Breast Surgeons Essential for Effective Genetic Testing

Pat Whitworth, MD

It is imperative that surgeons remain involved in genetic counseling to meet the immense unmet need that exists for patients with breast cancer, given a shortage of available genetic counselors, according to Pat Whitworth, MD, at the 2017 Miami Breast Cancer Conference.

“Surgeons can provide genetic counseling. They do already provide genetic counseling. And they must provide genetic counseling,” said Whitworth, a breast surgical oncologist and director of the Nashville Breast Center. “The genetic counselors out there can't possibly handle all this. We all have to do it, and we all have to keep up.”

In most cases, surgeons are already effectively conducting genetic testing and counseling, Whitworth noted, and they should be allowed to continue with this practice, to improve low genetic testing rates. “Surgeons are used to doing this,” he said. “They understand that a variant of unknown significant (VUS) is literally clinically meaningless to any given patient. No action should ever be taken based on a VUS, in any case, at any time.”

According to a survey conducted by the American Society of Breast Surgeons, 54% of surgeons are currently ordering genetic tests, followed by a genetic counselor in 35.1% of cases. Furthermore, surgeons are collecting 63.3% of all ≥3 generation pedigrees and they are providing genetic counseling before and after BRCA testing in 51.6% of cases.

“Failure to utilize the expertise these doctors already have is going to results in a delay in needed testing, especially for a patient who just got diagnosed with breast cancer,” Whitworth said. “Phone consultation may serve as an additional barrier, if the counseling is immediately available to that patient by that doctor in that office.”

Genetic testing is broadly underutilized, with BRCA mutations identified in just 5% to 6% of the 220,000 unaffected carriers. Furthermore, of those with breast cancer with a deleterious BRCA mutation, just 30% were detected, illustrating a need for enhancing genetic testing.

“This is a public health failure. It's a real disaster and it is a failure of our system to get to these patients and give them the care they need,” Whitworth said. “The patients we've seen in our offices, with breast cancer, we've identified less than a third of those patients. This is an urgent problem and a gigantic unmet need.”

In general, 10.7% of all breast cancer patients have a deleterious mutation, according to a 25-gene panel. In this study, 6.1% of patients had a BRCA1/2 mutation, and predicting these patients fell within standard parameters, such as Ashkenazi ancestry; however, 4.6% of patients had a non-BRCA deleterious alteration, and factors predicting these mutations could not be identified.

“There are factors that are very good at predicting BRCA mutations, but they are not good at all at predicting mutations in these moderately penetrant genes,” Whitworth noted. “The guidelines will either go away or they're going to need to change.”

Payers represent an obstacle to genetic testing for surgeons, he added. Specifically, policy changes made by a handful of large payers to require that genetic counselors order tests led to a dramatic increase in test cancellation rates.

In those deemed eligible for testing by NCCN guidelines, the pre-policy cancellation rate was 9.5% versus 37.7% post-policy (P <.001). Cancellations increased in those with a family history (5% to 16%) and those with a personal history of ovarian cancer (6% to 30%). The positive test rate remained consistent, suggesting patient selection was not changed or optimized. Those without these policies did not have a change in cancellation rates during the same timeframe.

“This policy that was intended to improve care actually had the opposite effect—it harmed patients. It should be discontinued immediately,” Whitworth concluded.

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