Monica Marvin

Report from the National Society of Genetic Counselors Service Delivery Model Task Force: A Proposal to Define Models, Components, and Modes of Referral

The Service Delivery Model Task Force (SDMTF) was appointed in 2009 by the leadership of the National Society of Genetic Counselors (NSGC) with a charge to research and assess the capacity of all existing service delivery models to improve access to genetic counseling services in the context of increasing demand for genetic testing and counseling. In approaching this charge, the SDMTF found that there were varying interpretations of what was meant by “service delivery models” and the group held extensive discussions about current practices to arrive at consensus of proposed definitions for current genetic service delivery models, modes of referral and components of service delivery. The major goal of these proposed definitions is to allow for conversations to begin to address the charge to the committee. We propose that current models of service delivery can be defined by: 1) the methods in which genetic counseling services are delivered (In-person, Telephone, Group and Telegenetics), 2) the way they are accessed by patients (Traditional referral, Tandem, Triage, Rescue and Self-referral) and 3) the variable components that depend upon multiple factors unique to each service setting. This report by the SDMTF provides a starting point whereby standardized terminology can be used in future studies that assess the effectiveness of these described models to overcome barriers to access to genetic counseling services.

AXIN2-Associated Autosomal Dominant Ectodermal Dysplasia and Neoplastic Syndrome

We describe a family with a novel, inherited AXIN2 mutation (c.1989G>A) segregating in an autosomal dominant pattern with oligodontia and variable other findings including colonic polyposis, gastric polyps, a mild ectodermal dysplasia phenotype with sparse hair and eyebrows, and early onset colorectal and breast cancers. This novel mutation predicts p.Trp663X, which is a truncated protein that is missing the last three exons, including the DIX (Disheveled and AXIN interacting) domain. This nonsense mutation is predicted to destroy the inhibitory action of AXIN2 on WNT signaling. Previous authors have described an unrelated family with autosomal dominant oligodontia and a variable colorectal phenotype segregating with a nonsense mutation of AXIN2, as well as a frameshift AXIN2 mutation in an unrelated individual with oligodontia. Our report provides additional evidence supporting an autosomal dominant AXIN2‐associated ectodermal dysplasia and neoplastic syndrome.

The decision to test in women receiving genetic counseling for BRCA1 and BRCA2 mutations.

Functions of genetic counseling include provision of risk information and provision of support in an effort to assist with decision making. This study examines (1) the relationship among intentions to test, self-reported provision of blood sample, and receipt of test results; (2) the impact of genetic counseling on distress specific to gene status, perceived risk of developing breast and ovarian cancer in the context having BRCA1/2 mutations (mutations predisposing to increased risk of breast–ovarian cancer), and perceived risk factors for breast cancer; and (3) the clinical profile of those receiving/not receiving results. Intentions to test for BRCA1/2 mutations, self-reported provision of blood sample immediately after counseling, and receipt of test results were statistically different but highly correlated, and intentions to test increased from pre- to postcounseling. A repeated measures ANOVA found distress specific to gene status and perceived risk factors decreased from pre- to postcounseling. Further, two clinical profiles of consultands emerged: (1) those receiving results with change in intentions to test having lower levels of distress and (2) those not receiving results and those receiving results with no change in intentions to test with higher levels of distress. Our findings are consistent with the function of genetic counseling—to provide information and support to those with familial cancer, as well as to assist in decision making. The provision of support is important as distress specific to gene status may impede flexible decision making about genetic testing.

Cancer Genetics Knowledge and Beliefs and Receipt of Results in Ashkenazi Jewish Individuals Receiving Counseling for BRCA1/2 Mutations

BACKGROUND Genetic counseling for BRCA1 and BRCA2 mutations (mutations associated with increased risk of breast-ovarian cancer) endeavors to communicate information that will help individuals make informed decisions regarding genetic testing. METHODS This repeated-measures study examined cancer genetics knowledge and beliefs before and after counseling and their relationship to receipt of results for BRCA1/2 mutations in 120 highly educated Ashkenazi Jewish individuals. RESULTS A repeated-measures analysis examined change in knowledge and beliefs regarding personal behavior, mechanisms of cancer inheritance, meaning of a positive result, practitioner knowledge, frequency of inherited cancer, and meaning of a negative result from pre- to post-counseling with the between subjects variables of education (with/without graduate training) and personal history of breast or ovarian cancer (yes/no), and risk of having a mutation entered as a covariate. Mechanisms of cancer inheritance, meaning of a positive result, and practitioner knowledge increased from pre- to post-counseling. Those with graduate training had higher ratings of mechanisms of cancer inheritance ratings and lower ratings of frequency of inherited cancers than those without. Mann-Whitney U tests found those testing had higher ratings in mechanisms of cancer inheritance, specifically in the association of multiple primary cancers with hereditary cancer, than those not testing. CONCLUSIONS Genetic counseling is helpful in improving overall knowledge of cancer genetics even for highly educated individuals. Particular areas of knowledge improvement should be explored in relation to receipt of results, especially to further elucidate the relationship of knowledge of the association of multiple primary cancers with hereditary cancer to receipt of test results.

10 rare tumors that warrant a genetics referral.

The number of described cancer susceptibility syndromes continues to grow, as does our knowledge on how to manage these syndromes with the aim of early detection and cancer prevention. Oncologists now have greater responsibility to recognize patterns of cancer that warrant referral for a genetics consultation. While some patterns of common cancers are easy to recognize as related to hereditary cancer syndromes, there are a number of rare tumors that are highly associated with cancer syndromes yet are often overlooked given their infrequency. We present a review of ten rare tumors that are strongly associated with hereditary cancer predisposition syndromes: adrenocortical carcinoma, carcinoid tumors, diffuse gastric cancer, fallopian tube/primary peritoneal cancer, leiomyosarcoma, medullary thyroid cancer, paraganglioma/pheochromocytoma, renal cell carcinoma of chromophobe, hybrid oncocytoic, or oncocytoma histology, sebaceous carcinoma, and sex cord tumors with annular tubules. This review will serve as a guide for oncologists to assist in the recognition of rare tumors that warrant referral for a genetic consultation.

The clinical phenotype of SDHC-associated hereditary paraganglioma syndrome (PGL3).

CONTEXT Mutations in the genes encoding subunits of the succinate dehydrogenase complex cause hereditary paraganglioma syndromes. Although the phenotypes associated with the more commonly mutated genes, SDHB and SDHD, are well described, less is known about SDHC-associated paragangliomas. OBJECTIVE To describe functionality, penetrance, number of primary tumors, biological behavior, and location of paragangliomas associated with SDHC mutations. DESIGN Families with an SDHC mutation were identified through a large cancer genetics registry. A retrospective chart review was conducted with a focus on patient and tumor characteristics. In addition, clinical reports on SDHC-related paragangliomas were identified in the medical literature to further define the phenotype and compare findings. SETTING A cancer genetics clinic and registry at a tertiary referral center. PATIENTS Eight index patients with SDHC-related paraganglioma were identified. RESULTS Three of the eight index patients had mediastinal paraganglioma and four of the eight patients had more than one paraganglioma. Interestingly, the index patients were the only affected individuals in all families. When combining these index cases with reported cases in the medical literature, the mediastinum is the second most common location for SDHC-related paraganglioma (10% of all tumors), occurring in up to 13% of patients. CONCLUSIONS Our findings suggest that thoracic paragangliomas are common in patients with SDHC mutations, and imaging of this area should be included in surveillance of mutation carriers. In addition, the absence of paragangliomas among at-risk relatives of SDHC mutation carriers suggests a less penetrant phenotype as compared to SDHB and SDHD mutations.

Subjective and Objective Risks of Carrying a BRCA1/2 Mutation in Individuals of Ashkenazi Jewish Descent.

This repeated measures study examines (1) the change in subjective risk of mutations pre- to postcounseling, (2) the accuracy of BRCAPRO estimates of mutations, and (3) the discrepancy between subjective risk and BRCAPRO estimates of mutations before and after genetic counseling. Ninety-nine Ashkenazi Jewish individuals pursued testing for BRCA1/2 mutations. Most had a personal cancer history (N = 51; family only: N = 48); and received uninformative negative results (N = 66; positives: N = 23; informative negative: N = 10). The coping strategy of defensive pessimism predicts that individuals will believe the worst case scenario to better cope with a potential negative outcome. Consistent with this, most felt they would have a mutation, if not mutations in both genes. The BRCAPRO model appeared to overestimate risk of having a mutation in this sample (p < .001). BRCAPRO overestimates notwithstanding, genetic counseling increased accuracy of subjective risk (p < .01). Individuals with a family-only cancer history had the least accurate estimates of risk (p < .05) and may need further intervention to either manage anxiety or improve knowledge.

A Case for Inclusion of Genetic Counselors in Cardiac Care.

Recent advances in genetic testing for heritable cardiac diseases have led to an increasing involvement of the genetic counselor in cardiology practice. We present a series of cases collected from a nationwide query of genetics professionals regarding issues related to cost and utilization of genetic testing. Three themes emerged across cases: (1) choosing the most appropriate genetic test, (2) choosing the best person to test, and (3) interpreting results accurately. These cases demonstrate that involvement of a genetic counselor throughout the evaluation, diagnosis, and continuing management of individuals and families with inherited cardiovascular conditions helps to promote the efficient use of healthcare dollars.

A human MUTYH variant linking colonic polyposis to redox degradation of the [4Fe4S]^(2+) cluster

AbstractThe human DNA repair enzyme MUTYH excises mispaired adenine residues in oxidized DNA. Homozygous MUTYH mutations underlie the autosomal, recessive cancer syndrome MUTYH-associated polyposis. We report a MUTYH variant, p.C306W (c.918C>G), with a tryptophan residue in place of native cysteine, that ligates the [4Fe4S] cluster in a patient with colonic polyposis and family history of early age colon cancer. In bacterial MutY, the [4Fe4S] cluster is redox active, allowing rapid localization to target lesions by long-range, DNA-mediated signalling. In the current study, using DNA electrochemistry, we determine that wild-type MUTYH is similarly redox-active, but MUTYH C306W undergoes rapid oxidative degradation of its cluster to [3Fe4S]+, with loss of redox signalling. In MUTYH C306W, oxidative cluster degradation leads to decreased DNA binding and enzyme function. This study confirms redox activity in eukaryotic DNA repair proteins and establishes MUTYH C306W as a pathogenic variant, highlighting the essential role of redox signalling by the [4Fe4S] cluster.The [4Fe4S]2+ cluster-containing DNA-repair enzyme MUTYH helps safeguard the integrity of Watson–Crick base pairing and the human genetic code. The MUTYH [4Fe4S]2+ cluster mediates DNA redox signalling and DNA lesion identification. Now, a MUTYH pathologic variant associated with catastrophic [4Fe4S]2+ cluster redox degradation, impairment of DNA signalling and human colonic tumorigenesis has been identified.

Evaluating and improving the implementation of a community-based hereditary cancer screening program

Healthcare disparities exist in the provision of cancer genetic services including genetic counseling and testing related to BRCA1/2 mutations. To address this in a community health setting a screening tool was created to identify high-risk women. This study evaluates the implementation of the tool and identifies opportunities for improved cancer genetic screening, including regular clinician education. A mixed-method approach was used to evaluate clinician utilization of the screening tool at Planned Parenthood affiliates. Novel surveys that evaluated acceptance and implementation were administered to clinicians (n = 14) and semi-structured interviews (n = 6) were used to explore clinicians’ perspectives and identify gaps in its utilization. Educational modules that addressed gaps were developed, implemented, and evaluated using a post-education survey (n = 8). Clinicians reported confidence in administering and interpreting the screening tool, but reported less confidence in their knowledge of cancer genetics and ability to connect clients with genetic counseling and testing (p = .003). Educational modules resulted in significant gains in clinician knowledge on genetic topics (p < .05) and increased self-reported confidence in connecting clients with genetic services. The modules reinforced the belief that genetic testing is beneficial for patients at increased risk (p = .001) and is important to inform subsequent medical management (p = .027). While building community clinicians’ capacity to connect clients with genetic services is crucial, it is challenged by knowledge and confidence gaps in discussions of genetic services with clients. Consistent genetic-focused education with non-genetic clinicians can improve confidence and knowledge, enabling a more effective screening program in community health settings.