Time to incorporate germline multigene panel testing into breast and ovarian cancer patient care

Variant-specific Mendelian Risk Prediction Model

Many pathogenic sequence variants (PSVs) have been associated with increased risk of cancers. Mendelian risk prediction models use Mendelian laws of inheritance to predict the probability of having a PSV based on family history, as well as specified PSV frequency and penetrance (agespecific probability of developing cancer given genotype). Most existing models assume penetrance is the same for any PSVs in a certain gene. However, for some genes (for example, BRCA1/2), cancer risk does vary by PSV. We propose an extension of Mendelian risk prediction models to relax the assumption that risk is the same for any PSVs in a certain gene by incorporating variant-specific penetrances and illustrating these extensions on two existing Mendelian risk prediction models, BRCAPRO and PanelPRO. Our proposed BRCAPRO-variant and PanelPRO-variant models incorporate variant-specific BRCA1/2 PSVs through the region classifications. Due to the sparsity of the variant information we classify BRCA1/2 PSVs into three regions; the breast cancer clustering region (BCCR), the ovarian cancer clustering region (OCCR), and an other region. Simulations were conducted to evaluate the performance of the proposed BRCAPRO-variant model compared to the existing BRCAPRO model which assumes the penetrance is the same for any PSVs in BRCA1 (and respectively BRCA2). Simulation results showed that the BRCAPRO-variant model was well calibrated to predict region-specific BRCA1/2 carrier status with high discrimination and accuracy on the region-specific level. In addition, we showed that the BRCAPRO-variant model achieved performance gains over the existing risk prediction models in terms of calibration without loss in discrimination and accuracy. We also evaluated the performance of the two proposed models, BRCAPRO-variant and PanelPRO-variant, on a cohort of 1,961 families from the Cancer Genetics Network (CGN). We showed that our proposed models provide region-specific PSV carrier probabilities with high accuracy, while the calibration, discrimination and accuracy of gene-specific PSV carrier probabilities were comparable to the existing gene-specific models. As more variant-specific PSV penetrances become available, we have shown that Mendelian risk prediction models can be extended to integrate the additional information, providing precise variant or region-specific PSV carrier probabilities and improving future cancer risk predictions.

Assessment of a Peer Physician Coaching Partnership Between a Designated Cancer Center Genetics Service and a Community Cancer Network Hospital

BACKGROUND

Patients with cancer seen in rural and underserved areas disproportionately face barriers to access genetic services. Genetic testing is critical to inform treatment decisions, for early detection of another cancer, and to identify at-risk family members who may benefit from screening and prevention.

OBJECTIVE

To examine medical oncologists' genetic testing ordering trends for patients with cancer.

DESIGN, SETTING, AND PARTICIPANTS

This prospective quality improvement study was performed in 2 phases over 6 months between August 1, 2020, and January 31, 2021, at a community network hospital. Phase 1 focused on observation of clinic processes. Phase 2 incorporated peer coaching from cancer genetics experts for medical oncologists at the community network hospital. The follow-up period lasted 9 months.

MAIN OUTCOMES AND MEASURES

The number of genetic tests ordered was compared between phases.

RESULTS

The study included 634 patients (mean [SD] age, 71.0 [10.8] years [range, 39-90 years]; 409 women [64.5%]; 585 White [92.3%]); 353 (55.7%) had breast cancer, 184 (29.0%) had prostate cancer, and 218 (34.4%) had a family history of cancer. Of the 634 patients with cancer, 29 of 415 (7.0%) received genetic testing in phase 1, and 25 of 219 (11.4%) received genetic testing in phase 2. Of the 29 patients who received testing in phase 1, 20 (69.0%) had germline genetic testing; 23 of 25 patients (92.0%) had germline genetic testing in phase 2. Uptake of germline genetic testing increased by 23.0% between phases, but the difference was not statistically significant (P = .06). Uptake of germline genetic testing was highest among patients with pancreatic cancer (4 of 19 [21.1%]) and ovarian cancer (6 of 35 [17.1%]); the National Comprehensive Cancer Network (NCCN) recommends offering genetic testing to all patients with pancreatic cancer and ovarian cancer.

CONCLUSIONS AND RELEVANCE

This study suggests that peer coaching from cancer genetics experts was associated with an increase in ordering of genetic testing by medical oncologists. Efforts made to (1) standardize gathering of personal and family history of cancer, (2) review biomarker data suggestive of a hereditary cancer syndrome, (3) facilitate ordering tumor and/or germline genetic testing every time NCCN criteria are met, (4) encourage data sharing between institutions, and (5) advocate for universal coverage for genetic testing may help realize the benefits associated with precision oncology for patients and their families seeking care at community cancer centers.

Germline Mutations Landscape in a Cohort of the State of Minas Gerais, Brazil, in Patients Who Underwent Genetic Counseling for Gynecological and Breast Cancer

OBJECTIVE

 The present study evaluated the profile of germline mutations present in patients who underwent genetic counseling for risk assessment for breast cancer (BC), ovarian cancer (OC), and endometrial cancer (EC) with a possible hereditary pattern.

METHODS

 Medical records of 382 patients who underwent genetic counseling after signing an informed consent form were analyzed. A total of 55.76% of patients (213/382) were symptomatic (personal history of cancer), and 44.24% (169/382) were asymptomatic (absence of the disease). The variables analyzed were age, sex, place of birth, personal or family history of BC, OC, EC, as well as other types of cancer associated with hereditary syndromes. The Human Genome Variation Society (HGVS) nomenclature guidelines were used to name the variants, and their biological significance was determined by comparing 11 databases.

RESULTS

 We identified 53 distinct mutations: 29 pathogenic variants, 13 variants of undetermined significance (VUS), and 11 benign. The most frequent mutations were BRCA1 c.470_471delCT, BRCA1 c.4675 + 1G > T, and BRCA2 c.2T> G. Furthermore, 21 variants appear to have been described for the first time in Brazil. In addition to BRCA1/2 mutations, variants in other genes related to hereditary syndromes that predispose to gynecological cancers were found.

CONCLUSION

 This study allowed a deeper understanding of the main mutations identified in families in the state of Minas Gerais and demonstrates the need to assess the family history of non-gynecological cancer for risk assessment of BC, OC, and EC. Moreover, it is an effort that contributes to population studies to evaluate the cancer risk mutation profile in Brazil.

Hereditary variants of unknown significance in African American women with breast cancer

Expanded implementation of genetic sequencing has precipitously increased the discovery of germline and somatic variants. The direct benefit of identifying variants in actionable genes may lead to risk reduction strategies such as increased surveillance, prophylactic surgery, as well as lifestyle modifications to reduce morbidity and mortality. However, patients with African ancestry are more likely to receive inconclusive genetic testing results due to an increased number of variants of unknown significance decreasing the utility and impact on disease management and prevention. This study examines whole exome sequencing results from germline DNA samples in African American women with a family history of cancer including 37 cases that were diagnosed with breast cancer and 51 family members. Self-identified ancestry was validated and compared to the 1000 genomes population. The analysis of sequencing results was limited to 85 genes from three clinically available common genetic screening platforms. This target region had a total of 993 variants of which 6 (<1%) were pathogenic or likely pathogenic, 736 (74.1%) were benign, and 170 (17.1%) were classified as a variant of unknown significance. There was an average of 3.4±1.8 variants with an unknown significance per individual and 85 of 88 individuals (96.6%) harbored at least one of these in the targeted genes. Pathogenic or likely pathogenic variants were only found in 6 individuals for the BRCA1 (p.R1726fs, rs80357867), BRCA2 (p.K589fs, rs397507606 & p.L2805fs, rs397507402), RAD50 (p.E995fs, rs587780154), ATM (p.V2424G, rs28904921), or MUTYH (p.G396D, rs36053993) genes. Strategies to functionally validate the remaining variants of unknown significance, especially in understudied and hereditary cancer populations, are greatly needed to increase the clinical utility and utilization of clinical genetic screening platforms to reduce cancer incidence and mortality.

DNA Repair Mechanisms, Protein Interactions and Therapeutic Targeting of the MRN Complex

Repair of a DNA double-strand break relies upon a pathway of proteins to identify damage, regulate cell cycle checkpoints, and repair the damage. This process is initiated by a sensor protein complex, the MRN complex, comprised of three proteins-MRE11, RAD50, and NBS1. After a double-stranded break, the MRN complex recruits and activates ATM, in-turn activating other proteins such as BRCA1/2, ATR, CHEK1/2, PALB2 and RAD51. These proteins have been the focus of many studies for their individual roles in hereditary cancer syndromes and are included on several genetic testing panels. These panels have enabled us to acquire large amounts of genetic data, much of which remains a challenge to interpret due to the presence of variants of uncertain significance (VUS). While the primary aim of clinical testing is to accurately and confidently classify variants in order to inform medical management, the presence of VUSs has led to ambiguity in genetic counseling. Pathogenic variants within MRN complex genes have been implicated in breast, ovarian, prostate, colon cancers and gliomas; however, the hundreds of VUSs within MRE11, RAD50, and NBS1 precludes the application of these data in genetic guidance of carriers. In this review, we discuss the MRN complex's role in DNA double-strand break repair, its interactions with other cancer predisposing genes, the variants that can be found within the three MRN complex genes, and the MRN complex's potential as an anti-cancer therapeutic target.

Barriers to genetic testing in clinical psychiatry and ways to overcome them: from clinicians' attitudes to sociocultural differences between patients across the globe

Genetic testing has evolved rapidly over recent years and new developments have the potential to provide insights that could improve the ability to diagnose, treat, and prevent diseases. Information obtained through genetic testing has proven useful in other specialties, such as cardiology and oncology. Nonetheless, a range of barriers impedes techniques, such as whole-exome or whole-genome sequencing, pharmacogenomics, and polygenic risk scoring, from being implemented in psychiatric practice. These barriers may be procedural (e.g., limitations in extrapolating results to the individual level), economic (e.g., perceived relatively elevated costs precluding insurance coverage), or related to clinicians' knowledge, attitudes, and practices (e.g., perceived unfavorable cost-effectiveness, insufficient understanding of probability statistics, and concerns regarding genetic counseling). Additionally, several ethical concerns may arise (e.g., increased stigma and discrimination through exclusion from health insurance). Here, we provide an overview of potential barriers for the implementation of genetic testing in psychiatry, as well as an in-depth discussion of strategies to address these challenges.

Identification of Novel Biomarkers and Candidate Drug in Ovarian Cancer

This paper investigates the expression of the CREB1 gene in ovarian cancer (OV) by deeply excavating the gene information in the multiple databases and the mechanism thereof. In short, we found that the expression of the CREB1 gene in ovarian cancer tissue was significantly higher than that of normal ovarian tissue. Kaplan–Meier survival analysis showed that the overall survival was significantly shorter in patients with high expression of the CREB1 gene than those in patients with low expression of the CREB1 gene, and the prognosis of patients with low expression of the CREB1 gene was better. The CREB1 gene may play a role in the occurrence and development of ovarian cancer by regulating the process of protein. Based on differentially expressed genes, 20 small-molecule drugs that potentially target CREB1 with abnormal expression in OV were obtained from the CMap database. Among these compounds, we found that naloxone has the greatest therapeutic value for OV. The high expression of the CREB1 gene may be an indicator of poor prognosis in ovarian cancer patients. Targeting CREB1 may be a potential tool for the diagnosis and treatment of OV.

Knowledge and psychosocial impact of genetic counseling and multigene panel testing among individuals with ovarian cancer

In a sample of individuals with ovarian cancer, we aimed to (a) identify factors associated with the psychosocial impact of genetic counseling and multigene panel testing, (b) identify factors associated with cancer genetics knowledge, and (c) summarize patient-reported recommendations to improve the genetic counseling and multigene panel testing process. Eligible participants in this secondary analysis of quantitative and qualitative survey data were English-speaking adults with ovarian cancer. Psychosocial impact was assessed using the Multidimensional Impact of Cancer Risk Assessment (MICRA) questionnaire. Knowledge of cancer genetics was assessed using the KnowGene scale. Significant predictors of MICRA and KnowGene scores were identified using multiple regression. Open-ended survey item responses were analyzed using conventional content analysis. Eighty-seven participants met eligibility criteria. A positive genetic test result was associated with greater adverse psychosocial impact (B = 1.13, p = 0.002). Older age (B = - 0.07, p = 0.044) and being a member of a minority racial or ethnic group (B = - 3.075, p = 0.033) were associated with lower knowledge, while a personal history of at least one other type of cancer (B = 1.975, p = 0.015) was associated with higher knowledge. In open-ended item responses, participants wanted clinicians to assist with family communication, improve result disclosure, and enhance patient and family understanding of results. A subset of individuals with ovarian cancer who receive a positive genetic test result may be at risk for adverse psychosocial outcomes. Tailored cancer genetics education is necessary to promote the equitable uptake of targeted ovarian cancer treatment and risk-reducing therapies. Interventions to enhance patient-clinician communication in this setting are a research priority.

The role of genomics in global cancer prevention

Despite improvements in the understanding of cancer causation, much remains unknown regarding the mechanisms by which genomic and non-genomic factors initiate carcinogenesis, drive cell invasion and metastasis, and enable cancer to develop. Technological advances have enabled the analysis of whole genomes, comprising thousands of tumours across populations worldwide, with the aim of identifying mutation signatures associated with particular tumour types. Large collaborative efforts have resulted in the identification and improved understanding of causal factors, and have shed light on new opportunities to prevent cancer. In this new era in cancer genomics, discoveries from studies conducted on an international scale can inform evidence-based strategies in cancer control along the cancer care continuum, from prevention to treatment. In this Review, we present the relevant history and emerging frontiers of cancer genetics and genomics from the perspective of global cancer prevention. We highlight the importance of local context in the adoption of new technologies and emergent evidence, with illustrative examples from worldwide. We emphasize the challenges in implementing important genomic findings in clinical settings with disparate resource availability and present a conceptual framework for the translation of such findings into clinical practice, and evidence-based policies in order to maximize the utility for a population.

Referencing BRCA in hereditary cancer risk discussions: In search of an anchor in a sea of uncertainty

As panel testing and exome sequencing are increasingly incorporated into clinical care, clinicians must grapple with how to communicate the risks and treatment decisions surrounding breast cancer genes beyond BRCA1 and BRCA2. In this paper, we examine clinicians' practice of employing BRCA1 and BRCA2 to help contextualize less certain genetic information regarding cancer risk and the possible implications of this practice for patients within the context of an exome sequencing study, NCGENES. We audio-recorded return of results appointments for 14 women who participated in NCGENES, previously had breast cancer, and were suspected of having a hereditary cancer predisposition. These patients were also interviewed four weeks later regarding their understanding of their results. We found that BRCA1 and BRCA2 were held as the gold standard, where clinicians compared what is known about BRCA to the limited understanding of other breast cancer-related genes. BRCA1 and BRCA2 were used as anchors to shape patients' understandings of genetic knowledge, risk, and management, illustrating how the information clinicians provide to patients may work as an external anchor. Yet, presenting BRCA1 and BRCA2 as a means of scientific reassurance can run the risk of patients conflating knowledge about certainty of risk with degree of risk after receiving a result for a moderate penetrance gene. This can be further complicated by misperceptions of the precision of cancer predictability attributed to these or other described 'cancer genes' in public media.

Informing models of cancer genetics care in the era of multigene panel testing with patient-led recommendations

The study describes patient-reported experiences and recommendations to improve the genetic counseling and multigene panel testing (MGPT) process. A descriptive mixed-method study with concurrently collected and integrated qualitative and quantitative data was conducted. Eligible participants were English-speaking adults with a breast or gynecologic cancer diagnosis who had received genetic counseling and testing with a MGPT from one Comprehensive Cancer Center. Satisfaction with the genetic counseling, genetic knowledge using a recently validated scale (KnowGene), the multidimensional impact of cancer risk assessment (MICRA), family communication, and the association with demographic factors were evaluated. To supplement the large quantitative data set, qualitative focus group responses and open-ended text items were collected. Univariate and multivariable associations between each outcome of interest and personal characteristics were assessed. Qualitative data were content-analyzed. 603 participants completed the survey (48% response rate) and 10 individuals participated in the focus groups. Participants were mostly Caucasian, educated with a college degree or more, and female with median age 58 (24-91), and 78% of participants had a breast cancer diagnosis. Of all individuals undergoing genetic testing using a MGPT, 13% had a pathogenic variant identified, and 30% had a variant of uncertain significance (VUS). Overall, participants reported satisfaction with the genetic counseling and testing process (mean 36.9 [SD 4.7]). On average, participants had 7 incorrect answers out of 19 on the genetic knowledge scale (mean 12.3 [SD 3.4]). MICRA scores showed overall low levels of distress and uncertainty, as well as positive experiences, with wide variability (median 17 [0-84]). Age, marital status, education level, type of cancer diagnosis, and genetic testing results were significantly associated with outcomes. Most participants communicated genetic testing results to mainly female first-degree relatives. A wide range of individual preferences affecting overall satisfaction, or suggestions for improvement were shared. As new models of streamlined cancer genetic services are being clinically implemented, approaches should continue to assess and tailor the process based on patients' informational and emotional needs.

Breast cancer risk assessment and management programs: A practical guide

Breast cancer risk assessment continues to evolve as emerging knowledge of breast cancer risk drivers and modifiers enables better identification of high-risk women who may benefit from increased screening or targeted risk-reduction protocols. The ongoing development of breast cancer Risk Assessment and Management Programs (RAMPs) presents an opportunity to decrease breast cancer disease incidence with evidence-based interventions. The goal of this review was to provide a practical guide for providers seeking to establish or update a breast cancer risk assessment and management program. We outline genetic/familial, personal, reproductive, and lifestyle-related factors while discussing the incorporation of risk modeling for precise risk estimate personalization. We further describe the process for determining a risk management plan: information gathering, generation of a risk profile, and articulation and implementation of risk reduction. We also include an overview of clinical workflows in breast cancer management programs and underlines the logistics of establishing a program as well as general principles for guiding the formulation of an individualized risk management plan. We discuss practical considerations, such as clinic structure and operation, allocation of resources, and patient education. Other critical aspects of program design, including identification of the target population, delineation of the core components of the clinical experience, definition of provider roles, description of referral mechanisms, and the launching of a marketing plan are also addressed. The process of risk assessment is both anxiety-provoking and empowering for women at increased risk. New knowledge has enabled strategies to both understand the risk and control it through evidence-based risk management. These benefits can now be realized by an increasing number of unaffected, high-risk patients collaborating with risk management practitioners. Continuation of these efforts will lead to further progress in both risk stratification and risk management of women at elevated breast cancer risk in the near future.

Risk-reducing mastectomy: a case series of 124 procedures in Brazilian patients

PURPOSE

Women with mutations in breast cancer predisposition genes have a significantly higher lifetime risk of developing breast cancer and can opt for risk-reducing mastectomy. Women with positive family history of cancer can also opt for prophylactic surgery as a preventive method in selected cases. Current studies showed reduced risk of developing breast cancer after prophylactic nipple-sparing mastectomy, however, despite the good clinical outcomes, one of the main concerns regarding nipple-sparing mastectomy (NSM) is the oncological safety of nipple-areola complex preservation. In this study, we aimed to evaluate the indications, complication rates, and unfavorable events of 62 Brazilian patients that underwent risk-reducing NSM from 2004 to 2018.

METHODS

Patient data were reviewed retrospectively and descriptive statistics were utilized to summarize the findings.

RESULTS

The mean patients age was 43.8 years. The main indication for risk-reducing NSM was the presence of pathogenic mutation (53.3%), followed by atypia or lobular carcinoma in situ (25.8), and family history of breast cancer and/or ovarian cancer (20.9%). There were four (3.2%) incidental diagnosis of ductal carcinoma in situ and one invasive ductal carcinoma (0.8%). From the 124 prophylactic NSM performed, two (1.6%) complications had occurred: one (0.8%) infection and one (0.8%) partial nipple necrosis. In a mean follow-up of 50 months, there was one (1.6%) newly diagnosed breast cancer in the 62 patients undergoing prophylactic NSM.

CONCLUSIONS

Our findings demonstrated efficacy and safety to perform NSM as prophylactic surgery with good oncological outcomes and low complication rates in a case series of Brazilian patients.

Germline and Somatic BRCA1/2 Mutations in 172 Chinese Women With Epithelial Ovarian Cancer

Objective: Despite several nationwide cohort studies of germline BRCA1/2 mutations and several small cohort studies of somatic BRCA1/2 mutations in Chinese epithelial ovarian cancer (EOC) patients, little is known about the impact of these findings on survival outcomes in this population. In this study of 172 retrospectively recruited Chinese EOC patients, germline and somatic BRCA1/2 mutations and their value for predicting survival outcomes were evaluated.

Methods: Unselected patients who visited the study center from January 1, 2011, to January 1, 2015, were recruited and asked to provide peripheral blood samples for this study if they were pathologically confirmed to have primary EOC. All patients received staging surgeries or debulking surgeries involving systemic platinum-based chemotherapy, and the patients were then followed up to December 1, 2017. DNA was extracted from formalin-fixed, paraffin-embedded (FFPE) sections and peripheral blood and sequenced for somatic and germline testing, respectively. The demographic and clinicopathological characteristics of the patients were collected to analyze the distribution of BRCA mutations in subgroups. Survival outcomes were compared among various BRCA mutation statuses using univariate and multivariate models.

Results: In 58 (33.7%) patients, 63 variants were identified, including variants of unknown significance (VUS) in 18 patients (10.5%) and pathogenic or likely pathogenic variants in a partially overlapping set of 41 patients (23.8%). Germline BRCA mutations, somatic BRCA mutations, BRCA1 mutations in general, and BRCA2 mutations in general were found in 35 (20.3%), 7 (4.1%), 28 (16.3%), and 13 (7.6%) patients, respectively. Five recurrent mutations were identified. Personal and family cancer histories as well as hereditary breast and ovarian cancer (HBOC) criteria were associated with deleterious BRCA mutations both overall and in the germline specifically, whereas only age at diagnosis of EOC was associated with somatic BRCA mutations. In univariate and Cox regression analyses, patients with BRCA1/2 mutations in general had significant improvements in progression-free survival (PFS) and overall survival (OS).

Conclusions: In Chinese EOC patients, the distributions and risk factors associated with germline and somatic BRCA1/2 mutations were similar to those previously reported in international studies. Deleterious BRCA mutations in general were associated with improved survival outcomes in this cohort.

Recommendations for Advancing the Diagnosis and Management of Hereditary Breast and Ovarian Cancer in Brazil

PURPOSE

The objective of this review was to address the barriers limiting access to genetic cancer risk assessment and genetic testing for individuals with suspected hereditary breast and ovarian cancer (HBOC) through a review of the diagnosis and management steps of HBOC.

METHODS

A selected panel of Brazilian experts in fields related to HBOC was provided with a series of relevant questions to address before the multiday conference. During this conference, each narrative was discussed and edited by the entire group, through numerous drafts and rounds of discussion, until a consensus was achieved.

RESULTS

The authors propose specific and realistic recommendations for improving access to early diagnosis, risk management, and cancer care of HBOC specific to Brazil. Moreover, in creating these recommendations, the authors strived to address all the barriers and impediments mentioned in this article.

CONCLUSION

There is a great need to expand hereditary cancer testing and counseling in Brazil, and changing current policies is essential to accomplishing this goal. Increased knowledge and awareness, together with regulatory actions to increase access to this technology, have the potential to improve patient care and prevention and treatment efforts for patients with cancer across the country.

Germline Mutation in 1338 BRCA-Negative Chinese Hereditary Breast and/or Ovarian Cancer Patients: Clinical Testing with a Multigene Test Panel

Differences in the mutation spectrum across ethnicities suggest the importance of identifying genes in addition to common high penetrant genes to estimate the associated breast cancer risk in China. A total of 1338 high-risk breast cancer patients who tested negative for germline BRCA1, BRCA2, TP53, and PTEN mutations between 2007 and 2017 were selected from the Hong Kong Hereditary Breast Cancer Family Registry. Patient samples were subjected to next-generation DNA sequencing using a multigene panel (Color Genomics). All detected pathogenic variants were validated by bidirectional DNA sequencing. The sequencing data were coanalyzed by a bioinformatics pipeline developed in-house. Sixty-one pathogenic variants (4.6%) were identified in this cohort in 11 cancer predisposition genes. Most carriers (77.1%) had early onset of breast cancer (age <45 years), 32.8% had family members with breast cancer, and 11.5% had triple-negative breast cancer. The most common mutated genes were PALB2 (1.4%), RAD51D (0.8%), and ATM (0.8%). A total of 612 variants of unknown significance were identified in 494 patients, and 87.4% of the variants of unknown significance were missense mutations. Pathogenic variants in cancer predisposition genes beyond BRCA1, BRCA2, TP53, and PTEN were detected in an additional 4.6% of patients using the multigene panel. PALB2 (1.4%) and RAD51D (0.8%) were the most commonly mutated genes in patients who tested mutation negative by a four-gene panel.

Metachronous Contralateral Male Breast Cancer: Case Report and Literature Review

Male breast cancer (MBC) is rare and consequently understudied. Here we present the case of contralateral breast cancer in a male patient nearly a quarter century following his initial breast cancer diagnosis and treatment. The epidemiology, risk factors, diagnosis, characterization, treatment, and prognosis of male breast cancer are reviewed. MBC accounts for <1% of all breast cancer with an estimated incidence nearly 1.25 per 100,000 person years. Our patient tested positive for ATM mutation of undetermined significance. More commonly in males, a BRCA2 mutation confers a >1 in 15 lifetime risk of breast cancer and is present in >11% of MBC patients, while BRCA1 is present in an estimated <1.5% of MBC patients. The risk of contralateral breast cancer developing in a male with a unilateral lesion is much higher than for a primary male breast cancer in the general population. Men tend to be diagnosed at a later age and stage than females. Prognosis for male and female breast cancer is similar considering both age of patient and stage of the tumor at diagnosis, and similar treatment paradigms have resulted in similar outcomes. Although lumpectomy with radiation therapy may have the same prognosis as mastectomy, the standard of care for male breast cancer continues to be simple mastectomy with sentinel lymph node biopsy.

Oncological Safety of Lipofilling in Healthy BRCA Carriers After Bilateral Prophylactic Mastectomy: A Case Series

OBJECTIVE

The germline breast cancer gene (BRCA) mutation confers a lifetime high risk for breast cancer (BC) and bilateral prophylactic mastectomy is the procedure which allows the highest risk reduction rate. Among other techniques, lipofilling (LF) can be used for breast reconstruction of these patients. However, there are some oncological safety concerns on the subject. The purpose of this study was to assess the oncological risk of LF in BRCA healthy patients.

MATERIALS AND METHODS

A single institution case series was built including BRCA I/II mutated patients with no previous history of BC, who underwent bilateral prophylactic mastectomy followed by breast reconstruction with exclusive LF or combined with implants or latissimus dorsi flap. Data were collected regarding patient demographics, clinical information, reconstruction techniques used, and fat grafting details.

RESULTS

From September 1999 till November 2017, we identified 18 BRCA carriers with no history of BC who had undergone bilateral prophylactic mastectomy, followed by breast reconstruction with LF. A total of 36 LF procedures were performed following an implant or latissimus dorsi flap, or as an exclusive fat grafting breast reconstruction. The average number of LF sessions was 1.4 with a mean volume of 108.8cc per breast. Median follow-up was 33.0 months after mastectomy and 24.5 months after the last LF intervention; no patients were diagnosed with BC during follow-up.

CONCLUSION

Germline BRCA mutation is a high-risk plight for BC. However, despite the limited follow-up, no BC was detected.

Germline mutation in DNA-repair genes is associated with poor survival in BRCA1/2-negative breast cancer patients

BRCA1/2 genes are the most frequently germline mutated DNA‐repair genes, and the survival of BRCA1/2 carriers has been extensively explored in breast cancer. However, the prevalence of germline mutations in non‐BRCA1/2 DNA‐repair genes and the survival of carriers are largely unknown in a large cohort of unselected breast cancer patients. Germline mutations in 16 DNA‐repair genes were determined using a multigene panel in 7657 BRCA1/2‐negative breast cancer patients who were unselected for family history of cancer or age at diagnosis. Among the 7657 BRCA1/2‐negative breast cancer patients, 257 (3.4%) carried at least 1 pathogenic germline mutation in the 16 DNA‐repair genes. The prevalence of DNA‐repair gene mutations was significantly higher in familial breast cancers (5.2%, P = 0.002) and early‐onset breast cancers (diagnosed at and before the age of 40) (4.5%, P = 0.003) than that of sporadic breast cancers (2.9%) (diagnosed above age of 40), respectively. The DNA‐repair gene mutation carriers were significantly more likely to have a larger tumor (P = 0.04) and axillary lymph node metastasis (P = 0.03). Moreover, DNA‐repair gene mutation was an independent unfavorable factor for recurrence‐free survival (adjusted hazard ratio [HR] = 1.38, 95% CI: 1.00‐1.91, P = 0.05) and disease‐specific survival (adjusted HR=1.63, 95% CI: 1.04‐2.57, P = 0.03) in this cohort. Overall, 3.4% of BRCA1/2‐negative breast cancer patients carried germline mutations in the 16 DNA‐repair genes, and the DNA‐repair gene mutation carriers exhibited an aggressive phenotype and had poor survival compared with noncarriers.

Multi gene panel testing for hereditary breast cancer - is it ready to be used?

Breast cancer is one of the most common malignancies and the leading cause of death among women worldwide. About 20% of breast cancers are hereditary. Approximately 30% of the mutations have remained negative after testing BRCA1/2 even in families with a Mendelian inheritance pattern for breast cancer. Additional non-BRCA genes have been identified as predisposing for breast cancer. Multi gene panel testing tries to cover and explain the BRCA negative inherited breast cancer, improving efficiency, speed and costs of the breast cancer screening. We identified 23 studies reporting results from individuals who have undergone multi gene panel testing for hereditary breast cancer and noticed a prevalence of 1-12% of non-BRCA genes, but also a high level of variants of uncertain significance. A result with a high level of variants of uncertain significance is likely to be more costly than bring benefits, as well as increase the anxiety for patients. Regarding further development of multi gene panel testing, more research is required to establish both the optimal care of patients with cancer (specific treatments like PARP inhibitors) and the management of unaffected individuals (chemoprevention and/or prophylactic surgeries). Early detection in these patients as well as prophylactic measures will significantly increase the chance of survival. Therefore, multi gene panel testing is not yet ready to be used outside clear guidelines. In conclusion, studies on additional cohorts will be needed to better define the real prevalence, penetrance and the variants of these genes, as well as to describe clear evidence-based guidelines for these patients.

Evaluation of Cancer-Based Criteria for Use in Mainstream BRCA1 and BRCA2 Genetic Testing in Patients With Breast Cancer

IMPORTANCE

Increasing BRCA1 and BRCA2 (collectively termed herein as BRCA) gene testing is required to improve cancer management and prevent BRCA-related cancers.

OBJECTIVE

To evaluate mainstream genetic testing using cancer-based criteria in patients with cancer.

DESIGN, SETTING, AND PARTICIPANTS

A quality improvement study and cost-effectiveness analysis of different BRCA testing selection criteria and access procedures to evaluate feasibility, acceptability, and mutation detection performance was conducted at the Royal Marsden National Health Service Foundation Trust as part of the Mainstreaming Cancer Genetics (MCG) Programme. Participants included 1184 patients with cancer who were undergoing genetic testing between September 1, 2013, and February 28, 2017.

MAIN OUTCOMES AND MEASURES

Mutation rates, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios were the primary outcomes.

RESULTS

Of the 1184 patients (1158 women [97.8%]) meeting simple cancer-based criteria, 117 had a BRCA mutation (9.9%). The mutation rate was similar in retrospective United Kingdom (10.2% [235 of 2294]) and prospective Malaysian (9.7% [103 of 1061]) breast cancer studies. If traditional family history criteria had been used, more than 50% of the mutation-positive individuals would have been missed. Of the 117 mutation-positive individuals, 115 people (98.3%) attended their genetics appointment and cascade to relatives is underway in all appropriate families (85 of 85). Combining with the equivalent ovarian cancer study provides 5 simple cancer-based criteria for BRCA testing with a 10% mutation rate: (1) ovarian cancer; (2) breast cancer diagnosed when patients are 45 years or younger; (3) 2 primary breast cancers, both diagnosed when patients are 60 years or younger; (4) triple-negative breast cancer; and (5) male breast cancer. A sixth criterion-breast cancer plus a parent, sibling, or child with any of the other criteria-can be added to address family history. Criteria 1 through 5 are considered the MCG criteria, and criteria 1 through 6 are considered the MCGplus criteria. Testing using MCG or MCGplus criteria is cost-effective with cost-effectiveness ratios of $1330 per discounted QALYs and $1225 per discounted QALYs, respectively, and appears to lead to cancer and mortality reductions (MCG: 804 cancers, 161 deaths; MCGplus: 1020 cancers, 204 deaths per year over 50 years). Use of MCG or MCGplus criteria might allow detection of all BRCA mutations in patients with breast cancer in the United Kingdom through testing one-third of patients. Feedback questionnaires from 259 patients and 23 cancer team members (12 oncologists, 8 surgeons, and 3 nurse specialists) showed acceptability of the process with 100% of patients pleased they had genetic testing and 100% of cancer team members confident to approve patients for genetic testing. Use of MCGplus criteria also appeared to be time and resource efficient, requiring 95% fewer genetic consultations than the traditional process.

CONCLUSIONS AND RELEVANCE

This study suggests that mainstream testing using simple, cancer-based criteria might be able to efficiently deliver consistent, cost-effective, patient-centered BRCA testing.

Alternative splicing and ACMG-AMP-2015-based classification of PALB2 genetic variants: an ENIGMA report

BACKGROUND

PALB2 monoallelic loss-of-function germ-line variants confer a breast cancer risk comparable to the average BRCA2 pathogenic variant. Recommendations for risk reduction strategies in carriers are similar. Elaborating robust criteria to identify loss-of-function variants in PALB2-without incurring overprediction-is thus of paramount clinical relevance. Towards this aim, we have performed a comprehensive characterisation of alternative splicing in PALB2, analysing its relevance for the classification of truncating and splice site variants according to the 2015 American College of Medical Genetics and Genomics-Association for Molecular Pathology guidelines.

METHODS

Alternative splicing was characterised in RNAs extracted from blood, breast and fimbriae/ovary-related human specimens (n=112). RNAseq, RT-PCR/CE and CloneSeq experiments were performed by five contributing laboratories. Centralised revision/curation was performed to assure high-quality annotations. Additional splicing analyses were performed in PALB2 c.212-1G>A, c.1684+1G>A, c.2748+2T>G, c.3113+5G>A, c.3350+1G>A, c.3350+4A>C and c.3350+5G>A carriers. The impact of the findings on PVS1 status was evaluated for truncating and splice site variant.

RESULTS

We identified 88 naturally occurring alternative splicing events (81 newly described), including 4 in-frame events predicted relevant to evaluate PVS1 status of splice site variants. We did not identify tissue-specific alternate gene transcripts in breast or ovarian-related samples, supporting the clinical relevance of blood-based splicing studies.

CONCLUSIONS

PVS1 is not necessarily warranted for splice site variants targeting four PALB2 acceptor sites (exons 2, 5, 7 and 10). As a result, rare variants at these splice sites cannot be assumed pathogenic/likely pathogenic without further evidences. Our study puts a warning in up to five PALB2 genetic variants that are currently reported as pathogenic/likely pathogenic in ClinVar.

Practice Implications of Expanded Genetic Testing in Oncology

Genetic test use in oncology is growing, yet providers' experiences with evolving testing norms and their implications for patient care remain under-explored. In interviews with oncologists and cancer genetics professionals, 22 key informants described the increasing importance of germline results for therapeutic decision-making, preference for ordering tests directly rather than referring, and rapid adoption of cancer gene panels for testing. Implications for informed consent, result interpretation, and patient management were identified. These results suggest concerns raised by the transition of genetic test delivery from cancer genetics professionals to oncologists that must be addressed in practice guidelines and provider training.

BRCA Challenge: BRCA Exchange as a global resource for variants in BRCA1 and BRCA2

The BRCA Challenge is a long-term data-sharing project initiated within the Global Alliance for Genomics and Health (GA4GH) to aggregate BRCA1 and BRCA2 data to support highly collaborative research activities. Its goal is to generate an informed and current understanding of the impact of genetic variation on cancer risk across the iconic cancer predisposition genes, BRCA1 and BRCA2. Initially, reported variants in BRCA1 and BRCA2 available from public databases were integrated into a single, newly created site, www.brcaexchange.org. The purpose of the BRCA Exchange is to provide the community with a reliable and easily accessible record of variants interpreted for a high-penetrance phenotype. More than 20,000 variants have been aggregated, three times the number found in the next-largest public database at the project’s outset, of which approximately 7,250 have expert classifications. The data set is based on shared information from existing clinical databases—Breast Cancer Information Core (BIC), ClinVar, and the Leiden Open Variation Database (LOVD)—as well as population databases, all linked to a single point of access. The BRCA Challenge has brought together the existing international Evidence-based Network for the Interpretation of Germline Mutant Alleles (ENIGMA) consortium expert panel, along with expert clinicians, diagnosticians, researchers, and database providers, all with a common goal of advancing our understanding of BRCA1 and BRCA2 variation. Ongoing work includes direct contact with national centers with access to BRCA1 and BRCA2 diagnostic data to encourage data sharing, development of methods suitable for extraction of genetic variation at the level of individual laboratory reports, and engagement with participant communities to enable a more comprehensive understanding of the clinical significance of genetic variation in BRCA1 and BRCA2.

The goal of this study and paper has been to develop an international resource to generate an informed and current understanding of the impact of genetic variation on cancer risk across the cancer predisposition genes, BRCA1 and BRCA2. Reported variants in BRCA1 and BRCA2 available from public databases were integrated into a single, newly created site, www.brcaexchange.org, to provide a reliable and easily accessible record of variants interpreted for a high-penetrance phenotype.

A narrative overview of the patients' outcomes after multigene cancer panel testing, and a thorough evaluation of its implications for genetic counselling

Massively parallel sequencing is being implemented in clinical practice through the use of multigene panel testing, whole exome sequencing and whole genome sequencing. In this manuscript we explore how the use of massively parallel sequencing, and in particular multigene cancer panel testing, is potentially changing the process of genetic counselling and how patients cope with pre-test genetic counselling and results. We found that the main challenges are around uncertainty, hopes and expectations and the amount and complexity of information that needs to be discussed. This may impact the process of genetic counselling, although genetic counsellors can still use their core skills and enhance some of them in order to evolve and meet patients' needs in the genomics era. Available data suggests that patients can cope with multigene cancer panels although more research is needed to fully understand the psychosocial implications of multigene cancer panels for patients, especially for those who have variants of unknown significance or moderate penetrance variants. Research is also needed to explore and develop communication models that maximize patients' understanding and empower them to make informed decisions.

[The French Genetic and Cancer Consortium guidelines for multigene panel analysis in hereditary breast and ovarian cancer predisposition]

INTRODUCTION

Next generation sequencing allows the simultaneous analysis of large panel of genes for families or individuals with a strong suspicion of hereditary breast and/or ovarian cancer (HBOC). Because of lack of guidelines, several panels of genes potentially involved in HBOC were designed, with large disparities not only in their composition but also in medical care offered to mutation carriers. Then, homogenization in practices is needed.

METHODS

The French Genetic and Cancer Group (GGC) - Unicancer conducted an exhaustive bibliographic work on 18 genes of interest. Only publications with unbiased risk estimates were retained.

RESULTS

The expertise of each 18 genes was based on clinical utility criteria, i.e. a relative risk of cancer of 4 and more, available medical tools for screening and prevention of mutation carriers, and pre-symptomatic genetic tests for relatives. Finally, 13 genes were selected to be included in a HBOC diagnosis gene panel: BRCA1, BRCA2, PALB2, TP53, CDH1, PTEN, RAD51C, RAD51D, MLH1, MSH2, MSH6, PMS2, EPCAM. The reasons for excluding NBN, RAD51B, CHEK2, STK11, ATM, BARD1, BRIP1 from the HBOC diagnosis panel are presented. Screening, prevention and genetic counselling guidelines were detailed for each of the 18 genes.

DISCUSSION

Due to the rapid increase in knowledge, the GGC has planned a yearly update of the bibliography to take into account new findings. Furthermore, genetic-epidemiological studies are being initiated to better estimate the cancer risk associated with genes which are not yet included in the HBOC diagnosis panel.

A Clinical Decision Support Tool to Predict Cancer Risk for Commonly Tested Cancer-Related Germline Mutations

The rapid drop in the cost of DNA sequencing led to the availability of multi-gene panels, which test 25 or more cancer susceptibility genes for a low cost. Clinicians and genetic counselors need a tool to interpret results, understand risk of various cancers, and advise on a management strategy. This is challenging as there are multiple studies regarding each gene, and it is not possible for clinicians and genetic counselors to be aware of all publications, nor to appreciate the relative accuracy and importance of each. Through an extensive literature review, we have identified reliable studies and derived estimates of absolute risk. We have also developed a systematic mechanism and informatics tools for (1) data curation, (2) the evaluation of quality of studies, and (3) the statistical analysis necessary to obtain risk. We produced the risk prediction clinical decision support tool ASK2ME (All Syndromes Known to Man Evaluator). It provides absolute cancer risk predictions for various hereditary cancer susceptibility genes. These predictions are specific to patients' gene carrier status, age, and history of relevant prophylactic surgery. By allowing clinicians to enter patient information and receive patient-specific cancer risks, this tool aims to have a significant impact on the quality of precision cancer prevention and disease management activities relying on panel testing. It is important to note that this tool is dynamic and constantly being updated, and currently, some of its limitations include (1) for many gene-cancer associations risk estimates are based on one study rather than meta-analysis, (2) strong assumptions on prior cancers, (3) lack of uncertainty measures, and (4) risk estimates for a growing set of gene-cancer associations which are not always variant specific. All of these concerns are being addressed on an ongoing basis, aiming to make the tool even more accurate.

Sputum Detection of Predisposing Genetic Mutations in Women with Pulmonary Nontuberculous Mycobacterial Disease

Nontuberculous mycobacterial lung disease (NTM), including Mycobacterium avium complex (MAC), is a growing health problem in North America and worldwide. Little is known about the molecular alterations occurring in the tissue microenvironment during NTM pathogenesis. Utilizing next generation sequencing, we sequenced sputum and matched lymphocyte DNA in 15 MAC patients for a panel of 19 genes known to harbor cancer susceptibility associated mutations. Thirteen of 15 NTM subjects had a diagnosis of breast cancer (BCa) before or after NTM infection. Thirty three percent (4/12) of these NTM-BCa cases exhibited at least 3 somatic mutations in sputa compared to matched lymphocytes. Twenty four somatic mutations were detected with at least one mutation in ATM, ERBB2, BARD1, BRCA1, BRCA2, AR, TP53, PALB2, CASP8, BRIP1, NBN and TGFB1 genes. All four NTM-BCa patients harboring somatic mutations also exhibited 15 germ line BRCA1 and BRCA2 mutations. The two NTM subjects without BCa exhibited twenty somatic mutations spanning BRCA1, BRCA1, BARD1, BRIP1, CHEK2, ERBB2, TP53, ATM, PALB2, TGFB1 and 3 germ line mutations in BRCA1 and BRCA2 genes. A single copy loss of STK11 and AR gene was noted in NTM-BCa subjects. Periodic screening of sputa may aid to develop risk assessment biomarkers for neoplastic diseases in NTM patients.

Discovery of mutations in homologous recombination genes in African-American women with breast cancer

African-American women are more likely to develop aggressive breast cancer at younger ages and experience poorer cancer prognoses than non-Hispanic Caucasians. Deficiency in repair of DNA by homologous recombination (HR) is associated with cancer development, suggesting that mutations in genes that affect this process may cause breast cancer. Inherited pathogenic mutations have been identified in genes involved in repairing DNA damage, but few studies have focused on African-Americans. We screened for germline mutations in seven HR repair pathway genes in DNA of 181 African-American women with breast cancer, evaluated the potential effects of identified missense variants using in silico prediction software, and functionally characterized a set of missense variants by yeast two-hybrid assays. We identified five likely-damaging variants, including two PALB2 truncating variants (Q151X and W1038X) and three novel missense variants (RAD51C C135R, and XRCC3 L297P and V337E) that abolish protein-protein interactions in yeast two-hybrid assays. Our results add to evidence that HR gene mutations account for a proportion of the genetic risk for developing breast cancer in African-Americans. Identifying additional mutations that diminish HR may provide a tool for better assessing breast cancer risk and improving approaches for targeted treatment.

Germline breast cancer susceptibility gene mutations and breast cancer outcomes

Background

It is unclear whether germline breast cancer susceptibility gene mutations affect breast cancer related outcomes. We wanted to evaluate mutation patterns in 20 breast cancer susceptibility genes and correlate the mutations with clinical characteristics to determine the effects of these germline mutations on breast cancer prognosis.

Methods

The study cohort included 480 ethnic Chinese individuals in Taiwan with at least one of the six clinical risk factors for hereditary breast cancer: family history of breast or ovarian cancer, young age of onset for breast cancer, bilateral breast cancer, triple negative breast cancer, both breast and ovarian cancer, and male breast cancer. PCR-enriched amplicon-sequencing on a next generation sequencing platform was used to determine the germline DNA sequences of all exons and exon-flanking regions of the 20 genes. Protein-truncating variants were identified as pathogenic.

Results

We detected a 13.5% carrier rate of pathogenic germline mutations, with BRCA2 being the most prevalent and the non-BRCA genes accounting for 38.5% of the mutation carriers. BRCA mutation carriers were more likely to be diagnosed of breast cancer with lymph node involvement (66.7% vs 42.6%; P = 0.011), and had significantly worse breast cancer specific outcomes. The 5-year disease-free survival was 73.3% for BRCA mutation carriers and 91.1% for non-carriers (hazard ratio for recurrence or death 2.42, 95% CI 1.29–4.53; P = 0.013). After adjusting for clinical prognostic factors, BRCA mutation remained an independent poor prognostic factor for cancer recurrence or death (adjusted hazard ratio 3.04, 95% CI 1.40–6.58; P = 0.005). Non-BRCA gene mutation carriers did not exhibit any significant difference in cancer characteristics or outcomes compared to those without detected mutations. Among the risk factors for hereditary breast cancer, the odds of detecting a germline mutation increased significantly with having bilateral breast cancer (adjusted odds ratio 3.27, 95% CI 1.64–6.51; P = 0.0008) or having more than one risk factor (odds ratio 2.07, 95% CI 1.22–3.51; P = 0.007).

Conclusions

Without prior knowledge of the mutation status, BRCA mutation carriers had more advanced breast cancer on initial diagnosis and worse cancer-related outcomes. Optimal approach to breast cancer treatment for BRCA mutation carriers warrants further investigation.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4229-5) contains supplementary material, which is available to authorized users.

Hereditary Breast and Ovarian Cancer Syndrome: Moving Beyond BRCA1 and BRCA2

The recent implementation of next generation sequencing and multigene platforms has expanded the spectrum of hereditary breast and ovarian cancer syndrome, beyond the traditional genes BRCA1 and BRCA2. A large number of other moderate penetrance genes have now been uncovered, which also play critical roles in repairing double stranded DNA breaks through the homologous recombination pathway. This review discusses the landmark discoveries of BRCA1 and BRCA2, the homologous repair pathway and new genes discovered in hereditary breast and ovarian cancer syndrome, as well as their clinicopathologic significance and implications for genetic testing. It also highlights the new role of PARP inhibitors in the context of synthetic lethality and prophylactic surgical options.

The Perils of Single-Site Genetic Testing for Hereditary Cancer Syndromes in the Era of Next-Generation Sequencing

A challenge in counseling patients with a family history suggesting a hereditary cancer syndrome is deciding which genetic tests or panels to order. In this article, we discuss the identification of multiple familial mutations through genetic counseling and panel testing. For patients meeting National Comprehensive Cancer Network criteria for clinical genetic testing, providers should consider expanded panels to provide a more complete assessment of one's genetic risk. The continued use of expanded panel testing in the clinical setting will help inform optimal management of cancer patients, as well as the management of their unaffected family members. The mutation discovered in this case was in the ATM gene. The clinical significance of the mutation, potential therapeutic targets, and proper clinical management are discussed.

KEY POINTS

With single-site genetic testing, there is the potential to miss hereditary genetic syndromes that can be managed clinically.Between 4% and 6% of hereditary breast and ovarian cancer syndromes are caused by genes other than BRCA1 and BRCA2.ATM is a DNA mismatch repair gene associated with double-stranded DNA break repair and cell cycle checkpoint arrest.The risk of developing female breast cancer by age 50 and by age 80 in ATM heterozygotes is 9% and 17%-52%, respectively.

Gene-panel testing of breast and ovarian cancer patients identifies a recurrent RAD51C duplication

Gene-panel sequencing allows comprehensive analysis of multiple genes simultaneously and is now routinely used in clinical mutation testing of high-risk breast and ovarian cancer patients. However, only BRCA1 and BRCA2 are often analyzed also for large genomic changes. Here, we have analyzed 10 clinically relevant susceptibility genes in 95 breast or ovarian cancer patients with gene-panel sequencing including also copy number variants (CNV) analysis for genomic changes. We identified 12 different pathogenic BRCA1, BRCA2, TP53, PTEN, CHEK2, or RAD51C mutations in 18 of 95 patients (19%). BRCA1/2 mutations were observed in 8 patients (8.4%) and CHEK2 protein-truncating mutations in 7 patients (7.4%). In addition, we identified a novel duplication encompassing most of the RAD51C gene. We further genotyped the duplication in breast or ovarian cancer families (n = 1149), in unselected breast (n = 1729) and ovarian cancer cohorts (n = 553), and in population controls (n = 1273). Seven additional duplication carries were observed among cases but none among controls. The duplication associated with ovarian cancer risk (3/590 of all ovarian cancer patients, 0.5%, P = .032 compared with controls) and was found to represent a large fraction of all identified RAD51C mutations in the Finnish population. Our data emphasizes the importance of comprehensive mutation analysis including CNV detection in all the relevant genes.

Non-BRCA1/2 Breast Cancer Susceptibility Genes: A New Frontier with Clinical Consequences for Plastic Surgeons

Twenty percent of breast cancer cases may be related to a genetic mutation conferring an increased risk of malignancy. The most common and prominent breast cancer susceptibility genes are BRCA1 and BRCA2, found in nearly 40% of such cases. However, continued interest and investigation of cancer genetics has led to the identification of a myriad of different breast cancer susceptibility genes. Additional genes, each with unique significance and associated characteristics, continue to be recognized. Concurrently, advanced genetic testing, while still controversial, has become more accessible and cost-effective. As oncologic and reconstructive advances continue to be made in prophylactic breast reconstructive surgery, patients may present to plastic surgeons with an increasingly more diverse array of genetic diagnoses to discuss breast reconstruction. It is therefore imperative that plastic surgeons be familiar with these breast cancer susceptibility genes and their clinical implications. We, therefore, aim to review the most common non-BRCA1/2 breast cancer susceptibility genetic mutations in an effort to assist plastic surgeons in counseling and managing this unique patient population. Included in this review are syndromic breast cancer susceptibility genes such as TP53, PTEN, CDH1, and STK11, among others. Nonsyndromic breast cancer susceptibility genes herein reviewed include PALB2, CHEK2, and ataxia telangiectasia mutated gene. With this knowledge, plastic surgeons can play a central role in the diagnosis and comprehensive treatment, including successful breast reconstruction, of all patients carrying genetic mutations conferring increased risk for breast malignancies.

The Changing Landscape of Genetic Testing for Inherited Breast Cancer Predisposition

OPINION STATEMENT

The advent of multiple-gene germline panel testing has led to significant advances in hereditary breast and ovarian cancer risk assessment. These include guideline-specific cancer risk management recommendations for patients and their families, such as screening with breast magnetic resonance imaging and risk-reducing surgeries, which have the potential to reduce substantially the morbidity and mortality associated with a hereditary cancer predisposition. However, controversy remains about the clinical validity and actionability of genetic testing in a broader patient population. We discuss events leading to the wider availability of commercialized multiple-gene germline panel testing, the recent data that support using this powerful tool to improve cancer risk assessment and reduction strategies, and remaining challenges to clinical optimization of this new genetic technology.

Genetic Testing: Challenges and Changes in Testing for Hereditary Cancer Syndromes

BACKGROUND

The practice of genetic testing for hereditary cancer syndromes has changed dramatically in recent years, and patients often approach oncology nurses requesting information about genetic testing.
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OBJECTIVES

This article aims to explore changes in cancer genetics, the role of genetics professionals in providing comprehensive genetic care, and the implications of these new developments in genetics for oncology nurses.
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METHODS

A literature review was conducted and focused on articles about the updating of genetic tests with panel testing, insurance changes, alternative genetic counseling strategies, and direct-to-consumer genetic testing.
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FINDINGS

Oncology nurses play an important role in identifying and referring patients, including those who have tested negative for hereditary susceptibility genes, to genetics professionals. Genetics professionals can assist with insurance issues, interpretation of test results, clarification when a variant of unknown clinical significance is detected, and recommendations for care based on personal and family history and testing results. Oncology nurses can assist families with understanding the limitations of direct-to-consumer genetic testing.

DNA repair-related functional assays for the classification of BRCA1 and BRCA2 variants: a critical review and needs assessment

Mutation of BRCA1 and BRCA2 is the most common cause of inherited breast and ovarian cancer. Genetic screens to detect carriers of variants can aid in cancer prevention by identifying individuals with a greater cancer risk and can potentially be used to predict the responsiveness of tumours to therapy. Frequently, classification cannot be performed based on traditional approaches such as segregation analyses, including for many missense variants, which are therefore referred to as variants of uncertain significance (VUS). Functional assays provide an important alternative for classification of BRCA1 and BRCA2 VUS. As reviewed here, both of these tumour suppressors promote the maintenance of genome stability via homologous recombination. Thus, related assays may be particularly relevant to cancer risk. Progress in implementing functional assays to assess missense variants of BRCA1 and BRCA2 is considered here, along with current limitations and the path to more impactful assay systems. While functional assays have been developed to independently evaluate BRCA1 and BRCA2 VUS, high-throughput assays with sufficient sensitivity to characterise the large number of identified variants are lacking. Additionally, because of relatively low conservation of certain domains of BRCA1, and of BRCA2, between humans and rodents, heterologous expression in rodent cells may have limited reliability or capacity to assess variants present throughout either protein. Moving forward, it will be important to perform assays in human cell lines with relevance to particular tumour types, and to strengthen risk predictions based on multifactorial statistical analyses that also include available data on cosegregation and tumour pathology.

Identification, genetic testing, and management of hereditary melanoma

Several distinct melanoma syndromes have been defined, and genetic tests are available for the associated causative genes. Guidelines for melanoma genetic testing have been published as an informal "rule of twos and threes," but these guidelines apply to CDKN2A testing and are not intended for the more recently described non-CDKN2A melanoma syndromes. In order to develop an approach for the full spectrum of hereditary melanoma patients, we have separated melanoma syndromes into two types: "melanoma dominant" and "melanoma subordinate." Syndromes in which melanoma is a predominant cancer type are considered melanoma dominant, although other cancers, such as mesothelioma or pancreatic cancers, may also be observed. These syndromes are associated with defects in CDKN2A, CDK4, BAP1, MITF, and POT1. Melanoma-subordinate syndromes have an increased but lower risk of melanoma than that of other cancer(s) seen in the syndrome, such as breast and ovarian cancer or Cowden syndrome. Many of these melanoma-subordinate syndromes are associated with well-established predisposition genes (e.g., BRCA1/2, PTEN). It is likely that these predisposition genes are responsible for the increased susceptibility to melanoma as well but with lower penetrance than that observed for the dominant cancer(s) in those syndromes. In this review, we describe our extension of the "rule of twos and threes" for melanoma genetic testing. This algorithm incorporates an understanding of the spectrum of cancers and genes seen in association with melanoma to create a more comprehensive and tailored approach to genetic testing.