BRCA genetic testing of individuals from families with low prevalence of cancer: experiences of carriers and implications for population screening

Factors associated with adherence to BRCA1/2 mutation testing after oncogenetic counseling in long-surviving patients with a previous diagnosis of breast or ovarian cancer

BRCA1/2 mutations account for 5 to 10% of breast and 15% of ovarian cancers. Various guidelines on BRCA1/2 genetic counseling and testing have been issued, and the criteria have evolved over the years. Oncogenetic counseling aims to inform patients about the possibility and implications of undergoing predictive testing and risk management programs. We analyzed a cohort of 50 subjects with a previous personal history of breast or ovarian cancer who had not been tested for BRCA1/2 mutations at the time of diagnosis but were found eligible according to the most recent guidelines. All patients were offered pre-test oncogenetic counseling and BRCA1/2 genetic testing. The mean time from cancer diagnosis to genetic counseling was over 10 years. We analyzed socio-demographic and psychological parameters associated with the decision to undergo BRCA1/2 genetic testing or the reasons behind the withdrawal. Thirty-nine patients underwent BRCA1/2 genetic testing. Patients who accept the genetic test communicate more easily with family members than those who refuse. Factors associated with test refusal are having a long-term partner and having a negative perception of life. There is a trend, although not statistically significant, toward younger age at cancer diagnosis, more likely to participate in cancer screening programs (71.8% vs. 45.5%), and more likely to have daughters (63.3% vs. 37.5%) in the group that accepted the test. The offer of BRCA testing was well accepted by our study population, despite the many years since the cancer diagnosis. With the perspective of further broadening the access criteria to genetic testing, it is important to understand how to best approach pre-test counseling in long-surviving patients with a previous diagnosis of cancer.

Unselected Population Genetic Testing for Personalised Ovarian Cancer Risk Prediction: A Qualitative Study Using Semi-Structured Interviews

Unselected population-based personalised ovarian cancer (OC) risk assessments combining genetic, epidemiological and hormonal data have not previously been undertaken. We aimed to understand the attitudes, experiences and impact on the emotional well-being of women from the general population who underwent unselected population genetic testing (PGT) for personalised OC risk prediction and who received low-risk (<5% lifetime risk) results. This qualitative study was set within recruitment to a pilot PGT study using an OC risk tool and telephone helpline. OC-unaffected women ≥ 18 years and with no prior OC gene testing were ascertained through primary care in London. In-depth, semi-structured and 1:1 interviews were conducted until informational saturation was reached following nine interviews. Six interconnected themes emerged: health beliefs; decision making; factors influencing acceptability; effect on well-being; results communication; satisfaction. Satisfaction with testing was high and none expressed regret. All felt the telephone helpline was helpful and should remain optional. Delivery of low-risk results reduced anxiety. However, care must be taken to emphasise that low risk does not equal no risk. The main facilitators were ease of testing, learning about children’s risk and a desire to prevent disease. Barriers included change in family dynamics, insurance, stigmatisation and personality traits associated with stress/worry. PGT for personalised OC risk prediction in women in the general population had high acceptability/satisfaction and reduced anxiety in low-risk individuals. Facilitators/barriers observed were similar to those reported with genetic testing from high-risk cancer clinics and unselected PGT in the Jewish population.

Psychosocial outcome and health behaviour intent of breast cancer patients with BRCA1/2 and PALB2 pathogenic variants unselected by a priori risk

There is an increasing number of cancer patients undertaking treatment-focused genetic testing despite not having a strong family history or high a priori risk of being carriers because of the decreasing cost of genetic testing and development of new therapies. There are limited studies on the psychosocial outcome of a positive result among breast cancer patients who are at low a priori risk, particularly in women of Asian descent. Breast cancer patients enrolled under the Malaysian Breast Cancer Genetic Study between October 2002 and February 2018 were tested for BRCA1, BRCA2 and PALB2 genes. All 104 carriers identified were invited by a research genetic counsellor for result disclosure. Of the 104 carriers, 64% (N = 66) had low a priori risk as determined by PENN II scores. Psychosocial, risk perception and health behaviour measures survey were conducted at baseline (pre-result disclosure), and at two to six weeks after result disclosure. At baseline, younger carriers with high a priori risk had higher Cancer Worry Scale scores than those with low a priori risk but all scores were within acceptable range. Around 75% and 55% of high a priori risk carriers as well as 80% and 67% of low a priori risk carriers had problems in the "living with cancer" and "children" psychosocial domains respectively. All carriers regardless of their a priori risk demonstrated an improved risk perception that also positively influenced their intent to undergo risk management procedures. This study has shown that with sufficient counselling and support, low a priori risk carriers are able to cope psychologically, have improved perceived risk and increased intent for positive health behaviour despite having less anticipation from a family history prior to knowing their germline carrier status.

Psychological Distress and Quality of Life in Participants Undergoing Genetic Testing for Arrhythmogenic Right Ventricular Cardiomyopathy Caused by TMEM43 p.S358L: Is It Time to Offer Population-Based Genetic Screening?

PURPOSE

We have identified 27 families in Newfoundland and Labrador (NL) with the founder variant TMEM43 p.S358L responsible for 1 form of arrhythmogenic right ventricular cardiomyopathy. Current screening guidelines rely solely on cascade genetic screening, which may result in unrecognized, high-risk carriers who would benefit from preemptive implantable cardioverter-defibrillator therapy. This pilot study explored the acceptability among subjects to TMEM43 p.S358L population-based genetic screening (PBGS) in this Canadian province.

METHODS

A prospective cohort study assessed attitudes, psychological distress, and health-related quality of life (QOL) in unselected individuals who underwent genetic screening for the TMEM43 p.S358L variant. Participants (n = 73) were recruited via advertisements and completed 2 surveys at baseline, 6 months, and 1 year which measured health-related QOL (SF-36v2) and psychological distress (Impact of Events Scale).

RESULTS

No variant-positive carriers were identified. Of those screened through a telephone questionnaire, >95% felt positive about population-genetic screening for TMEM43 p.S358L, though 68% reported some degree of anxiety after seeing the advertisement. There were no significant changes in health-related QOL or psychological distress scores over the study period.

CONCLUSION

Despite some initial anxiety, we show support for PBGS among research subjects who screened negative for the TMEM43 p.S358L variant in NL. These findings have implications for future PBGS programs in the province.

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.

"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.

Hereditary Breast and Ovarian Cancer in Families from Southern Italy (Sicily)-Prevalence and Geographic Distribution of Pathogenic Variants in BRCA1/2 Genes

Recent advances in the detection of germline pathogenic variants (PVs) in BRCA1/2 genes have allowed a deeper understanding of the BRCA-related cancer risk. Several studies showed a significant heterogeneity in the prevalence of PVs across different populations. Because little is known about this in the Sicilian population, our study was aimed at investigating the prevalence and geographic distribution of inherited BRCA1/2 PVs in families from this specific geographical area of Southern Italy. We retrospectively collected and analyzed all clinical information of 1346 hereditary breast and/or ovarian cancer patients genetically tested for germline BRCA1/2 PVs at University Hospital Policlinico "P. Giaccone" of Palermo from January 1999 to October 2019. Thirty PVs were more frequently observed in the Sicilian population but only some of these showed a specific territorial prevalence, unlike other Italian and European regions. This difference could be attributed to the genetic heterogeneity of the Sicilian people and its historical background. Therefore hereditary breast and ovarian cancers could be predominantly due to BRCA1/2 PVs different from those usually detected in other geographical areas of Italy and Europe. Our investigation led us to hypothesize that a higher prevalence of some germline BRCA PVs in Sicily could be a population-specific genetic feature of BRCA-positive carriers.

Understanding Factors Associated with Uptake of BRCA1/2 Genetic Testing among Orthodox Jewish Women in the USA Using a Mixed-Methods Approach

BACKGROUND/AIMS

Ashkenazi Jews have a 1:40 prevalence of BRCA1/2 mutations. Orthodox Jews are an understudied population with unique cultural and religious factors that may influence BRCA1/2 genetic testing uptake.

METHODS

Using a mixed-methods approach, we conducted a cross-sectional survey and focus groups among Orthodox Jewish women in New York/New Jersey to explore factors affecting decision-making about BRCA1/2 genetic testing.

RESULTS

Among 321 evaluable survey participants, the median age was 47 years (range, 25-82); 56% were Modern Orthodox and 44% Yeshivish/Chassidish/other; 84% were married; 7% had a personal history of breast or ovarian cancer. Nearly 20% of the women had undergone BRCA1/2genetic testing. Predictors of genetic testing uptake included being Modern Orthodox (odds ratio [OR] = 2.31), married (OR = 3.49), and having a personal or family history of breast or ovarian cancer (OR = 9.74). Focus group participants (n = 31) confirmed the importance of rabbinic consultation in medical decision-making and revealed that stigma was a prominent factor in decisions about BRCA1/2 testing due to its potential impact on marriageability.

CONCLUSION

In order to increase the uptake of BRCA1/2 genetic testing among the Orthodox Jewish population, it is crucial to understand religious and cultural factors, such as stigma and effect on marriageability, and engage religious leaders in raising awareness within the community.

Population Based Testing for Primary Prevention: A Systematic Review

The current clinical model for genetic testing is based on clinical-criteria/family-history (FH) and a pre-defined mutation probability threshold. It requires people to develop cancer before identifying unaffected individuals in the family to target prevention. This process is inefficient, resource intensive and misses >50% of individuals or mutation carriers at risk. Population genetic-testing can overcome these limitations. It is technically feasible to test populations on a large scale; genetic-testing costs are falling and acceptability and awareness are rising. MEDLINE, EMBASE, Pubmed, CINAHL and PsychINFO databases were searched using free-text and MeSH terms; retrieved reference lists of publications were screened; additionally, web-based platforms, Google, and clinical-trial registries were searched. Quality of studies was evaluated using appropriate check-lists. A number of studies have evaluated population-based BRCA-testing in the Jewish population. This has been found to be acceptable, feasible, clinically-effective, safe, associated with high satisfaction rates and extremely cost-effective. Data support change in guidelines for population-based BRCA-testing in the Jewish population. Population panel testing for BRCA1/BRCA2/RAD51C/RAD51D/BRIP1/PALB2 gene mutations is the most cost-effective genetic-testing strategy in general-population women and can prevent thousands more breast and ovarian cancers than current clinical-criteria based approaches. A few ongoing studies are evaluating population-based genetic-testing for multiple cancer susceptibility genes in the general population but more implementation studies are needed. A future population-testing programme could also target other chronic diseases.

Hereditary cancer screening: Case reports and review of literature on ten Ashkenazi Jewish founder mutations

BACKGROUND

Historically, three founder mutations in the BRCA1/2 (OMIM 113705; OMIM 600185) genes have been the focus of cancer risks within the Ashkenazi Jewish (AJ) population. However, there are several additional mutations associated with increased susceptibility to cancer in individuals of AJ ancestry.

METHODS

We report three patients who exemplify the need to keep these additional founder mutations in mind when pursuing hereditary cancer genetic testing of individuals in this population. All gene sequences in this paper were aligned to reference sequences based on human genome build GRCh37/UCSC hg19.

RESULTS

review of the literature discusses that the combined risk is 12.36%-20.83% forhaving 1 of the 10 hereditary cancer AJ founder mutations in the BRCA1, BRCA2, CHEK2 (OMIM 604373), APC (OMIM 611731), MSH2 (OMIM 609309), MSH6 (OMIM 600678), and GREM1 (OMIM 603054) genes for individuals of AJ ancestry.

CONCLUSION

We recommend testing for all 10 of these AJ founder cancer susceptibility mutations for individuals within this population as standard screening in order to ensure appropriate cancer risk management and cascade testing.

Psychological outcomes and surgical decisions after genetic testing in women newly diagnosed with breast cancer with and without a family history

In patients with early breast cancer, personal and tumour characteristics other than family history are increasingly used to prompt genetic testing to guide women's cancer management (treatment-focused genetic testing, 'TFGT'). Women without a known strong family history of breast and/or ovarian may be more vulnerable to psychological sequelae arising from TFGT. We compared the impact of TFGT in women with (FH+) and without (FH-) a strong family history on psychological adjustment and surgical decisions. Women aged <50 years with high-risk features were offered TFGT before definitive breast cancer surgery and completed self-report questionnaires at four time points over 12 months. All 128 women opted for TFGT. TFGT identified 18 carriers of a disease-causing variant (50.0% FH+) and 110 non-carriers (59.1% FH+). There were no differences based on family history in bilateral mastectomy (BM) uptake, p = .190, or uptake of risk-reducing bilateral salpingo-oophorectomy (RRBSO), p = .093. FH- women had lower decreases in anxiety a year after diagnosis, p = .011, and regret regarding their decision whether to undergo BM, p = .022, or RRBSO, p = .016 than FH + women. FH- carriers reported significantly higher regret regarding their TFGT choice (p = .024) and test-related distress (p = .012) than FH + carriers, but this regret/distress could not be attributed to a concern regarding a possible worse prognosis. These findings indicate that FH- women may require additional counselling to facilitate informed decisions. Carriers without a family history may require additional follow-up counselling to facilitate psychological adjustment to their positive variant results, extra support in making surgical decisions, and counselling about how best to communicate results to family members.

When knowledge of a heritable gene mutation comes out of the blue: treatment-focused genetic testing in women newly diagnosed with breast cancer

Selection of women for treatment-focused genetic testing (TFGT) following a new diagnosis of breast cancer is changing. Increasingly a patient's age and tumour characteristics rather than only their family history are driving access to TFGT, but little is known about the impact of receiving carrier-positive results in individuals with no family history of cancer. This study assesses the role of knowledge of a family history of cancer on psychosocial adjustment to TFGT in both women with and without mutation carrier-positive results. In-depth semistructured interviews were conducted with 20 women who had undergone TFGT, and who had been purposively sampled to represent women both family history and carrier status, and subjected to a rigorous qualitative analysis. It was found that mutation carriers without a family history reported difficulties in making surgical decisions quickly, while in carriers with a family history, a decision regarding surgery, electing for bilateral mastectomy (BM), had often already been made before receipt of their result. Long-term adjustment to a mutation-positive result was hindered by a sense of isolation not only by those without a family history but also those with a family history who lacked an affected relative with whom they could identify. Women with a family history who had no mutation identified and who had not elected BM reported a lack of closure following TFGT. These findings indicate support deficits hindering adjustment to positive TFGT results for women with and without a family history, particularly in regard to immediate decision-making about risk-reducing surgery.

Genetic testing of children for adult-onset conditions: opinions of the British adult population and implications for clinical practice

This study set out to explore the attitudes of a representative sample of the British public towards genetic testing in children to predict disease in the future. We sought opinions about genetic testing for adult-onset conditions for which no prevention/treatment is available during childhood, and about genetic ‘carrier' status to assess future reproductive risks. The study also examined participants' level of agreement with the reasons professional organisations give in favour of deferring such testing. Participants (n=2998) completed a specially designed questionnaire, distributed by email. Nearly half of the sample (47%) agreed that parents should be able to test their child for adult-onset conditions, even if there is no treatment or prevention at time of testing. This runs contrary to professional guidance about genetic testing in children. Testing for carrier status was supported by a larger proportion (60%). A child's future ability to decide for her/himself if and when to be tested was the least supported argument in favour of deferring testing.