BRCA TESTING

In a guideline update released today, the US Preventive Services Task Force (USPSTF) reaffirms its 2005 recommendation on risk assessment, genetic counseling, and testing for BRCA-related cancers.

The USPSTF recommends that primary care providers screen women who have family members with breast, ovarian, tubal, or peritoneal cancer to identify a family history that may be associated with an increased risk for mutations in the breast cancer susceptibility genes BRCA1 or BRCA2.

Women with positive screening results should receive genetic counseling and, if indicated after counseling, BRCA testing, the task force says. It recommends against routine genetic counseling or BRCA testing for women whose family history is not associated with an increased risk for mutations in theBRCA1 or BRCA2 genes.

The updated recommendation on BRCA-related cancer is "pretty similar to what we said before. It's a little more granular, but from the standpoint of a news story, it's not a big change," task force chair Virginia A. Moyer, MD, MPH, said in an interview with Medscape Medical News.

Results Rarely Clear-Cut

"In 2005, we said in a rather general way that women whose family history is associated with increased risk be referred for genetic counseling and evaluation for testing. Otherwise, don't do that," Dr. Moyer explained.

"We don't always say, 'do this, but don't do that.' But in this case, we do say, 'do this, but don't do that,' and the reason is that women who are not at increased risk are potentially going to be harmed by testing," Dr. Moyer said. "In fact, over 90% of women have absolutely no reason to be tested, and it would be a mistake for those women to be tested."

Dr. Moyer said it is important for clinicians to know that women may ask for the test under the mistaken assumption that the test comes back either positive or negative, but usually that is not the case.

"The test comes back with complex results that require interpretation; occasionally it's positive, and sometimes it's negative, but most of the time it's somewhere in the middle, and knowing how to interpret depends on family history and whether you have a lot of other information, and that's why a genetic counselor or someone with training in genetic counseling needs to be doing this," Dr. Moyer said.

The task force notes that since 2005, several family history risk stratification tools have been developed and validated for use in primary care practice to guide referral for BRCA genetic counseling. In general, the tools present a series of questions designed to elicit information about factors associated with an increased likelihood of BRCA mutations.

These tools are "clinically useful predictors of which women should be referred for genetic counseling," the task force says, with sensitivity estimated at higher than 85%. Each risk assessment tool has limitations, and the task force found insufficient evidence to recommend 1 tool over another.

The recommendation update on risk assessment, genetic counseling, and genetic testing for BRCA-related cancer in women was published online December 23 in the Annals of Internal Medicine and is also available on the USPSTF Web site.

Funding for the update was provided by the Agency for Healthcare Research and Quality (AHRQ). Disclosure forms for USPSTF members can be viewed on the journal's Web site.

Ann Intern Med. Published online December 23, 2013. Abstract