All individuals diagnosed with breast cancer should undergo genetic testing with a multigene panel, according to new recommendations from American Society of Breast Surgeons.
“I am excited by our new guidelines and look forward to the day when [National Comprehensive Cancer Network] updates its guidelines, also. The exciting new data demonstrated that about half of patients with breast cancer have clinically actionable mutations that are being missed when genetic testing is restricted to patients meeting current NCCN guidelines,” Walton Taylor, MD, president of American Society of Breast Surgeons, said in a press release. “As genetic testing expands, it is important to choose the lab carefully, making sure they provide quality testing with accurate results and appropriate follow-up.”
The new guidelines are based on a study published in Journal of Clinical Oncology. Researchers in that study analyzed data for 959 patients with breast cancer and found that only 49.95% met NCCN criteria.
Overall, 8.65% of the patients had a pathogenic and/or likely pathogenic variant. Results showed 9.39% of the patients who met NCCN guidelines and 7.9% of patients who did not meet the guidelines had a pathogenic and/or likely pathogenic variant.
About 330,000 people are diagnosed with breast cancer annually in the U.S., and 10% of those cases are likely due to inherited mutations, according to American Cancer Society. Less than 10% of BRCA1/BRCA2 carriers have been identified. Further, as many as 80% of those who are at risk have not undergone genetic testing, partly because they do not meet the current testing guidelines’ criteria for family history.
The American Society of Breast Surgeons recommendations state that all patients with breast cancer should be offered genetic testing that includes BRCA1, BRCA2 and PALB2.
In addition, the recommendations state that patients with previous genetic testing may benefit from updated testing, as genetic testing done before 2014 likely did not test for PALB2 or other relevant mutations.
The guidelines maintain that patients without a history of breast cancer should undergo genetic testing if they meet NCCN guidelines for doing so.
Also, variants of uncertain significance are DNA sequences that are not clinically actionable, a result that should be deemed inconclusive.
The guidelines recommend that breast surgeons, genetic counselors and other professionals with expertise in genetic testing provide patient education and counseling regarding genetic testing. Genetic counselors should be employed when the rest are complex.
Myriad Genetics, whose products include the myRisk Hereditary Cancer test, announced its support of the new American Society of Breast Surgeons guidelines in a press release.
“We applaud the [American Society of Breast Surgeons] for recognizing important advances in scientific knowledge, and for recommending genetic testing for all people with breast cancer,” Johnathan Lancaster, MD, PhD, chief medical officer of Myriad, said in the release. “The valuable information provided by genetic testing enhances physicians’ ability to select appropriate precision treatments, personalize care for patients and their families and improve health outcomes.” – by John DeRosier
American Society of Breast Surgeons. Consensus Guideline on Genetic Testing for Hereditary Breast Cancer. Available at: www.breastsurgeons.org/about/statements/PDF_Statements/Hereditary_Genetic_Testing_Patients_With_Without_Breast_Cancer.pdf. Accessed on Feb. 15, 2019.
Beitsch PD, et al. J Clin Oncol. 2018;doi:10.1200/JCO.18.01631.