Breadth of Genetic Testing Selected by Patients at Risk of Hereditary Breast and Ovarian Cancer.

OBJECTIVE: The aim of this study was to evaluate the ability of patients at risk of hereditary breast and ovarian cancer (HBOC) syndrome to select the extent of genetic testing personally preferred and the impact of demographic factors on the breadth of testing pursued. METHODS: A single-institution cohort was enumerated consisting of patients referred for clinical genetic counseling secondary to risk of HBOC syndrome. This was a retrospective study of consecutive patients seen for genetic counseling; all patients completed an epidemiologic questionnaire and provided personal and family medical histories. Patients meeting guidelines for testing were offered testing at 3 levels: single gene/condition (Single), small panels with highly penetrant genes (Plus), and large panels with high and moderately penetrant genes (Next). Associations between personal or family-related factors and breadth of testing selected were investigated. Continuous and categorical variables were compared using Student t and χ tests, as appropriate. Joint classification tables were used to test for effect modification, and a log-binomial model was used to compute rate ratios (RR) with a threshold of P < 0.05 considered significant. RESULTS: We identified 253 patients who underwent genetic counseling for HBOC syndrome. Most patients were personally affected by cancer (63.6%), reported at least some college (79.2%), met the National Comprehensive Cancer Network guidelines for BRCA testing (94.5%), and opted to undergo genetic testing (94.1%). Most (84.9%) patients opted for panel testing. An increased likelihood of choosing Next-level testing was found to be associated with patients having any college experience (RR, 1.53; 95% confidence interval, 1.02-2.30), as well as being unaffected by cancer (RR, 1.30; 95% confidence interval, 1.03-1.64). CONCLUSIONS: Clinical genetic counseling is a highly specialized service, which should be provided to patients at risk of hereditary cancer syndromes. Although some epidemiologic factors can predict a patient's preference for testing breadth, patients were sufficiently able to self-identify the level of testing they were comfortable with after receiving genetic counseling. Most practitioners do not have the time or expertise to provide the degree of counseling needed to enable and empower patients to choose the level of testing they are comfortable with. When available, referral to genetic counselors remains an important component of comprehensive care for women with a personal or family history of cancer suggestive of hereditary risk.

Creation and Implementation of an Environmental Scan to Assess Cancer Genetics Services at Three Oncology Care Settings.

An environmental scan (ES) is an efficient mixed-methods approach to collect and interpret relevant data for strategic planning and project design. To date, the ES has not been used nor evaluated in the clinical cancer genetics setting. We created and implemented an ES to inform the design of a quality improvement (QI) project to increase the rates of adherence to national guidelines for cancer genetic counseling and genetic testing at three unique oncology care settings (OCS). The ES collected qualitative and quantitative data from reviews of internal processes, past QI efforts, the literature, and each OCS. The ES used a data collection form and semi-structured interviews to aid in data collection. The ES was completed within 6 months, and sufficient data were captured to identify opportunities and threats to the QI project's success, as well as potential barriers to, and facilitators of guideline-based cancer genetics services at each OCS. Previously unreported barriers were identified, including inefficient genetic counseling appointment scheduling processes and the inability to track referrals, genetics appointments, and genetic test results within electronic medical record systems. The ES was a valuable process for QI project planning at three OCS and may be used to evaluate genetics services in other settings.

Characterizing runs of homozygosity and their impact on risk for psychosis in a population isolate.

An increased abundance of runs of homozygosity (ROH) has been associated with risk for various diseases, including schizophrenia. Here we investigate the characteristics of ROH in Palau, an Oceanic population, evaluating whether these characteristics are related to risk for psychotic disorders and the nature of this association. To accomplish these aims we evaluate a sample of 203 cases with schizophrenia and related psychotic disorders-representing almost complete ascertainment of affected individuals in the population-and contrast their ROH to that of 125 subjects chosen to function as controls. While Palauan diagnosed with psychotic disorders tend to have slightly more ROH regions than controls, the distinguishing features are that they have longer ROH regions, greater total length of ROH, and their ROH tends to co-occur more often at the same locus. The nature of the sample allows us to investigate whether rare, highly penetrant recessive variants generate such case-control differences in ROH. Neither rare, highly penetrant recessive variants nor individual common variants of large effect account for a substantial proportion of risk for psychosis in Palau. These results suggest a more nuanced model for risk is required to explain patterns of ROH for this population.