Impact of subsidies on cancer genetic testing uptake in Singapore

Cascade testing for hereditary cancer in Singapore: how population genomics help guide clinical policy

Hereditary Cancer makes up around 5-10% of all cancers. It is important to diagnose hereditary cancer in a timely fashion, as not only do patients require long-term care from a young age, but their relatives also require management. The main approach to capture at-risk relatives is cascade testing. It involves genetic testing of relatives of the first detected carrier of a pathogenic variant in a family i.e. the proband. The current standard of care for cascade testing is a patient-mediated approach. Probands are then advised to inform and encourage family members to undergo genetic testing. In Singapore, cascade testing is inefficient, around 10-15%, lower than the 30% global average. Here, we describe the cascade testing process and its effort to increase testing in Singapore. Precision Health Research, Singapore (PRECISE), was set up to coordinate Singapore's National Precision Medicine strategy and has awarded five clinical implementation pilots, with one of them seeking to identify strategies for how cascade testing for hereditary cancer can be increased in a safe and cost-efficient manner. Achieving this will be done through addressing barriers such as cost, manpower shortages, exploring a digital channel for contacting at-risk relatives, and getting a deeper insight into why genetic testing gets declined. If successful, it will likely result in care pathways that are a cost-effective public health intervention for identifying individuals at risk. Surveillance and management of those unaffected at-risk individuals, if caught early, will result in improved patient outcomes, and further reduce the healthcare burden for the economy.

Current practices and challenges in genetic testing and counseling for women with breast and ovarian cancer in Asia

AIM

This study assesses current practices and challenges in genetic testing and counseling (GT and C) for breast cancer gene (BRCA)1/2 mutations in Asia, considering the increased risk of ovarian cancer (OC) and breast cancer (BC) in women carrying these mutations.

METHODS

Insights were gathered through a questionnaire from breast surgeons, gynecologists, oncologists, and genetic clinicians in 10 Asian countries: Thailand, Hong Kong, South Korea, India, Vietnam, Malaysia, the Philippines, Taiwan, Singapore, and Indonesia. The questionnaire covered their knowledge, attitudes, and practices in GT and C for BRCA1/2 mutations, along with information on perceived gaps and unmet needs in the region.

RESULTS

A total of 61 specialists participated in the survey. GT and C for BRCA1/2 mutations were less frequently offered in Asia compared to Western countries. Among the guidelines used, the National Comprehensive Cancer Network (NCCN) guidelines alone or in combination with other guidelines (American Society of Clinical Oncology [ASCO], National Institute for Health and Clinical Excellence [NICE], and European Society for Medical Oncology [ESMO]) were preferred for both BC and OC. Limited access to genetic counselors posed a significant challenge, resulting in delayed or no GT. Pretest genetic counseling was provided by the respondents themselves. Germline testing was preferred for BC, whereas both germline and somatic testing were preferred for OC, with the most preferred option being a multipanel germline test.

CONCLUSION

Disparities exist in GT and C practices between Asian and Western countries. To address this, steps, such as patient and doctor education, increased accessibility and affordability of GT and C services, and improved infrastructure for identifying gene mutations, should be taken.

Challenges in genetic screening for inherited endocrinopathy affecting the thyroid, parathyroid and adrenal glands in Singapore

Significant progress has been made in the understand-ing of many human diseases, especially cancers, which has contributed to improved and increased survival. The Human Genome Project and The Cancer Genome Atlas project brought about a new era, with an understanding of inherited diseases at a molecular level, which subsequently facilitated the option of precision medicine. Precision medicine has helped tailor treatment decisions at an individual level, for instance in terms of surgical treatments or targeted therapies in advanced diseases. Despite the increasing advances in genetic-lead precision medicine, this has not translated into increasing uptake among patients. Reasons for this may be potential knowledge gaps among clinicians; on reasons for poor uptake of genetic testing such as for cultural, religious or personal beliefs; and on financial implications such as lack of support from insurance companies. In this review, we look at the current scenario of genetic screening for common inherited endocrine conditions affecting the thyroid, parathyroid and adrenal glands in Singapore, and the implications associated with it.

Strategies to improve implementation of cascade testing in hereditary cancer syndromes: a systematic review

Hereditary cancer syndromes constitute approximately 10% of all cancers. Cascade testing involves testing of at-risk relatives to determine if they carry the familial pathogenic variant. Despite growing efforts targeted at improving cascade testing uptake, current literature continues to reflect poor rates of uptake, typically below 30%. This study aims to systematically review current literature on intervention strategies to improve cascade testing, assess the quality of intervention descriptions and evaluate the implementation outcomes of listed interventions. We searched major databases using keywords and subject heading of "cascade testing". Interventions proposed in each study were classified according to the Effective Practice and Organization of Care (EPOC) taxonomy. Quality of intervention description was assessed using the TIDieR checklist, and evaluation of implementation outcomes was performed using Proctor's Implementation Outcomes Framework. Improvements in rates of genetic testing uptake was seen in interventions across the different EPOC taxonomy strategies. The average TIDieR score was 7.3 out of 12. Items least reported include modifications (18.5%), plans to assess fidelity/adherence (7.4%) and actual assessment of fidelity/adherence (7.4%). An average of 2.9 out of 8 aspects of implementation outcomes were examined. The most poorly reported outcomes were cost, fidelity and sustainability, with only 3.7% of studies reporting them. Most interventions have demonstrated success in improving cascade testing uptake. Uptake of cascade testing was highest with delivery arrangement (68%). However, the quality of description of interventions and assessment of implementation outcomes are often suboptimal, hindering their replication and implementation downstream. Therefore, further adoption of standardized guidelines in reporting of interventions and formal assessment of implementation outcomes may help promote translation of these interventions into routine practice.

Prevalence and genetic spectrum associated with hereditary colorectal cancer syndromes, the need to improve cancer risk awareness, and family cascade testing in Vietnam

In Vietnam, colorectal cancer is one of the top diagnosed cancers, with 5-10% originating from inherited mutations. This study aims to define the mutation spectrum associated with hereditary colorectal cancer syndromes (HCCS) in Vietnam, evaluate the influence of genetic testing on carriers' awareness, and also investigate the barriers in familial testing. Genetic test reports were collected to identify HCCS cases, then cases underwent a survey investigating self-risk and familial-risk awareness, proactive cancer screening, and familial testing barriers. Participant characteristics, mutation prevalence, and results from the survey were descriptively analyzed and reported. Of all genetic test results, 3% (49/1632) were identified with mutations related to HCCS. Over 77% of them belonged to Lynch syndrome. PMS2 appeared to be the gene with the highest mutation frequency, while MLH1 was the lowest. 44% of cases further undertook cancer screening tests, and 48% of cases' families had uptake genetic testing. The biggest barrier of familial members for not taking genetic test was psychological reasons (fear, not being interested, or not feeling necessary). This study provided new evidence for HCCS mutation spectrum in Vietnamese population and the success in promoting cascade test in high-risk family members through financial and technical support. Also, study has suggested the needs of an innovative genetic testing process focusing on the quality of pre-and post-test consultancy, an increase in follow-ups, and the change in policy for permission of contacting relatives directly to improve the rate of cascade testing and proactive cancer screening.

Cascade Testing for Hereditary Cancer Syndromes: Should We Move Toward Direct Relative Contact? A Systematic Review and Meta-Analysis

PURPOSE

Evidence-based guidelines recommend cascade genetic counseling and testing for hereditary cancer syndromes, providing relatives the opportunity for early detection and prevention of cancer. The current standard is for patients to contact and encourage relatives (patient-mediated contact) to undergo counseling and testing. Direct relative contact by the medical team or testing laboratory has shown promise but is complicated by privacy laws and lack of infrastructure. We sought to compare outcomes associated with patient-mediated and direct relative contact for hereditary cancer cascade genetic counseling and testing in the first meta-analysis on this topic.

MATERIALS AND METHODS

We conducted a systematic review and meta-analysis in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PROSPERO No.: CRD42020134276). We searched key electronic databases to identify studies evaluating hereditary cancer cascade testing. Eligible trials were subjected to meta-analysis.

RESULTS

Eighty-seven studies met inclusion criteria. Among relatives included in the meta-analysis, 48% (95% CI, 38 to 58) underwent cascade genetic counseling and 41% (95% CI, 34 to 48) cascade genetic testing. Compared with the patient-mediated approach, direct relative contact resulted in significantly higher uptake of genetic counseling for all relatives (63% [95% CI, 49 to 75] v 35% [95% CI, 24 to 48]) and genetic testing for first-degree relatives (62% [95% CI, 49 to 73] v 40% [95% CI, 32 to 48]). Methods of direct contact included telephone calls, letters, and e-mails; respective rates of genetic testing completion were 61% (95% CI, 51 to 70), 48% (95% CI, 37 to 59), and 48% (95% CI, 45 to 50).

CONCLUSION

Most relatives at risk for hereditary cancer do not undergo cascade genetic counseling and testing, forgoing potentially life-saving medical interventions. Compared with patient-mediated contact, direct relative contact increased rates of cascade genetic counseling and testing, arguing for a shift in the care delivery paradigm, to be confirmed by randomized controlled trials.

Male breast cancer: a Singapore perspective

INTRODUCTION

Male breast cancer (MBC) is rare, representing <1% of all breast cancers. Treatment recommendations have been extrapolated from trial data of female breast cancer patients. This study aims to report our institutional experience of MBC across a 20 year period, analyse the survival outcome and prognosis of this group against female breast cancer patients treated at the same centre.

METHODS

Clinical, histopathological, treatment and survival data of male and female breast cancer patients treated between Jan 1999 and July 2019 at Singapore General Hospital and National Cancer Centre Singapore were identified and analysed.

RESULTS

Fifty-seven male patients were identified. The median age at diagnosis was 63 years. Majority had invasive ductal carcinoma (86%) and presented at an early disease stage: 70.2% presented as Tis/T1/T2 and 49.1% had no axillary nodal involvement. 84.2% had a simple mastectomy with either a sentinel lymph node biopsy or axillary clearance. The median follow up was 5.69 years for males and 5.83 years for females. The median survival was 11.86 years for males and 16.3 years for females. At 5 years, overall survival (OS) was 69.9% (52.3-82.1%) and disease free survival (DFS) was 62.9% (44.9-76.5%) for males compared with OS 83.8% (83.21-84.39%) and DFS 74.5% (73.91-75.09%) for females.

CONCLUSION

MBC remains understudied. Our institutional data indicates that good long term survival in South-East Asian patients can be achieved with treatment protocols that are similar to female breast cancer. More prospective studies are required.

Impact of Variant Reclassification in Cancer Predisposition Genes on Clinical Care

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Sharing genetic test results of germline pathogenic variants of hereditary cancer with relatives: A single-center cross-sectional study

Objective

This study aimed to determine whether Japanese cancer patients share test results of germline pathogenic variants of hereditary cancer with their relatives.

Methods

This single-center cross-sectional study enrolled 21 Japanese patients who received results of germline pathogenic variants of hereditary cancer at least 6 months prior.

Results

All patients shared their test results with at least one relative, with the following sharing rates: 85.7% for first-degree relatives, 10% for second-degree relatives and 8.3% for third-degree relatives. Patients most commonly shared the information with their children aged >18 years (86.7%), followed by their siblings (73.6%), spouses (64.7%) and parents (54.5%). Three categories were extracted from qualitative analysis: ‘characteristics of my cancer’, ‘knowledge and caution about inheritability’ and ‘utilization of medical care.’

Conclusions

The rate of test result sharing with first-degree relatives was comparable with those in Europe and the USA. Patients with germline pathogenic variants also tended to share their test results more with their children and siblings than with their parents. Informing their relatives of the results was suggestive of the motivation to influence their relatives’ health outcome and contribute to the well-being of their children and siblings.

Utilization and uptake of clinical genetics services in high-income countries: A scoping review

Ongoing rapid growth in the need for genetic services has the potential to severely strain the capacity of the clinical genetics workforce to deliver this care. Unfortunately, assessments of the scale of this health policy challenge and potential solutions are hampered by the lack of a consolidated evidence base on the growth in genetic service utilization. To enable health policy research and strategic planning by health systems in this area, we conducted a scoping review of the literature on the utilization and uptake of clinical genetics services in high-income countries published between 2010 and 2018. One-hundred-and-ninety-five unique studies were included in the review. Most focused on cancer (85/195; 44%) and prenatal care (50/195; 26%), which are consistently the two areas with the greatest volume of genetic service utilization in both the United States and other high-income countries. Utilization and uptake rates varied considerably and were influenced by contextual factors including health system characteristics, provider knowledge, and patient preferences. Moreover, growth in genetic service utilization appears to be driven to a significant degree by technological advances and the integration of new tests into clinical care. Our review highlights both the policy challenge posed by the rapid growth in the utilization of genetic services and the variability in this trend across clinical indications and health systems.

Clinical implementation of an oncology-specific family health history risk assessment tool

BACKGROUND

The presence of hereditary cancer syndromes in cancer patients can have an impact on current clinical care and post-treatment prevention and surveillance measures. Several barriers inhibit identification of hereditary cancer syndromes in routine practice. This paper describes the impact of using a patient-facing family health history risk assessment platform on the identification and referral of breast cancer patients to genetic counselling services.

METHODS

This was a hybrid implementation-effectiveness study completed in breast cancer clinics. English-literate patients not previously referred for genetic counselling and/or gone through genetic testing were offered enrollment. Consented participants were provided educational materials on family health history collection, entered their family health history into the platform and completed a satisfaction survey. Upon completion, participants and their clinicians were given personalized risk reports. Chart abstraction was done to identify actions taken by patients, providers and genetic counsellors.

RESULTS

Of 195 patients approached, 102 consented and completed the study (mean age 55.7, 100 % women). Sixty-six (65 %) met guideline criteria for genetic counseling of which 24 (36 %) were referred for genetic counseling. Of those referred, 13 (54 %) participants attended and eight (33 %) completed genetic testing. On multivariate logistic regression, referral was not associated with age, cancer stage, or race but was associated with clinical provider (p = 0.041). Most providers (71 %) had higher referral rates during the study compared to prior. The majority of participants found the experience useful (84 %), were more aware of their health risks (83 %), and were likely to recommend using a patient-facing platform to others (69 %).

CONCLUSIONS

65 % of patients attending breast cancer clinics in this study are at-risk for hereditary conditions based on current guidelines. Using a patient-facing risk assessment platform enhances the ability to identify these patients systematically and with widespread acceptability and recognized value by patients. As only a third of at-risk participants received referrals for genetic counseling, further understanding barriers to referral is needed to optimize hereditary risk assessment in oncology practices.

TRIAL REGISTRATION

NIH Clinical Trials registry, NCT04639934 . Registered Nov 23, 2020 -- Retrospectively registered.

Cost-effectiveness of olaparib versus routine surveillance in the maintenance setting for patients with BRCA-mutated advanced ovarian cancer after response to first-line platinum-based chemotherapy in Singapore

Objective

To evaluate the cost-effectiveness of olaparib as a maintenance treatment versus routine surveillance (RS) in patients with BRCA mutated (BRCAm) advanced ovarian cancer (OC) following response to first-line platinum-based chemotherapy in Singapore.

Methods

A 4-health state partitioned survival model was developed to simulate the lifetime (50 years) incremental cost-effectiveness ratio (ICER) of olaparib versus RS from a healthcare payer perspective. Progression-free survival, time to second disease progression, and overall survival were estimated using SOLO-1 data and extrapolated beyond the trial period using parametric survival models. Any patient who remained progression-free at year 7 was assumed to be no longer at risk of progression. Mortality rates were based on all-cause mortality, adjusted based on BRCA1/2 mutation. Health state utilities and adverse event frequencies were from SOLO-1. Drug costs were from local public healthcare institutions. Healthcare resource usage and costs were from local clinician input and publications. A 3% discount rate was applied to costs and outcomes. Deterministic and probabilistic sensitivity analyses (PSA) were performed to assess the robustness of results.

Results

The base-case analysis of olaparib maintenance therapy versus RS resulted in an ICER of Singapore dollar (SGD) 19,822 per quality-adjusted life-year (QALY) gained. The ICER was most sensitive to variations in the discount rate. PSA demonstrated that olaparib had an 87% probability of being cost-effective versus RS at a willingness-to-pay of SGD 60,000 per QALY gained.

Conclusion

Olaparib has a high potential of being a cost-effective maintenance treatment versus RS for patients with BRCA1/2m advanced OC after response to first-line chemotherapy in Singapore.

An in-depth exploration of the post-test informational needs of BRCA1 and BRCA2 pathogenic variant carriers in Asia

Introduction

Identification of one's status as a BRCA1/2 pathogenic variant carrier often marks the start of navigating challenging decisions related to cancer risk management and result disclosure. Carriers report unmet informational needs, but studies have yet to explore the specific aspects of and how best to fulfill these needs. This study aims to explore the informational needs of BRCA1/2 pathogenic variant carriers in Asia to inform for the design of educational materials to support risk management decision-making.

Methods

Semi-structured in-depth interviews were conducted with two male and 22 female English-speaking BRCA1/2 pathogenic variant carriers, aged 29-66 years, identified through the Cancer Genetics Service at the National Cancer Centre Singapore. A grounded theory approach with thematic analysis was undertaken to extract dominant themes.

Results

Four themes were identified: (i) proactive online information seeking behaviors (ii) personalized informational needs; (iii) challenges in sharing the results; and (iv) lack of genetic awareness.

Discussion

Participants highlight challenges with sharing their result arising from significant post-result informational needs, which have manifested into proactive online information-seeking behaviors. They desire for an online source of information, where content is personalized, reliable and local. Participants foresee the potential of an online resource to raise genetic awareness. This suggests the use of a culturally tailored online-based genetics resource, to promote result disclosure, empower risk-management decisions and raise genetic literacy rates.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s13053-020-00154-x.

Predictive Testing for Tumor Predisposition Syndromes in Pediatric Relatives: An Asian Experience

Approximately 10% of pediatric cancer patients possess germline pathogenic/likely pathogenic variants (PV/LPV) in known tumor predisposition genes. Predictive testing is the optimal approach to identify asymptomatic at-risk relatives to guide gene-directed surveillance for early cancer detection and/or risk-reducing strategies. However, the uptake rate for predictive testing remains low in Asian countries. We aim to evaluate the uptake rate of predictive testing in a pediatric population (aged under 21-years-old) in a multi-ethnic Asian cancer center. Our retrospective analysis included families with PV/LPVs identified in genes associated with pediatric tumor predisposition. Of the 83 pediatric first-degree relatives (FDRs) from 49 unrelated families, 20 FDRs (24.1%) originating from 13 families (26.6%) underwent predictive testing. Genes tested in pediatric FDRs were APC, RB1, SBDS, SDHA, SDHB, SDHD, and TP53. All pediatric FDRs of probands with PV/LPVs in RB1 and biallelic PVs in SBDS underwent predictive testing, while <45% of pediatric FDRs had predictive testing for familial PV/LPVs identified in the APC, SDHA, SDHB, SDHD, and TP53 genes. Amongst the 13 families who underwent pre-test counseling, 80% of pediatric FDRs in these families proceeded with predictive testing. Malay pediatric FDRs and siblings of probands were more likely to undergo predictive testing. We conclude that the predictive testing rate in pediatric FDRs is higher than that of adult FDRs in Asia, but still below the global average. We postulate factors that may influence predictive testing uptake in pediatric FDRs includes a lack of genetics awareness, concerns regarding insurance, and genetic discrimination.

Impact of free cancer predisposition cascade genetic testing on uptake in Singapore

Cascade testing for cancer predisposition offers a highly efficient and cost-effective method for identifying individuals at increased risk for cancer, in whom targeted interventions can often improve survival. The aim of this study was to determine the impact of free cascade testing on uptake and identify other associated factors. Demographic and clinical data were gathered prospectively for 183 probands found to have a pathogenic variant associated with cancer predisposition and their 826 first-degree relatives (FDRs). The provision of free cascade testing was significantly associated with uptake (21.6% vs 6.1%; χ ², P < 0.001). Relationship type between FDR and proband and FDR age also demonstrated significant associations, suggesting greater engagement amongst younger generations. Overall, 29.0% (53/183) of families had at least 1 FDR who underwent cascade testing. Of these families, 67.9% (36/53) had an uptake rate of at least 40.0%. Cost is a significant barrier to cascade testing uptake in Singapore. Tailored interventions targeting underrepresented groups and genetic counseling approaches supporting family communication and decision-making are necessary.

Family health history: underused for actionable risk assessment

Family health history (FHH) is the most useful means of assessing risk for common chronic diseases. The odds ratio for risk of developing disease with a positive FHH is frequently greater than 2, and actions can be taken to mitigate risk by adhering to screening guidelines, genetic counselling, genetic risk testing, and other screening methods. Challenges to the routine acquisition of FHH include constraints on provider time to collect data and the difficulty in accessing risk calculators. Disease-specific and broader risk assessment software platforms have been developed, many with clinical decision support and informatics interoperability, but few access patient information directly. Software that allows integration of FHH with the electronic medical record and clinical decision support capabilities has provided solutions to many of these challenges. Patient facing, electronic medical record, and web-enabled FHH platforms have been developed, and can provide greater identification of risk compared with conventional FHH ascertainment in primary care. FHH, along with cascade screening, can be an important component of population health management approaches to overall reduction of risk.

Global Disparities in Breast Cancer Genetics Testing, Counselling and Management

Hereditary breast cancers, mainly due to BRCA1 and BRCA2 mutations, account for only 5-10% of this disease. The threshold for genetic testing is a 10% likelihood of detecting a mutation, as determined by validated models such as BOADICEA and Manchester Scoring System. A 90-95% reduction in breast cancer risk can be achieved with bilateral risk-reducing mastectomy in unaffected BRCA mutation carriers. In patients with BRCA-associated breast cancer, there is a 40% risk of contralateral breast cancer and hence risk-reducing contralateral mastectomy is recommended, which can be performed simultaneously with surgery for unilateral breast cancer. Other options for risk management include surveillance by mammogram and breast magnetic resonance imaging, and chemoprevention with hormonal agents. With the advent of next-generation sequencing and development of multigene panel testing, the cost and time taken for genetic testing have reduced, making it possible for treatment-focused genetic testing. There are also drugs such as the PARP inhibitors that specifically target the BRCA mutation. Risk management multidisciplinary clinics are designed to quantify risk, and offer advice on preventative strategies. However, such services are only possible in high-income settings. In low-resource settings, the prohibitive cost of testing and the lack of genetic counsellors are major barriers to setting up a breast cancer genetics service. Family history is often not well documented because of the stigma associated with cancer. Breast cancer genetics services remain an unmet need in low- and middle-income countries, where the priority is to optimise access to quality treatment.

Implementation of genomics in medical practice to deliver precision medicine for an Asian population

Whilst the underlying principles of precision medicine are comparable across the globe, genomic references, health practices, costs and discrimination policies differ in Asian settings compared to the reported initiatives involving European-derived populations. We have addressed these variables by developing an evolving reference base of genomic and phenotypic data and a framework to return medically significant variants to consenting research participants applicable for the Asian context. Targeting 10,000 participants, over 2000 Singaporeans, with no known pre-existing health conditions, have consented to an extensive clinical health screen, family health history collection, genome sequencing and ongoing follow-up. Genomic variants in a subset of genes associated with Mendelian disorders and drug responses are analysed using an in-house bioinformatics pipeline. A multidisciplinary team reviews the classification of variants and a research report is generated. Medically significant variants are returned to consenting participants through a bespoke return-of-result genomics clinic. Variant validation and subsequent clinical referral are advised as appropriate. The design and implementation of this flexible learning framework enables a cohort of detailed phenotyping and genotyping of healthy Singaporeans to be established and the frequency of disease-causing variants in this population to be determined. Our findings will contribute to international precision medicine initiatives, bridging gaps with ethnic-specific data and insights from this understudied population.

Risk management adherence following genetic testing for hereditary cancer syndromes: a Singaporean experience

Assessing adherence behavior among mutation carriers to cancer risk management guidelines is important for both service improvement and cost-effectiveness analyses, but such real-world data is often lacking. The present study aims to report adherence rates among mutation carriers in a recently established cancer genetics program in Singapore. We conducted a medical chart review of mutation carriers who had attended for genetic counseling and gathered data regarding risk management behavior, including cancer surveillance and/or risk-reducing surgery, and cancers subsequently detected. Of the 52 subjects included in the study, the majority were affected prior to genetic testing (78.8%) and had family history suggestive of a germline mutation (88.5%). The overall adherence rate was 96.2%, including 37 (74.0%) fully-adherent and 13 (26.0%) partially-adherent subjects, with five cancers subsequently detected. Among the 28 BRCA1/2 mutation carriers, adherence to breast cancer risk management was also high (89.3%), although uptake of risk-reducing bilateral salpingo-oophorectomy was not as common (60%). Whilst overall adherence in this cohort was high, BRCA1/2 mutation carriers may require targeted interventions to improve ovarian cancer risk management uptake. Additionally, further education among health professionals and the wider community regarding cancer genetics is needed to ensure the early identification of mutation carriers.

The influence of Malay cultural beliefs on breast cancer screening and genetic testing: A focus group study

OBJECTIVE

Malays comprise an Asian cultural group reported to have low breast cancer screening uptake rates and poor cancer outcomes. Little is known about Malay cultural factors influencing beliefs and practice of cancer screening and genetic testing. Our study aims to explore health beliefs of Malay women around breast cancer screening and genetic testing.

METHODS

We conducted focus groups among healthy English-speaking Malay women in Singapore, aged 40 to 69 years, using a structured guide developed through literature review, expertise input and participant refinement. Thematic analysis was conducted to extract dominant themes representing key motivators and barriers to screening and genetic testing. We used grounded theory to interpret results and derive a framework of understanding, with implications for improving uptake of services.

RESULTS

Five focus groups (four to six participants per group) comprising 27 women were conducted to theme saturation. Major themes were (a) spiritual and religious beliefs act as barriers towards uptake of screening and genetic testing; (b) preference for traditional medicine competes with Western medicine recommendations; (c) family and community influence health-related decisions, complexed by differences in intergenerational beliefs creating contrasting attitudes towards screening and prevention.

CONCLUSIONS

Decisions to participate in breast cancer screening and genetic testing are influenced by cultural, traditional, spiritual/religious, and intergenerational beliefs. Strategies to increase uptake should include acknowledgement and integration of these beliefs into counseling and education and collaboration with key influential Malay stakeholders and leaders.

Predictors of next-generation sequencing panel selection using a shared decision-making approach

The introduction of next-generation sequencing panels has transformed the approach for genetic testing in cancer patients, however, established guidelines for their use are lacking. A shared decision-making approach has been adopted by our service, where patients play an active role in panel selection and we sought to identify factors associated with panel selection and report testing outcomes. Demographic and clinical data were gathered for female breast and/or ovarian cancer patients aged 21 and over who underwent panel testing. Panel type was classified as ‘breast cancer panel’ (BCP) or ‘multi-cancer panel’ (MCP). Stepwise multiple logistic regression analysis was used to identify clinical factors most predictive of panel selection. Of the 265 included subjects, the vast majority selected a broader MCP (81.5%). Subjects who chose MCPs were significantly more likely to be ≥50 years of age (49 vs. 31%; p < 0.05), Chinese (76 vs. 47%; p < 0.001) and have a personal history of ovarian cancer (41 vs. 8%; p < 0.001) with the latter two identified as the best predictors of panel selection. Family history of cancer was not significantly associated with panel selection. There were no statistically significant differences in result outcomes between the two groups. In summary, our findings demonstrate that the majority of patients have a preference for interrogating a larger number of genes beyond those with established testing guidelines, despite the additional likelihood of uncertainty. Individual factors, including cancer history and ethnicity, are the best predictors of panel selection.

Thanks to next-generation sequencing (NGS) it is possible to test multiple genes for cancer susceptibility quickly and cheaply. At the National Cancer Centre Singapore, shared decision-making is used to actively encourage the involvement of patients in the selection of either a ‘breast cancer panel’ (BCP) or a broader ‘multi-cancer panel’ (MCP) test. Joanne Ngeow at the Centre’s Cancer Genetics Service and colleagues examined the choices made by 265 patients with breast and/or ovarian cancer following detailed pre-test counselling by the genetics team. The majority of patients selected the MCP, potentially highlighting a willingness to accept the additional uncertainty that comes with broader NGS panels. Interestingly, a personal history of ovarian cancer and Chinese ethnicity, but not a family history of cancer, were significantly associated with panel selection.

Clinical management of pheochromocytoma and paraganglioma in Singapore: missed opportunities for genetic testing

Background

Pheochromocytomas and paragangliomas (PPGLs) are neuroendocrine tumors of the adrenal glands and paraganglia, occurring sporadically or as a range of hereditary tumor syndromes. About 30% of PPGLs are attributed to germline mutations. Clinical presentation, including localization, malignant potential, and age of onset, varies depending on the genetic background. Genetic testing for PPGLs is not well studied in Southeast Asia. We reviewed clinical management of PPGLs in Singapore, highlighting current gaps in clinical practice.

Methods

Medical records of patients with PPGLs between 2005 and 2016 were reviewed. Diagnosis was confirmed histologically and stratified into sporadic or familial/syndromic (FS).

Results

Twenty‐seven (21.8%) patients were referred to the Cancer Genetics Service (CGS). FS PPGLs (18.5%) and extra‐adrenal PPGLs (58.1%) incidences were higher than previous studies. Referrals were lower for sporadic PPGLs compared to FS PPGLs (3.7% vs. 100%). Referrals were highest at diagnosis age <20 years old (80%) and decreased with increasing age; ≥20–<40 years old (32.1%), ≥40–<60 years old (10.6%). Genetic testing was taken up in 12/27 (44.4%) patients of which 7/12 (58.3%, 3 SDHB, 2 SDHD, 2 VHL) had germline mutations.

Conclusion

Opportunities for genetic testing are frequently missed due to low referral rates in patients with apparently sporadic PPGLs, particularly between ages 20‐60.

Traceback: A Proposed Framework to Increase Identification and Genetic Counseling of BRCA1 and BRCA2 Mutation Carriers Through Family-Based Outreach

In May 2016, the Division of Cancer Prevention and the Division of Cancer Control and Population Sciences, National Cancer Institute, convened a workshop to discuss a conceptual framework for identifying and genetically testing previously diagnosed but unreferred patients with ovarian cancer and other unrecognized BRCA1 or BRCA2 mutation carriers to improve the detection of families at risk for breast or ovarian cancer. The concept, designated Traceback, was prompted by the recognition that although BRCA1 and BRCA2 mutations are frequent in women with ovarian cancer, many such women have not been tested, especially if their diagnosis predated changes in testing guidelines. The failure to identify mutation carriers among probands represents a lost opportunity to prevent cancer in unsuspecting relatives through risk-reduction intervention in mutation carriers and to provide appropriate reassurances to noncarriers. The Traceback program could provide an important opportunity to reach families from racial, ethnic, and socioeconomic groups who historically have not sought or been offered genetic counseling and testing and thereby contribute to a reduction in health disparities in women with germline BRCA mutations. To achieve an interdisciplinary perspective, the workshop assembled international experts in genetics, medical and gynecologic oncology, clinical psychology, epidemiology, genomics, cost-effectiveness modeling, pathology, bioethics, and patient advocacy to identify factors to consider when undertaking a Traceback program. This report highlights the workshop deliberations with the goal of stimulating research and providing a framework for pilot studies to assess the feasibility and ethical and logistical considerations related to the development of best practices for implementation of Traceback studies.