Variants of unknown significance in BRCA testing: impact on risk perception, worry, prevention and counseling

Implications of genetic testing and informed consent before and after genetic testing in individuals with cancer

Recent advancements in next generation sequencing have allowed for genetic information become more readily available in the clinical setting for those affected by cancer and by treating clinicians. Given the lack of access to geneticists, medical oncologists and other treating physicians have begun ordering and interpreting genetic tests for individuals with cancer through the process of "mainstreaming". While this process has allowed for quicker access to genetic tests, the process of "mainstreaming" has also brought several challenges including the dissemination of variants of unknown significance results, ordering of appropriate tests, and accurate interpretation of genetic results with appropriate follow-up testing and interventions. In this editorial, we seek to explore the process of informed consent of individuals before obtaining genetic testing and offer potential solutions to optimize the informed consent process including categorization of results as well as a layered consent model.

Clinical implications of VUS reclassification in a single-centre series from application of ACMG/AMP classification rules specified for BRCA1/2

BACKGROUND

BRCA1/2 testing is crucial to guide clinical decisions in patients with hereditary breast/ovarian cancer, but detection of variants of uncertain significance (VUSs) prevents proper management of carriers. The ENIGMA (Evidence-based Network for the Interpretation of Germline Mutant Alleles) BRCA1/2 Variant Curation Expert Panel (VCEP) has recently developed BRCA1/2 variant classification guidelines consistent with ClinGen processes, specified against the ACMG/AMP (American College of Medical Genetics and Genomics/Association for Molecular-Pathology) classification framework.

METHODS

The ClinGen-approved BRCA1/2-specified ACMG/AMP classification guidelines were applied to BRCA1/2 VUSs identified from 2011 to 2022 in a series of patients, retrieving information from the VCEP documentation, public databases, literature and ENIGMA unpublished data. Then, we critically re-evaluated carrier families based on new results and checked consistency of updated classification with main sources for clinical interpretation of BRCA1/2 variants.

RESULTS

Among 166 VUSs detected in 231 index cases, 135 (81.3%) found in 197 index cases were classified by applying BRCA1/2-specified ACMG/AMP criteria: 128 (94.8%) as Benign/Likely Benign and 7 (5.2%) as Pathogenic/Likely Pathogenic. The average time from the first report as 'VUS' to classification using this approach was 49.4 months. Considering that 15 of these variants found in 64 families had already been internally reclassified prior to this work, this study provided 121 new reclassifications among the 151 (80.1%) remaining VUSs, relevant to 133/167 (79.6%) families.

CONCLUSIONS

These results demonstrated the effectiveness of new BRCA1/2 ACMG/AMP classification guidelines for VUS classification within a clinical cohort, and their important clinical impact. Furthermore, they suggested a cadence of no more than 3 years for regular review of VUSs, which however requires time, expertise and resources.

Electronic medical record documentation of germline genetic evaluations in patients with ovarian cancer

Germline genetic evaluation is indicated for all patients with epithelial ovarian cancer (EOC). For testing to have clinical utility, results must be documented within the electronic medical record (EMR) and accessible to providers at the point of care, which can be challenging in the context of current EMR limitations and genetic testing processes. We examined the receipt of genetics services and EMR capture of genetic testing results in patients with EOC. We conducted a retrospective chart review to examine germline genetic evaluations among patients with EOC seen by a gynecologic or medical oncologist at the University of Pennsylvania in 2016. EMRs were reviewed to determine: (1) if patients were referred for genetic evaluation; (2) if genetic testing was performed; (3) if results were documented in office notes, scanned third-party test reports, and/or the EMR problem list; (4) if provider notes correctly listed the variant classification. Overall, 413 (62%) of patients had documented genetic testing. Genetic testing was documented in almost all provider notes (96%) and the majority of scanned EMR reports (64%). Pathogenic variants were found in 119 (29%) individuals; the majority (70%) had genetic testing documented within EMR problem lists. Provider notes were highly accurate in describing variant classification. In this study, genetic testing was performed and documented in the EMR for most EOC patients. Approximately one-third of those tested did not have scanned test reports specifying variant found, limiting the utility of test results for cascade testing and therapeutic decisions.

Genomic disparity impacts variant classification of cancer susceptibility genes in Turkish breast cancer patients

OBJECTIVE

Turkish genome is underrepresented in large genomic databases. This study aims to evaluate the effect of allele frequency in the Turkish population in determining the clinical utility of germline findings in breast cancer, including invasive lobular carcinoma (ILC), mixed invasive ductal and lobular carcinoma (IDC-L), and ductal carcinoma (DC).

METHODS

Two clinic-based cohorts from the Umraniye Research and Training Hospital (URTH) were used in this study: a cohort consisting of 132 women with breast cancer and a non-cancer cohort consisting of 492 participants. The evaluation of the germline landscape was performed by analysis of 27 cancer genes. The frequency and type of variants in the breast cancer cohort were compared to those in the non-cancer cohort to investigate the effect of population genetics. The variant allele frequencies in Turkish Variome and gnomAD were statistically evaluated.

RESULTS

The genetic analysis identified 121 variants in the breast cancer cohort (actionable = 32, VUS = 89) and 223 variants in the non-cancer cohort (actionable = 25, VUS = 188). The occurrence of 21 variants in both suggested a possible genetic population effect. Evaluation of allele frequency of 121 variants from the breast cancer cohort showed 22% had a significantly higher value in Turkish Variome compared to gnomAD (p < 0.0001, 95% CI) with a mean difference of 60 times (ranging from 1.37-354.4). After adjusting for variant allele frequency using the ancestry-appropriate database, 6.7% (5/75) of VUS was reclassified to likely benign.

CONCLUSION

To our knowledge, this is the first study of population genetic effects in breast cancer subtypes in Turkish women. Our findings underscore the need for a large genomic database representing Turkish population-specific variants. It further highlights the significance of the ancestry-appropriate population database for accurate variant assessment in clinical settings.

Clinical outcomes and response to chemotherapy in a cohort of pancreatic cancer patients with germline variants of unknown significance (VUS) in BRCA1 and BRCA2 genes

PURPOSE

The clinical outcome and the efficacy of chemotherapy in pancreatic cancer patients with BRCA1/2 Variants of Unknown Significance (VUS) is unknown. We explored the effects of chemotherapy with or without Platinum in non metastatic and metastatic pancreatic cancer patients with BRCA1/2 VUS.

METHODS

A retrospective analysis of non-metastatic or metastatic pancreatic cancer patients with gBRCA1/2 VUS treated in 13 Italian centers between November 2015 and December 2020 was performed. All patients were assessed for toxicity and RECIST 1.1 response. Metastatic patients were evaluated for survival outcome.

RESULTS

30 pancreatic cancer patients with gBRCA1/2 VUS were considered: 20 were M+ and 10 were non-M+. Pl-CT was recommended to 16 patients: 10 M+ (6 FOLFIRINOX and 4 PAXG) and 6 non-M+ (3 FOLFIRINOX and 3 PAXG); 11 patients received Nabpaclitaxel-Gemcitabine (AG; 8 M+) and 3 patients (2 M+) were treated with Gemcitabine (G). The RECIST 1.1 response rate was 27% for AG and 44% for Pl-CT (22% for (m) FOLFIRINOX and 71% PAXG). 1 year Progression-Free Survival was 37.5% for patients treated with AG and 33% in the Pl-CT subgroup. Median Overall Survival (OS) was 23.5 months for patients treated with AG and 14 months for the Pl-CT subgroup. 1 Year and 2 Year OS were numerically better for AG (1 Year OS: 75% vs 60% and 2 Year OS: 50% and 20% in AG and Pl-CT subgroups, respectively) as well.

CONCLUSIONS

Pl-CT does not seem to be associated with a better outcome compared to AG chemotherapy in PDAC patients with BRCA 1/2 VUS.

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.

Ovarian cancer pathology characteristics as predictors of variant pathogenicity in BRCA1 and BRCA2

BACKGROUND

The distribution of ovarian tumour characteristics differs between germline BRCA1 and BRCA2 pathogenic variant carriers and non-carriers. In this study, we assessed the utility of ovarian tumour characteristics as predictors of BRCA1 and BRCA2 variant pathogenicity, for application using the American College of Medical Genetics and the Association for Molecular Pathology (ACMG/AMP) variant classification system.

METHODS

Data for 10,373 ovarian cancer cases, including carriers and non-carriers of BRCA1 or BRCA2 pathogenic variants, were collected from unpublished international cohorts and consortia and published studies. Likelihood ratios (LR) were calculated for the association of ovarian cancer histology and other characteristics, with BRCA1 and BRCA2 variant pathogenicity. Estimates were aligned to ACMG/AMP code strengths (supporting, moderate, strong).

RESULTS

No histological subtype provided informative ACMG/AMP evidence in favour of BRCA1 and BRCA2 variant pathogenicity. Evidence against variant pathogenicity was estimated for the mucinous and clear cell histologies (supporting) and borderline cases (moderate). Refined associations are provided according to tumour grade, invasion and age at diagnosis.

CONCLUSIONS

We provide detailed estimates for predicting BRCA1 and BRCA2 variant pathogenicity based on ovarian tumour characteristics. This evidence can be combined with other variant information under the ACMG/AMP classification system, to improve classification and carrier clinical management.

Paving a pathway for large-scale utilization of genomics in precision medicine and population health

Having worked with two large population sequencing initiatives, the separation between the potential for genomics in precision medicine and the current reality have become clear. To realize this potential requires workflows, policies, and technical architectures that are foreign to most healthcare systems. Many historical processes and regulatory barriers currently impede our progress. The future of precision medicine includes genomic data being widely available at the point of care with systems in place to manage its efficient utilization. To achieve such vision requires substantial changes in billing, reimbursement, and reporting as well as the development of new systemic and technical architectures within the healthcare system. Clinical geneticist roles will evolve into managing precision health frameworks and genetic counselors will serve crucial roles in both leading and supporting precision medicine through the implementation and maintenance of precision medicine architectures. Our current path has many obstacles that hold us back, leaving preventable deaths in the wake. Reengineering our healthcare systems to support genomics can have a major impact on patient outcomes and allow us to realize the long-sought promises of precision medicine.

Clinical and laboratory genetic counselor attitudes on the reporting of variants of uncertain significance for multigene cancer panels

Research suggests variants of uncertain significance (VUSs) present a variety of challenges for genetic counselors (GCs), nongenetics clinicians, and patients. Multigene cancer panels reveal more VUSs than single gene testing as a result of the increase in the number of genes being tested. This study surveyed 87 clinical cancer GCs involved with direct patient care and 19 laboratory GCs who provide guidance to clinicians regarding genetic test results about their attitudes on various options for the reporting of VUSs by laboratories for broad multigene cancer panels. Independent samples t-tests were utilized to compare the two groups. Based on a six-point Likert-type scale (1 = Strongly Disagree to 6 = Strongly Agree), clinical cancer GCs (M = 5.4; SD = 0.8) and laboratory GCs (M = 5.2; SD = 0.9) agreed overall that VUSs should be reported (p = 0.44; Cohen's d = 0.21). When asked about specific reporting options, both clinical cancer GCs (M = 1.9; SD = 1.1) and laboratory GCs (M = 2.1; SD = 1.4) disagreed that VUSs should be reported only for genes related to the indication for testing (p = 0.50; Cohen's d = 0.17). Overall, most GCs felt clinicians should not choose whether VUSs should be reported on genetic test results, with clinical cancer GCs (M = 1.9; SD = 1.3) feeling more strongly against it than laboratory GCs (M = 3.1; SD = 1.4; p = 0.002; Cohen's d = 0.88). Generally, GCs were more in favor of VUSs not being reported for population-based screening, with laboratory GCs (M = 4.7; SD = 0.8) agreeing more with that practice than clinical cancer GCs (M = 3.7; SD = 1.4; p = 0.001; Cohen's d = 0.80). Both clinical cancer GCs (M = 4.1; SD = 1.2) and laboratory GCs (M = 3.9; SD = 1.2) agreed additional guidelines on how to approach VUSs in clinical practice should be developed (p = 0.54; Cohen's d = 0.17). While most GCs supported the reporting of VUSs overall, our analyses suggest clinical cancer and laboratory GCs may have different attitudes toward specific VUS-related reporting options. Further research is needed to elucidate GC preferences to help inform best practices for the reporting of VUSs. The development of additional standardized guidelines on how to approach VUSs would further support clinical practice.

Identification of individuals at high-risk for pancreatic cancer using a digital patient-input tool combining family cancer history screening and new-onset diabetes

Capturing family history might be a valuable tool for identification of individuals at increased risk of pancreatic cancer, which would allow enrollment into pancreatic surveillance programs. In addition, weight loss and concurrent new-onset diabetes may be utilized as an early marker for pancreatic cancer. This study evaluates the yield of combining family history and the Enriching New-Onset Diabetes for Pancreatic Cancer (ENDPAC) model to identify individuals who could benefit from pancreatic surveillance. A novel questionnaire and digital input tool was created that combined questions on family cancer history and criteria of the ENDPAC model. Individuals meeting ENDPAC criteria were enrolled directly in the high-risk pancreatic clinic. Individuals who met the criteria for a significant family history of cancer were offered referral to a genetic counselor. The questionnaire was completed by 453 patients. Of those, 25.8% (117/453) had significant familial risk factors. Eighteen individuals (15.4%) completed genetic testing previously, of whom five had a pathogenic variant. Thirty-four (29.9%) out of 117 individuals with a strong family history - flagged by the questionnaire - underwent genetic testing. Four (11.8%) of these patients harbored a pathogenic variant. Additionally, through cascade family testing, two siblings were found to carry pathogenic variants. Four (0.9%) of the 453 patients matched ENDPAC criteria. Two were diagnosed with pancreatic cancer and the others were enrolled in the surveillance program. In conclusion, identification of high-risk individuals for pancreatic cancer can be achieved by combining family history screening and the ENDPAC model to facilitate referral to genetic counseling and high-risk clinics.

Occurrence of variants of unknown clinical significance in genetic testing for hereditary breast and ovarian cancer syndrome and Lynch syndrome: a literature review and analytical observational retrospective cohort study

BACKGROUND AND PURPOSE

Over the last decade, the implementation of multigene panels for hereditary tumor syndrome has increased at our institution (Inselspital, University Hospital Berne, Switzerland). The aim of this study was to determine the prevalence of variants of unknown significance (VUS) in patients with suspected Lynch syndrome and suspected hereditary breast and ovarian cancer syndrome, the latter in connection with the trend toward ordering larger gene panels.

RESULTS

Retrospectively collected data from 1057 patients at our institution showed at least one VUS in 126 different cases (11.9%). In patients undergoing genetic testing for BRCA1/2, the prevalence of VUS was 6%. When < 10 additional genes were tested in addition to BRCA1/2, the prevalence increased to 13.8%, and 31.8% for > 10 additional genes, respectively. The gene most frequently affected with a VUS was ATM. 6% of our patients who were tested for Lynch syndrome had a VUS result in either MLH1, MSH2 or MSH6.

CONCLUSIONS

Our data demonstrate that panel testing statistically significantly increases VUS rates due to variants in non-BRCA genes. Good genetic counseling before and after obtaining results is therefore particularly important when conducting multigene panels to minimize patient uncertainty due to VUS results.

General practitioners' (GPs) experience, attitudes and needs on clinical genetic services: a systematic review

OBJECTIVE

The proliferation and growing demands of genetic testing are anticipated to revolutionise medical practice. As gatekeepers of healthcare systems, general practitioners (GPs) are expected to play a critical role in the provision of clinical genetic services. This paper aims to review existing literature on GPs' experience, attitudes and needs towards clinical genetic services.

DESIGN

A systematic mixed studies review of papers published between 2010 and 2022.

ELIGIBILITY CRITERIA

The inclusion criterion was peer-reviewed articles in English and related to GPs' experience, views and needs on any genetic testing.

INFORMATION SOURCES

The PubMed, PsycINFO, Cochrane, EMBASE databases were searched using Mesh terms, Boolean and wildcards combinations to identify peer-reviewed articles published from 2010 to 2022. Study quality was assessed using Mixed Methods Appraisal Tool. Only articles that fulfilled the inclusion criteria were selected. A thematic meta-synthesis was conducted on the final sample of selected articles to identify key themes.

RESULTS

A total of 62 articles were included in the review. Uncertainty over GPs' role in providing genetic services were attributed by the lack of confidence and time constraints and rarity of cases may further exacerbate their reluctance to shoulder an expanded role in clinical genetics. Although educational interventions were found to increasing GPs' knowledge and confidence to carry out genetic tasks, varied interest on genetic testing and preference for a shared care model with other genetic health professionals have resulted in minimal translation to clinical adoption.

CONCLUSION

This review highlights the need for deeper exploration of GPs' varied experience and attitudes towards clinical genetic services to better facilitate targeted intervention in the adoption of clinical genetics.

Physicians' experience, practice and education, on genetic testing and genetic counseling: a nationwide survey study in Greece

Genetic testing has been implemented in clinical practice. However, data on physician's practices and education related to cancer genetics, risk assessment and clinical management in Greece, is limited. In Greece, genetic counseling is performed by treating physicians in collaboration with clinical laboratory geneticists due to the absence of medical geneticists and genetic counsellors. We evaluated treating physicians' experience on genetic testing for hereditary cancer and counseling practices in Greece, thus providing critical areas for improvement of genetic counseling processes. A 28-question survey was used to assess physicians' experience with genetic testing practices, factors that affect their clinical management and decision making and limitations in their education. Of 250 physicians, 208 (83%) completed the survey; of whom 89 (42.8%) were medical oncologists, 88 general surgeons (42.3%), 26 gynecologists (12.5%) and 5 (2.4%) of other specialties. Overall, 91.8% of participants referred patients for genetic testing, with 51.8% recommending multigene panel testing. While most clinicians (84%) reported lack of a clinical genetics department at their institution, 75.7% referred patients for genetic counseling at available departments or healthcare professionals with expertise in genetic counseling. Overall, 68.8% of respondents reported no training or moderate training on cancer genetics. A higher proportion of medical oncologists reported sufficient/very satisfactory training (40.9%) compared to general surgeons (27.3%) or gynecologists (11.5%) (p = 0.012). Time spent on pre- and post-testing sessions varied significantly among respondents. Of 199 physicians, 70% would manage patients with BRCA1 VUS as patients with pathogenic variants, mainly surgeons (83.1%) and gynecologists (80%), compared to oncologists (52.3%) (p < 0.001). Additionally, 64% of physicians treating patients with breast and ovarian cancer would recommend an intervention based on the presence of a BRCA1 VUS. Most respondents (87%) were interested in receiving additional education on cancer risk assessment. Limited consensus was observed during physicians' genetic testing, counseling practices and clinical management of patients with increased predisposition to cancer. Our findings highlight the need for improvement in physician education on cancer risk assessment and increase of genetic counseling resources and services.

Implication and Influence of Multigene Panel Testing with Genetic Counseling in Korean Patients with BRCA1/2 Mutation-Negative Breast Cancer

PURPOSE

The aim of the study was to evaluate the clinical implication of multigene panel testing of beyond BRCA genes in Korean patients with BRCA1/2 mutation-negative breast cancer.

MATERIALS AND METHODS

Between 2016 and 2019, a total of 700 BRCA1/2 mutation-negative breast cancer patients received comprehensive multigene panel testing and genetic counseling. Among them, 347 patients completed a questionnaire about cancer worry, genetic knowledge, and preference for the method of genetic tests during pre- and post-genetic test counseling. The frequency of pathogenic and likely pathogenic variants (PV/LPV) were analyzed.

RESULTS

At least one PV/LPV of 26 genes was found in 76 out of 700 patients (10.9 %). The rate for PV/LPV was 3.4% for high-risk genes (17 PALB2, 6 TP53, and 1 PTEN). PV/LPVs of clinical actionable genes for breast cancer management, high-risk genes and other moderate-risk genes such as ATM, BARD1, BRIP, CHEK2, NF1, and RAD51D, were observed in 7.4%. Patients who completed the questionnaire showed decreased concerns about the risk of additional cancer development (average score, 4.21 to 3.94; p < 0.001), influence on mood (3.27 to 3.13; p < 0.001), influence on daily functioning (3.03 to 2.94; p=0.006); and increased knowledge about hereditary cancer syndrome (66.9 to 68.8; p=0.025) in post-test genetic counseling. High cancer worry scales (CWSs) were associated with age ≤ 40 years and the identification of PV/LPV. Low CWSs were related to the satisfaction of the counselee.

CONCLUSION

Comprehensive multigene panel test with genetic counseling is clinically applicable. It should be based on interpretable genetic information, consideration of potential psychological consequences, and proper preventive strategies.

An integrated somatic and germline approach to aid interpretation of germline variants of uncertain significance in cancer susceptibility genes

Genomic profiles of tumors are often unique and represent characteristic mutational signatures defined by DNA damage or DNA repair response processes. The tumor-derived somatic information has been widely used in therapeutic applications, but it is grossly underutilized in the assessment of germline genetic variants. Here, we present a comprehensive approach for evaluating the pathogenicity of germline variants in cancer using an integrated interpretation of somatic and germline genomic data. We have previously demonstrated the utility of this integrated approach in the reassessment of pathogenic germline variants in selected cancer patients with unexpected or non-syndromic phenotypes. The application of this approach is presented in the assessment of rare variants of uncertain significance (VUS) in Lynch-related colon cancer, hereditary paraganglioma-pheochromocytoma syndrome, and Li-Fraumeni syndrome. Using this integrated method, germline VUS in PMS2, MSH6, SDHC, SHDA, and TP53 were assessed in 16 cancer patients after genetic evaluation. Comprehensive clinical criteria, somatic signature profiles, and tumor immunohistochemistry were used to re-classify VUS by upgrading or downgrading the variants to likely or unlikely actionable categories, respectively. Going forward, collation of such germline variants and creation of cross-institutional knowledgebase datasets that include integrated somatic and germline data will be crucial for the assessment of these variants in a larger cancer cohort.

Diagnostic yield and clinical relevance of expanded genetic testing for cancer patients

BACKGROUND

Genetic testing (GT) for hereditary cancer predisposition is traditionally performed on selected genes based on established guidelines for each cancer type. Recently, expanded GT (eGT) using large hereditary cancer gene panels uncovered hereditary predisposition in a greater proportion of patients than previously anticipated. We sought to define the diagnostic yield of eGT and its clinical relevance in a broad cancer patient population over a 5-year period.

METHODS

A total of 17,523 cancer patients with a broad range of solid tumors, who received eGT at Memorial Sloan Kettering Cancer Center between July 2015 to April 2020, were included in the study. The patients were unselected for current GT criteria such as cancer type, age of onset, and/or family history of disease. The diagnostic yield of eGT was determined for each cancer type. For 9187 patients with five common cancer types frequently interrogated for hereditary predisposition (breast, colorectal, ovarian, pancreatic, and prostate cancer), the rate of pathogenic/likely pathogenic (P/LP) variants in genes that have been associated with each cancer type was analyzed. The clinical implications of additional findings in genes not known to be associated with a patients' cancer type were investigated.

RESULTS

16.7% of patients in a broad cancer cohort had P/LP variants in hereditary cancer predisposition genes identified by eGT. The diagnostic yield of eGT in patients with breast, colorectal, ovarian, pancreatic, and prostate cancer was 17.5%, 15.3%, 24.2%, 19.4%, and 15.9%, respectively. Additionally, 8% of the patients with five common cancers had P/LP variants in genes not known to be associated with the patient's current cancer type, with 0.8% of them having such a variant that confers a high risk for another cancer type. Analysis of clinical and family histories revealed that 74% of patients with variants in genes not associated with their current cancer type but which conferred a high risk for another cancer did not meet the current GT criteria for the genes harboring these variants. One or more variants of uncertain significance were identified in 57% of the patients.

CONCLUSIONS

Compared to targeted testing approaches, eGT can increase the yield of detection of hereditary cancer predisposition in patients with a range of tumors, allowing opportunities for enhanced surveillance and intervention. The benefits of performing eGT should be weighed against the added number of VUSs identified with this approach.

Multi-Gene Mutation Profiling by Targeted Next-Generation Sequencing in Premenopausal Breast Cancer

Breast cancer has distinct etiology, prognoses, and clinical outcomes at premenopausal ages. Determination of the frequency of germline and somatic mutations will refine our understanding of the genetic contribution to premenopausal breast cancer susceptibility. We applied a comprehensive next generation sequencing-based approach to analyze blood and/or tissue samples of 54 premenopausal breast cancer patients treated in our clinic. Genetic testing results were descriptively analyzed in correlation with clinicopathological data. In the present study, 42.5% of premenopausal breast cancer patients tested carried pathogenic mutations in cancer predisposition genes (CHEK2, BRCA1, TP53, and MUTYH). Germline variants of unknown/uncertain significance (VUSs) in eight different cancer susceptibility genes, namely BRCA1, BRCA2, CHEK2, RAD51C, RAD51D, ATM, BRIP1, and PMS2, were also identified in 14 premenopausal patients (35%). Of the breast tumors tested, 61.8% harbored pathogenic somatic variants in tumor suppressor genes (TP53, NF1, RB), genes involved in DNA repair (BRCA1, BRCA2, ATM, RAD50), cell proliferation (PTEN, PIK3C FGFR3, AKT1, ROS1, ERBB2, NOTCH1), and cell adhesion (CTNNB1). This descriptive study employs the powerful NGS technology to highlight the high frequency of premenopausal cases attributable to genetic predisposition. Mutation identification in a larger cohort may further ensure that these patients receive tailored treatment according to their menopausal status.

Experiences of individuals with a variant of uncertain significance on genetic testing for hereditary cancer risks: a mixed method systematic review

The expansion of Multi-Gene Panel Testing (MGPT) has led to increased detection of variants of uncertain significance (VUS) among individuals with personal or family history of cancer. However, having a VUS result can impact on emotional and psychological wellbeing and cause challenges for non-geneticist healthcare providers. The purpose of this mixed methods systematic review was to examine what is currently known about the experiences of individuals with a VUS on genetic testing for inherited cancer susceptibility. The initial search was conducted in June 2020 using PUBMED, CINAHL, Web of Science, and PsychInfo according to the Joanna Briggs methodology for systematic reviews. A total of 18 studies met the inclusion criteria. Studies included in this review identified a range of emotional reactions to a VUS result, a general lack of understanding of a VUS result and its implications, frustration with a lack of healthcare provider knowledge, and a need for clear communication with healthcare providers. This review identified critical gaps in current knowledge to guide genetic counseling praxis, specifically in the knowledge of communication patterns and methods of improving communication with healthcare providers and family members and preferred risk management strategies. This will help to improve the counseling process and the management of care during and after genetic testing.

BRCA1, BRCA2, TP53, PIK3CA, PTEN and AKT1 genes mutations in Burkina Faso breast cancer patients: prevalence, spectrum and novel variant

BRCA1 and BRCA2 are the two most commonly mutated tumor suppressor genes associated with hereditary breast cancer (BC). Also, mutations in TP53, PIK3CA, PTEN and AKT1 were observed at a high frequency in BC with their mutation spectrum exhibiting a subgroup particularity with enormous clinical significance in the prevention, classification and treatment of cancers. Unfortunately, the mutation spectrum of these genes is still unknown in most Sub-Saharan African population. Therefore, using samples from 133 unselected BC patients, we aimed to assess the contribution of these mutations by direct Sanger sequencing. The analysis revealed pathogenic germline variants on BRCA1 exon 11 (c.3331C > T, 0.75%) and BRCA2 exon 11 (c.5635G > T, c.6211delA; 1.5%). Five other pathogenic variants were identified in 61 of the 133 subjects (45.86%), with 39.09% for PIK3CA, 12.78% for TP53. Interestingly, a variant in PIK3CA found in high frequency in our population was different from the one usually found in other populations (c.1634A > C, 38.34%), and four patients carried mutations linked to Cowen Syndrome 5 c.[1634A > C;1658_1659delGTinsC]. A novel variant (c.312G > T) was found in TP53 gene at 12.78%. Overall, mutation carriers were found more in Her2 negative and in patients that underwent surgery and chemotherapy. No pathogenic variant was found in PTEN and AKT1. Our population displayed a high frequency of PIK3CA mutations with an unusual distribution and spectrum as well as a relatively low prevalence of BRCA mutations. Our results provided novel data on an unstudied population and may help in prevention, and the establishment of suitable therapeutic approaches for our population.

Challenges and potential solutions to health disparities in genomic medicine

Significant disparities in the clinical usefulness of genomic information across diverse groups are due to underrepresentation in genetic databases and inequitable access to genetic services. Remedying disparities is immediately needed to ensure that genomic medicine is more equitable but will take a long-term commitment and active engagement of diverse communities.

Is there a way to reduce the inequity in variant interpretation on the basis of ancestry?

The underrepresentation of non-European ancestry groups in current genomic databases complicates interpretation of their genetic test results, yielding a much higher prevalence of variants of uncertain significance (VUSs). Such VUS findings can frustrate the goals of genetic testing, create anxiety in patients, and lead to unnecessary medical interventions. Approaches to addressing underrepresentation of people with genetic ancestries other than European are being undertaken by broad-based recruitment efforts. However, some underrepresented groups have concerns that might preclude participation in such efforts. We describe here two initiatives aimed at meeting the needs of underrepresented ancestry groups in genomic datasets. The two communities, the Sephardi Jewish community in New York and First Peoples of Canada, have very different concerns about contributing to genomic research and datasets. Sephardi concerns focus on the possible negative effects of genetic findings on the marriage prospects of family members. Canadian Indigenous populations seek control over the research uses to which their genetic data would be put. Both cases involve targeted efforts to respond to the groups' concerns; these efforts include governance models aimed at ensuring that the data are used primarily to inform clinical test analyses and at achieving successful engagement and participation of community members. We suggest that these initiatives could provide models for other ancestral groups seeking to improve the accuracy and utility of clinical genetic testing while respecting the underlying preferences and values of community members with regard to the use of their genetic data.

Rates of Variants of Uncertain Significance Among Patients With Breast Cancer Undergoing Genetic Testing: Regional Perspectives

Purpose

Contrary to BRCA pathogenic variants, recommendations for management of variants of uncertain significance (VUS) are not clear and focus more on the patient’s family and personal history of cancer. Local and regional data on VUS are scarce. In this paper, we study patterns and frequency of VUS among breast cancer patients undergoing genetic testing.

Patients and Methods

Patients with breast cancer at high risk for pathogenic variants, as per the National Comprehensive Cancer Network (NCCN) guidelines, were tested at reference laboratories. Related surgical interventions were reviewed.

Results

Among a group of 1,197 patients with breast cancer who underwent genetic testing and counseling, 110 (9.2%) had VUS; most (n = 79, 71.8%) were in BRCA2. Median age (range) was 39 (25–66) years with 65 (59.1%) patients who were 40 years or younger at diagnosis. Among 103 patients with non-metastatic disease, 48 (46.6%) had breast-conserving surgery (BCS) while only 5 (4.9%) had bilateral mastectomies; all were due to bilateral disease and not prophylactic. VUS diagnosis was known prior to initial surgery in 34 (33.0%) patients; 11 (32.4%) of them had BCS only. Over the study period, only one VUS variant was upgraded to “likely positive.” The recent introduction of multiple-gene panel testing had resulted in a surge in VUS rate (22.2%) in genes other than BRCA1 or BRCA2, like PALB2, CHEK2, and ATM.

Conclusions

Rates of VUS are relatively high and increasing, mostly in non-BRCA1 or BRCA2, and this had no impact on the therapeutic or prophylactic surgical decisions. Adherence to guidelines is extremely important to avoid unnecessary procedures.

BRCA1/2 variants of unknown significance in hereditary breast and ovarian cancer (HBOC) syndrome: looking for the hidden meaning

Hereditary breast and ovarian cancer syndrome is caused by germline mutations in BRCA1/2 genes. These genes are very large and their mutations are heterogeneous and scattered throughout the coding sequence. In addition to the above-mentioned mutations, variants of uncertain/unknown significance (VUSs) have been identified in BRCA genes, which make more difficult the clinical management of the patient and risk assessment. In the last decades, several laboratories have developed different databases that contain more than 2000 variants for the two genes and integrated strategies which include multifactorial prediction models based on direct and indirect genetic evidence, to classify the VUS and attribute them a clinical significance associated with a deleterious, high-low or neutral risk. This review provides a comprehensive overview of literature studies concerning the VUSs, in order to assess their impact on the population and provide new insight for the appropriate patient management in clinical practice.

Clinical management among individuals with variant of uncertain significance in hereditary cancer: A systematic review and meta-analysis

Improper medical use of variant of uncertain significance (VUS) remains a concern in hereditary cancer genetic testing. The goal of this study was to assess the association between pathogenic and likely pathogenic (P/LP), VUS, and benign and likely benign (B/LB) genetic test results and cancer-related surgical and screening management. Systematic searches of Medline, Embase, EBSCO CINAHL Plus, and PsycINFO were conducted from 1946 to August 26, 2020. Eligible studies included individuals with cancer genetic test result and surgical or screening management outcomes. We reviewed 885 abstracts and 22 studies that reported relevant surgical and screening outcomes were included. Meta-analysis revealed significantly higher surgical rates among individuals with P/LP than among those with VUS for therapeutic mastectomy with contralateral prophylactic mastectomy (OR = 7.35, 95% CI, 4.14-13.64), prophylactic mastectomy (OR = 3.05, 95% CI, 1.5-6.19), and oophorectomy (OR = 6.46, 95% CI, 3.64-11.44). There were no significant differences in therapeutic mastectomy, or breast conservation or lumpectomy rates between individuals with P/LP and VUS, or in any outcomes between patients with VUS and B/LB. Studies evaluating screening outcomes were limited, and results were conflicting. Comprehensive analysis do not indicate that a significant number of individuals with VUS results undergo inappropriate clinical management.

Cancer Health Assessments Reaching Many (CHARM): A clinical trial assessing a multimodal cancer genetics services delivery program and its impact on diverse populations

Advances in the application of genomic technologies in clinical care have the potential to increase existing healthcare disparities. Studies have consistently shown that only a fraction of eligible patients with a family history of cancer receive recommended cancer genetic counseling and subsequent genetic testing. Care delivery models using pre-test and post-test counseling are not scalable, which contributes to barriers in accessing genetics services. These barriers are even more pronounced for patients in historically underserved populations. We have designed a multimodal intervention to improve subsequent cancer surveillance, by improving the identification of patients at risk for familial cancer syndromes, reducing barriers to genetic counseling/testing, and increasing patient understanding of complex genetic results. We are evaluating this intervention in two large, integrated healthcare systems that serve diverse patient populations (NCT03426878). The primary outcome is the number of diagnostic (hereditary cancer syndrome) findings. We are examining the clinical and personal utility of streamlined pathways to genetic testing using electronic medical record data, surveys, and qualitative interviews. We will assess downstream care utilization of individuals receiving usual clinical care vs. genetic testing through the study. We will evaluate the impacts of a literacy-focused genetic counseling approach versus usual care genetic counseling on care utilization and participant understanding, satisfaction, and family communication. By recruiting participants belonging to historically underserved populations, this study is uniquely positioned to evaluate the potential of a novel genetics care delivery program to reduce care disparities.

Analysis of BRCA1/2 variants of unknown significance in the prospective Korean Hereditary Breast Cancer study

Genetic testing for BRCA1 and BRCA2 is crucial in diagnosing hereditary breast and ovarian cancer syndromes and has increased with the development of multigene panel tests. However, results classified as variants of uncertain significance (VUS) present challenges to clinicians in attempting to choose an appropriate management plans. We reviewed a total of 676 breast cancer patients included in the Korean Hereditary Breast Cancer (KOHBRA) study with a VUS on BRCA mutation tests between November 2007 and April 2013. These results were compared to the ClinVar database. We calculated the incidence and odds ratios for these variants using the Korean Reference Genome Database. A total of 58 and 91 distinct VUS in BRCA1 and BRCA2 were identified in the KOHBRA study (comprising 278 and 453 patients, respectively). A total of 27 variants in the KOHBRA study were not registered in the Single Nucleotide Polymorphism database. Among BRCA1 VUSs, 20 were reclassified as benign or likely benign, four were reclassified as pathogenic or likely pathogenic, and eight remained as VUSs according to the ClinVar database. Of the BRCA2 VUSs, 25 were reclassified as benign or likely benign, two were reclassified as pathogenic or likely pathogenic, and 33 remained as VUS according to the ClinVar database. There were 12 variants with conflicting interpretations of pathogenicity for BRCA1 and 18 for BRCA2. Among them, p.Leu1780Pro showed a particularly high odds ratio. Six pathogenic variants and one conflicting variant identified using ClinVar could be reclassified as pathogenic variants in this study. Using updated ClinVar information and calculating odds ratios can be helpful when reclassifying VUSs in BRCA1/2.

A novel BRCA2 splice variant identified in a young woman

Background

BRCA1/2 VUSs represent an important clinical issue in risk assessment for the breast/ovarian cancer families (HBOC) families. Among them, some occurring within the intron‐exon boundary may lead to aberrant splicing process by altering or creating de novo splicing regulatory elements or unmasking cryptic splice site. Defining the impact of these potential splice variants at functional level is important to establish their pathogenic role.

Methods

Genomic DNA was extracted from peripheral blood sample of a young woman affected with breast cancer belonging to a HBOC family and the entire coding regions of the BRCA1 and BRCA2 genes were amplified using the Ion AmpliSeq BRCA1 and BRCA2 Panel. The BRCA2 c.682‐2delA variant has been characterized by RT‐PCR analysis performed on mRNA extracted from blood and lymphoblastoid cell line.

Results

We demonstrated that a novel BRCA2 c.682‐2delA variant at the highly conserved splice consensus site in intron 8 disrupts the canonical splice acceptor site generating a truncated protein as predicted by several bioinformatics tools. Segregations analysis in the family and LOH performed on proband breast cancer tissue further confirmed its classification as pathogenic variant.

Conclusion

Combining different methodologies, we characterized this new BRCA2 variant and provided findings of clinical utility for its classification as pathogenic variant.

PARP inhibitors and epithelial ovarian cancer: Molecular mechanisms, clinical development and future prospective

Epithelial ovarian cancer (EOC) has a poor prognosis. Since the introduction of paclitaxel as antineoplastic agent >20 years ago, only a few phase III randomized trials have shown challenging data regarding different therapeutic options for facing its aggressive clinical course and granting active therapies to patients. Different studies have shown the utility of poly(ADP-ribose) polymerase (PARP) inhibitors in women with EOC with or without BRCA mutations, both germline and somatic. Three PARP inhibitors, olaparib, rucaparib and niraparib, have been recently approved by the Food and Drug Administration for clinical use in EOC patients, though with different clinical indications and profiles of toxicity, while two other molecules, veliparib and talazoparib, are still under clinical investigation. The aim of the present paper is to evaluate the current status of PARP inhibitors in terms of molecular activity, pharmacodynamic properties and clinical applications.

The Community Oncology and Academic Medical Center Alliance in the Age of Precision Medicine: Cancer Genetics and Genomics Considerations

Recent public policy, governmental regulatory and economic trends have motivated the establishment and deepening of community health and academic medical center alliances. Accordingly, community oncology practices now deliver a significant portion of their oncology care in association with academic cancer centers. In the age of precision medicine, this alliance has acquired critical importance; novel advances in nucleic acid sequencing, the generation and analysis of immense data sets, the changing clinical landscape of hereditary cancer predisposition and ongoing discovery of novel, targeted therapies challenge community-based oncologists to deliver molecularly-informed health care. The active engagement of community oncology practices with academic partners helps with meeting these challenges; community/academic alliances result in improved cancer patient care and provider efficacy. Here, we review the community oncology and academic medical center alliance. We examine how practitioners may leverage academic center precision medicine-based cancer genetics and genomics programs to advance their patients' needs. We highlight a number of project initiatives at the City of Hope Comprehensive Cancer Center that seek to optimize community oncology and academic cancer center precision medicine interactions.

"It wasn't just for me": Motivations and implications of genetic testing for women at a low risk of hereditary breast and ovarian cancer syndrome

OBJECTIVE

Genetic testing for hereditary breast and ovarian cancer (HBOC) due to pathogenic variants in BRCA1 or BRCA2 is why most women present to familial cancer centers. Despite being assessed as low risk for HBOC, many women proceed with genetic testing. This study explored the genetic testing experiences of unaffected women at low risk of HBOC to clarify what motivates these women to have testing, and what are the implications of the results.

METHODS

A qualitative approach was taken. Participants included women who had genetic testing for HBOC from 2016-2018 at the Parkville Familial Cancer Centre in Melbourne, Australia. In-depth, semi-structured interviews were conducted, and thematic analysis was undertaken on transcripts; transcripts were coded, codes were organized into a hierarchical system of categories/subcategories, and key themes were identified.

RESULTS

Analysis of 19 transcripts identified five themes: family underpinned all motivators for HBOC genetic testing; health professionals were influential throughout the process; participants were planning for a positive result; results influenced screening-anxiety and frequency; and negative results gave participants relief in many different ways. The three participants with positive results reported feeling shocked at the results and empowered giving this information to family members.

CONCLUSIONS

Women at low HBOC risk may be motivated to seek genetic testing, and access to this is increasingly offered through non-genetic health professionals. Professionals can support clients through genetic testing by recognizing familial experiences, providing accurate information, addressing risk perceptions, and understanding cancer anxiety felt by many women.

Patients' views on variants of uncertain significance across indications

As genomic sequencing expands into more areas of patient care, an increasing number of patients learn of the variants of uncertain significance (VUSs) that they carry. Understanding the potential psychosocial consequences of the disclosure of a VUS can help inform pre- and post-test counseling discussions. Medical uncertainty in general elicits a variety of responses from patients, particularly in the growing field of medical genetics and genomics. It is important to consider patients' responses to the ambiguous nature of VUSs across different indications and situational contexts. Genetic counselors and other providers ordering genetic testing should be prepared for the possibility of their patients' misinterpretation of such results. Pre-test counseling should include a discussion of the possibility of VUSs and what it would mean for the patient's care and its potential psychosocial impacts. When a VUS is found, post-test counseling should include additional education and a discussion of the variant's implications and medical management recommendations based on the results. These discussions may help temper subjective interpretations, unrealistic views, and decisional regret.

A Review of Precision Oncology Knowledgebases for Determining the Clinical Actionability of Genetic Variants

The increased availability of tumor genetic testing and targeted cancer therapies contributes to the advancement of precision medicine in the field of oncology. Precision oncology knowledgebases provide a way of organizing clinically relevant genetic information in a way that is easily accessible for both oncologists and patients, facilitating the genetic-based clinical decision making. Many organizations and companies have built precision oncology knowledgebases, intended for multiple users. In general, these knowledgebases offer information on cancer-related genetic variants as well as their associated diagnostic, prognostic, and therapeutic implications, but they often differ in their information curations, designs, and user experiences. It is advisable that oncologists use multiple knowledgebases during their practice to have them complement each other. In the future, convergence toward common standards and formats is needed to ensure that the comprehensive knowledge across all sources can be unified to bring the oncology community closer to the achievement of the goal of precision oncology.

Adult patients with undiagnosed conditions and their responses to unresolved uncertainty from exome sequencing

Patients pursuing exome sequencing (ES) in their quest for diagnosis will most often experience unresolved uncertainty from their ES results because the majority of ES results are non-diagnostic. This study explored and compared the experiences of receiving two types of ES results that may result in diagnostic uncertainty. Semi-structured phone interviews were conducted with 23 adult patients with undiagnosed conditions who received either a negative result or a result with one or more variants of uncertain significance (VUSs) from ES. Interviews were transcribed and subjected to thematic and comparative analyses. Participants accurately understood their results and described various sources of genomic uncertainty including probability, complexity, and ambiguity. Their acclimation to illness uncertainty resulted in realistic expectations about and acceptance of their results. Participants still hoped that ES would end their diagnostic odyssey. Hope and optimism were used to cope with continued uncertainty. No thematic differences were found between the experiences of those who received negative results versus those who received VUSs. Our findings may inform clinical practices of informed consent and disclosure of negative results and VUSs through a greater consideration of patients' reactions, concerns, and challenges with adaptation to uncertainty.

Germline variants in cancer genes in high-risk non-BRCA patients from Puerto Rico

Inherited pathogenic variants in genes that confer moderate to high risk of breast cancer may explain up to 50% of familial breast cancer. This study aimed at identifying inherited pathogenic variants in breast cancer cases from Puerto Rico that were not linked to BRCA1 or BRCA2. Forty-eight breast cancer patients that met the clinical criteria for BRCA testing but had received a negative BRCA1/2 result were recruited. Fifty-three genes previously implicated in hereditary cancer predisposition were captured using the BROCA Agilent cancer risk panel followed by massively parallel sequencing. Missense variants of uncertain clinical significance in CHEK2 were evaluated using an in vitro kinase assays to determine their impact on function. Pathogenic variants were identified in CHEK2, MUTYH, and RAD51B in four breast cancer patients, which represented 8.3% of the cohort. We identified three rare missense variants of uncertain significance in CHEK2 and two variants (p.Pro484Leu and p.Glu239Lys) showed markedly decreased kinase activity in vitro comparable to a known pathogenic variant. Interestingly, the local ancestry at the RAD51B locus in the carrier of p.Arg47* was predicted to be of African origin. In this cohort, 12.5% of the BRCA-negative breast cancer patients were found to carry a known pathogenic variant or a variant affecting protein activity. This study reveals an unmet clinical need of genetic testing that could benefit a significant proportion of at-risk Latinas. It also highlights the complexity of Hispanic populations as pathogenic factors may originate from any of the ancestral populations that make up their genetic backgrounds.

Genetic Testing: Consent and Result Disclosure for Primary Care Providers

Historically, both pretest and posttest genetic counseling has been standard of care for genetic testing. This model should be adapted for primary care providers (PCPs) willing to learn critical information about the test and key concepts that patients need to make an informed testing decision. It is helpful for PCPs to discuss a few initial patients with a genetic counselor to prepare for the key concepts of pretest and posttest counseling. This article provides guidance about the recommended level of involvement of PCPs based on the test indication, test complexity, disorder management, and the potential for psychosocial sequela.

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.

A Functional Analysis of the Unclassified Pro2767Ser BRCA2 Variant Reveals Its Potential Pathogenicity that Acts by Hampering DNA Binding and Homology-Mediated DNA Repair

BRCA1 and BRCA2 are the genes most frequently associated with hereditary breast and ovarian cancer (HBOC). They are crucial for the maintenance of genome stability, particularly in the homologous recombination-mediated repair pathway of DNA double-strand breaks (HR-DSBR). Widespread BRCA1/2 next-generation sequencing (NGS) screening has revealed numerous variants of uncertain significance. Assessing the clinical significance of these variants is challenging, particularly regarding the clinical management of patients. Here, we report the functional characterization of the unclassified BRCA2 c.8299C > T variant, identified in a young breast cancer patient during BRCA1/2 NGS screening. This variant causes the change of Proline 2767 to Serine in the DNA binding domain (DBD) of the BRCA2 protein, necessary for the loading of RAD51 on ssDNA during the HR-DSBR. Our in silico analysis and 3D-structure modeling predicted that the p.Pro2767Ser substitution is likely to alter the BRCA2 DBD structure and function. Therefore, to evaluate the functional impact of the p.Pro2767Ser variant, we used a minigene encoding a truncated protein that contains the BRCA2 DBD and the nearby nuclear localization sequence. We found that the ectopically expressed truncated protein carrying the normal DBD, which retains the DNA binding function and lacks the central RAD51 binding domain, interferes with endogenous wild-type BRCA2 mediator functions in the HR-DSBR. We also demonstrated that the BRCA2 Pro2767Ser DBD is unable to compete with endogenous BRCA2 DNA binding, thereby suggesting that the p.Pro2767Ser substitution in the full-length protein causes the functional loss of BRCA2. Consequently, our data suggest that the p.Pro2767Ser variant should be considered pathogenic, thus supporting a revision of the ClinVar interpretation. Moreover, our experimental strategy could be a valid method with which to preliminarily evaluate the pathogenicity of the unclassified BRCA2 germline variants in the DBD and their risk of predisposing to HBOC.

Novel mutations in actionable breast cancer genes by targeted sequencing in an ethnically homogenous cohort

Background

Genetic testing is becoming an essential tool for breast cancer (BC) diagnosis and treatment pathway, and particularly important for early detection and cancer prevention. The purpose of this study was to explore the diagnostic yield of targeted sequencing of the high priority BC genes.

Methods

We have utilized a cost-effective targeted sequencing approach of high priority actionable BC genes (BRCA1, BRCA2, ERBB2 and TP53) in a homogeneous patient cohort from Bangladesh (n = 52) by using tumor and blood samples.

Results

Blood derived targeted sequencing revealed 25.58% (11/43) clinically relevant mutations (both pathogenic and variants of uncertain significance (VUS)), with 13.95% (6/43) of samples carrying a pathogenic mutations. We have identified and validated five novel pathogenic germline mutations in this cohort, comprising of two frameshift deletions in BRCA2, and missense mutations in BRCA1, BRCA2 and ERBB2 gene respectively. Furthermore, we have identified three pathogenic mutations and a VUS within three tumor samples, including a sample carrying pathogenic mutations impacting both TP53 (c.322dupG; a novel frameshift insertion) and BRCA1 genes (c.116G > A). 22% of tissue samples had a clinically relevant TP53 mutation. Although the cohort is small, we have found pathogenic mutations to be enriched in BRCA2 (9.30%, 4/43) compare to BRCA1 (4.65%, 2/43). The frequency of germline VUS mutations found to be similar in both BRCA1 (4.65%; 2/43) and BRCA2 (4.65%; 2/43) compared to ERBB2 (2.32%; 1/43).

Conclusions

This is the first genetic study of BC predisposition genes in this population, implies that genetic screening through targeted sequencing can detect clinically significant and actionable BC-relevant mutations.

Electronic supplementary material

The online version of this article (10.1186/s12881-019-0881-0) contains supplementary material, which is available to authorized users.

The influence of BRCA variants of unknown significance on cancer risk management decision-making

OBJECTIVE

To compare gynecological cancer risk management between women with BRCA variants of unknown significance (VUS) to women with negative genetic testing.

METHODS

Ninety-nine patients whose BRCA genetic testing yielded VUS were matched with 99 control patients with definitive negative BRCA results at a single institution. Demographics and risk management decisions were obtained through chart review. Primary outcome was the rate of risk-reducing bilateral salpingo-oophorectomy (RRBSO). Chi square tests, t-tests, and logistic regression were performed, with significance of p<0.05.

RESULTS

VUS patients were more likely to be non-Caucasian (p=0.000) and of Ashkenazi-Jewish descent (p=0.000). There was no difference in gynecologic oncology referrals or recommendations to screen or undergo risk-reducing surgery for VUS vs. negative patients. Ultimately, 44 patients (22%) underwent RRBSO, with no significant difference in surgical rate based on the presence of VUS. Ashkenazi-Jewish descent was associated with a 4.5 times increased risk of RRBSO (OR=4.489; 95% CI=1.484-13.579) and family history of ovarian cancer was associated with a 2.6 times risk of RRBSO (OR=2.641; 95% CI=1.107-6.299).

CONCLUSION

In our institution, patients with VUS were surgically managed similarly to those with negative BRCA testing. The numbers of patients with VUS are likely to increase with the implementation of multi-gene panel testing. Our findings underscore the importance of genetic counseling and individualized screening and prevention strategies in the management of genetic testing results.

Understanding variants of uncertain significance in the era of multigene panels: Through the eyes of the patient

Variants of uncertain significance (VUSs) are often disclosed to patients despite ambiguous association with disease risk and lack of clinical actionability. It is important to understand how patients understand a VUS result, but few studies have assessed this. Our qualitative study explored patient recall, reaction to, and interpretation of a VUS in the context of multigene panels. We conducted 11 semi-structured phone interviews with adults who had a VUS identified on multigene panel testing in a hereditary oncology clinic, with questions focusing on the VUS result, personal and family history, and motivations for and expectations of genetic testing. Transcripts were coded iteratively, using both deductive and inductive codes. Overall, participants usually recalled that they had a VUS, despite variation in the vocabulary used. Participants responded both emotionally and intellectually to receiving information about having a VUS, which was often a result of their expectations and motivations prior to testing. Overall, participants understood the lack of clinical significance of a VUS, yet often interpreted the etiologic significance of a VUS within the context of the personal and family history. Our study provides insight into a process by which patients translate uncertain genetic testing results into a construct that fits within their current belief framework and which may be facilitated by a genetic counselor.

Consent and Autonomy in the Genomics Era

PURPOSE OF REVIEW

Genomic tests offer increased opportunity for diagnosis, but their outputs are often uncertain and complex; results may need to be revised and/or may not be relevant until some future time. We discuss the challenges that this presents for consent and autonomy.

RECENT FINDINGS

Popular discourse around genomic testing tends to be strongly deterministic and optimistic, yet many findings from genomic tests are uncertain or unclear. Clinical conversations need to anticipate and potentially challenge unrealistic expectations of what a genomic test can deliver in order to enhance autonomy and ensure that consent to genomic testing is valid.

SUMMARY

We conclude that 'fully informed' consent is often not possible in the context of genomic testing, but that an open-ended approach is appropriate. We consider that such broad consent can only work if located within systems or organisations that are trustworthy and that have measures in place to ensure that such open-ended agreements are not abused. We suggest that a relational concept of autonomy has benefits in encouraging focus on the networks and relationships that allow decision making to flourish.

Psychosocial Effects of Multigene Panel Testing in the Context of Cancer Genomics

In recent years, with both the development of next-generation sequencing approaches and the Supreme Court decision invalidating gene patents, declining costs have contributed to the emergence of a new model of hereditary cancer genetic testing. Multigene panel testing (or multiplex testing) involves using next-generation sequencing technology to determine the sequence of multiple cancer-susceptibility genes. In addition to high-penetrance cancer-susceptibility genes, multigene panels frequently include genes that are less robustly associated with cancer predisposition. Scientific understanding about associations between many specific moderate-penetrance gene variants and cancer risks is incomplete. The emergence of multigene panel tests has created unique challenges that may have meaningful psychosocial implications. Contrasted with the serial testing process, wherein patients consider the personal and clinical implications of each evaluated gene, with multigene panel testing, patients provide broad consent to whichever genes are included in a particular panel and then, after the test, receive in-depth genetic counseling to clarify the distinct implications of their specific results. Consequently, patients undergoing multigene panel testing may have a less nuanced understanding of the test and its implications, and they may have fewer opportunities to self-select against the receipt of particular types of genetic-risk information. Evidence is conflicting regarding the emotional effects of this testing.

Physician interpretation of variants of uncertain significance

A growing number of physicians will interact with genetic test results as testing becomes more commonplace. While variants of uncertain significance can complicate results, it is equally important that physicians understand how to incorporate these results into clinical care. An online survey was created to assess physician self-reported comfort level with genetics and variants of uncertain significance. Physicians were asked to respond to three case examples involving genetic test results. The survey was sent to 488 physicians at Mayo Clinic FL on 8/16/2017. Physicians from all specialties were invited to participate. A total of 92 physicians responded to the survey. Only 13/84 (14.6%) responded to all three case examples with the answer deemed "most correct" by review of literature. Physicians that specialized in cancer were more likely to answer questions appropriately (P = .02). Around half (39/84) of the physicians incorrectly defined a variant of uncertain significance (VUS). Over 75% made a recommendation for genetic testing that was not warranted. Many physicians have never received formal genetics training; however, they will be expected to provide an accurate explanation of the genetic test results and subsequent evidence-based medical management recommendations. These results demonstrate that a substantial proportion of physicians lack a true understanding of the implications a VUS. Utilization of supplemental genetics training programs coupled with increase awareness of genetic services may help to improve patient care.

Clinical validity assessment of genes for inclusion in multi-gene panel testing: A systematic approach

BACKGROUND

Advances in sequencing technology have led to expanded use of multi-gene panel tests (MGPTs) for clinical diagnostics. Well-designed MGPTs must balance increased detection of clinically significant findings while mitigating the increase in variants of uncertain significance (VUS). To maximize clinical utililty, design of such panels should include comprehensive gene vetting using a standardized clinical validity (CV) scoring system.

METHODS

To assess the impact of CV-based gene vetting on MGPT results, data from MGPTs for cardiovascular indications were retrospectively analyzed. Using our CV scoring system, genes were categorized as having definitive, strong, moderate, or limited evidence. The rates of reported pathogenic or likely pathogenic variants and VUS were then determined for each CV category.

RESULTS

Of 106 total genes, 42% had definitive, 17% had strong, 29% had moderate, and 12% had limited CV. The detection rate of variants classified as pathogenic or likely pathogenic was higher for genes with greater CV, while the VUS rate showed an inverse relationship with CV score. No pathogenic or likely pathogenic findings were observed in genes with a limited CV.

CONCLUSION

These results demonstrate the importance of a standardized, evidence-based vetting process to establish CV for genes on MGPTs. Using our proposed system may help to increase the detection rate while mitigating higher VUS rates.

Germline and Somatic Tumor Testing in Gynecologic Cancer Care

New technologies have advanced the science of tumor biology and genomics. Commercially available germline and somatic testing modalities have the downstream benefits of enabling prevention strategies in women with hereditary cancers and their family members in addition to identifying women who benefit most from novel targeted therapeutics. The matrix of available testing is complex and evolving. Women's health providers need to be versed in benefits and limitations of available testing. Genetic counselors play a pivotal role in interpretation of relevant mutations, and in avoiding common pitfalls, but their skill set is not sufficient to optimally integrate cancer genomics into clinical practice.

Selecting variants of unknown significance through network-based gene-association significantly improves risk prediction for disease-control cohorts

Variants of unknown/uncertain significance (VUS) pose a huge dilemma in current genetic variation screening methods and genetic counselling. Driven by methods of next generation sequencing (NGS) such as whole exome sequencing (WES), a plethora of VUS are being detected in research laboratories as well as in the health sector. Motivated by this overabundance of VUS, we propose a novel computational methodology, termed VariantClassifier (VarClass), which utilizes gene-association networks and polygenic risk prediction models to shed light into this grey area of genetic variation in association with disease. VarClass has been evaluated using numerous validation steps and proves to be very successful in assigning significance to VUS in association with specific diseases of interest. Notably, using VUS that are deemed significant by VarClass, we improved risk prediction accuracy in four large case-studies involving disease-control cohorts from GWAS as well as WES, when compared to traditional odds ratio analysis. Biological interpretation of selected high scoring VUS revealed interesting biological themes relevant to the diseases under investigation. VarClass is available as a standalone tool for large-scale data analyses, as well as a web-server with additional functionalities through a user-friendly graphical interface.

Patients' perspectives of variants of uncertain significance and strategies for uncertainty management

Variants of uncertain significance (VUS) are a well-recognized source of uncertainty in genomic medicine. Despite the existence of straightforward clinical management recommendations, patients report feeling anxiety, worry, and uncertainty in response to VUS. We report the first structured analysis of patient perspectives of VUS-related uncertainty in genome sequencing using Han's taxonomy of genomic uncertainty. We conducted in-depth semi-structured interviews with 11 patients to elicit their thoughts regarding implications of the result for themselves and their family members. Patients' primary concern with VUS-related uncertainty involved personal and practical issues as they directly inform health-care decisions. Patients demonstrated good understanding of the epistemic nature of VUS uncertainty-that information about such variant is currently unknown. However, between-provider discordance in explanations of the implication of this uncertainty for patients' diagnosis, prognosis, and therapy was a major contributor to the overall experience of uncertainty. Strategies for uncertainty reduction involved periodically checking back for reclassification and receiving concordant and clear recommendation from providers. Other proactive strategies of uncertainty reduction-such as information seeking and reading the genetic test report-were not helpful. Collectively, these findings offer previously unreported insight into uncertainty management strategies used by patients which have the potential to guide clinical management practices.

Shared decision making: Implications for return of results from whole-exome and whole-genome sequencing

In this issue, Kaphingst and colleagues report on young breast cancer patient's preferences for learning about various results from genomic sequencing. In our commentary, we discuss the results in light of the burgeoning clinical use of whole-exome and whole-genome sequencing (WES/WGS). In particular, we consider findings in the context of a Shared Decision Making approach to return of results. We also identify additional important factors to consider that may influence patient preferences that were largely absent from the paper by Kaphingst and colleagues, including cultural context, costs of testing, and provider factors.