Multigene Testing Recommended for Those Predisposed to Cancer

Many people who test negative for BRCA1 and BRCA2 harbor other harmful genetic mutations.

Many people who test negative for BRCA1 and BRCA2 harbor other harmful genetic mutations.

A new approach to testing for genetic mutations may be needed for many patients genetically predisposed, a recent study indicates.

Published in JAMA Oncology, the study noted that multigene testing of women who don’t carry the BRCA1 and BRCA2 mutations found that some may carry other harmful genetic mutations. Among these mutations are common to moderate-risk breast and ovarian cancer genes and Lynch syndrome genes, which increase the risk of ovarian cancer.

Multigene panel genetic testing are increasingly used in patients evaluated for a predisposition to hereditary breast and ovarian cancer. With utilization of these tests on the rise, researchers are concerned as many of the genes tested are low- to moderate-risk genes. Consensus management guidelines for these genes have yet to be introduced or were introduced recently, according to the study.

For the current study, researchers sought to evaluate how frequently multigene panel testing can identify mutations in need of clinical action among women who lack BRCA1 and BRCA2 mutations.

The study included 1046 women who underwent multigene panel testing. Among these women, 3.8% were negative for BRCA1 and BRCA2, but had harmful mutations in other moderate-risk genes.

An additional 23 women were included in the clinical management analysis of the study, which found that of 63 women testing positive for mutations, 33 women would be considered for disease-specific additional screening and additional preventative measures.

"Multigene panel testing for patients with suspected HBOC risk identifies substantially more individuals with relevant cancer risk gene mutations than does BRCA1/2 testing alone,” the researchers wrote. “Identifying such mutations is likely to change management for the majority of these individuals and their families in the near term, and in the long term should lead to development of effective management guidelines and improved outcomes for at-risk individuals.”