Genetic testing in an ethnically diverse cohort of high-risk women: a comparative analysis of BRCA1 and BRCA2 mutations in American families of European and African ancestry

Molecular targets and therapies associated with poor prognosis of triple‑negative breast cancer (Review)

Triple‑negative breast cancer (TNBC) is a highly aggressive and heterogeneous subtype of BC characterized by the absence of estrogen, progesterone and human EGFR2 receptors. This lack of receptors renders it unresponsive to standard targeted therapies. Despite advances made in understanding the molecular landscape of TNBC, its poor prognosis and high recurrence rates underscore the urgent need for innovative therapeutic approaches. This review explores the effects of key prognostic markers, such as Ki‑67, programmed cell death ligand 1, BRCA1/2 mutations, E‑cadherin loss and EGFR alterations. It also examines critical pathways, including the PI3K/AKT/mTOR and mutant p53 pathways, which are prerequisites for TNBC progression and therapy resistance, and discusses the therapeutic potential of directly targeting these key molecules and their associated signaling pathways. In addition, recent advances in targeted therapies were highlighted, such as immune checkpoint inhibitors, and the statuses of emerging strategies were presented, such as chimeric antigen receptor‑T cell therapy and small inhibitory RNA‑based treatments. Given the molecular heterogeneity of TNBC, the importance of precision medicine was also discussed and it was emphasized that this approach is becoming an increasingly critical aspect of personalized treatment strategies. Resistance to existing therapies presents a major challenge to the effective treatment of TNBC, and thus, the development of future therapeutic strategies requires technical innovations. By integrating these insights, this review aims to provide a comprehensive overview of current and future means of improving TNBC outcomes.

Universal Genetic Counseling and Testing for Black Women: A Risk-Stratified Approach to Addressing Breast Cancer Disparities

Black women experience disproportionate breast cancer-related mortality, with similar overall incidence to White women. Approaches to address these racial health disparities should be multifaceted. Universal genetic counseling and testing for Black women could represent one dimension of a comprehensive approach in guiding early identification of those more likely to experience higher breast cancer-related mortality. The increased risk of triple-negative breast cancer and greater likelihood of early-onset breast cancer among Black women are 2 major justifications, given that these elements are already preexisting testing criteria per the National Comprehensive Cancer Network. Increasing assessment of breast cancer-related risk in the Black community through universal genetic counseling and testing should be considered to focus enhanced screening and preventive measures in a tailored risk-appropriate context.

Reclassification of variants of uncertain significance by race, ethnicity, and ancestry for patients at risk for breast cancer

Introduction

Although most variants of uncertain significance (VUS) in breast cancer susceptibility genes are eventually downgraded to benign or likely benign in individuals of European ancestry, it is unclear if this also applies to non-European populations. This study examines the time to and type of VUS reclassification among a diverse cohort at risk for breast cancer.

Methods

A multicenter retrospective analysis examined people assigned female at birth (AFAB) who underwent genetic testing from 2013 to 2021 with VUS in ATM, BARD1, BRCA1/2, CDH1, CHEK2, NF1, PALB2, PTEN, RAD51C/D, STK11, and/or TP53. Demographic data were collected [including race, ethnicity, and ancestry (REA)], as well as time to and type of reclassification. Frequency data and univariable and multivariable analyses were performed (p < 0.05 was considered statistically significant).

Results

There were 932 participants who had a total of 1,032 VUS (905 unique variants), with 20% who underwent reclassification of their results. The proportion of reclassified VUS among the largest represented REA groups was 19%, 23%, and 27% for White, Black or African American, and Asian people, respectively. REA was not associated with VUS reclassification (p = 0.25). The mean time to VUS reclassification was 2.8 years and was not significantly associated with REA (p = 0.16). Most VUS were downgraded to benign/likely benign (n = 187, 92%).

Discussion

Our findings demonstrate that REA is not significantly associated with VUS reclassification or time to reclassification, with the majority of VUS being downgraded across REA. This study allows for improved and more equitable genetic counseling. It may also provide more reassurance to those groups that may have a higher likelihood of VUS results.

Homologous recombination deficiency in ovarian high-grade serous carcinoma by self-reported race

Background

Approximately half of ovarian high-grade serous carcinomas (HGSC) have homologous recombination deficiency (HRD). However, HRD is not well-characterized in Black individuals.

Objective

To characterize HGSC HRD by self-reported race and evaluate whether differences in HRD are associated with ovarian cancer mortality.

Study population

Cohort study using data collected from two population-based case-control studies of ovarian cancer. Cases were selected based on self-reported race (178 Black, 123 White) and pathologically-confirmed HGSC.

Exposures

HRD features identified using matched tumor-normal whole-exome DNA sequencing and categorized as germline or somatic variants in homologous recombination pathway genes, or the SBS3 HRD-associated signature.

Outcomes

Median difference and 95% confidence intervals (CI) for age at diagnosis and tumor mutation burden, and age and stage-adjusted hazard ratios (HR) and 95%CIs for survival, comparing individuals with an HRD feature to those without, separately by self-reported race.

Results

More of the germline and somatic variants detected among Black individuals compared with White individuals were unannotated or variants of uncertain significance (VUS; germline 65% versus 45%; somatic 62% versus 50%, respectively). While the prevalences of many HRD features were similar between Black individuals and White individuals, Black individuals had a higher prevalence of the HRD signature identified using de novo mutational signature analysis (40% versus 29%) and germline BRCA2 variants (8% versus 2%) compared with White individuals. We observed that among Black individuals, BRCA2 variants were associated with better survival (somatic HR=0.23, 95%CI 0.07-0.76; germline HR=0.48, 95%CI 0.22-1.03), while germline BRCA1 variants were associated with worse survival (HR=2.11, 95%CI 1.14-3.88). When we restricted to VUS and unannotated variants, we observed similar associations with survival for BRCA2 among Black individuals (somatic HR=0.18, 95%CI 0.04-0.75; germline HR=0.40, 95%CI 0.15-1.09).

Conclusions and Relevance

HRD testing informs precision-based medicine approaches that improve outcomes, but a higher proportion of VUS among Black individuals may complicate referral for such care. Our findings emphasize the importance of recruiting diverse individuals in genomics research and better characterizing VUS.

Obesity and lack of breastfeeding: a perfect storm to augment risk of breast cancer?

Triple-negative breast cancer (TNBC) is one of the most aggressive subtypes of breast cancer with higher rates of recurrence and distant metastasis, as well as decreased 5-year survival rates. Racial disparities are evident in the incidence and mortality rates of triple negative breast cancer particularly increased in young African American women. Concurrently, young African American women have multiple risk factors for TNBC including higher rates of premenopausal abdominal obesity (higher waist-hip ratio) and lower rates of breastfeeding with higher parity, implicating these factors as potentially contributors to poor outcomes. By understanding the mechanisms of how premenopausal obesity and lack of breastfeeding may be associated with increased risk of triple negative breast cancer, we can determine the best strategies for intervention and awareness to improve outcomes in TNBC.

Cancer patients' experience of receiving variant of uncertain significance results: An Asian perspective

Due to a lack of ancestry-matched, functional, and segregation data, Asians have a higher rate of receiving a variant of uncertain significance (VUS) result following panel testing. Managing VUS results presents challenges, as it often leads to increased anxiety and distress among cancer patients undergoing genetic testing. This exploratory study aims to investigate the experience of Asian cancer patients upon receiving a VUS result. A qualitative, semi-structured interview study was conducted, involving cancer patients who had received a VUS result through the Cancer Genetics Service of the National Cancer Centre Singapore. Twenty participants were interviewed, and their responses were transcribed and analyzed using thematic analysis to identify key themes. Thematic analysis revealed five major themes: (1) VUS results are interpreted as uncertain outcomes; (2) a VUS result provides relief and prompts positive behavioral adjustments; (3) patients employ fatalism and religion as coping mechanisms to navigate uncertainty; (4) genetic counselors, family, and the community offer reassurance and support; (5) patients value updates on variant classifications for future management. While this novel study provides unique insights into the perspectives of Asian patients who receive VUS results, it also highlights patients' effective management of VUS results and uncertainty, which has implications for improving counseling practices in Asia. Emphasis must be placed on accurate interpretation and clear communication of VUS results to dispel the possibility of misconceptions, misdiagnosis, and mismanagement in cancer care.

Gynecologic Care of Black Breast Cancer Survivors

Purpose of Review

Black patients suffer from breast cancer-related racial health disparities, which could have implications on their gynecologic care. This review explores considerations in the gynecologic care of Black breast cancer survivors.

Recent Findings

Black people have a higher risk of leiomyoma and endometrial cancer, which could confound bleeding patterns such as in the setting of tamoxifen use. As Black people are more likely to have early-onset breast cancer, this may have implications on long-term bone and heart health. Black patients may be more likely to have menopausal symptoms at baseline and as a result of breast cancer treatment. Furthermore, Black patients are less likely to utilize assisted reproductive technology and genetic testing services.

Summary

It is important for healthcare providers to be well-versed in the intersections of breast cancer and gynecologic care. Black breast cancer survivors may have unique considerations for which practitioners should be knowledgeable.

A Public Health Emergency: Breast Cancer Among Black Communities in the United States

While Black people have a similar incidence of breast cancer compared to White people, they have a 40% increased death rate. Black people are more likely to be diagnosed with aggressive subtypes such as triple-negative breast cancer. However, despite biological factors, systemic racism and social determinants of health create delays in care and barriers to treatment. While genetic testing holds incredible promise for Black people, uptake remains low and results may be challenging to interpret. There is a need for more robust, multidisciplinary, and antiracist interventions to reverse breast cancer-related racial disparities.

Genetic contribution of breast cancer genes in women of black African origin

Breast cancer (BC) is an increasing public health issue worldwide. BC incidence and mortality rates are rising in transitioning countries in Africa, with the most rapid increase occurring in Sub-Saharan Africa (SSA). Female BC represents 25.8% of all cancer diagnosis in SSA. Early age at onset, high grade and triple negative tumors are hallmarks of BC in this region, associated with germline pathogenic variants in susceptibility genes. While several genes have been associated with genetic predisposition (BRCA1, BRCA2, PALB2, TP53, PTEN, CDH1, STK11, ATM, CHEK2, NBN, BARD1, BRIP1, RAD50, RAD51C, RAD51D, … ), most studies have reported contribution of BRCA1 and BRCA2 pathogenic variants. Genetic contribution of BRCA genes has been estimated at 27% in Caucasian women. Available data from population of African origin are scarce and have mainly focused on pathogenic variants of BRCA1 and BRCA2. Reports from main studies on large sample size highlighted that BRCA1 still the major gene associated with BC in SSA. In addition, BRCA2, PALB2, and P53, are also on the top major genes with high penetrance, associated with BC. Mutation spectrum of BC genes in black African women seems to be different from Caucasian with increasing number of founder mutations identified. We hypothesis that the genetic contribution of known BC genes may be different between women of black African origin compared to Caucasians. In this review we explore the genetic contribution of known breast cancer genes in women of African origin, and discuss perspectives for prevention and patients care strategies in the era of precision medicine.

Challenges in periodic revision of genetic testing results: Comparison of the main classification guidelines and report of a retrospective analysis involving BRCA1/BRCA2 variants of uncertain significance

In the context of cancer predisposition syndromes, it is widely known that the correct interpretation of germline variants identified in multigene panel testing is essential for adequate genetic counseling and clinical decision making, in which variants of uncertain significance (VUS) are not considered actionable findings. Thus, their periodic re-evaluation using appropriate guidelines is notably important. In the present study, we compared the performance of the main variant classification guidelines (ACMG, Sherloc and ENIGMA) in variant reassessment, using as input a BRCA1/2 VUS case series (retrospective analysis) from Brazil, an ethnically diverse and admixed country with substantial challenges in VUS reclassification. As main findings, two of the 15 VUS analyzed were reclassified as likely pathogenic by the 3 guidelines, BRCA1 c.4987-3C > G (rs397509213) and BRCA2 c.7868A > G (rs80359012). Moreover, challenges in variant classification and reassessment are described and additional in silico data about structural impact of the variant BRCA2 c.7868A > G are provided. We hypothesize that the establishment of a framework to reassess VUS could improve this process in health centers that have not yet implemented this practice. Results of this study underscore that periodic monitoring of the functional, clinical, and bioinformatics data of a VUS by a multidisciplinary team are of utmost importance in clinical practice. When there is a specific guideline for a given gene, such as ENIGMA for BRCA1/2, it should be considered the first option for variant assessment. Finally, recruitment of VUS carriers and their relatives to participate in variant segregation studies and publication of VUS reclassification results in the international scientific literature should be encouraged.

BRCA1 and BRCA2 germline mutation analysis from a cohort of 1267 patients at high risk for breast cancer in Brazil

We determined the frequency and mutational spectrum of BRCA1 and BRCA2 in a series of patients at high risk for developing breast cancer from Brazil. A total of 1267 patients were referred for BRCA genetic testing, and no obligation of fulfilling criteria of mutation probability methods for molecular screening was applied. Germline deleterious mutations in BRCA1/2 (i.e., pathogenic/likely pathogenic variants) were identified in 156 out of 1267 patients (12%). We confirm recurrent mutations in BRCA1/2, but we also report three novel mutations in BRCA2, not previously reported in any public databases or other studies. Variants of unknown significance (VUS) represent only 2% in this dataset and most of them were detected in BRCA2. The overall mutation prevalence in BRCA1/2 was higher in patients diagnosed with cancer at age > 35 years old, and with family history of cancer. The present data expand our knowledge of BRCA1/2 germline mutational spectrum, and it is a valuable clinical resource for genetic counseling and cancer management programs in the country.

A metabolome-wide case-control study of african american breast cancer patients

BACKGROUND

Breast cancer survivors face long-term sequelae compared to the general population, suggesting altered metabolic profiles after breast cancer. We used metabolomics approaches to investigate the metabolic differences between breast cancer patients and women in the general population, aiming to elaborate metabolic changes among breast cancer patients and identify potential targets for clinical interventions to mitigate long-term sequelae.

METHODS

Serum samples were retrieved from 125 breast cancer cases recruited from the Chicago Multiethnic Epidemiologic Breast Cancer Cohort (ChiMEC), and 125 healthy controls selected from Chicago Multiethnic Prevention and Surveillance Study (COMPASS). We used liquid chromatography-high resolution mass spectrometry to obtain untargeted metabolic profiles and partial least squares discriminant analysis (PLS-DA) combined with fold change to select metabolic features associated with breast cancer. Pathway analyses were conducted using Mummichog to identify differentially enriched metabolic pathways among cancer patients. As potential confounders we included age, marital status, tobacco smoking, alcohol drinking, type 2 diabetes, and area deprivation index in our model. Random effects of residence for intercept was also included in the model. We further conducted subgroup analysis by treatment timing (chemotherapy/radiotherapy/surgery), lymph node status, and cancer stages.

RESULTS

The entire study participants were African American. The average ages were 57.1 for cases and 58.0 for controls. We extracted 15,829 features in total, among which 507 features were eventually selected by our criteria. Pathway enrichment analysis of these 507 features identified three differentially enriched metabolic pathways related to prostaglandin, leukotriene, and glycerophospholipid. The three pathways demonstrated inconsistent patterns. Metabolic features in the prostaglandin and leukotriene pathways exhibited increased abundances among cancer patients. In contrast, metabolic intensity in the glycerolphospholipid pathway was deregulated among cancer patients. Subgroup analysis yielded consistent results. However, changes in these pathways were strengthened when only using cases with positive lymph nodes, and attenuated when only using cases with stage I disease.

CONCLUSION

Breast cancer in African American women is associated with increase in serum metabolites involved in prostaglandin and leukotriene pathways, but with decrease in serum metabolites in glycerolphospholipid pathway. Positive lymph nodes and advanced cancer stage may strengthen changes in these pathways.

Using species richness calculations to model the global profile of unsampled pathogenic variants: Examples from BRCA1 and BRCA2

There have been many surveys of genetic variation in BRCA1 and BRCA2 to identify variant prevalence and catalogue population specific variants, yet none have evaluated the magnitude of unobserved variation. We applied species richness estimation methods from ecology to estimate "variant richness" and determine how many germline pathogenic BRCA1/2 variants have yet to be identified and the frequency of these missing variants in different populations. We also estimated the prevalence of germline pathogenic BRCA1/2 variants and identified those expected to be most common. Data was obtained from a literature search including studies conducted globally that tested the entirety of BRCA1/2 for pathogenic variation. Across countries, 45% to 88% of variants were estimated to be missing, i.e., present in the population but not observed in study data. Estimated variant frequencies in each country showed a higher proportion of rare variants compared to recurrent variants. The median prevalence estimate of BRCA1/2 pathogenic variant carriers was 0.64%. BRCA1 c.68_69del is likely the most recurrent BRCA1/2 variant globally due to its estimated prevalence in India. Modeling variant richness using ecology methods may assist in evaluating clinical targeted assays by providing a picture of what is observed with estimates of what is still unknown.

Combining Breast Cancer Risk Prediction Models

Accurate risk stratification is key to reducing cancer morbidity through targeted screening and preventative interventions. Multiple breast cancer risk prediction models are used in clinical practice, and often provide a range of different predictions for the same patient. Integrating information from different models may improve the accuracy of predictions, which would be valuable for both clinicians and patients. BRCAPRO is a widely used model that predicts breast cancer risk based on detailed family history information. A major limitation of this model is that it does not consider non-genetic risk factors. To address this limitation, we expand BRCAPRO by combining it with another popular existing model, BCRAT (i.e., Gail), which uses a largely complementary set of risk factors, most of them non-genetic. We consider two approaches for combining BRCAPRO and BCRAT: (1) modifying the penetrance (age-specific probability of developing cancer given genotype) functions in BRCAPRO using relative hazard estimates from BCRAT, and (2) training an ensemble model that takes BRCAPRO and BCRAT predictions as input. Using both simulated data and data from Newton-Wellesley Hospital and the Cancer Genetics Network, we show that the combination models are able to achieve performance gains over both BRCAPRO and BCRAT. In the Cancer Genetics Network cohort, we show that the proposed BRCAPRO + BCRAT penetrance modification model performs comparably to IBIS, an existing model that combines detailed family history with non-genetic risk factors.

Racial and ethnic variation in BRCA1 and BRCA2 genetic test results among individuals referred for genetic counseling at a large urban comprehensive cancer center

PURPOSE

The prevalence of pathogenic variants in BRCA1 and BRCA2 in populations other than Ashkenazi Jewish (AJ) is not well defined. We describe the racial and ethnic-specific prevalence of BRCA1/2 pathogenic variants and variants of uncertain significance (VUS) among individuals referred for genetic testing in a large urban comprehensive cancer center over a 20-year period.

METHODS

The population included 3,537 unrelated individuals who underwent genetic testing from January 1999 to October 2019 at the Karmanos Cancer Institute. We estimated the prevalence of pathogenic variants and VUS and evaluated associations with race and ethnicity for African American (AA), Arab, AJ and Hispanic individuals compared to Non-Hispanic Whites (NHW). We used multivariable models to adjust for other predictors of pathogenic variants. We also reported the most common pathogenic variants by racial and ethnic group.

RESULTS

The racial and ethnic breakdown of our population was: NHW (68.9%), AA (20.3%), AJ (2.5%), Arab (2.2%), Hispanic (1.0%), Asian Pacific Islander, Native American/Alaskan Native (4.7%), and < 1% unknown. The overall prevalence of pathogenic variants in BRCA1/2 was 8.9% and the prevalence of VUS was 5.6%. Compared to NHW, there were no racial or ethnic differences in the rate of pathogenic variants. However, AA individuals were more likely to have VUS in BRCA1 (adjusted OR 2.43, 95% CI 1.38-4.28) and AJ were more likely to have VUS in BRCA2 (adjusted OR 3.50, 95% CI 1.61-6.58).

CONCLUSION

These results suggest the continued need for genetic testing and variant reclassification for individuals of all racial and ethnic groups.

Disparities in Breast Cancer Outcomes and How to Resolve Them

There has been a 40% decline in breast cancer age-adjusted death rate since 1990. Black American women have not experienced as great a decline; indeed, the Black-White disparity in mortality in the United States is greater today than it has ever been. Certain states (areas of residence), however, do not see such dramatic differences in outcome by race. This latter finding suggests much more can be done to reduce disparities and prevent deaths. Interventions to get high-quality care (screening, diagnostics, and treatment) involve understanding the needs and concerns of the patient and addressing those needs and concerns. Patient navigators are 1 way to improve outcomes.

Disparities in cancer genetics care by race/ethnicity among pan-cancer patients with pathogenic germline variants

BACKGROUND

Germline risk assessment is increasing as part of cancer care; however, disparities in subsequent genetic counseling are unknown.

METHODS

Pan-cancer patients were prospectively consented to tumor-normal sequencing via custom next generation sequencing panel (Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets) inclusive of germline analysis of ≥76 genes from January 2015 through December 2019 (97.5% research nonbillable) with protocol for genetics referral. Rates of pathogenic/likely pathogenic germline variants (PVs) and downstream counseling were compared across ancestry groups (mutually exclusive groups based on self-reported race/ethnicity and Ashkenazi Jewish [AJ] heritage) using nonparametric tests and multivariable logistic regression models.

RESULTS

Among 15,775 patients (59.6%, non-Hispanic [NH]-White; 15.7%, AJ; 20.5%, non-White [6.9%, Asian; 6.8%, Black/African American (AA); 6.7%, Hispanic; 0.1%, Other], and 4.2%, unknown), 2663 (17%) had a PV. Non-White patients had a lower PV rate (n = 433, 13.4%) compared to NH-Whites (n = 1451, 15.4%) and AJ patients (n = 683, 27.6%), p < .01, with differences in mostly moderate and low/recessive/uncertain penetrance variants. Among 2239 patients with new PV, 1652 (73.8%) completed recommended genetic counseling. Non-White patients had lower rates of genetic counseling (67.7%) than NH-White (73.7%) and AJ patients (78.8%), p < .01, with lower rates occurring in Black/AA (63%) compared to NH-White patients, even after adjustment for confounders (odds ratio, 0.60; 95% confidence interval, 0.37-0.97; p = .036). Non-White, particularly Black/AA and Asian, probands had a trend toward lower rates and numbers of at-risk family members being seen for counseling/genetic testing.

CONCLUSIONS

Despite minimizing barriers to genetic testing, non-White patients were less likely to receive recommended cancer genetics follow-up, with potential implications for oncologic care, cancer risk reduction, and at-risk family members.

LAY SUMMARY

Genetic testing is becoming an important part of cancer care, and we wanted to see if genetics care was different between individuals of different backgrounds. We studied 15,775 diverse patients with cancer who had genetic testing using a test called MSK-IMPACT that was covered by research funding. Clinically important genetic findings were high in all groups. However, Black patients were less likely to get recommended counseling compared to White patients. Even after removing many roadblocks, non-White and especially Black patients were less likely to get recommended genetics care, which may affect their cancer treatments and families.

Enrollment of Individuals From Racial and Ethnic Minority Groups in Gynecologic Cancer Precision Oncology Trials

OBJECTIVE

To characterize whether enrollment patterns in precision oncology clinical trials for gynecologic cancers reflect the racial and ethnic diversity of patients with gynecologic cancers in the United States.

METHODS

ClinicalTrials.gov was queried to perform this cross-sectional review. We included precision oncology trials -defined as trials using molecular profiling of a tumor or the patient genome to identify targetable alterations to guide treatment-of ovarian, uterine, cervical, and vulvar cancers in the United States. National Cancer Institute Surveillance, Epidemiology, and End Results and United States Census Bureau data were used to estimate cancer burden and the expected number of trial participants by race and ethnicity for each gynecologic cancer. The ratio of actual-to-expected participants was calculated. A ratio greater than 1 signified overenrollment. A random effects meta-analysis was performed to assess the relative weights of individual trials.

RESULTS

We identified 493 trials, 61 of which met inclusion criteria. There were 2,573 patients enrolled in ovarian cancer trials, 1,197 in uterine cancer trials and 162 in cervical cancer trials. Non-Hispanic White women were overrepresented overall (enrollment ratio 1.26, 95% CI 1.20-1.32) and across all cancer types on subgroup analysis. Asian women, non-Hispanic Black women, and Hispanic women were underrepresented overall (enrollment ratios 0.63, 95% CI 0.41-0.86; 0.51, 95% CI 0.36-0.66 and 0.30, 95% CI 0.23-0.36, respectively). In subgroup analyses, Asian women and non-Hispanic Black women were underrepresented in ovarian and uterine cancer trials and Hispanic women were underrepresented across all cancer types.

CONCLUSION

Non-Hispanic Black women, Asian women, and Hispanic women with gynecologic cancers are underrepresented in precision oncology trials. Few U.S.-based precision oncology trials exist for uterine and cervical cancers, which have a high burden of morbidity and mortality among racial and ethnic minority groups. Failure to equitably enroll patients who belong to racial and ethnic minority groups may perpetuate existing disparities in gynecologic cancer outcomes.

Screening of BRCA1 (c.5177_5180delGAAA rs80357867 and c.4986+6T>C rs80358086) and the BRCA2 (c.6445_6446delAT rs80359592) Genes for Breast Cancer Prevention in Burkina Faso

Background

The objective of this study is to search for mutations in the BRCA1 (c.5177_5180delGAAA and c.4986+6T>C) and BRCA2 genes (c.6445_6446delAT) in a population of women diagnosed with breast cancer.

Methods

This is a case-control study that involved 140 participants, including 70 patients with histologically diagnosed breast cancer and 70 healthy women without breast cancer. Mutations in the BRCA1 (rs80357867, rs80358086) and BRCA2 (rs80359592) genes were tested by real-time PCR. The 95% confidence interval Odds Ratio (OR) was used to estimate the associations between specific genotypes and breast cancer.

Results

The study revealed that no mutations were detected for rs80359592. Similarly, no reference allele (TTTC/TTTC) of rs80357867 was found in this study. However, the homozygous double mutant (-/) genotype of this rs80357867 was observed in 11.43% and 1.43% of patients and controls respectively, while 88.57% of patients and 98.57% of controls had a heterozygous deletion (TTTC/-). Concerning rs80358086, 8.57% of the patients had a heterozygous mutation (A/G) with no significantly risk association with occurrence of breast cancer (OR = 6.46; 95% CI: 0.75-55.21; p = 0.11). In addition, this heterozygous mutation was significantly associated with a family history of breast cancer (OR=128; 95% CI: 9.46-1730.93) and breast cancer risk in nonmultiparous women (OR=6; 95% CI: 1-35.90; p= 0.05) but no association with overweight/obesity (OR=1.66; 95% CI: 0.18-15.35; p=1).

Conclusion

This study shows high frequencies of heterozygous mutation of rs80357867 and rs80358086 from patients. In Burkina Faso, these results could help with early diagnosis of breast cancer in patients.

Evaluating breast cancer predisposition genes in women of African ancestry

PURPOSE

Studies conducted primarily among European ancestry women reported 12 breast cancer predisposition genes. However, etiologic roles of these genes in breast cancer among African ancestry women have been less well-investigated.

METHODS

We conducted a case-control study in African American women, which included 1117 breast cancer cases and 2169 cancer-free controls, and a pooled analysis, which included 7096 cases and 8040 controls of African descent. Odds ratios of associations with breast cancer risk were estimated.

RESULTS

Using sequence data, we identified 61 pathogenic variants in 12 breast cancer predisposition genes, including 11 pathogenic variants not yet reported in previous studies. Pooled analysis showed statistically significant associations of breast cancer risk with pathogenic variants in BRCA1, BRCA2, PALB2, ATM, CHEK2, TP53, NF1, RAD51C, and RAD51D (all P < .05). The associations with BRCA1, PALB2, and RAD51D were stronger for estrogen receptor (ER)-negative than for ER-positive breast cancer (P heterogeneity < .05), whereas the association with CHEK2 was stronger for ER-positive than for ER-negative breast cancer.

CONCLUSION

Our study confirmed previously identified associations of breast cancer risk with BRCA1, BRCA2, PALB2, ATM, TP53, NF1, and CHEK2 and provided new evidence to extend the associations of breast cancer risk with RAD51C and RAD51D, which was identified previously in European ancestry populations, to African ancestry women.

Equity in Genomic Medicine

Since the completion of the Human Genome Project, considerable progress has been made in translating knowledge about the genetic basis of disease risk and treatment response into clinical services and public health interventions that have greater precision. It is anticipated that more precision approaches to early detection, prevention, and treatment will be developed and will enhance equity in healthcare and outcomes among disparity populations. Reduced access to genomic medicine research, clinical services, and public health interventions has the potential to exacerbate disparities in genomic medicine. The purpose of this article is to describe these challenges to equity in genomic medicine and identify opportunities and future directions for addressing these issues. Efforts are needed to enhance access to genomic medicine research, clinical services, and public health interventions, and additional research that examines the clinical utility of precision medicine among disparity populations should be prioritized to ensure equity in genomic medicine. Expected final online publication date for the Annual Review of Genomics and Human Genetics, Volume 23 is October 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

New Insights Into c.815_824dup Pathogenic Variant of BRCA1 in Inherited Breast Cancer: A Founder Mutation of West African Origin

Founder mutations have been reported in BRCA1 and BCRA2 in different ethnic groups with inherited breast cancer. Testing of targeted mutations in specific populations is important for cancer prevention in mutation carriers. In Sub-Saharan Africa, only a few studies have reported specific founder mutations in inherited breast cancer. The pathogenic variant c.815_824dup of BRCA1 has been reported as the most frequent among African American populations with inherited breast cancer and was supposed to have a West African origin. Recent report from Senegal identified this variant in women with inherited breast cancer at the highest frequency ever reported. The variant was linked to a common haplotype confirming its founder effect in West Africa. In this article, we review the mutation history of c.815_824dup and discuss how it spread out of Africa through the transatlantic slave trade.

BRCA1 Variant Assessment Using a Simple Analytic Assay

BACKGROUND

We previously developed a biological assay to accurately predict BRCA1 (BRCA1 DNA repair associated) mutation status, based on gene expression profiles of Epstein-Barr virus-transformed lymphoblastoid cell lines. The original work was done using whole genome expression microarrays, and nearest shrunken centroids analysis. While these approaches are appropriate for model building, they are difficult to implement clinically, where more targeted testing and analysis are required for time and cost savings.

METHODS

Here, we describe adaptation of the original predictor to use the NanoString nCounter platform for testing, with analysis based on the k-top scoring pairs (k-TSP) method.

RESULTS

Assessing gene expression using the nCounter platform on a set of lymphoblastoid cell lines yielded 93.8% agreement with the microarray-derived data, and 87.5% overall correct classification of BRCA1 carriers and controls. Using the original gene expression microarray data used to develop our predictor with nearest shrunken centroids, we rebuilt a classifier based on the k-TSP method. This classifier relies on the relative expression of 10 pairs of genes, compared to the original 43 identified by nearest shrunken centroids (NSC), and was 96.2% concordant with the original training set prediction, with a 94.3% overall correct classification of BRCA1 carriers and controls.

CONCLUSIONS

The k-TSP classifier was shown to accurately predict BRCA1 status using data generated on the nCounter platform and is feasible for initiating a clinical validation.

Impact of Variant Reclassification in Cancer Predisposition Genes on Clinical Care

PURPOSE

Genetic testing has clinical utility in the management of patients with hereditary cancer syndromes. However, the increased likelihood of encountering a variant of uncertain significance in individuals of non-European descent such as Asians may be challenging to both clinicians and patients. This study aims to evaluate the impact of variant reclassification in an Asian country with variants of uncertain significance reported in cancer predisposition genes.

METHODS

A retrospective analysis of patients seen at the Cancer Genetics Service at the National Cancer Centre Singapore between February 2014 and March 2020 was conducted. The frequency, direction, and time to variant reclassification were evaluated by comparing the reclassified report against the original report.

RESULTS

A total of 1,412 variants of uncertain significance were reported in 49.9% (845 of 1,695) of patients. Over 6 years, 6.7% (94 of 1,412) of variants were reclassified. Most variants of uncertain significance (94.1%, 80 of 85) were downgraded to benign or likely benign variant, with a smaller proportion of variants of uncertain significance (5.9%, 5 of 85) upgraded to pathogenic or likely pathogenic variant. Actionable variants of uncertain significance upgrades and pathogenic or likely pathogenic variant downgrades, which resulted in management changes, happened in 31.0% (39 of 126) of patients. The median and mean time taken for reclassification were 1 and 1.62 year(s), respectively.

CONCLUSION

We propose a clinical guideline to standardize management of patients reported to have variants of uncertain significance. Management should be based on the patient's personal history, family history, and variant interpretation. For clinically relevant or suspicious variants of uncertain significance, follow-up is recommended every 2 years, as actionable reclassifications may happen during this period.

Quantitative assessment of the immune microenvironment in African American Triple Negative Breast Cancer: a case-control study

PURPOSE

Triple negative breast cancer (TNBC) is more common in African American (AA) than Non-AA (NAA) population. We hypothesize that tumor microenvironment (TME) contributes to this disparity. Here, we use multiplex quantitative immunofluorescence to characterize the expression of immunologic biomarkers in the TME in both populations.

PATIENTS AND METHODS

TNBC tumor resection specimen tissues from a 100-patient case: control cohort including 49 AA and 51 NAA were collected. TME markers including CD45, CD14, CD68, CD206, CD4, CD8, CD20, CD3, Ki67, GzB, Thy1, FAP, aSMA, CD34, Col4, VWF and PD-L1 we quantitatively assessed in every field of view. Mean expression levels were compared between cases and controls.

RESULTS

Although no significant differences were detected in individual lymphoid and myeloid markers, we found that infiltration with CD45+ immune cells (p = 0.0102) was higher in TNBC in AA population. AA TNBC tumors also had significantly higher level of lymphocytic infiltration defined as CD45+ CD14- cells (p = 0.0081). CD3+ T-cells in AA tumors expressed significantly higher levels of Ki67 (0.0066) compared to NAAs, indicating that a higher percentage of AA tumors contained activated T-cells. All other biomarkers showed no significant differences between the AA and NAA group.

CONCLUSIONS

While the TME in TNBC is rich in immune cells in both racial groups, there is a numerical increase in lymphoid infiltration in AA compared to NAA TNBC. Significantly, higher activated T cells seen in AA patients raises the possibility that there may be a subset of AA patients with improved response to immunotherapy.

Breast cancer in West Africa: molecular analysis of BRCA genes in early-onset breast cancer patients in Burkina Faso

BACKGROUND

Breast cancer (BC) is the most commonly diagnosed cancer and the second leading cause of cancer-related deaths among women in Africa after cervical cancer. Even if the epidemiological data are now aligned with those relating to industrialized countries, the knowledge concerning breast cancer in Africa, particularly in Western Africa, still lack clinical data, medical treatments, and the evaluation of genetic and non-genetic factors implicated in the etiology of the disease. The early onset and the aggressiveness of diagnosed breast cancers in patients of African ancestry strongly suggest that the genetic risk factor may be a key component, but so far, very few studies on the impact of germ line mutations in breast cancer in Africa have been conducted, with negative consequences on prevention, awareness and patient management. Through Next Generation sequencing (NGS), we analyzed all of the coding regions and the exon-intron junctions of BRCA1 and BRCA2 genes-the two most important genes in hereditary breast cancer-in fifty-one women from Burkina Faso with early onset of breast cancer with or without a family history.

RESULTS

We identified six different pathogenic mutations (three in BRCA1, three in BRCA2), two of which were recurrent in eight unrelated women. Furthermore, we identified, in four other patients, two variants of uncertain clinical significance (VUS) and two variants never previously described in literature, although one of them is present in the dbSNP database.

CONCLUSIONS

This is the first study in which the entire coding sequence of BRCA genes has been analyzed through Next Generation Sequencing in Burkinabe young women with breast cancer. Our data support the importance of genetic risk factors in the etiology of breast cancer in this population and suggest the necessity to improve the genetic cancer risk assessment. Furthermore, the identification of the most frequent mutations of BRCA1 and BRCA2 in the population of Burkina Faso will allow the development of an inexpensive genetic test for the identification of subjects at high genetic cancer risk, which could be used to design personalized therapeutic protocols.

Revisiting social MPE: an integration of molecular pathological epidemiology and social science in the new era of precision medicine

INTRODUCTION

Molecular pathological epidemiology (MPE) is an integrative transdisciplinary area examining the relationships between various exposures and pathogenic signatures of diseases. In line with the accelerating advancements in MPE, social science and its health-related interdisciplinary areas have also developed rapidly. Accumulating evidence indicates the pathological role of social-demographic factors. We therefore initially proposed social MPE in 2015, which aims to elucidate etiological roles of social-demographic factors and address health inequalities globally. With the ubiquity of molecular diagnosis, there are ample opportunities for researchers to utilize and develop the social MPE framework.

AREAS COVERED

Molecular subtypes of breast cancer have been investigated rigorously for understanding its etiologies rooted from social factors. Emerging evidence indicates pathogenic heterogeneity of neurological disorders such as Alzheimer's disease. Presenting specific patterns of social-demographic factors across different molecular subtypes should be promising for advancing the screening, prevention, and treatment strategies of those heterogeneous diseases. This article rigorously reviewed literatures investigating differences of race/ethnicity and socioeconomic status across molecular subtypes of breast cancer and Alzheimer's disease to date.

EXPERT OPINION

With advancements of the multi-omics technologies, we foresee a blooming of social MPE studies, which can address health disparities, advance personalized molecular medicine, and enhance public health.

Investigation of triple-negative breast cancer risk alleles in an International African-enriched cohort

Large-scale efforts to identify breast cancer (BC) risk alleles have historically taken place among women of European ancestry. Recently, there are new efforts to verify if these alleles increase risk in African American (AA) women as well. We investigated the effect of previously reported AA breast cancer and triple-negative breast cancer (TNBC) risk alleles in our African-enriched International Center for the Study of Breast Cancer Subtypes (ICSBCS) cohort. Using case-control, case-series and race-nested approaches, we report that the Duffy-null allele (rs2814778) is associated with TNBC risk (OR = 3.814, p = 0.001), specifically among AA individuals, after adjusting for self-indicated race and west African ancestry (OR = 3.368, p = 0.007). We have also validated the protective effect of the minor allele of the ANKLE1 missense variant rs2363956 among AA for TNBC (OR = 0.420, p = 0.005). Our results suggest that an ancestry-specific Duffy-null allele and differential prevalence of a polymorphic gene variant of ANKLE1 may play a role in TNBC breast cancer outcomes. These findings present opportunities for therapeutic potential and future studies to address race-specific differences in TNBC risk and disease outcome.

Genetic Variants in Patients With a Family History of Pancreatic Cancer: Impact of Multigene Panel Testing

OBJECTIVES

Up to 15% of pancreatic cancer is hereditary. We aim to study the prevalence of pathogenic germline variants (PGVs) in patients referred for genetic counseling with a family history (FH) of pancreatic cancer.

METHODS

We performed a retrospective single institution cohort study of individuals who underwent cancer genetic counseling with a FH of pancreatic cancer.

RESULTS

We identified 314 patients. Genetic testing was performed in 291 (92.7%) and 187 (59.6%) underwent expanded multigene panel testing. Fifty-four PGVs were found in 53 (16.9%) individuals; PGVs in BRCA1/2 (37%) were most common. Seventy-two variants of uncertain significance (VUS) were found in 58 (18.5%) individuals; VUS in ATM (16.7%) were the most common. Of the 112 (35.4%) with a first-degree family member with pancreatic cancer, 14 PGVs were identified in 14 (12.5%) individuals and 28 VUS were identified in 21 (18.8%) individuals. After genetic testing, 47 (15.0%) individuals met International Cancer of the Pancreas Screening criteria and 67 (21.3%) met American College of Gastroenterology criteria for pancreatic surveillance.

CONCLUSIONS

Genetic testing of individuals with a FH of pancreatic cancer represents an opportunity to identify individuals who may be candidates for pancreatic surveillance.

Cancer health disparities in racial/ethnic minorities in the United States

There are well-established disparities in cancer incidence and outcomes by race/ethnicity that result from the interplay between structural, socioeconomic, socio-environmental, behavioural and biological factors. However, large research studies designed to investigate factors contributing to cancer aetiology and progression have mainly focused on populations of European origin. The limitations in clinicopathological and genetic data, as well as the reduced availability of biospecimens from diverse populations, contribute to the knowledge gap and have the potential to widen cancer health disparities. In this review, we summarise reported disparities and associated factors in the United States of America (USA) for the most common cancers (breast, prostate, lung and colon), and for a subset of other cancers that highlight the complexity of disparities (gastric, liver, pancreas and leukaemia). We focus on populations commonly identified and referred to as racial/ethnic minorities in the USA-African Americans/Blacks, American Indians and Alaska Natives, Asians, Native Hawaiians/other Pacific Islanders and Hispanics/Latinos. We conclude that even though substantial progress has been made in understanding the factors underlying cancer health disparities, marked inequities persist. Additional efforts are needed to include participants from diverse populations in the research of cancer aetiology, biology and treatment. Furthermore, to eliminate cancer health disparities, it will be necessary to facilitate access to, and utilisation of, health services to all individuals, and to address structural inequities, including racism, that disproportionally affect racial/ethnic minorities in the USA.

Impact of post-diagnosis weight change on survival outcomes in Black and White breast cancer patients

PURPOSE

To evaluate weight change patterns over time following the diagnosis of breast cancer and to examine the association of post-diagnosis weight change and survival outcomes in Black and White patients.

METHODS

The study included 2888 women diagnosed with non-metastatic breast cancer in 2000-2017 in Chicago. Longitudinal repeated measures of weight and height were collected, along with a questionnaire survey including questions on body size. Multilevel mixed-effects models were used to examine changes in body mass index (BMI). Delayed entry Cox proportional hazards models were used to investigate the impacts of changing slope of BMI on survival outcomes.

RESULTS

At diagnosis, most patients were overweight or obese with a mean BMI of 27.5 kg/m² and 31.5 kg/m² for Blacks and Whites, respectively. Notably, about 45% of the patients had cachexia before death and substantial weight loss started about 30 months before death. In multivariable-adjusted analyses, compared to stable weight, BMI loss (> 0.5 kg/m²/year) showed greater than 2-fold increased risk in overall survival (hazard ratio [HR] = 2.60, 95% CI 1.88-3.59), breast cancer-specific survival (HR = 3.05, 95% CI 1.91-4.86), and disease-free survival (HR = 2.12, 95% CI 1.52-2.96). The associations were not modified by race, age at diagnosis, and pre-diagnostic weight. BMI gain (> 0.5 kg/m²/year) was also related to worse survival, but the effect was weak (HR = 1.60, 95% CI 1.10-2.33 for overall survival).

CONCLUSION

BMI loss is a strong predictor of worse breast cancer outcomes. Growing prevalence of obesity may hide diagnosis of cancer cachexia, which can occur in a large proportion of breast cancer patients long before death.

Epidemiology of Triple-Negative Breast Cancer: A Review

ABSTRACT

Triple-negative breast cancer accounted for 12% of breast cancers diagnosed in the United States from 2012 to 2016, with a 5-year survival 8% to 16% lower than hormone receptor-positive disease. However, preventive and screening strategies remain tailored to the demographics of less lethal luminal cancers. This review examines the ethnic, genetic, and modifiable risk factors associated with triple-negative breast cancer, which providers must recognize to address the societal disparities of this deadly disease. Most notable is that triple-negative cancers disproportionately affect African American women and carriers of germline BRCA and PALB2 mutations. Even controlling for treatment delays, stage, and socioeconomic factors, African Americans with triple-negative breast cancer remain nearly twice as likely to die of their disease. To level the playing field, we must integrate genomic predictors of disease and epidemiologic characteristics of molecular breast cancer subtypes to provide personalized risk assessment, screening, and treatment for each patient.

Contribution of Germline Predisposition Gene Mutations to Breast Cancer Risk in African American Women

BACKGROUND

The risks of breast cancer in African American (AA) women associated with inherited mutations in breast cancer predisposition genes are not well defined. Thus, whether multigene germline hereditary cancer testing panels are applicable to this population is unknown. We assessed associations between mutations in panel-based genes and breast cancer risk in 5054 AA women with breast cancer and 4993 unaffected AA women drawn from 10 epidemiologic studies.

METHODS

Germline DNA samples were sequenced for mutations in 23 cancer predisposition genes using a QIAseq multiplex amplicon panel. Prevalence of mutations and odds ratios (ORs) for associations with breast cancer risk were estimated with adjustment for study design, age, and family history of breast cancer.

RESULTS

Pathogenic mutations were identified in 10.3% of women with estrogen receptor (ER)-negative breast cancer, 5.2% of women with ER-positive breast cancer, and 2.3% of unaffected women. Mutations in BRCA1, BRCA2, and PALB2 were associated with high risks of breast cancer (OR = 47.55, 95% confidence interval [CI] = 10.43 to >100; OR = 7.25, 95% CI = 4.07 to 14.12; OR = 8.54, 95% CI = 3.67 to 24.95, respectively). RAD51D mutations were associated with high risk of ER-negative disease (OR = 7.82, 95% CI = 1.61 to 57.42). Moderate risks were observed for CHEK2, ATM, ERCC3, and FANCC mutations with ER-positive cancer, and RECQL mutations with all breast cancer.

CONCLUSIONS

The study identifies genes that predispose to breast cancer in the AA population, demonstrates the validity of current breast cancer testing panels for use in AA women, and provides a basis for increased referral of AA patients for cancer genetic testing.

Heritable Susceptibility to Breast Cancer among African-American Women in the Detroit Research on Cancer Survivors Study

BACKGROUND

African-American women have high rates of breast cancer associated with hereditary features. However, no studies have reported the prevalence of inherited variation across all genes known to be breast cancer risk factors among African-American patients with breast cancer not selected for high-risk characteristics.

METHODS

We evaluated 182 African-American women diagnosed with invasive breast cancer in metropolitan Detroit via targeted capture and multiplex sequencing of 13 well-established breast cancer risk genes and five suggested breast cancer risk genes.

RESULTS

We identified 24 pathogenic variants in 23 women [12.6%; 95% confidence interval (CI), 8.2%-18.4%] and five genes (BRCA2, BRCA1, ATM, RAD50, CDH1). BRCA1 and BRCA2 accounted for 58.3% of all pathogenic variants. An additional six pathogenic variants were found in suggested breast cancer risk genes (MSH6, MUTYH, NF1, BRIP1).

CONCLUSIONS

The prevalence of germline pathogenic variants is relatively high among African-American patients with breast cancer unselected for high-risk characteristics across a broad spectrum of genes.

IMPACT

This study helps to define the genomic landscape of breast cancer susceptibility in African-American women who could benefit from enhanced surveillance and screening.

Genetic factors associated with cancer racial disparity - an integrative study across twenty-one cancer types

It is well known that different racial groups have significantly different incidence and mortality rates for certain cancers. It has been suggested that biological factors play a major role in these cancer racial disparities. Previous studies on the biological factors contributing to cancer racial disparity have generated a very large number of candidate factors, although there is modest agreement among the results of the different studies. Here, we performed an integrative analysis using genomic data of 21 cancer types from TCGA, GTEx, and the 1000 Genomes Project to identify biological factors contributing to racial disparity in cancer. We also built a companion website with additional results for cancer researchers to freely mine. Our study identified genes, gene families, and pathways displaying similar differential expression patterns between different racial groups across multiple cancer types. Among them, XKR9 gene expression was found to be significantly associated with overall survival for all cancers combined as well as for several individual cancers. Our results point to the interesting hypothesis that XKR9 could be a novel drug target for cancer immunotherapy. Bayesian network modeling showed that XKR9 is linked to important cancer-related genes, including FOXM1, cyclin B1, and RB1CC1 (RB1 regulator). In addition, metabolic pathways, neural signaling pathways, and several cancer-related gene families were found to be significantly associated with cancer racial disparities for multiple cancer types. Single nucleotide polymorphisms (SNPs) discovered through integrating data from the TCGA, GTEx, and 1000 Genomes databases provide biologists the opportunity to test highly promising, targeted hypotheses to gain a deeper understanding of the genetic drivers of cancer racial disparity and cancer biology in general.

Gene panel screening for insight towards breast cancer susceptibility in different ethnicities

African American breast cancer genetics is less understood compared to European American breast cancer susceptibility. Despite the many advantages of gene panel screening, studies investigating African American inherited breast cancer risk and comparing variant contributions between ethnicities are infrequent. Thus, 97 breast cancer-affected individuals of African and European descent from the Alabama Hereditary Cancer Cohort were screened using the research-based gene-panel, B.O.P. (Breast, Ovarian, and Prostate cancer). Upon sequencing and bioinformatic processing, rare coding variants in 14 cancer susceptibility genes were categorized according to the American College of Medical Genetics guidelines and compared between ethnicities. Overall, 107 different variants were identified, the majority of which were benign/likely benign. A pathogenic/likely pathogenic variant was detected in 8.6% and 6.5% of African American and European American cases, respectively, which was not statistically significant. However, African Americans were more likely to have at least one variant of uncertain significance (VUS; p-value 0.006); they also had significantly more VUSs in BRCA1/2 compared to European Americans (p-value 0.015). Additionally, 51.4% of African Americans and 32.3% of European Americans harbored multiple rare variants, and African Americans were more likely to have at least one VUS and one benign/likely benign variant (p-value 0.032), as well as multiple benign/likely benign variants (p-value 0.089). Moreover, of the 15 variants detected in multiple breast cancer cases, ATM c.2289T>C (p.F763L), a VUS, along with two likely benign variants, BRCA2 c.2926_2927delinsAT (p.S976I) and RAD51D c.251T>A (p.L84H), were determined to be associated with African American breast cancer risk when compared to ethnic-specific controls. Ultimately, B.O.P. screening provides essential insight towards the variant contributions in clinically relevant cancer susceptibility genes and differences between ethnicities, stressing the need for future research to elucidate inherited breast cancer risk.

Understanding breast cancer disparities-a multi-scale challenge

Despite convergence of overall breast cancer incidence rates between European American (EA) and African American (AA) women, disparities in mortality persist. The factors contributing to differences in mortality rates across population groups remain controversial and range from population genetics to sociodemographic influences. This review explores the complex multi-factorial nature of tumor-intrinsic and -extrinsic factors that impact the biology and clinical outcomes of breast cancer patients. In addition to summarizing the current state of breast cancer disparities research, we also motivate the development of integrative multi-scale approaches involving interdisciplinary teams to tackle this complex clinical challenge.

Is there a duty to reinterpret genetic data? The ethical dimensions

The evolving evidence base for the interpretation of variants identified in genetic and genomic testing has presented the genetics community with the challenge of variant reinterpretation. In particular, it is unclear whether an ethical duty of periodic reinterpretation should exist, who should bear that duty, and what its dimensions should be. Based on an analysis of the ethical arguments for and against a duty to reinterpret, we conclude that a duty should be recognized. Most importantly, by virtue of ordering and conducting tests likely to produce data on variants that cannot be definitively interpreted today, the health-care system incurs a duty to reinterpret when more reliable data become available. We identify four elements of the proposed ethical duty: data storage, initiation of reinterpretation, conduct of reinterpretation, and patient recontact, and we identify the parties best situated to implement each component. We also consider the reasonable extent and duration of a duty, and the role of the patient's consent in the process, although we acknowledge that some details regarding procedures and funding still need to be addressed. The likelihood of substantial patient benefit from a systematic approach to reinterpretation suggests the importance for the genetics community to reach consensus on this issue.

Prevalence of Inherited Mutations in Breast Cancer Predisposition Genes among Women in Uganda and Cameroon

BACKGROUND

Sub-Saharan Africa (SSA) has a high proportion of premenopausal hormone receptor negative breast cancer. Previous studies reported a strikingly high prevalence of germline mutations in BRCA1 and BRCA2 among Nigerian patients with breast cancer. It is unknown if this exists in other SSA countries.

METHODS

Breast cancer cases, unselected for age at diagnosis and family history, were recruited from tertiary hospitals in Kampala, Uganda and Yaoundé, Cameroon. Controls were women without breast cancer recruited from the same hospitals and age-matched to cases. A multigene sequencing panel was used to test for germline mutations.

RESULTS

There were 196 cases and 185 controls with a mean age of 46.2 and 46.6 years for cases and controls, respectively. Among cases, 15.8% carried a pathogenic or likely pathogenic mutation in a breast cancer susceptibility gene: 5.6% in BRCA1, 5.6% in BRCA2, 1.5% in ATM, 1% in PALB2, 0.5% in BARD1, 0.5% in CDH1, and 0.5% in TP53. Among controls, 1.6% carried a mutation in one of these genes. Cases were 11-fold more likely to carry a mutation compared with controls (OR = 11.34; 95% confidence interval, 3.44-59.06; P < 0.001). The mean age of cases with BRCA1 mutations was 38.3 years compared with 46.7 years among other cases without such mutations (P = 0.03).

CONCLUSIONS

Our findings replicate the earlier report of a high proportion of mutations in BRCA1/2 among patients with symptomatic breast cancer in SSA.

IMPACT

Given the high burden of inherited breast cancer in SSA countries, genetic risk assessment could be integrated into national cancer control plans.

Regarding the Yin and Yang of Precision Cancer- Screening and Treatment: Are We Creating a Neglected Majority?

In this commentary, we submit that the current emphasis of precision cancer screening and treatment (PCST) has been to provide and interpret the implications of "positive" screening results for those deemed to be at greatest risk for cancer or most likely to benefit from targeted treatments. This is an important, but proportionately small target group, regardless of the cancer context. Overlooked by this focus is the larger majority of those screened who receive "negative" results. We contend that for optimal dissemination of PCST, the complement of positive and negative results be viewed as an inseparable yin-yang duality with the needs of those who receive negative screening results viewed as important as those deemed to be at highest risk or derive targeted treatment benefit. We describe three areas where communication of negative PCST results warrant particular attention and research consideration: population-based family history screening, germline testing for hereditary cancer syndromes, and tumor testing for targeted cancer treatment decision-making. Without thoughtful consideration of the potential for negative results to have psychological and behavioral influences, there is a potential to create a "neglected majority". This majority may be inclined to misinterpret results, disseminate inaccurate information to family, dismiss the credibility of results, or become disillusioned with existing medical treatments.

BRCA1 and BRCA2 pathogenic sequence variants in women of African origin or ancestry

BRCA1 and BRCA2 (BRCA1/2) pathogenic sequence variants (PSVs) confer elevated risks of multiple cancers. However, most BRCA1/2 PSVs reports focus on European ancestry individuals. Knowledge of the PSV distribution in African descent individuals is poorly understood. We undertook a systematic review of the published literature and publicly available databases reporting BRCA1/2 PSVs also accessed the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) database to identify African or African descent individuals. Using these data, we inferred which of the BRCA PSVs were likely to be of African continental origin. Of the 43,817 BRCA1/2 PSV carriers in the CIMBA database, 469 (1%) were of African descent. Additional African descent individuals were identified in public databases (n = 291) and the literature (n = 601). We identified 164 unique BRCA1 and 173 unique BRCA2 PSVs in individuals of African ancestry. Of these, 83 BRCA1 and 91 BRCA2 PSVs are of likely or possible African origin. We observed numerous differences in the distribution of PSV type and function in African origin versus non-African origin PSVs. Research in populations of African ancestry with BRCA1/2 PSVs is needed to provide the information needed for clinical management and decision-making in African descent individuals worldwide.

The role of BRCA1/2 in hereditary and familial breast and ovarian cancers

BACKGROUND

BRCA1/2 pathogenic variants have become associated with familial breast and ovarian cancers, and hereditary cancer-predisposition syndrome. With advances in molecular biology, BRCA profiling facilitates early diagnosis and the implementation of preventive and therapeutic strategies. The genes exhibit variable prevalence among different individuals and moderate interpretation complexity. BRCA deficiency is instrumental in cancer development, affects therapeutic options and is instrumental in drug resistance. In addition, BRCA1/2 profile is diverse across different groups and has been associated with the "founder effect" in certain populations.

METHODS

In this review, we aim to detail the spectrum of BRCA1/2 variants and their associated risk estimates.

RESULTS

The relationship between BRCA1/2 and hereditary and familial cancers is indisputable, yet BRCA screening methods are beset with limitations and lack clinical confidence.

CONCLUSION

This review emphasizes the importance of screening BRCA genetics, in addition to their clinical utility. Furthermore, founder variants are anticipated in the Saudi population.

Assessing the effectiveness of the National Comprehensive Cancer Network genetic testing guidelines in identifying African American breast cancer patients with deleterious genetic mutations

PURPOSE

Approximately, 10% of breast cancers are hereditary. Identifying women at high risk for hereditary breast and ovarian cancer allows for early detection, prevention, and individualized disease management for those diagnosed with breast cancer. There is limited data about breast cancer genetic risks among African Americans as the majority of the large studies have been conducted in European Americans. We examined the distribution of deleterious genetic mutations in African American breast cancer patients, and evaluated the effectiveness of the National Comprehensive Cancer Network (NCCN) guidelines for identifying African American women at high risk for deleterious genetic mutations.

METHODS

African American participants with breast cancer underwent an interview regarding health and family history, and a 30-gene saliva test. Medical records were accessed to determine whether participants had received prior genetic testing as part of usual care, results of previous testing, and cancer characteristics.

RESULTS

Two hundred and fifty participants were enrolled between February 2016 and May 2018. Twenty (8.0%) had a deleterious mutation in one of the 30 genes; BRCA2 had the highest frequency (40.0%). 187 (74.8%) met eligibility for testing based on NCCN guidelines. Only 110 (58.8%) of participants eligible for genetic testing, according to guidelines, had received prior testing as part of routine care. Using the 30-gene test, we identified deleterious mutations in 17 of 187 (9.1%) of those who met NCCN criteria for testing, and three of 63 (4.8%) of those who did not meet criteria for testing nonetheless had a deleterious mutation associated with breast cancer.

CONCLUSIONS

Our results indicate that a large proportion of African American breast cancer patients who meet criteria for genetic testing do not receive it as part of routine care. Even in women who do not meet testing guidelines, nearly 5% have a known deleterious mutation associated with breast cancer.

MRI in the Early Detection of Breast Cancer in Women with High Genetic Risk

Aims and background

Women with BRCA1 or BRCA2 germline mutations have an elevated risk of developing breast and/or ovarian cancer. Because of the early onset of the disease, screening of this group of women should start at an earlier age than in the general population. The association of breast magnetic resonance imaging (BMRI) and ultrasonography (US) with mammography (MX) and clinical breast examination (CBE) in the regular surveillance of these individuals has been proposed and seems to improve the early detection of breast cancer.

Methods

Within a multicenter study started by the Istituto Superiore di Sanita (Rome), at the Istituto Nazionale Tumori of Milan (INT) we enrolled 116 women at high genetic risk for breast cancer; they were either BRCA1 or BRCA2 mutation carriers or had a strong family history of breast cancer. They underwent CBE, MX, US and BMRI once a year.

Results

Between June 2000 and April 2005, at INT 12 cancers were detected among the 116 screened individuals (10%). In this subgroup, 1 patient refused BMRI and in 2 cases US was not performed. With BMRI we found 11 cancers and 6 of them were detectable only by this technique. In these 6 cases, the size of the disease was less than 1 cm and MX was false negative due to irregularly nodular parenchyma in 4 cases and scar tissue or prosthesis in the other 2. US was not performed in 2 cases and was false negative in 4 cases. Three false positive results were found with BMRI: 1 case was considered suspect but related to hormonal influences; 1 case with the same pattern was sent for second-look US, which gave a negative result and BMRI review after 6 months showed normalization of the parenchyma; in the third case histology revealed the presence of adenosis. No false positive results were registered for MX.

Conclusions

The aim of secondary prevention is the detection of cancer at its earliest stage. BMRI screening in women with BRCA1 or BRCA2 mutations or at high familiar risk appears to be highly sensitive and may detect mammographically occult disease. The accuracy of MR imaging is higher than that of conventional imaging but the technique is flawed by a lower specificity. In order to avoid unnecessary biopsies we believe that the combination of BMRI and conventional imaging can be very useful in screening women with a high genetic risk of breast cancer, especially with second-look evaluation by means of US when BMRI yields the only positive diagnostic result. Second-look US has been demonstrated to be of critical importance both in recognizing false positive BMRI results and in guiding biopsies, when necessary.