A thorough family history is the foundation of precision medicine, according to the 2015 president of the National Society of Genetic Counselors.
Physicians have good reason to feel overwhelmed by the growing num­ber of genetic tests available for their consideration, said Joy Larsen Haidle, MS, CGC, the 2015 president of the National Society of Genetic Counselors (NSGC).
On a typical day, 10 new tests enter the market and begin competing for attention. That’s a lot to absorb by any standard, but it’s particularly daunting for professionals who are so busy they often cannot perform the most basic step in personalizing treatment: getting a thorough family history from each patient. Fortunately, Larsen Haidle told the audience at the 4th annual meeting of Patient-Centered Oncology Care, ge­netic counselors can help doctors take full advantage of new discoveries while cutting wasteful expenditures. Coun­selors perform a wide variety of ser­vices, but the most important may be figuring out which patients should get which genetic tests and which patients shouldn’t get any tests at all—a process that starts with the documentation of family history.
“Family history, to me, is the low-hanging fruit and is the core founda­tion of precision medicine,” she said, emphasizing the need for a pedigree that stretches back 3 to 4 generations. “As a genetic counselor, when I’m talk­ing about risk assessment, really all I’m referring to is we’re reviewing that pat­tern of cancers that are in the family to determine the likelihood that there is an inherited risk factor that’s contrib­uting to what we’re seeing. We need to develop a differential gene list so that when we’re trying to select among the panel tests and things that are avail­able, we need to make sure that any test that’s selected has all of the genes on the differential, and then select the most appropriate person to do the test­ing. It may not be the person that’s sit­ting right in front of me, it may be actu­ally a relative instead.”
In many cases, these thorough fam­ily histories find there’s no need for ge­netic testing. Larsen Haidle showed in­surance company data indicating that requirements for genetic counseling can reduce the number of inappropriate genetic tests from more than a quarter of all tests performed (which appears to be a rough approximation of the current norm) to well under 5% of all tests. She also cited the experience at ARUP Labo­ratories in Salt Lake City, which brought in genetic counselors to review the or­ders its employees received for genetic testing. They found some sort of error in 26% of the orders and saved $720,000 a year by canceling needless test orders and fixing faulty orders.
Counselors can also improve health outcomes by increasing the percentage of patients who get referred for genetic tests that they really do need, said Lars­en Haidle, who cited several studies that indicate many patients slip through the cracks. A study of 684 high-risk women found that 90% of the women discussed their family history with providers, but only 20% of the women were referred for the sort of genetic testing their his­tory justified. Counselors are far more likely to make the proper referrals, said Larsen Haidle, who then turned to re­search on patient adherence.
“When it comes to the uptake of risk-management strategies for individuals who have hereditary breast and ovarian cancer, they had a higher likelihood of being consistent and following through on those strategies after meeting with a genetic professional,” she said. “In­creased genetic counseling led to a high­er rate of having that same information communicated to the rest of the family.”
Such benefits may explain why the demand for genetic counseling has grown quickly. The total number of counselors has grown 88% since 2006, and productivity per counselor has grown significantly. Still, Larsen Haidle argued, many doctors could be taking far more advantage of the services that counselors can offer their patients.
“We know that the current system is not working, with 30% of the tests not being ordered appropriately,” she said. “It really is imperative that all of us are working together to do a better job.”