Genetic counselor approaches to BRCA1/2 direct‐to‐consumer genetic testing results

Abstract

The National Comprehensive Cancer Network recommends clinical-grade genetic testing to confirm commercial results from direct-to-consumer genetic testing (DTC-GT) companies and third-party interpretation (TPI) services; however, the type of confirmatory testing that genetic counselors (GCs) recommend remains uncharacterized. Therefore, we aimed to describe GCs testing strategies for patients who have already obtained DTC-GT results (23andMe) or TPI data (Promethease) that reported a BRCA1/2 pathogenic variant. We invited GCs specializing in clinical cancer genetics to complete an online survey distributed to members of the National Society of Genetic Counselors. The survey, completed by 80 respondents, contained case scenarios featuring probands with variable personal and family histories of cancer. Our results show that the majority of participating GCs have counseled patients for their health-related commercial test results; 94% have encountered patient DTC-GT reports (3 per year), and 69% have encountered patient TPI data (2 per year). Most participating GCs would recommend confirmatory clinical-grade testing for probands with a positive 23andMe BRCA1/2 result (77/80, 96%). However, there was strong variability between the type of recommended testing. Approximately 20% recommended singlesite analysis, 11%-14% recommended the three Ashkenazi Jewish BRCA1/2 founder mutations, 4% recommended BRCA1/2 testing, and 61%-64% recommended multigene panel testing. The most commonly recommended panels were split between a breast and gynecological cancer-focused panel and a broad pan-cancer panel. The majority of participants (98%-100%) would also recommend confirmatory testing for patients with positive TPI data for BRCA1/2. Similarly, results were mixed between those who recommended targeted, single-site analysis (10%-15%) compared to a multi-gene panel (72%-83%). These data show that while most GCs were uniform in their practice of recommending confirmatory testing, they are mixed in their approach to the specific type of testing they would select. These results may help inform counseling approaches and consensus for this expanding group of patients.

Direct-to-consumer genetic testing: an updated systematic review of healthcare professionals’ knowledge and views, and ethical and legal concerns

“…These 24 providers were divided into 5 focus groups. Prostate Cancer Burke et al [ 26 ] (USA and Canada) “To describe GCs testing strategies for patients who have already obtained DTC-GT results (23andMe) or TPI data (Promethease) that reported a BRCA1/2 pathogenic variant.” Cross-sectional design: online survey (7%) 80 genetic counsellors that were members of the National Society of Genetic Counsellors (reporting clinical cancer genetics as their primary specialty) Breast and gynaecological cancer: BRCA1/2 Carroll et al [ 27 ] (Canada) “To assess primary care providers’ experiences with, perceptions of, and desired role in personalised medicine, with a focus on cancer. Qualitative study: focus groups (N/A (“purposeful sampling” used) 51 primary care providers (30 family physicians, 11 registered nurses, 2 nurse practitioners, 1 physician assistant, 4 family medicine residents, 1 medical student, 2 not specified) Non-specific DTC-GT Carroll et al [ 28 ] (Canada) “To determine family physicians’ (FP) current involvement and confidence in GM, attitudes regarding its clinical value, suggestions for integration of GM into practice, and resources and education required.” Quantitative: anonymous questionnaire (26% adjusted response rate) 361 family physicians from the Scott’s Directory of Canadian physicians Non-specific DTC-GT Chambers et al [ 21 ] (USA) “The purpose of our study was to determine whether PCPs have improved in experience, confidence, and ability to order genetic testing since the recent surge of clinically relevant tests and well publicised rise and fall of affordable DTC genetic tests.” Quantitative: surveys sent by mail (37.80%) 310 PCPs: 204 family medicine physicians, 70 internal medicine physicians, 36 from other medical specialities Non-specific DTC-GT Haga et al [ 29 ] (USA) “Evaluated PCPs’ awareness of the role of genetics/genomics in health, knowledge about key concepts in genomic medicine, perception/attitudes towards direct-to-consumer (DTC) genetic testing, and their level of confidence/comfort in discussing testing with patients prior to and after undergoing DTC testing through the 23andMe Health+ Ancestry Service.” Quantitative: web-based survey (<1%) 130 registered PCPs (active physicians in the United States—facilitated by IQVIA, a health data science and clinical research company): 82 in family practice and 48 in internal medicine Ancestry, health predisposition-genetic health risk, carrier status, traits and wellness Howard and Borry [ 2 ] (Europe (28 Countries)) To “present empirical evidence, both quantitative and qualitative, regarding the awareness of, experiences with, and attitudes towards DTC...…”

“…Sixteen studies used survey methods, of which eleven were online [ 2 , 24 , 26 , 29 – 36 ], three by mail [ 21 , 28 , 37 ], one on paper [ 38 ], and one used both mail and on paper [ 25 ]. Two studies involved focus groups [ 25 , 27 ], one with a pre- and post-focus group survey [ 25 ], and one used semi-structured interviews [ 22 , 23 ].…”

“…Eight studies had less than a 20% response rate [ 26 , 29 – 32 , 34 – 36 ], six studies had between 21 and 50% response rate [ 2 , 21 , 24 , 28 , 33 , 37 ], and one study had a response rate of 60% [ 38 ]. Similarly, participant numbers varied across the survey-based studies; six had less than 200 participants [ 2 , 26 , 29 , 32 , 35 , 37 ], six studies had between 201 and 500 participants [ 21 , 28 , 30 , 34 , 36 , 38 ], one study had 502 participants [ 24 ], and two studies had more than 1000 participants [ 31 , 33 ]. The two focus group studies had 24 and 51 participants, and the semi-structured interview study had 15 participants [ 22 , 23 , 25 , 27 ].…”

“…Four studies had medical specialists in their participant groups: one study involved psychiatrists and neurologists [ 36 ], one study involved urologists [ 25 ], and two involved a small number of other medical specialists [ 21 , 34 ]. Five studies involved GCs [ 26 , 30 , 32 , 34 , 35 ]. Two studies involved only CGs as participants [ 22 , 23 , 35 ] and one study had CGs represent 1.5% of their participant group [ 34 ].…”

“…Genetic specialists had more DTC-GT experience than other HCPs, with 58% of genetic specialists versus 17% of PCPs had experience with patients bringing them personal DTC-GT results [ 34 ]. Three studies involving GCs looked at experience with patients inquiring about DTC-GT, with 40% to 94% of GCs having encountered questions related to DTC-GT results review [ 26 , 30 , 32 ]. Conversely, an earlier study reported that only about one quarter of GCs had previous experience with a patient asking about DTC-GT results [ 32 ].…”