Patients must work with their healthcare team to interpret direct-to-consumer genetic test results alongside clinical context and family histories, Susan M. Domchek, MD, executive director of the Philadelphia-based Basser Center for BRCA at the University of Pennsylvania, wrote in an op-ed for STAT.
In early March, the FDA authorized 23andMe's direct-to-consumer genetic test that reports three mutations in the BRCA1 and BRCA2 genes, which are linked to breast cancer. Dr. Domchek, a medical oncologist specializing in the management of inherited cancer, wrote identifying the BRCA mutation can be "life-altering" for patients.
Physicians at Penn Medicine's Abramson Cancer Center tend to set aside an hour for the initial discussion, with additional follow-up visits. However, patients who receive genetic test results through direct-to-consumer services don't tend to benefit from access to these services.
"I help individuals understand their cancer risks along with strategies for cancer prevention and early detection," she wrote. "For most people, this is a complex and stressful conversation."
The lack of emphasis on physician interpretation can be harmful for patients, because "there's more to breast and ovarian cancer risk than BRCA1 and BRCA2," according to Dr. Domchek. She noted genetic tests ordered by physicians evaluate up to 30 genes. Even within BRCA1 and BRCA2, there are thousands of mutations, of which 23andMe only tests for three, she wrote.
In addition, family history plays a key role in determining a patient's care plan. A patient with a significant family history of cancer may need to schedule enhanced screenings, despite not having a BRCA mutation.
"Genetic testing can be lifesaving, but it must come with all the facts — which are mounting by the day — and appropriate professional support to help individuals live and plan for the best chance of a healthy life, no matter what the results reveal," Dr. Domchek wrote. "That's something a mail-order kit just can't do."
To access Dr. Domchek's op-ed, click here.