First, take a deep breath. Many of us have now experienced this phenomenon. Five years ago, you may have told this patient that DTC test results are not “real” genetic test results, and that he should ignore them. But we now know that up to 60% of test results derived from raw data reads are accurate, and that the accuracy is much higher for the three common Jewish BRCA mutations that 23andMe now has FDA clearance to return directly to consumers. We, as healthcare providers, can no longer afford to ignore these test results, as they can yield meaningful results for the patient and his/her entire family.
But it’s difficult, if not impossible, for a busy oncology professional to stay on top of all of the emerging companies that are offering DTC genetic testing. In addition, a few DTC companies can return some results directly to patients (23andMe returns the 3 Jewish BRCA mutations), some DTC companies are considered “clinical grade” (like Color genetics), and many will return raw data files to patients which they can upload to 3rd party companies (e.g. Promethease) that match their variants to relevant literature in the field. Each of these result types has its own limitations and nuances, and requires different counseling. So how should an oncology professional handle this mash of genetic information?
- Acknowledge that getting genetic test results back can be confusing, and sometimes frightening.
- Underscore that most DTC genetic testing is not as thorough, complete, or accurate as medical-grade testing, and that there are both false-negatives and false-positives because of these limitations. No conclusions should be drawn based solely on DTC genetic testing alone.
- Suggest that the patient speak to a certified genetic counselor who can review both the DTC test results and the personal and family history in detail, to determine what confirmatory testing, or broader testing, is needed. If you do not have a genetic counselor on-site or nearby, or if the wait-time is longer than desired, there are also multiple phone genetic counseling services that can speak to your patients. A few that specialize in DTC counseling include:
- Consider offering the patient an online resource, such as MyGeneCounsel.com, where they can purchase a low-cost report that will help him/her better understand these results.
- Follow up with the patient 3 months out to see if genetic counseling and confirmatory testing was completed. If not, encourage the patient to pursue this channel.
- Once the patient has been seen by a genetics professional, help them implement the suggested medical management plan.
More than 15 million consumers have now had DTC genetic testing and it is estimated that 100 million will have such testing by 2021.1 Between DTC genetic testing, large population studies, and employer-initiated testing program, the majority of our patients will come in to appointments with test results in hand within the next decade. Some of these test results will be inaccurate, and others will provide accurate insights into hereditary cancer risk or pharmacogenetic information that will be critical in your management of the patient and the entire family. Oncology nurses will be critical in helping patients may sense of their genetic test results.
- Khan R, Mittelman D. Consumer genomics will change your life, whether you get tested or not. Genome Biology 2018;19:120. doi: 10.1186/s13059-018-1506-1.