Direct-to-consumer genetic testing for cancer predisposition can have ‘pitfalls’
Key takeaways:
- Direct-to-consumer germline testing for cancer predisposition without oversight and guidance can cause anxiety, financial distress or other harms.
- People who undergo testing should receive genetic counseling.
Genomic cancer predisposition tests should be done with professional counseling, and the FDA should implement safeguards for direct-to-consumer products, according to a medical oncologist with expertise in cancer genetics.
Wafik S. El-Deiry, MD, PhD, FACP, director of Legorreta Cancer Center and associate dean of oncologic sciences at Warren Alpert Medical School at Brown University, co-authored an editorial published in Oncotarget that examined numerous issues with direct-to-consumer genetic testing. They include psychological and financial implications, misinterpretation of results, and the potential for data to fall through the cracks.
“This isn’t as simple as just sending in a test and getting a result,” El-Deiry, a Healio | HemOnc Today Editorial Board member, said in an interview. “It’s a complicated area with implications. It needs to be managed with careful oversight to avoid ultimate harms.”
Background
In 2023, the FDA approved marketing authorization for the Invitae Common Hereditary Cancers Panel.
The test — which can be sold directly to consumers — evaluates 48 different genes associated with various cancer types, including breast cancer, ovarian cancer, gastric cancer, Li-Fraumeni Syndrome and more.
In its approval, the FDA wrote, “Patients should speak with a health care professional, such as a genetic counselor, to discuss any personal/family history of cancer, as such information can be helpful in interpreting test results. Importantly, this test is not intended to identify or evaluate all known genes that can provide insight into predisposition for cancer.”
However, no oversight exists to ensure individuals follow-up on those results.
Issues with direct-to-consumer testing
El-Deiry outlined multiple issues that could arise from direct-to-consumer genomic testing. Many of them are rooted in the belief that screening the general population is unnecessary, he said.
“It’s said in the field that your greatest yield is actually to do the test on the person who’s developed the cancer,” El-Deiry said. “Then you have a test for all the other family members.”
If someone in the general population orders a test without any risk factors, they could experience multiple hardships, according to El-Deiry.
They can include anxiety over or misinterpreting the results, or not understanding their implications. Insurance may not cover the costs, increasing financial stress. Or, a person could receive a noteworthy result but not relay that information to a health care professional, meaning it will be omitted from their medical record.
“Part of what counseling gets at is, do you really want to know?” El-Deiry said. “And if you really want to know, what are the limitations of the test? What’s going to be done about the results? There’s also interpretation of the results. Experts in the field are there because of their expertise. There are variants that appear on test results that in 2023 maybe were not recognized as disease causing, but a year [or] 2 years later, there’s more literature that implicates them and now the significance is different. Without being plugged into the health care system, those fall through the cracks.
“I have heard genetic counselors who I respect talk about this sort of thing — that it keeps them up at night worrying about the changing knowledge,” he added.
Critics of El-Deiry have told him he’s being too “paternalistic.”
“[I’ve been told], ‘You’re interfering with people’s freedoms and constitutional rights,’” he said. “I disagree that this is paternalistic. I think there are issues that need to be addressed by regulators and some safeguards.”
‘Continue to evolve’
El-Deiry does not oppose germline testing.
“Of course there are great benefits in knowing risk with available tests,” he said. “If you have a cancer-causing allele in your germline that’s been inherited, and you find out the test result is negative, that’s a huge relief. It’s going to impact your life. You don’t have to do a lot of other medical screenings and interventions different from the general population, whereas, if it’s positive, you really do.
“People should also be aware that we don’t know all the genes that predispose to cancer in the germline,” he added. “A negative test does not mean you don’t have risk for developing cancer.”
Individuals who already have cancer or are at high risk for developing cancer are likely already being tested or discussing genomic testing with health care professionals.
For direct-to-consumer tests, El-Deiry wants assurances or guidelines that emphasize the need for expert counseling.
“The concern rises to a level above simply being recommended,” he said. “I am not sure that the pitfalls are known to consumers.”
National Comprehensive Cancer Network (NCCN) released guidelines for patients regarding genetic testing in January.
The guidelines describe what genetic testing is and discuss the process, testing criteria, costs, impact on family and more. They also recommend following-up with a genetics professional.
“While the NCCN guidelines state that ideally a health care professional trained in cancer genetics — as well as other experts — will be involved at each stage, the guidelines do not go through some issues with direct-to-consumer tests,” El-Deiry said. “The guidelines do recommend that if there is a positive result, individuals should discuss those results with a health care provider. They do mention that this may lead to having other tests such as a confirmatory genetic test.
“The NCCN guidelines further state that more comprehensive at-home tests are available through companies like Invitae and Color Genomics,” he added. “While these typically include the services of a genetic counselor, they often provide only limited opportunity to discuss and understand the significance of a gene test result.”
El-Deiry noted some other “pitfalls” did not get mentioned.
“This needs to continue to evolve,” he said. “There needs to be clear guidance, especially in light of what could happen, theoretically, even if it’s rare. It is important for anyone who gets these direct-to-consumer tests to have a clear path to getting that information into the record, to the attention of the physicians.”
References:
- El-Deiry WS, et al. Oncotarget. 2024;doi:10.18632/oncotarget.28677.
- FDA grants first marketing authorization for a DNA test to assess predisposition for dozens of cancer types (press release). Available at: https://www.fda.gov/news-events/press-announcements/fda-grants-first-marketing-authorization-dna-test-assess-predisposition-dozens-cancer-types. Published Sept. 29, 2023. Accessed Jan. 31, 2025.
- NCCN. Genetic testing for hereditary breast, ovarian, pancreatic, and prostate cancers. Available at: https://www.nccn.org/patients/guidelines/content/PDF/genetics-patient.pdf. Published: Jan. 16, 2025. Accessed: Jan. 31, 2025.
For more information:
Wafik S. El-Deiry, MD, PhD, FACP, can be reached at wafik_el-deiry@brown.edu.
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