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

Attitudes of African Americans toward return of results from exome and whole genome sequencing

Exome sequencing and whole genome sequencing (ES/WGS) present patients and research participants with the opportunity to benefit from a broad scope of genetic results of clinical and personal utility. Yet, this potential for benefit also risks disenfranchising populations such as African Americans (AAs) that are already underrepresented in genetic research and utilize genetic tests at lower rates than other populations. Understanding a diverse range of perspectives on consenting for ES/WGS and receiving ES/WGS results is necessary to ensure parity in genomic health care and research. We conducted a series of 13 focus groups (n = 76) to investigate if and how attitudes toward participation in ES/WGS research and return of results from ES/WGS differ between self-described AAs and non-AAs. The majority of both AAs and non-AAs were willing to participate in WGS studies and receive individual genetic results, but the fraction not interested in either was higher in AAs. This is due in part to different expectations of health benefits from ES/WGS and how results should be managed. Our results underscore the need to develop and test culturally tailored strategies for returning ES/WGS results to AAs.

Ancestry, Temporality, and Potentiality: Engaging Cancer Genetics in Southern Brazil

In this paper I examine the variety of ways potential is articulated, entailed, and produced in how the field of cancer genetics is being constituted as a domain of transnational research and an emerging site of health-care intervention in southern Brazil. Drawing on analysis of fieldwork in Brazilian cancer-genetics clinics, I explore how different expressions of potential come to inform dynamically the pursuit of prevention, care, and research as diversely scaled investments for those working and living with cancer-genetics knowledge and technologies. It illustrates how specific temporalities help to constitute and "abductively" frame the meaning of these different potentials particularly as this relates to a focus on ancestry. Colonial histories of migration, the embodied effects of dietary habits, or the moral failings of near and distant ancestors as well as promissory futures and the contingency of lived lives become at different times templates for identifying, materializing, and transforming how the potential of cancer genetics in Brazil is articulated. Potential is also expressed through an idiom of "choice" in different efforts to situate participation in cancer-genetics research as prevention or to negotiate access to basic public health. I explore how these expressions of cancer genetics as potential powerfully yet unevenly work to sustain knowledge practices as well as propel patients and their families into fledgling domains of clinical practice and scientific research. At the same time there is always an "excess of meaning" in these endeavors that make visible lines of fracture and disjuncture in collective efforts to make future histories of and from the pursuit of cancer genetics in southern Brazil.

Genetic counselling in post-genomic era-to be or not to be

With the surge of genetic tests and technologies, genetic counsellors are faced with the challenge of translating emerging scientific knowledge into practical information for patients, clinicians and public health policy makers. The new tests and technologies also are associated with new psychosocial and ethical considerations. New guidelines are needed for each new discovery of the genomic impact on phenotype, pathology and disease while “old” syndromes and “old” pathology, continue to require attention. In the new post-Human Genome Project era, genetic counsellors will be an integral part of translating genomic discoveries into beneficial impact on human disease, health care, and medical benefits. The needs for genetic counselling should be designed into genomic research at the onset. Genetic counsellors need to handle old while rapidly assimilating new information and the principal challenge is to be up to date and updated.

Psychosocial approaches to participation in BRCA1/2 genetic risk assessment among African American women: a systematic review

Breast cancer is a significant health concern for African American women. Nonetheless, uptake of genetic risk assessment (including both genetic counseling and testing) for breast cancer gene mutations among these populations remains low. This paper systematically reviews cognitive (i.e., beliefs) and affective (i.e., emotions) factors influencing BRCA1/2 genetic risk assessment among African American women as well as psychosocial interventions to facilitate informed decision making in this population. A systematic search of CINAHL, PubMed, and PsycINFO was undertaken, yielding 112 published studies. Of these, 18 met the eligibility criteria. African American woman are likely to participate in genetic risk assessment if they are knowledgeable about cancer genetics, perceive a high risk of developing breast cancer, have low expectancies of stigmatization from medical professionals, view themselves as independent from family, and have fatalistic beliefs and a future temporal orientation. Anticipated negative affective responses, such as an inability to “handle” the results of testing, are barriers to uptake. Specific perceptions, beliefs, and emotional factors are associated with genetic risk assessment among African American women. Understanding these factors is key in the development of interventions to facilitate informed decision making in this population.

Outcomes of a systems-level intervention offering breast cancer risk assessments to low-income underserved women

Hereditary breast and ovarian cancer risk assessments (CRAs) are underutilized by low-income and racial/ethnic minority women, potentially exacerbating cancer-related disparities observed within these populations. We deployed and evaluated a systems-level intervention designed to identify patients potentially at-risk for hereditary breast/ovarian cancer, refer them for CRAs, and facilitate CRA utilization at an urban community-based breast health care center. Cancer family history forms were completed by patients seen at the center during an 18-month period and reviewed by staff for CRA eligibility against published referral criteria. A patient navigator educated eligible patients about the benefits of CRA, navigating interested patients to this service. CRA-specific patient interest and utilization outcomes are reported. In total, 94.7 % of all patients (n = 2,436) completed forms and 65 patients (2.7 %) met CRA eligibility criteria. Most eligible patients (72.3 %) were interested in CRA. Interested patients had a greater risk for hereditary breast/ovarian cancer (i.e., more affected relatives, greater objective risk scores) than uninterested patients: 57.4 % scheduled a CRA appointment and 51.9 % of scheduled patients utilized CRAs. Patients scheduling a CRA were contacted in less time and required fewer follow-up contacts by the patient navigator, and were more likely to be African American, than those who declined a CRA or were lost to follow-up (all p's ≤ .05). The systems-level intervention successfully identified patients eligible for CRA and linked interested and at-risk patients with CRA resources. More intensive patient navigation addressing the unique barriers encountered within this population may be required to enhance utilization.

BRCA1/2 sequence variants of uncertain significance: a primer for providers to assist in discussions and in medical management

INTRODUCTION

DNA variants of uncertain significance (VUS) are common outcomes of clinical genetic testing for susceptibility to cancer. A statistically rigorous model that provides a pathogenicity score for each variant has been developed to aid in the clinical management of patients undergoing genetic testing.

METHODS

The information in this article is derived from multiple publications on VUS in BRCA genes, distilled for communicating with clinicians who may encounter VUS in their practice.

RESULTS

The posterior probability scores for BRCA1 or BRCA2 VUS, calculated from a multifactorial likelihood model, are explained, and links for looking up specific VUS are provided. The International Agency on Cancer Research (IARC) of the World Health Organization has proposed a simple five-tier system for clinical management that is not widely known to clinicians. Classes 1 and 2 in this system are managed as neutral variants, classes 4 and 5 are managed as pathogenic variants, and class 3 variants still have insufficient evidence to move to either end of this scale and, thus, cannot be used in medical management.

CONCLUSIONS

Development of models that integrate multiple independent lines of evidence has allowed classification of a growing number of VUS in the BRCA1 and BRCA2 genes. The pathogenicity score that is generated by this model maps to the IARC system for clinical management, which will assist clinicians in the medical management of those patients who obtain a VUS result upon testing.

Ethnic disparities in breast cancer

Breast cancer is the leading cause of cancer death for women worldwide. While breast cancer incidence is lower for many ethnic minority women than for white women, stage at diagnosis and survival are often worse. These disparities are most marked for African-American women, but are also present for Asians, Latinas, Native Americans and Hawaiians. The etiology of ethnic disparities in breast cancer is multifactorial, including differences in tumor characteristics, genetics, access to care and insurance, prevalence of risk factors, screening participation and processes of care, such as timeliness of diagnosis and quality of communication and treatment. This review will examine what is known regarding ethnic differences in all of these areas, what questions remain, and where researchers and policy makers should focus their future efforts.

Low rates of African American participation in genetic counseling and testing for BRCA1/2 mutations: racial disparities or just a difference?

Low rates of genetic counseling among African American women have generated concerns about disparities; however, to the extent that women's decisions to accept or decline counseling are consistent with their values, then lower participation may reflect preferences and not disparities. We evaluated the extent to which women were satisfied with their decision about participating in genetic counseling for BRCA1/2 mutations and identified variables that were associated significantly with satisfaction. Prospective study of decision satisfaction with 135 African American women who had a minimum 5% prior probability of having a BRCA1/2 mutation. Decision satisfaction was evaluated one month after women were offered participation in genetic counseling using a structured questionnaire. Women were satisfied with their participation decision; more than 80% reported that their decision was consistent with their family values. However, women who declined pre-test counseling had significantly lower satisfaction scores. Our findings highlight the importance ensuring that racial differences that are due to preferences and values are not misclassified as disparities in order to identify and address the root causes of disparate treatment.

Identification of BRCA1/2 founder mutations in Southern Chinese breast cancer patients using gene sequencing and high resolution DNA melting analysis

BACKGROUND

Ethnic variations in breast cancer epidemiology and genetics have necessitated investigation of the spectra of BRCA1 and BRCA2 mutations in different populations. Knowledge of BRCA mutations in Chinese populations is still largely unknown. We conducted a multi-center study to characterize the spectra of BRCA mutations in Chinese breast and ovarian cancer patients from Southern China.

METHODOLOGY/PRINCIPAL FINDINGS

A total of 651 clinically high-risk breast and/or ovarian cancer patients were recruited from the Hong Kong Hereditary Breast Cancer Family Registry from 2007 to 2011. Comprehensive BRCA1 and BRCA2 mutation screening was performed using bi-directional sequencing of all coding exons of BRCA1 and BRCA2. Sequencing results were confirmed by in-house developed full high resolution DNA melting (HRM) analysis. Among the 451 probands analyzed, 69 (15.3%) deleterious BRCA mutations were identified, comprising 29 in BRCA1 and 40 in BRCA2. The four recurrent BRCA1 mutations (c.470_471delCT, c.3342_3345delAGAA, c.5406+1_5406+3delGTA and c.981_982delAT) accounted for 34.5% (10/29) of all BRCA1 mutations in this cohort. The four recurrent BRCA2 mutations (c.2808_2811delACAA, c.3109C>T, c.7436_7805del370 and c.9097_9098insA) accounted for 40% (16/40) of all BRCA2 mutations. Haplotype analysis was performed to confirm 1 BRCA1 and 3 BRCA2 mutations are putative founder mutations. Rapid HRM mutation screening for a panel of the founder mutations were developed and validated.

CONCLUSION

In this study, our findings suggest that BRCA mutations account for a substantial proportion of hereditary breast/ovarian cancer in Southern Chinese population. Knowing the spectrum and frequency of the founder mutations in this population will assist in the development of a cost-effective rapid screening assay, which in turn facilitates genetic counseling and testing for the purpose of cancer risk assessment.

Identification of the prevalent BRCA1 and BRCA2 mutations in the female population of Puerto Rico

Mutations in the breast cancer 1, early onset (BRCA1) and breast cancer 2 (BRCA2) genes are responsible for the majority of hereditary breast cancers. Knowledge of the incidence and prevalence of BRCA mutations in a specific population or ethnic group is necessary to provide accurate genetic counseling for breast cancer patients and their families; however, these data have not been gathered in the population of Puerto Rico. We conducted a retrospective study of female breast cancer patients undergoing genetic testing for BRCA mutations in the highest-volume breast surgery practices in San Juan, Puerto Rico. Data collection includes three-generation family cancer history and results from complete BRCA sequencing. A total of six different deleterious mutations were observed, including one mutation in BRCA1 and five mutations in BRCA2. Three recurrent mutations (BRCA1 del exon1-2, BRCA2 4150G>T, and BRCA2 6027del4) account for over 70% of all the BRCA mutations observed in this study population. This study examines for the first time the characteristics of hereditary breast cancer in Puerto Rico and assesses the accuracy of existing genetic risk assessment tools in that population. This data is expected to contribute to providing accurate and efficient tools for the clinical management of hereditary breast cancer in Puerto Rico.

Accuracy of BRCA1/2 mutation prediction models for different ethnicities and genders: experience in a southern Chinese cohort

Background

BRCA1/2 mutation prediction models (BRCAPRO, Myriad II, Couch, Shattuck-Eidens, BOADICEA) are well established in western cohorts to estimate the probability of BRCA1/2 mutations. Results are conflicting in Asian populations. Most studies did not account for gender-specific prediction. We evaluated the performance of these models in a Chinese cohort, including males, before BRCA1/2 mutation testing.

Methods

The five risk models were used to calculate the probability of BRCA mutations in probands with breast and ovarian cancers; 267 were non-BRCA mutation carriers (247 females and 20 males) and 43 were BRCA mutation carriers (38 females and 5 males).

Results

Mean BRCA prediction scores for all models were statistically better for carriers than noncarriers for females but not for males. BRCAPRO overestimated the numbers of female BRCA1/2 mutation carriers at thresholds ≥20% but underestimated if <20%. BRCAPRO and BOADICEA underestimated the number of male BRCA1/2 mutation carriers whilst Myriad II underestimated the number of both male and female carriers. In females, BRCAPRO showed similar discrimination, as measured by the area under the receiver operator characteristic curve (AUC) for BRCA1/2 combined mutation prediction to BOADICEA, but performed better than BOADICEA in BRCA1 mutation prediction (AUC 93% vs. 87%). BOADICEA had the best discrimination for BRCA1/2 combined mutation prediction (AUC 87%) in males.

Conclusions

The variation in model performance underscores the need for research on larger Asian cohorts as prediction models, and the possible need for customizing these models for different ethnic groups and genders.

Hidden dangers: a cryptic exon disrupts BRCA2 mRNA

The first mutation that disrupts BRCA2 mRNA by including a novel, cryptic exon is reported in this issue. The mutation lies deep within an intron and would not have been detected by conventional screening methods. In the future, more mutations may be discovered by direct mRNA analysis.

A guide for functional analysis of BRCA1 variants of uncertain significance

Germline mutations in the tumor suppressor gene BRCA1 confer an estimated lifetime risk of 56-80% for breast cancer and 15-60% for ovarian cancer. Since the mid 1990s when BRCA1 was identified, genetic testing has revealed over 1,500 unique germline variants. However, for a significant number of these variants, the effect on protein function is unknown making it difficult to infer the consequences on risks of breast and ovarian cancers. Thus, many individuals undergoing genetic testing for BRCA1 mutations receive test results reporting a variant of uncertain clinical significance (VUS), leading to issues in risk assessment, counseling, and preventive care. Here, we describe functional assays for BRCA1 to directly or indirectly assess the impact of a variant on protein conformation or function and how these results can be used to complement genetic data to classify a VUS as to its clinical significance. Importantly, these methods may provide a framework for genome-wide pathogenicity assignment.

Characteristics and spectrum of BRCA1 and BRCA2 mutations in 3,922 Korean patients with breast and ovarian cancer

This investigation is aimed at evaluating the epidemiologic characteristics of BRCA1/2 germline mutations in Korean patients with breast and ovarian cancer (BOC). We analyzed the entire mutational data of BRCA1/2 genes in BOC patients who were tested in Korea since the first Korean report of BRCA1 mutation in 1995 with the exception of the data covered in the Korean Hereditary Breast Cancer (KOHBRA) study, the project launched in 2007 for establishing BRCA1/2 carrier cohorts in Korea. In total, BRCA1/2 gene mutations of 3,922 Korean BOC patients were evaluated, including the unpublished data of 2,139 breast cancer patients examined by four Korean institutions and the data of 1,783 BOC patients covered in ten previous reports. Overall, 420 (150 distinct) pathogenic mutations were identified, 211 (73 distinct) in BRCA1 and 209 (77 distinct) in BRCA2. The majority (134 of 150) of the distinct mutations resulted in premature termination codon of the BRCA1/2 translation. BRCA1 c.4186-1593_4676-1465del was the only large genomic rearrangements mutation. Out of 150 distinct BRCA1/2 mutations, 84 (56 %) mutations were considered specific to Korean BOC. Eighty-five BRCA1/2 mutations were detected in at least two unrelated patients. These recurrent mutations account for 84.5 % (355 of 420) of mutations detected in the Korean population. In the pooled mutational data of BRCA1/2 genes, this study discovered the prevalence of BRCA1/2 mutations in the Korean BOC patients is similar to those found in other ethnic groups. Large genomic rearrangements in BRCA1/2 genes were infrequently detected among the Korean patients with BOC. There were several BRCA1/2 mutation candidates for founder mutations. To further establish a Korean cohort for BRCA1/2 mutations, the nationwide KOHBRA study is in progress.

Translational advances regarding hereditary breast cancer syndromes

Approximately 5-10% of breast cancers may be inheritable, up to 90% of which are due to mutations in BRCA1 and BRCA2. A substantial minority are caused by non-BRCA mutations, such as TP53, PTEN, STK11, CHEK2, ATM, BRIP1, and PALB2 mutations. This review highlights translational research advances with regard to the development of probabilistic models for hereditary breast cancer syndromes, the identification of specific genetic mutations responsible for these syndromes, as well as their testing and interpretations.

'Cancer doesn't have an age': genetic testing and cancer risk management in BRCA1/2 mutation-positive women aged 18-24

Increasingly, 18-24-year-old women from hereditary breast/ovarian cancer (HBOC) families are pursuing genetic testing, despite their low absolute risks of breast and ovarian cancer and the fact that evidence-based management options used with older high-risk women are not generally available. Difficult clinical decisions in older carriers take on substantially more complexity and value-laden import in very young carriers. As a result, many of the latter receive highly personal and emotionally charged cancer risk information in a life context where management strategies are not well defined. We analyzed 32 in-depth interviews with BRCA1/2 mutation-positive women aged 18-24 using techniques of grounded theory and interpretive description. Participants described feeling vulnerable to a cancer diagnosis but in a quandary regarding their care because evidence-based approaches to management have not been developed and clinical trials have not been undertaken. Our participants demonstrated a wide range of genetic and health literacy. Inconsistent recommendations, surveillance fatigue, and the unpredictability of their having health insurance coverage for surgical risk-reducing procedures led several to contemplate risk-reducing mastectomy before age 25. Parents remained a primary source of emotional and financial support, slowing age-appropriate independence and complicating patient privacy. Our findings suggest that, for 18-24-year-olds, readiness to autonomously elect genetic testing, to fully understand and act on genetic information, and to confidently make decisions with life-long implications are all evolving processes. We comment on the tensions between informed consent, privacy, and the unique developmental needs of BRCA1/2 mutation-positive women just emerging into their adult years.

Follow-up of carriers of BRCA1 and BRCA2 variants of unknown significance: variant reclassification and surgical decisions

PURPOSE

: Approximately 5-10% of patients who undergo genetic testing of BRCA1 and BRCA2 receive a variant of unknown significance (VUS) result. The ambiguous nature of a VUS may increase difficulty in patient understanding and decision making regarding risk reduction and surveillance options, including cancer risk-reducing surgeries. VUS reclassification to benign or deleterious may occur in time; however, clinical decisions may need to be made expeditiously, and some patients may pursue irreversible treatments before VUS reclassification.

METHODS

: We reviewed the surgical decisions of 107 women postdisclosure of a BRCA VUS result counseled at our institute between 1998 and 2009.

CONCLUSION

: Among women receiving a BRCA VUS result at our center, 11 of 107 (10.3%) pursued cancer risk-reducing mastectomy and 22 of 107 (20.6%) pursued cancer risk-reducing bilateral salpingo-oophorectomy. Reclassification of VUS occurred up to 9 years after testing, and 5 of 22 (22.7%) women followed up for 8 or more years continue to have a VUS result. We discuss considerations for providers of genetic services to discuss with patients who receive a VUS result.

Ethical dimensions of disparities in depression research and treatment in the pharmacogenomic era

Disparities in access to, and utilization of, treatment for depression among African-American and Caucasian elderly adults have been well-documented. Less fully explored are the multidimensional factors responsible for these disparities. The intersection of cultural constructs, socioeconomic factors, multiple levels of racism, and stigma attending both mental health issues and older age may help to explain disparities in the treatment of the depressed elderly. Personalized medicine with its promise of developing interventions tailored to an individual's health needs and genetically related response to treatment might seem a promising antidote to the documented underutilization of standard depression treatments by African Americans. However, this paper examines the multidimensional factors associated with disparities in effective treatment of depression among African-American and Caucasian elderly adults and argues the scientific and ethical importance of pursuing various paths to address multiple levels and sources of stigma and mistrust if pharmacogenomics is to help, rather than exacerbate, disparities in depression treatment. Seven recommendations are offered to increase the likelihood that developments in pharmacogenomics will reduce disparities in depression treatment.

Providers' perceptions and practices regarding BRCA1/2 genetic counseling and testing in African American women

We examined healthcare providers' perceptions of genetic counseling and testing in African American women at moderate to high-risk of carrying a BRCA1/2 mutation. We conducted 20 in-depth interviews with genetic counselors (n = 5), medical oncologists (n = 8), obstetrician/gynecologists (n = 2) and surgeons (n = 5). Interviews were audiotaped, transcribed and independently coded by two individuals using a content analysis approach. Seven themes emerged relevant to providers' perceptions of African American women's use of BRCA1/2 genetic services: access factors, cultural beliefs and preferences, effects of testing, patient motivators for genetic counseling and testing, patient-provider communication, reasons for provider referral, and reasons for patient refusal. Providers identified individual- and system-level barriers to African American women's use of genetic services, including lack of follow-up after referrals to genetic specialists and challenges to obtaining financial coverage for under- and uninsured high-risk women. Results have implications for physician and patient education regarding appropriate referrals to and uptake of genetic services in at-risk African American women.

Novel BRCA1 deleterious mutation (c.1949_1950delTA) in a woman of Senegalese descent with triple-negative early-onset breast cancer

Limited information exists regarding BRCA1 and BRCA2 genetic testing and genetic diversity in BRCA1 and BRCA2 in sub-Saharan African populations. We report a novel mutation that consists of a deletion of 2 bp (c.1949_1950delTA) in the exon 11 of the BRCA1 gene. This is a frameshift mutation that causes the disruption of the translational reading frame resulting in a premature stop codon downstream in the BRCA1 protein. The mutation was present in a Senegalese woman with a triple-negative breast tumor and a family history of breast cancer.

A computational method to classify variants of uncertain significance using functional assay data with application to BRCA1

BACKGROUND

Besides revealing cancer predisposition variants or the absence of any changes, genetic testing for cancer predisposition genes can also identify variants of uncertain clinical significance (VUS). Classifying VUSs is a pressing problem, as ever more patients seek genetic testing for disease syndromes and receive noninformative results from those tests. In cases such as the breast and ovarian cancer syndrome in which prophylactic options can be severe and life changing, having information on the disease relevance of the VUS that a patient harbors can be critical.

METHODS

We describe a computational approach for inferring the disease relevance of VUSs in disease genes from data derived from an in vitro functional assay. It is based on a Bayesian hierarchical model that accounts for sources of experimental heterogeneity.

RESULTS

The functional data correlate well with the pathogenicity of BRCA1 BRCT VUSs, thus providing evidence regarding pathogenicity when family and genetic data are absent or uninformative.

CONCLUSIONS

We show the utility of the model by using it to classify 76 VUSs located in the BRCT region of BRCA1. The approach is both sensitive and specific when evaluated on variants previously classified using independent sources of data. Although the functional data are very informative, they will need to be combined with other forms of data to meet the more stringent requirements of clinical application.

IMPACT

Our work will lead to improved classification of VUSs and will aid in the clinical decision making of their carriers.

A 3'-untranslated region KRAS variant and triple-negative breast cancer: a case-control and genetic analysis

BACKGROUND

We previously identified a functional variant in a let-7 microRNA (miRNA) complementary site in the 3'-untranslated region of the KRAS oncogene (rs61764370) which is associated with cancer. We aimed to investigate the association of this KRAS variant with breast cancer and tumour biology.

METHODS

We assessed frequency distributions of the KRAS variant in 415 patients with histologically confirmed breast cancer and 457 controls from Connecticut, USA (study group 1) and association of this variant with breast-cancer subtypes in 690 Irish women with known oestrogen receptor (ER), progesterone receptor (PR), and HER2 statuses, and 360 controls (study group 2). We pooled data for study groups 1 and 2 with a cohort of 140 women with triple-negative breast cancer and 113 controls to assess the association of the KRAS variant with triple-negative breast cancer risk, and genome-wide mRNA and specific miRNA expression in patients with triple-negative breast cancer.

FINDINGS

Although frequency distributions of the KRAS variant in study group 1 did not differ between all genotyped individuals, eight (33%) of 24 premenopausal women with ER/PR-negative cancer had the KRAS variant, compared with 27 (13%) of 201 premenopausal controls (p=0.015). In study group 2, the KRAS variant was significantly enriched in women with triple-negative breast cancer (19 [21%] of 90 cases) compared with 64 (13%) of 478 for luminal A, 13 (15%) of 87 for luminal B, and two (6%) of 35 for HER2-positive subgroups (p=0.044). Multivariate analysis in the pooled study groups showed that the KRAS variant was associated with triple-negative breast cancer in premenopausal women (odds ratio 2.307, 95% CI 1.261-4.219, p=0.0067). Gene-expression analysis of triple-negative breast-cancer tumours suggested that KRAS-variant positive tumours have significantly altered gene expression, and are enriched for the luminal progenitor and BRCA1 deficiency signatures. miRNA analysis suggested reduced levels of let-7 miRNA species in KRAS-variant tumours.

INTERPRETATION

The KRAS variant might be a genetic marker for development of triple-negative breast cancer in premenopausal women, and altered gene and miRNA expression signatures should enable molecular and biological stratification of patients with this subgroup of breast cancer.

FUNDING

US National Institutes of Health.

Breast cancer racial disparities: unanswered questions

Breast cancer is the most common noncutaneous cancer diagnosed in women in the United States and is second only to lung cancer as the leading cause of cancer-related mortality. Although mortality rates have been dropping steadily due to a variety of factors including improved treatment modalities and screening, substantial racial differences in outcome between blacks and whites persist. Although differences in health care utilization and access, tumor biology, and cancer management have been elucidated as possible reasons for disparities seen, it is likely that other interactions exist. The purpose of this review is, therefore, to present a comprehensive overview of the literature on racial disparities in breast cancer outcome and highlight potential causative factors that may contribute to disparities seen among blacks and whites with breast cancer. In addition, we make research recommendations by discussing some of the remaining gaps in knowledge that may lead to further understanding of disparities and consequently improved outcomes for all women with breast cancer.

Outcomes in black patients with early breast cancer treated with breast conservation therapy

BACKGROUND

The race-specific impact of prognostic variables for early breast cancer is unknown for black patients undergoing breast conservation.

METHODS AND MATERIALS

This was a retrospective study of 1,231 consecutive patients ≥40 years of age with Stage I-II invasive breast cancer treated with lumpectomy and radiation therapy at the University of Chicago Hospitals and affiliates between 1986 and 2004. Patients were classified as either black or nonblack. Cox proportional hazards regression was used to model the effects of known prognostic factors and interactions with race.

RESULTS

Median follow-up for surviving patients was 82 months. Thirty-four percent of patients were black, and 66% were nonblack (Caucasian, Hispanic, and Asian). Black patients had a poorer 10-year overall survival (64.6% vs. 80.8%; adjusted hazard ratio [HR], 1.59; 95% confidence interval [CI], 1.23-2.06) and 10-year disease-free survival (58.1% vs. 75.4%; HR 1.49; 95% CI, 1.18-1.89) compared with nonblack patients. Tumor sizes were similar between nonblack and black patients with mammographically detected tumors (1.29 cm vs. 1.20 cm, p = 0.20, respectively). Tumor size was significantly associated with overall survival (HR 1.48; 95% CI, 1.12-1.96) in black patients with mammographically detected tumors but not in nonblack patients (HR 1.09; 95% CI, 0.78-1.53), suggesting that survival in black patients depends more strongly on tumor size in this subgroup. Tests for race-size method of detection interactions were statistically significant for overall survival (p = 0.049), locoregional control (p = 0.036), and distant control (p = 0.032) and borderline significant for disease-free survival (p = 0.067).

CONCLUSION

Despite detection at comparable sizes, the prognostic effect of tumor size in patients with mammographically detected tumors is greater for black than in nonblack patients.

Rare BRCA1 haplotypes including 3'UTR SNPs associated with breast cancer risk

Genetic markers identifying women at an increased risk of developing breast cancer exist, yet the majority of inherited risk remains elusive. While numerous BRCA1 coding sequence mutations are associated with breast cancer risk, BRCA1 mutations account for less then 5% of breast cancer risk. Since 3' untranslated region (3'UTR) polymorphisms disrupting microRNA (miRNA) binding can be functional and can act as genetic markers of cancer risk, we tested the hypothesis that such polymorphisms in the 3'UTR of BRCA1 and haplotypes containing these functional polymorphisms may be associated with breast cancer risk. We sequenced the BRCA1 3'UTR from breast cancer patients to identify miRNA disrupting polymorphisms. We further evaluated haplotypes of this region including the identified 3'UTR variants in a large population of controls and breast cancer patients (n = 221) with known breast cancer subtypes and ethnicities. We identified three 3'UTR variants in BRCA1 that are polymorphic in breast cancer populations, and haplotype analysis including these variants revealed that breast cancer patients harbor five rare haplotypes not generally found among controls (9.50% for breast cancer chromosomes, 0.11% for control chromosomes, p = 0.0001). Three of these rare haplotypes contain the rs8176318 BRCA1 3'UTR functional variant. These haplotypes are not biomarkers for BRCA1 coding mutations, as they are found rarely in BRCA1 mutant breast cancer patients (1/129 patients = 0.78%). These rare BRCA1 haplotypes and 3'UTR SNPs may represent new genetic markers of breast cancer risk.

The Clinical Significance of Unknown Sequence Variants in BRCA Genes

Germline mutations in BRCA1/2 genes are responsible for a large proportion of hereditary breast and/or ovarian cancers. Many highly penetrant predisposition alleles have been identified and include frameshift or nonsense mutations that lead to the translation of a truncated protein. Other alleles contain missense mutations, which result in amino acid substitution and intronic variants with splicing effect. The discovery of variants of uncertain/unclassified significance (VUS) is a result that can complicate rather than improve the risk assessment process. VUSs are mainly missense mutations, but also include a number of intronic variants and in-frame deletions and insertions. Over 2,000 unique BRCA1 and BRCA2 missense variants have been identified, located throughout the whole gene (Breast Cancer Information Core Database (BIC database)). Up to 10-20% of the BRCA tests report the identification of a variant of uncertain significance. There are many methods to discriminate deleterious/high-risk from neutral/low-risk unclassified variants (i.e., analysis of the cosegregation in families of the VUS, measure of the influence of the VUSs on the wild-type protein activity, comparison of sequence conservation across multiple species), but only an integrated analysis of these methods can contribute to a real interpretation of the functional and clinical role of the discussed variants. The aim of our manuscript is to review the studies on BRCA VUS in order to clarify their clinical relevance.

Non-founder BRCA1 mutations in Russian breast cancer patients

A few founder BRCA1 mutations (5382insC, 4154delA, 185delAG) account for up to 15% of high-risk (young-onset or familial or bilateral) breast cancer (BC) cases in Russia. The impact of non-founder BRCA1 mutations in this country is less studied; in particular, there are no reports analyzing gross rearrangements of this gene in the Russian patient series. We selected for the study 95 founder mutation negative high-risk BC cases. Combination of high-resolution melting (HRM) and sequencing revealed six presumably BC-associated alleles (2080delA, 4808C>G, 5214C>T, 5236G>A, 5460G>T, 5622C>T) and one variant of an unknown significance (4885G>A). The pathogenic role of the 5236G>A mutation leading to G1706E substitution was further confirmed by the loss of heterozygosity analysis of the corresponding tumor tissue. Multiplex ligation-dependent probe amplification (MLPA) revealed two additional BRCA1 heterozygotes, which carried BRCA1 deletions involving exons 1-2 and 3-7, respectively. Based on the results of this investigation and the review of prior Russian studies, three BRCA1 mutations (2080delA, 3819del5, 3875del4) were considered with respect to their possible founder effect and tested in the additional series of 210 high-risk BC patients; two BRCA heterozygotes (2080delA and 3819del5) were revealed. We conclude that the non-founder mutations constitute the minority of BRCA1 defects in Russia.

Updating and refining a study brochure for a cancer registry-based study of BRCA mutations among young African American breast cancer patients: lessons learned

The aim of the present study was to update, refine, and evaluate a study brochure to promote participation in a population-based study of BRCA mutations among AA women with a personal history of early-onset breast cancer. A multi-step approach was used to develop this brochure and included: (1) feedback from community members (through a Community Advisory Panel (CAP)) to develop and refine the study brochure, (2) pilot testing of materials with the target audience, and (3) review of pilot testing results with the CAP. Based on the feedback received at each step, the study brochure was refined. In phase 1, the major changes included emphasizing the concept of leaving a legacy and family, using the terms Black and women of color, and use of patient vignettes and photos. In phase 2, attraction and cultural acceptability were identified as two areas for improvement in the study brochure. These results demonstrate that involvement of community members and target study population in the development of a study-specific brochure can provide invaluable feedback to optimize recruitment strategies. This approach can be readily adapted to develop study recruitment materials for individuals from a variety of cultural and ethnic backgrounds.

BRCA1 and BRCA2 mutations across race and ethnicity: distribution and clinical implications

PURPOSE OF REVIEW

To summarize evidence on the prevalence and spectrum of BRCA1 and BRCA2 BRCA1/2 mutations across racial and ethnic groups and discuss implications for clinical practice.

RECENT FINDINGS

The prevalence of BRCA1/2 mutations is comparable among breast cancer patients of African, Asian, white, and Hispanic descent: approximately 1-4% per gene. Among ovarian cancer patients in North America, BRCA1/2 mutations are present in 13-15%. Between racial/ethnic groups, there are important differences in the spectrum of BRCA1 compared with BRCA2 mutations, in BRCA1/2 variants of uncertain significance, and in the accuracy of clinical models that predict BRCA1/2 mutation carriage.

SUMMARY

Given the significant prevalence of BRCA1/2 mutations across race/ethnicity, there is a need to expand and customize genetic counseling, genetic testing, and follow-up care for members of all racial/ethnic groups.

Effect of genetic counseling and testing for BRCA1 and BRCA2 mutations in African American women: a randomized trial

BACKGROUND

Limited empirical data are available on the effects of genetic counseling and testing among African American women.

OBJECTIVE

To evaluate the effects of genetic counseling and testing in African American women based on different levels of exposure: (a) women who were randomized to culturally tailored (CTGC) and standard genetic counseling (SGC) to women who declined randomization (non-randomized group), (b) participants and non-participants in genetic counseling, and (c) BRCA1 and BRCA2 (BRCA1/2) test result acceptors and decliners.

DESIGN

Randomized trial of genetic counseling conducted from February 2003 to November 2006.

MEASURES

We evaluated changes in perceived risk of developing breast cancer and cancer worry.

RESULTS

Women randomized to CTGC and SGC did not differ in terms of changes in risk perception and cancer worry compared to decliners. However, counseling participants had a significantly greater likelihood of reporting reductions in perceived risk compared to non-participants (p = 0.03). Test result acceptors also had a significantly greater likelihood of reporting decreases in cancer worry (p = 0.03). However, having a cancer history (p = 0.03) and a BRCA1/2 prior probability (p = 0.04) were associated with increases in cancer worry.

CONCLUSIONS

Although CTGC did not lead to significant improvements in perceived risk or psychological functioning, African American women may benefit from genetic counseling and testing. Continued efforts should be made to increase access to genetic counseling and testing among African American women at increased risk for hereditary disease. But, follow-up support may be needed for women who have a personal history of cancer and those with a greater prior probability of having a BRCA1/2 mutation.

Clinical application of breast cancer risk assessment models

With the evolving availability of testing for genetic cancer syndromes, oncologists now are increasingly expected to review family histories and to give a genetic risk assessment as part of their care for breast cancer. The most important of these breast cancer genetic syndromes identified to date have been those associated with the BRCA1 and BRCA2 genes. Therefore, the proper identification of potentially affected families and providing risk assessment estimates will be ever more essential. This review outlines several different available breast cancer risk assessment models. Risk models for the development of breast cancer as well as risk models that estimate the chance of having a genetic cancer syndrome are discussed. Their clinical applications are also outlined and clinical situations appropriate for each model are reviewed.

Estimating CDKN2A carrier probability and personalizing cancer risk assessments in hereditary melanoma using MelaPRO

Personalized cancer risk assessment remains an essential imperative in postgenomic cancer medicine. In hereditary melanoma, germline CDKN2A mutations have been reproducibly identified in melanoma-prone kindreds worldwide. However, genetic risk counseling for hereditary melanoma remains clinically challenging. To address this challenge, we developed and validated MelaPRO, an algorithm that provides germline CDKN2A mutation probabilities and melanoma risk to individuals from melanoma-prone families. MelaPRO builds on comprehensive genetic information, and uses Mendelian modeling to provide fine resolution and high accuracy. In an independent validation of 195 individuals from 167 families, MelaPRO exhibited good discrimination with a concordance index (C) of 0.86 [95% confidence intervals (95% CI), 0.75-0.97] and good calibration, with no significant difference between observed and predicted carriers (26; 95% CI, 20-35, as compared with 22 observed). In cross-validation, MelaPRO outperformed the existing predictive model MELPREDICT (C, 0.82; 95% CI, 0.61-0.93), with a difference of 0.05 (95% CI, 0.007-0.17). MelaPRO is a clinically accessible tool that can effectively provide personalized risk counseling for all members of hereditary melanoma families.

Influence of race/ethnicity on genetic counseling and testing for hereditary breast and ovarian cancer

Risk assessment coupled with genetic counseling and testing for the cancer predisposition genes BRCA1 and BRCA2 (BRCA1/2) has become an integral element of comprehensive patient evaluation and cancer risk management in the United States for individuals meeting high-risk criteria for hereditary breast and ovarian cancer (HBOC). For mutation carriers, several options for risk modification have achieved substantial reductions in future cancer risk. However, several recent studies have shown lower rates of BRCA1/2 counseling and testing among minority populations. Here, we explore the role of race/ethnicity in cancer risk assessment, genetic counseling and genetic testing for HBOC and the BRCA1/2 cancer predisposition genes. Barriers to genetic services related to race/ethnicity and underserved populations, including socioeconomic barriers (e.g., time, access, geographic, language/cultural, awareness, cost) and psychosocial barriers (e.g., medical mistrust, perceived disadvantages to genetic services), as well as additional barriers to care once mutation carriers are identified, will be reviewed.

The influence of acculturation and breast cancer-specific distress on perceived barriers to genetic testing for breast cancer among women of African descent

OBJECTIVE

Rising health disparities are increasingly evident in relation to use of genetic services (including genetic counseling and testing) for breast cancer risk, with women of African descent less likely to use genetic services compared with Whites. Meanwhile, little is known regarding potential within-group acculturation and psychological differences underlying perceived barriers to genetic testing among women of African descent.

METHODS

Hypothesized contributions of acculturation factors and breast cancer-specific distress to perceived barriers to genetic testing were examined with a statistical analysis of baseline data from 146 women of African descent (56% US born and 44% foreign born) meeting genetic breast cancer risk criteria and participating in a larger longitudinal study that included the opportunity for free genetic counseling and testing. Perceived barriers assessed included: (1) anticipation of negative emotional reactions, (2) stigma, (3) confidentiality concerns, (4) family-related worry, and (5) family-related guilt associated with genetic testing.

RESULTS

In multivariate analyses, being foreign born was a significant predictor of anticipated negative emotional reactions about genetic testing (beta=0.26; SE=0.11; p=0.01). Breast cancer-specific distress scores (avoidance symptoms) were positively related to anticipated negative emotional reactions (beta=0.02; SE=0.005; p=<0.0001), confidentiality concerns (beta=0.02; SE=0.01; p=0.02), and family-related guilt (beta=0.02; SE=0.01; p=0.0009) associated with genetic testing.

CONCLUSIONS

Results suggest an influence of acculturation and breast cancer-specific distress on perceived barriers to genetic testing among women of African descent. The potential utility of culturally tailored genetic counseling services taking into account such influences and addressing emotional and psychological concerns of women considering genetic testing for breast cancer should be investigated.

Utilization of religious coping strategies among African American women at increased risk for hereditary breast and ovarian cancer

This observational study evaluated utilization of religious coping strategies among 95 African American women who were at increased risk for having a BRCA1/BRCA2 (BRCA1/2) mutation. Overall, women reported high levels of collaborative coping; however, women with fewer than 2 affected relatives (beta = -1.97, P = 0.04) and those who had a lower perceived risk of having a BRCA1/2 mutation (beta = -2.72, P = 0.01) reported significantly greater collaborative coping. These results suggest that African American women may be likely to use collaborative strategies to cope with cancer-related stressors. It may be important to discuss utilization of religious coping efforts during genetic counseling with African American women.

Emotional distress following genetic testing for hereditary breast and ovarian cancer: a meta-analytic review

OBJECTIVE

Meta-analysis was used to synthesize results of studies on emotional consequences of predictive genetic testing for BRCA1/2 mutations conferring increased risk of breast and ovarian cancer.

DESIGN

Studies assessing anxiety or cancer-specific distress before and after provision of test results (k = 20) were analyzed using a random-effects model. Moderator variables included country of data collection and personal cancer history of study participants.

MAIN OUTCOME MEASURES

Standardized mean gain effect sizes were calculated for mutation carriers, noncarriers, and those with inconclusive results over short (0-4 weeks), moderate (5-24 weeks), or long (25-52 weeks) periods of time after testing.

RESULTS

Distress among carriers increased shortly after receiving results and returned to pretesting levels over time. Distress among noncarriers and those with inconclusive results decreased over time. Some distress patterns differed in studies conducted outside the United States and for individuals with varying cancer histories.

CONCLUSION

Results underscore the importance of time; changes in distress observed shortly after test-result disclosure frequently differed from the pattern of distress seen subsequently. Although emotional consequences of this testing appear minimal, it remains possible that testing may affect cognitive and behavioral outcomes, which have rarely been examined through meta-analysis. Testing may also affect understudied subgroups differently.

Breast cancer in young women (YBC): prevalence of BRCA1/2 mutations and risk of secondary malignancies across diverse racial groups

BACKGROUND

Despite significant differences in age of onset and incidence of breast cancer between Caucasian (CA), African-American (AA) and Korean (KO) women, little is known about differences in BRCA1/2 mutations in these populations. The purpose of this study is to evaluate the prevalence of BRCA1/2 mutations and the association between BRCA1/2 mutation status and secondary malignancies among young women with breast cancer in these three racially diverse groups.

METHODS

Patients presenting to our breast cancer follow-up clinics selected solely on having a known breast cancer diagnosis at a young age (YBC defined as age <45 years at diagnosis) were invited to participate in this study. A total of 333 eligible women, 166 CA, 66 AA and 101 KO underwent complete sequencing of BRCA1/2 genes. Family history (FH) was classified as negative, moderate or strong. BRCA1/2 status was classified as wild type (WT), variant of uncertain significance (VUS) or deleterious (DEL).

RESULTS

DEL across these three racially diverse populations of YBC were nearly identical: CA 17%, AA 14% and KO 14%. The type of DEL differed with AA having more frequent mutations in BRCA2, compared with CA and KO. VUS were predominantly in BRCA2 and AA had markedly higher frequency of VUS (38%) compared with CA (10%) and KO (12%). At 10-year follow-up from the time of initial diagnosis of breast cancer, the risk of secondary malignancies was similar among WT (14%) and VUS (16%), but markedly higher among DEL (39%).

CONCLUSIONS

In these YBC, the frequency of DEL in BRCA1/2 is remarkably similar among the racially diverse groups at 14%-17%. VUS is more common in AA, but aligns closely with WT in risk of second cancers, age of onset and FH.

BRCA1 and BRCA2 mutations in women of different ethnicities undergoing testing for hereditary breast-ovarian cancer

BACKGROUND

In women at increased risk for breast and ovarian cancer, the identification of a mutation in breast cancer gene 1 (BRCA1) and BRCA2 has important implications for screening and prevention counseling. Uncertainty regarding the role of BRCA1 and BRCA2 testing in high-risk women from diverse ancestral backgrounds exists because of variability in prevalence estimates of deleterious (disease-associated) mutations in non-white populations. In this study, the authors examined the prevalence of BRCA1 and BRCA2 mutations in an ethnically diverse group of women who were referred for genetic testing.

METHODS

In this cross-sectional analysis, the prevalence of BRCA1 and BRCA2 mutations was assessed in a group of non-Ashkenazi Jewish women who underwent genetic testing.

RESULTS

From 1996 to 2006, 46,276 women who met study criteria underwent DNA full-sequence analysis of the BRCA1 and BRCA2 genes. Deleterious mutations were identified in 12.5% of women, and recurrent deleterious mutations (prevalence >2%) were identified in all ancestral groups. Women of non-European descent were younger (mean age, 45.9 years; standard deviation [SD], 11.6 years) than European women (mean age, 50 years; SD, 11.9 years; P < .001). Women of African (15.6%; odds ratio [OR], 1.3 [95% confidence interval (95% CI), 1.1-1.5]) and Latin American (14.8%; OR, 1.2 [95% CI, 1.1-1.4]) ancestries had a significantly higher prevalence of deleterious BRCA1 and BRCA2 mutations compared with women of Western European ancestry (12.1%), primarily because of an increased prevalence of BRCA1 mutations in those 2 groups. Non-European ethnicity was associated strongly with having a variant of uncertain significance; however, reclassification decreased variant reporting (from 12.8%-->5.9%), and women of African ancestry experienced the largest decline (58%).

CONCLUSIONS

Mutation prevalence was found to be high among women who were referred for clinical BRCA1 and BRCA2 testing, and the risk was similar across diverse ethnicities. BRCA1 and BRCA2 testing is integral to cancer risk assessment in all high-risk women.

Performance of prediction models for BRCA mutation carriage in three racial/ethnic groups: findings from the Northern California Breast Cancer Family Registry

PURPOSE

Patients with early-onset breast and/or ovarian cancer frequently wish to know if they inherited a mutation in one of the cancer susceptibility genes, BRCA1 or BRCA2. Accurate carrier prediction models are needed to target costly testing. Two widely used models, BRCAPRO and BOADICEA, were developed using data from non-Hispanic Whites (NHW), but their accuracies have not been evaluated in other racial/ethnic populations.

METHODS

We evaluated the BRCAPRO and BOADICEA models in a population-based series of African American, Hispanic, and NHW breast cancer patients tested for BRCA1 and BRCA2 mutations. We assessed model calibration by evaluating observed versus predicted mutations and attribute diagrams, and model discrimination using areas under the receiver operating characteristic curves.

RESULTS

Both models were well-calibrated within each racial/ethnic group, with some exceptions. BOADICEA overpredicted mutations in African Americans and older NHWs, and BRCAPRO underpredicted in Hispanics. In all racial/ethnic groups, the models overpredicted in cases whose personal and family histories indicated >80% probability of carriage. The two models showed similar discrimination in each racial/ethnic group, discriminating least well in Hispanics. For example, BRCAPRO's areas under the receiver operating characteristic curves were 83% (95% confidence interval, 63-93%) for NHWs, compared with 74% (59-85%) for African Americans and 58% (45-70%) for Hispanics.

CONCLUSIONS

The poor performance of the model for Hispanics may be due to model misspecification in this racial/ethnic group. However, it may also reflect racial/ethnic differences in the distributions of personal and family histories among breast cancer cases in the Northern California population.