, BRAF, APC, SMAD4 alterations, chromosome 20Q amplifications), SES (YI) and OS. Propensity score matching (PSM) was performed using all features included in the multivariate model to assess outcome differences after matching for clinical, genomic, and socioeconomic variables. OS was measured in months from time of Dx to last follow-up and compared using the log-rank test. Results: AFR patients had worse OS compared to non-AFR patients (median OS: AFR, 44.9 vs. non-AFR, 64.3, p<0.001). AFR patients were younger at Dx (median 53 vs. 57 yo, p<0.001), had higher rates of right-sided tumors (41.1% vs. 30.2%, p<0.001), and less often had microsatellite unstable (MSI) tumors (5.26% vs 10.0%, p=0.014). Among microsatellite stable cases, AFR patients had a higher frequency of KRAS (57.1% vs. 44.7%, p=0.004) and a lower frequency of BRAF mutations (4.3% vs. 7.7%, p=0.069). Medicaid was more frequent among AFR patients (10.12% vs. 4.87%, p<0.001). AFR patients had lower SES (median YI 42 vs. 17, p<0.001). In a multivariate model accounting for clinical, genomic and socioeconomic features, AFR ancestry remained associated with worse outcomes (HR: 1.35, p = 0.007). AFR patients also had significantly shorter OS than the set of non-AFR patients matched for clinical, genomic, and socioeconomic features (5-yr OS was 31.6% for AFR vs 45.7% for non-AFR, log-rank p-value = 0.014). Conclusions: Colorectal cancer patients of AFR ancestry had significantly shorter OS than patients of other ancestries after accounting for basic clinical, genomic, and socioeconomic variables. Further research is needed in order to understand the causes of this disparity. Citation Format: Sharafudeen D. Abubakar, Henry Walch, Xuechun Bai, Tejiri Agbamu, Michele Waters, Kanika Arora, Farheen Shah, Christopher Fong, Justin Jee, Hannah Williams, Michael F Berger, Karuna Ganesh, Julio Garcia- Aguilar, Nikolaus Schultz, Rona Yaeger, Walid K Chatila, Francisco Sanchez-Vega. Clinical, genomic, and socioeconomic factors underlying low survival rates from colorectal cancer in African American patients [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C154.

Abstract B067: A mixed-methods health services analysis of disparities and social vulnerabilities in childhood cancer survivors’ long-term follow-up care

Abstract Pediatric cancer affects >15,000 US children annually. Treatment advances have led to an increase in those surviving the disease, and these patients must be managed to control their long-term comorbidities. Unfortunately, a majority are nonadherent to post-treatment care guidelines and become lost to follow-up. This is especially true for those from underserved backgrounds, including survivors who are Black and Latine. To help understand this disparity, we studied the organization and delivery of pediatric cancer survivorship care at an urban comprehensive cancer center. Research included: 1) a qualitative study exploring healthcare barriers and facilitators of survivors’ adherence to long-term follow-up care, as determined by N=31 key informants (pediatric oncology care providers, administrators), and; 2) a retrospective cohort study (2007- 2020) among N>350 survivors (10% Black, 28% Latine, 12% Asian; 47% from vulnerable neighborhoods) assessing social determinants of health (SDoH) and its cofactors, adjusted for vital status. Interviews were recorded, transcribed, and thematically analyzed using software (K>.70). Three major themes emerged in survivors’ adherence: 1) healthcare system-level influences (69%), SDoH (25%), and intra/interpersonal factors (16%). At the system-level, informants noted opportunities to strengthen adherence, especially for survivors from underserved backgrounds, including the provision of greater social support (14%), easing appointment scheduling (11%), offering high-quality ambulatory and specialty care within the system upon entering young adulthood (12%), and cultural competency training for staff (6%). Among SDoH, informants noted transportation and geographic challenges in accessing the healthcare system (25%), insurance coverage for follow-up care (17%), and strengthening trust with marginalized communities (17%). For intra/interpersonal factors, time- and age-related changes in survivors’ medical needs were acknowledged as barriers to be overcome (28%), along with providing greater patient education (11%) and heightened salience of follow-up care (17%). Conversely, the provider-patient relationship was noted as a strength in promoting adherence (23%). Retrospective cohort results revealed that survivors’ attendance at dedicated clinics was suboptimal (52% >= 2 years off-therapy), as were rates of system-wide ambulatory care encounters 3+ and 5+ years post-therapy. At the bivariate level, non-Hispanic Black survivors (68%), adolescents (58%), and those with CNS tumors (81%) had the lowest likelihood of survivorship clinic attendance (p<.05)–underscoring qualitative findings on SDoH. Area-level SDoH indices were unrelated to the cohort’s adherence, highlighting qualitative findings on intra/interpersonal barriers and facilitators. These data lend insights into transformations possible within the organization and delivery of healthcare to young survivors, especially those from underrepresented backgrounds, including greater attention to SDoH and strengthening cultural competence among health system employees. Citation Format: Marcelo Sleiman Jr, Tara Suntum, Nina Kadan-Lottick, Brianna Miller, Mary R Yockel, Arnold Potosky, Chiranjeev Dash, Adil Alaoui, Burton Appel, Ken Tercyak. A mixed-methods health services analysis of disparities and social vulnerabilities in childhood cancer survivors’ long-term follow-up care [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B067.

Abstract A009: Determinants of increased generalized self-efficacy among Hispanic/Latino colorectal cancer patients participating in a Cancer Moonshot Study

Abstract Background: Colorectal cancer (CRC) accounts for a greater proportion of all cancer deaths among Hispanic/Latino/a/x (H/L) individuals compared to Non-Hispanic White (NHW) subjects. However, the tumor landscape and key determinants of outcomes for CRC among H/L patients remain understudied. Methods: As a Cancer Moonshot initiative, we launched the “Enfrentando el Cancer en Comunidad” (ENLACE) study, which engages H/L CRC patients to characterize their germline genetics and tumor genomic landscape, and to collect data to identify determinants of participation in genetics/genomics research and cancer outcomes. H/L CRC patients >=18 years of age are being recruited from two healthcare facilities: a safety-net hospital, Los Angeles General Medical Center (LA Gen), and a university medical center, USC Norris Comprehensive Cancer Center (Norris). An H/L bilingual team administered surveys to assess patient demographics, acculturation level, Latino values, health literacy, numeracy, CRC risk factors, genetics knowledge (Knowgene scale), and generalized self-efficacy (GSE) upon recruitment for the study, and after return-of-results (ROR) of somatic and germline testing. Results: 165 H/L CRC patients have joined the ENLACE study, with 105 completing baseline surveys (56 male, median age 53 (IQR = 45-60)), and 39 with finalized ROR. Most of the participants self-identified as White (58.1%), were Mexico-born (52.4%), and married (50%). Patients from Norris (n = 33) were more likely to be US-born (55%), college graduates (21%), and annually earn at least $100,000 (69%) while employed full-time (45%) than LA Gen patients (all p-values <0.01). Additionally, Norris patients had higher numeracy and health literacy scores at baseline than LA Gen (p = 0.006 & p = 0.042, respectively). LA Gen patients (n = 72) showed higher scores for familism, respect, traditional gender roles, material success, and mainstream values in the Latino-American cultural values scale (all p-values < 0.05). Higher levels of GSE across all patients were associated with increased numeracy (p = 0.014). LA Gen participants with a higher score for GSE, had on average, higher subscores for material success (p = 0.011), competition and personal achievements (p = 0.07), and mainstream values (p = 0.051), and decreased uncertainties about genetic testing (p = 0.05). A multivariable logistic regression model adjusted for treatment facility, acculturation, age, gender, and income reported that a 1 unit increase in numeracy was statistically significantly associated with 1.62 times the odds of having a greater than the median GSE score (95% CI: 1.09-2.39, p = 0.016). After ROR, a decrease in the number of times participant selected “Don’t know” in the KnowGene scale was reported (p <0.001). Conclusion: We report differences in baseline characteristics for ENLACE participants across healthcare facilities and determinants of generalized self-efficacy. These findings can help inform future interventions to improve self-efficacy and optimize engagement of H/L patients navigating CRC treatment. Citation Format: Joel Sanchez Mendez, Carmen Chavez, Lucia Enriquez, Julie O Culver, Charité N Ricker, Natalia Gutierrez, Sandra Algaze, Lourdes Baezconde-Garbanati, John D. Carpten, Heinz-Josef Lenz, Mariana C. Stern. Determinants of increased generalized self-efficacy among Hispanic/Latino colorectal cancer patients participating in a Cancer Moonshot Study [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A009.

Abstract A021: Development of cross-ancestry polygenic risk. scores for breast cancer in women of African ancestry

Abstract Introduction: Polygenic risk scores (PRSs) predict breast cancer (BC) risk and have shown utility for screening in European ancestry women (EUR). However, PRSs developed for non-European ancestry, particularly African American (AA) women, have limited predictive accuracy. Methods: We analyzed data from 17,454 BC cases and 19,093 controls in the African American Breast Cancer Genetics (AABCG) consortium, split into training (70%), tuning (10%), and testing (20%) sets. Genome-wide association analyses for overall BC, ER-positive BC, ER- negative BC and triple-negative BC (TNBC) were performed in the training dataset, controlling for age, genotyping platform, and the top 10 principal components. We built single-ancestry PRS models using forward stepwise selection (FSS), PRSice-2, PLINK C+T, Lassosum2, and LDpred2-auto. These were combined with published EUR 313-SNP models (330-SNP for TNBC) in the tuning set to obtain cross-ancestry models. Genome-wide cross-ancestry PRS methods, including CT-SLEB and PRScsx, were also used. We created an ensemble model by combining different PRS models across subtypes using ensemble-based approaches. All developed PRS models were then evaluated in the independent testing set. Additional validation was performed using the All of Us (AoU) study with 834 BC cases and 29,122 controls from the AA population. Results: The observed-scale SNP-based heritability was estimated at 0.29 (SE: 0.12) for overall BC risk, 0.43 (SE: 0.18) for ER-positive BC, 0.44 (SE: 0.24) for ER-negative BC, and 1.13 (SE: 0.40) for TNBC. The best models showed good discriminating capacity: ensemble-based models for overall (AUC=0.626) and ER-positive BC (AUC=0.626), and combined cross-subtype and cross-ancestry FSS models for ER-negative (AUC=0.647) and TNBC (AUC=0.654). The odds ratio per standard deviation was 1.63 (95% CI: 1.55, 1.71) for the ensemble-based PRS of overall BC risk, with an estimated life risk of 28% for the top 1%. The cross-ancestry model using CT-SLEB combined with the EUR 313-SNP model was validated (AUC=0.61) among AA women in the AoU study. Conclusion: We developed PRSs with improved discriminating ability for BC risk in women with African ancestry. Cross- ancestry and subtype learning enhanced model performance. These findings indicate common variation has a larger role in BC in AA women than previously reported, warranting further validation in external AA populations and clinical evaluation. Citation Format: James L. Li, Haoyu Zhang, Julian C McClellan, Guimin Gao, Kevin Wang, Julie R. Palmer, Olufunmilayo I. Olopade, Christopher A. Haiman, Dezheng Huo. Development of cross-ancestry polygenic risk. scores for breast cancer in women of African ancestry [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A021.

Abstract C024: Evaluation of PI3K/AKT/mTOR pathway signaling as a prognostic indicator in Hispanic Mexican women with breast cancer

Abstract Breast cancer (BC) is among the most commonly diagnosed cancer in women and a leading cause of cancer death worldwide. Hispanic/Latina women represent a heterogeneous group with diverse genetic backgrounds, including varying proportions of Native American, European, African and to a lesser extent Asian ancestry. In the US, Hispanic and African American women have lower BC incidence overall yet higher incidence of triple negative breast cancer (TNBC). Furthermore, African American and Hispanic women tend to present with more aggressive disease, at younger ages and worse survival compared to women of European ancestry. These disparities have been attributed to biologic and non-biologic socioeconomic factors. Genomic analyses of Hispanic Mexican (HM) women have revealed specific genetic signatures distinct from those of non-Hispanic women. These variations include AKT kinase mutations activating PI3K/AKT/mTOR signaling pathway and PI3KCA mutations which could potentially benefit from targeted therapies. 4EBP1 phosphorylation by mTORC1 is generally considered a marker of activated mTOR signaling and high levels in tumors associate with worse outcomes in different cancers. To evaluate clinical significance of PI3KCA expression and PI3K/AKT/mTOR signaling, we performed immunohistochemical (IHC) analyses of tissue microarrays (TMA) including 272 BC patient samples from HM women. Protein expression of PI3KCA and p4EBP1 were evaluated quantitatively by receiver operator characteristics (ROC) curves based on area under the curve (AUC) as well as sensibility and specificity. p4EBP1 levels were associated with clinicopathological characteristics. Chi-squared and Fisher’s Exact tests showed higher p4EBP1 expression correlated with estrogen (P=0.001) and progesterone receptor negative BC (P=0.003), TNBC (P<0.001), tumor size (P<0.090), and advanced stage (P<0.001). PI3KCA expression was positively correlated with 4EBP1 expression (P=0.044) as shown by Mann Whitney U tests; but PI3KCA lacked prognostic value after screening through ROC curves. However, uni- and multi-variate Cox regression analyses did show that increased 4EBP1 expression correlates with worse OS. Overall, our study indicates that higher p4EBP1 expression is an independent prognostic factor of worse OS in BC patients. The activation of 4EBP1 may result from several upstream oncogenic alterations or mutations, representing a potential therapeutic target and biomarker. Further research is necessary to better define biological differences in Hispanic women to advance understanding and targeting of health disparities. [Funded by California Breast Cancer Research Program Idea Award B27IB3869, JCCC Breast Cancer Award, Hickey Family Foundation, NCI U54 CA143930, Team Research Grant, UCLA TDG, CIRM DISC2-14166]. Citation Format: Mario Morales Martinez, Giovanny Soca-Chafre, Altagracias Maldonado-Valenzuela, Clara M Rivera-Pazos, Gabriela Antonio-Andres, Mayra Montecillo-Aguado, Georgina Rocha-Lopez, Berenice Alcala-Mota-Velazco, Anel Gomez-Garcia, Madhuri Wadehra1, Richard J Pietras, Sergio Gutierrez-Castro, Sara Huerta-Yepez, Diana Marquez-Garban. Evaluation of PI3K/AKT/mTOR pathway signaling as a prognostic indicator in Hispanic Mexican women with breast cancer [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C024.

Abstract A091: Beliefs and behaviors regarding non-cigarette tobacco use cessation care differ between providers at substance use treatment centers and community health centers serving rural and/or medically underserved areas of Texas

Abstract Purpose: Cancer mortality rates are higher in rural versus urban areas of the US, partly due to elevated tobacco use (including non-cigarette tobacco products (NCTPs); e.g., dip, snuff, vapes). Clinical practice guidelines call for tobacco use screening and brief intervention at every patient contact. Limited literature examines actual practices with respect to NCTP use in healthcare centers in rural and/or medically underserved areas (MUAs). This study examines if providers at substance use treatment centers (SUTCs) and community health centers (CHCs; e.g., Federally Qualified Health Centers) in such areas of Texas view NCTP cessation counseling as an important part of their job and if they use the 5As (Ask, Advise, Assess, Assist, Arrange) and motivational interventions to address their patients’ NCTP use. Methods: Providers from 21 healthcare centers (12 SUTCs, 9 CHCs) that had been solicited to later receive resources to improve their tobacco cessation care responded to face-valid survey items about their tobacco use screening and intervention delivery over the last month, along with their view on whether NCTP cessation counseling is an important part of their job. In total, 347 providers from SUTCs (n=174) and CHCs (n=173) serving 126 of Texas’ 254 counties responded. Linear mixed models and generalized linear mixed models were used to assess the differences between SUTCs and CHCs for continuous and binary variables, respectively. Results: Only 52% of providers agreed that NCTP cessation counseling is an important part of their job, with a significantly greater percentage (p=0.0023) agreeing at CHCs (63%) than at SUTCs (40%). Providers Asked 62% of their patients whether they used NCTPs. Of patients who endorsed use (20%), providers Advised 58% to quit and Assessed 53% about their interest in quitting. However, providers only Assisted 34% of use-endorsing patients in making a quit attempt and only Arranged follow-up for 23% of them. A significantly greater percentage (p=0.0025) of those patients were Advised to quit at CHCs (72%) than at SUTCs (44%). Providers delivered brief motivational interventions to 74% of patients who were not ready to quit, with significantly greater percentages advising patients to consider quitting in the future (p=0.0365) and telling patients they would revisit the topic at the next visit (p=0.0264) at CHCs (63% and 37%, respectively) than at SUTCs (45% and 24%, respectively). However, providers encouraged only 39% of use-endorsing patients to stop NCTP use completely, with a significantly greater percentage (p=0.0010) doing so at CHCs (50%) than at SUTCs (28%). Conclusion: Providers surveyed at healthcare centers in rural and/or MUAs of Texas were more likely to deliver evidence-based NCTP cessation care at CHCs than at SUTCs. Patients at both CHCs and SUTCs would benefit from their providers placing greater value on NCTP cessation care and more consistently delivering such care per guidelines. These data will inform healthcare centers’ implementation of best practices in treating their patients’ NCTP use. Citation Format: Brian J. Carter, Maggie Britton, Tzuan A. Chen, Isabel Martinez Leal, Ammar D. Siddiqi, Teresa Williams, Kathleen Casey, Hector Sanchez, Sriya Kakarla, Lorraine R. Reitzel. Beliefs and behaviors regarding non-cigarette tobacco use cessation care differ between providers at substance use treatment centers and community health centers serving rural and/or medically underserved areas of Texas [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A091.

Abstract C063: Using a disparities dashboard to identify racial/ethnic differences in breast cancer treatment: Implications for improving cancer care delivery

Abstract Purpose: The use of a cancer dashboard to assess and inform real time assessments of the timing of surgery and systemic treatment by race/ethnicity may be used to address delays in cancer treatment. Yet, the utility of cancer dashboards in cancer settings are unclear as electronic medical record (EMR) stage data are unstructured. We investigated whether a cancer disparities dashboard can be used to assess racial/ethnic differences in the first line of breast cancer treatment and timeliness of breast cancer surgery. Methods: A disparities cancer dashboard was built using data from the tumor registry and the EMR’s Data Warehouse. Key fields assessing patient race/ethnicity, cancer stage, receptor status, surgery type, treatments received and dates of surgery were collected. This retrospective analysis included women diagnosed with a new primary breast cancer who underwent definitive surgery at an urban Hospital (2010-2020). We defined delays as >8 weeks to treatment initiation, and delay to breast surgery as > 6 weeks from diagnosis. Chi-square and t tests were used to assess independent variables (e.g., stage, age) by race/ethnicity. Patient-level multivariable logistic regression was used to evaluate the association between race/ethnicity and delays to initiation of first treatment and surgical delays. Results: Of 8,403 women identified (46.5% non-Hispanic White, 17.7% Black, 16.9% Hispanic), 66% had stage I cancer, 72% had estrogen receptor cancer. 18.6% of the sample had delays to first treatment modality and 42.6% experienced delays to breast surgery. After adjusting for stage, age and receptor status Black patients compared to non-Hispanic White patients had the greatest likelihood of delayed first treatment (OR: 2.09; 95% CI:1.7-2.5) or surgery delays (OR:1.76; 95% CI:1.5-2.0). With regards to clinical/sociodemographic factors younger patients (22-39 vs. 40-64; p<0.001), mastectomy surgery type (vs lumpectomy; p=0.031), higher stage (stage 3 vs.1; p<0.0001), HER2 + and TNBC receptor status (vs. ER+; p<0.0001) were more likely to experience surgery delays. Conclusions: Given persistent breast cancer survival disparities, health IT strategies are needed to help reduce disparities. A disparities dashboard can be used to assess differences in timeliness of care when treatment can still affect outcomes. These data can be used to inform quality initiatives to improve cancer care delivery for at-risk patient populations who experience worse cancer outcomes. Citation Format: Megan Edmonds, Parul Agarwal, Tara Balija, Cardinale Smith, Nina Bickell. Using a disparities dashboard to identify racial/ethnic differences in breast cancer treatment: Implications for improving cancer care delivery [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C063.

Abstract B096: Patient, Provider, and Advocate Perspectives on Factors that Impact Participation of Black Women in Breast Cancer Clinical Trials

Abstract Background: Black women are more likely to present with advanced stage disease and to die following a breast cancer (BC) diagnosis compared with women from other racial and ethnic groups. This persistent health inequity is in part driven by underrepresentation in clinical trials (CTs), as well as structural and social drivers of health. Multi-level factors impact patients’ decision to enroll on a cancer CT. Objective: The goal of the FOR ME (Fostering Opportunities in Research through Messaging and Education) study is to develop, optimize, and test a narrative web-based video intervention for Black women diagnosed with BC to promote shared decision making and CT participation. Here, we report findings from the development phase, wherein we engaged Black women with BC, oncologists and CT office staff, and cancer advocates. Our objective was to identify cross-cutting and unique themes concerning barriers and motivating factors to CT participation, intervention priorities, and to understand lived experiences to enhance authenticity and to inform video content. Methods: Guided by community engaged research approaches, we used multiple qualitative methods, including story circles and 1:1 interviews. We used thematic analysis and inductive and deductive coding approaches. Data analysis for each group followed the same approach: we annotated a subset of transcripts, compiled the annotations into a preliminary codebook, and conducted inter-coder reliability to improve quality and refine the codebook. Finally, we used Dedoose to analyze quotations and code co-occurrences, application frequencies, and relationships. We examined cross-cutting and unique themes during data collection and analysis. Results: In total, 38 Black women with BC participated in interviews and story circles, ranging in age from 27-75 years (M=59, SD =12); about 27% were currently receiving BC treatment and 27% had prior CT participation. Oncologists (n=16) and CT office staff (n=4) reported having on average 11.6 and 9.5 years of CT experience, respectively). Finally, 15 cancer advocates completed interviews, of whom 73% identified as Black women; 87% reported that the organization they were involved with connected patients to or provided education about CTs. Several cross-cutting themes were identified, including: 1) Acknowledgement of time, financial, and logistical burdens of CT participation; 2) The impact that current and historical racism, discrimination and mistreatment has had on CT enrollment for Black BC patients; 3) A lack of accessible CT information poses significant challenges for health literacy; and 4) Positive provider relationships and communication are important facilitators to CT participation. Conclusion: To promote health equity and participation in CTs among Black women with BC, interventions should consider multiple perspectives and prioritize addressing culturally sensitive patient-provider communication, shared decision-making, and patient empowerment. The information we learned will inform the development of a culturally tailored decision aid video. Citation Format: Leslie R. Carnahan, Eliza B. Cohn, Tigist Mersha, Neha Hippalgaonkar, Ryan Nguyen, Kauthar Salum, Ana Williams Waite, Christen Sandoval, Lolita Coleman, Beulah Brent, Paris Thomas, Paramjeet Khosla, Kent F. Hoskins, Vida Henderson. Patient, Provider, and Advocate Perspectives on Factors that Impact Participation of Black Women in Breast Cancer Clinical Trials [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B096.

Abstract A036: Hair relaxers use and breast cancer risk by tumor estrogen receptor status: Results from the Ghana Breast Health study

Abstract Background: Hair relaxer use is highly prevalent among women of African descent world-wide and in previous analyses within the Ghana Breast Health Study (GBHS) ever use was associated with a 60% elevated risk of breast cancer. Subsequent studies in the GBHS showed selected alterations in estrogen metabolites with hair relaxer use among controls, suggesting a possible hormonal mechanism may underlie the relation of hair relaxers to breast cancer risk. We investigated if the association between relaxer use and breast cancer risk differed by tumor estrogen-receptor (ER) status and hypothesized ever-users would be at a higher risk of ER+ tumors. Methods: The GBHS is a population-based case-control study conducted between 2013– 2015 in Accra and Kumasi of 1,071 cases with pathologically confirmed invasive breast cancer and 2,106 controls, aged 18-74 years. A standardized interview-based questionnaire collected information on currency and duration of use of hair relaxers and whether products used were lye or non-lye formulations. ER status was available for 915 cases, determined using either mRNA expression data from nCounter® Breast Cancer 360™ Panel (65% of 915 cases) or immunohistochemistry. We used multivariable multinomial logistic regression models to estimate odds ratios (OR) with 95% confidence intervals (CI) for ER+ vs. ER- breast cancers. Models were adjusted for age, hospital site, education, body size, age at menarche, parity, age at first birth, median breastfeeding months/child, menopausal status. To determine if risk related to exposure to relaxers differed by ER status, we used logistic regression analyses with ER+ tumors as the reference and calculated heterogeneity p-values (p-het). Results: The majority of women reported ever use of relaxers (96% of cases and 94% of controls). Of the 1,071 cases included in analyses, 422 (44%) were ER+, 438 (41%) ER-, and 156 (15%) unknown for ER. Elevated risk did not differ by ER status for ever compared to never use (OR ER+ =1.67, 95% CI [0.95–2.93]; OR ER - =1.59, 95% CI [0.92–2.76], p-het=0.90). Risks were highest among former users (OR ER+ =2.19, 95% CI [1.21–3.95]; OR ER- =2.21, 95% CI [1.24–3.93], p-het=0.98. Additional analyses showed elevated risk for those with long durations of use, and those who predominantly used non-lye products, but associations did not differ according to ER tumor status. Conclusion: Our analysis of relaxer use in Ghanaian women showed elevated breast cancer risk, particularly for former, long-term users of non-lye formulations, irrespective of tumor ER status. Additional analyses by tumor and other characteristics related to biologically aggressive tumor types needed to determine if associations differ beyond ER consistent with disparities seen in African ancestry women. Further, future research is warranted regarding specific products used that may provide insights into hormonal and non-hormonal mechanisms underlying observed associations. Citation Format: Kaitlin E. White, Quiera Booker, Nicholas Titiloye, Lawrence Edusei, Louise Brinton, Beatrice Wiafe, Ernest Adjei, Jonine Figueroa, On behalf of the Ghana Breast Health Study Team. Hair relaxers use and breast cancer risk by tumor estrogen receptor status: Results from the Ghana Breast Health study [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A036.

Abstract B141 Self-reported distress in multiple myeloma patients at first consultation at a transplant referral center

Abstract The National Comprehensive Cancer Network (NCCN) recommends screening all cancer patients for distress to facilitate psychosocial support and referrals. This distress is associated with treatment delays and other obstacles that may affect patient outcomes. The prevalence of distress in patients with multiple myeloma (MM) and its variation among underrepresented minorities and vulnerable groups is unknown. We hypothesized that patients with advanced disease, racial minorities, and vulnerable individuals would report higher distress levels. New patients with MM seen between 1/1/2015-12/31/2022 at a tertiary medical center were identified. All patients receive the NCCN Distress Thermometer (DT) survey for completion at initial consultation as standard of care. Baseline characteristics of patients who completed the survey were compared with those of patients who did not. Among those with survey data, DT score was categorized as <4 (low), 4–6 (moderate), and >6 (high). DT score was analyzed by sociodemographic and disease-related factors. The 2020 Social Vulnerability Index (SVI) at the county level was calculated using Zip codes and categorized as less vulnerable (score <50) or more vulnerable (>=50). Of 1,011 new MM patient consultations, 683 patients had an available DT survey at initial consultation. In patients without the survey (N=328), a higher proportion was older than 75 years (21% vs 16% P=0.04), non-Hispanic Black (NHB) [22% vs. 9%, P<0.01], and with more advanced disease (ISS III 20% vs 14%, P<0.01). There was lower autologous stem cell transplant utilization in the group with missing survey data (71% vs 79%, P<0.01). Among those with DT survey, younger age, female sex, advanced stage, and shorter time from diagnosis to consult was associated with higher distress. In patients with DT survey data and SVI (N=683), the mean SVI was 0.37 (std dev 0.31) and 166 (28%) had more vulnerability. Younger age and NHB race were associated with more vulnerability. The more vulnerable group also had a shorter time from diagnosis to consult (1.2 vs 1.8 months, P<0.01). In the more vulnerable group, high DT score was seen with younger age and NHB race. There was no difference in transplant utilization by SVI group. No significant differences were found in the proportion of patients reporting concerns for physical, practical, emotional, social concerns by vulnerability. In this tertiary referral center study, we observed the greatest disparity by the completion of the NCCN DT survey highlighting a missed opportunity to identify individuals who may benefit from additional services. Among those who completed the survey, patient-reported distress was influenced by age, sex, and MM stage. Younger age was associated with more vulnerability. This may be due to minority status as a theme in the SVI calculator and the known association of younger age at MM onset in NHB individuals. Next steps including an adjusted analysis will be shown in the final presentation. Citation Format: Noel Estrada-Merly, James F Wu, Anita D'Souza. Self-reported distress in multiple myeloma patients at first consultation at a transplant referral center [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr B141.

Abstract A097: Racial and ethnic disparities in risk of persistent opioid use in a diverse cohort of breast cancer survivors and matched women without cancer

Abstract Background: Persistent opioid use (POU) in breast cancer survivors after they have completed active cancer treatment is an emerging area of concern. Disparities affecting the risk of POU remains understudied in breast cancer survivors. We evaluated disparities in examining the risk with POU in breast cancers survivors in the year after active cancer treatment along with a comparison group. Methods: We assembled a cohort of 14,347 female breast cancer (BC) survivors diagnosed in 2009-2019 treated for early-stage disease (in situ, local, regional), who had at least two opioid prescriptions after one year of survivorship and 51,369 age-matched women without cancer. Data were captured from the tumor registry, electronic health records, and pharmacy databases. The primary outcome was POU defined as continuously receiving at least 90 days supplies of opioids during follow-up. Patients were followed through the date once they met POU criteria, died, disenrolled from health plan, or reached study’s end (12/31/2021), whichever came first. We used the multivariable proportional hazard regression to estimate the association [hazard ratios (HR), 95% confidence interval (CI)] between race ethnicity and POU. Results: Overall, the cohort was diverse: 7% Asian/Pacific Islander (API); 14% Black; 28% Hispanic; and 50% White women. During a median follow-up of 6.4 years, 11134 (17%) women developed POU. Patients who developed POU had longer annualized median opioid duration, especially in Black patients (175 vs. 5 days) and were prescribed stronger opioids [median maximum daily morphine milligram equivalent (62.5 vs 42.9)], compared to those who did not develop POU. In the multivariable analyses adjusted for sociodemographic characteristics, opioid type, and other pain medications, Black, Hispanic and API women were 28%, 42% and 54% less likely to develop POU compared to White women [HR (95%CI): 0.72 (0.68-0.76), 0.58 (0.55-0.61), and 0.46 (0.42-0.52), respectively]. However, Black women were only 19% less likely [HR (95%CI): 0.81(0.72-0.92)] to develop POU compared to White women in BC survivors. Also, patients with older age, Elixhauser Comorbidity Index ≥3; smoking, type of opioid (Oxycodone and hydrocodone), and who used other psychiatric and pain medications had significantly greater POU risk. Conclusion: Findings suggest that women of color were less likely to develop POU. Further studies will include further examining clinical and pharmacological management which might have played a role in the race ethnicity groups. Citation Format: Lie Hong Chen, Rulin C. Hechter, Jiaxiao Shi, Zheng Gu, Moira Brady-Rogers, Rowan T. Chlebowski, Reina Hague. Racial and ethnic disparities in risk of persistent opioid use in a diverse cohort of breast cancer survivors and matched women without cancer [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr A097.

Abstract C069: Unraveling the complexity of malignant peritoneal mesothelioma: A comprehensive case study of diagnosis, clinical features, and therapeutic challenges in a 75-year-old male

Abstract Introduction: Malignant Peritoneal Mesothelioma (MPM) is a rare and aggressive intra-abdominal neoplasm originating from mesothelial cells. Although asbestos exposure is a known risk factor, MPM's molecular pathogenesis differs from its pleural counterpart. Case Presentation: A 75-year-old male, with a past medical history of recently diagnosed mesothelioma, presented to the emergency department for a two-week progression of abdominal distension, early satiety, and dyspnea aggravated by activity. One year prior, he initiated medical evaluation for fluid retention and abdominal distension. A recent omental biopsy confirmed the diagnosis of mesothelioma, prompting the initiation of chemotherapy every three weeks. Despite paracentesis performed monthly, the patient experienced worsening shortness of breath and early satiety post-chemotherapy. Discussion: Malignant Peritoneal Mesothelioma poses a diagnostic challenge due to the absence of specific signs or symptoms. Common manifestations include abdominal distension, pain, early satiety, weight loss, dyspnea, chest pain, and fatigue. Rare symptoms encompass new-onset hernia, fever of unknown origin, night sweats, or incidental findings during physical examinations or laparoscopy. Delays in presentation and diagnosis contribute to the advanced stage at diagnosis, with most cases having already spread throughout the abdominal cavity. Three distinct presentations of MPM include the Dry Painful Type, characterized by abdominal pain with minimal ascites; the Wet Type, presenting with abdominal distension and ascites; and the Mixed Type, combining abdominal pain and distension. Paraneoplastic phenomena, such as fever, thrombocytosis, malignancy-related thrombosis, hypoglycemia, hypoalbuminemia, paraneoplastic hepatopathy, and rarely, Coombs-positive Hemolytic anemia, further complicate the clinical picture. Surgical gross and microscopic descriptions of liver biopsies indicated chronic hepatitis with mild portal inflammation, grade 1, and no fibrosis, stage 0. Notably, the omental biopsy confirmed Malignant Mesothelioma of the epithelioid type. Immunohistochemical stains supported the diagnosis, revealing positivity for CK AE1/AE3, calretinin, WT1, CK7 (focally), and GATA3 (focally), while testing negative for BAP1, CDX2, chromogranin, CK20, hepatocyte antigen, PAX8, PSA, synaptophysin, and TTF1. Due to the rarity of MPM, no standardized treatment protocols exist. Cytoreductive surgery (CRS) and hyperthermic intraoperative peritoneal perfusion with chemotherapy (HIPEC) are recommended for selected patients without extraperitoneal disease spread, possessing a good performance status and potential for complete surgical cytoreduction. Systemic chemotherapy, particularly pemetrexed-based regimens, is advocated for patients ineligible for CRS/HIPEC. Conclusion: MPM's aggressive nature poses diagnostic and therapeutic challenges. The scarcity of standardized guidelines emphasizes the importance of ongoing research to enhance understanding, improve diagnostics, and develop targeted therapies Citation Format: Aliya M Khan, Mehmet Hepgur, Aryama Sharma. Unraveling the complexity of malignant peritoneal mesothelioma: A comprehensive case study of diagnosis, clinical features, and therapeutic challenges in a 75-year-old male [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C069.