Karen Lu Discusses ASCO Study on MAGENTA, Genetic Counseling

Women who get genetic testing for hereditary breast and ovarian cancer are often advised to talk to a genetic counselor before and after they take the test, even if the result is negative for a mutation that would indicate a greater risk.

But results presented at the 2020 annual meeting of the American Society of Clinical Oncology this weekend suggests that an online educational video about genetic testing may be sufficient and that women don't need to speak with genetic counselor in the context of this type of testing.

“We were surprised by the findings,” said Karen H. Lu, the study's principal investigator and chair of the Department of Gynecologic Oncology and Reproductive Medicine at University of Texas MD Anderson Cancer Center in Houston, said in interview with Managed Healthcare Executive.®

“I would hate for anyone to say, ‘we don’t need genetic counselors, they are not necessary,’” Lu added. “I think what (we) need to do is use them in the most effective way possible.”

Lu and her colleagues presented findings from MAGENTA (Making GENetic Testing Accessible, NCT02993068), a four-arm study that included 3,111 women with a family history of hereditary breast and ovarian and another group of 711 women with a family member who had gotten a genetic test that came back positive for a risk-conferring mutation. 

Women enrolled in the trial watched an online educational video about genetic testing. Lu explained that women in the control arm of the study spoke with a genetic counselor by telephone before and after they took the genetic test, an at-home "spit kit" test that involves collecting saliva sample for DNA testing. (The Magenta study website blurbs it as “the study of genetic testing from your living room.)

Others arms of the study included genetic counseling only before the genetic test, only after, and no genetic counseling either before or after.

However, if the test was positive for a risk-conferring mutation, genetic counseling was given regardless of which arm of the study the woman was in. Among the participants who completed testing, 173 (7.2%) had a positive test.

The primary outcome was “cancer risk distress” at three months. Lu and her colleagues found cancer risk a distress measurement of women in the three groups with more limited genetic counseling-including the group that didn’t receive any counseling (provided that the result was negative)-was  noninferior to the group that received counseling before and after the test, which Lu described as the current standard of care.

Analysis of data on secondary endpoints such as anxiety, depression and “decisional regret” painted a similar picture of no difference among the four arms. Test completion was, though, highest in the no counseling arm (86.4%) and lowest in the control arm (60.6%).

Lu said genetic counselors provide “just a wonderful service” to patients but also that there aren’t enough of them, particularly as testing becomes more prevalent and instrumental in making treatment decisions. She said the most effective way to use counselors may be to focus their efforts on people who test positive for risk-conferring mutations and those with a strong family history.

The overarching concern is making genetic testing more accessible, so women at high risk are identified and monitored or treated early, said Lu. “As a whole [the Magenta results] really show that this type of testing-which is available commercially-can be used,” she said.