Relying only on BRCA gene tests may miss nearly half of people who carry a hereditary risk for cancer, according to a new study. Researchers found that standard BRCA1 and BRCA2 testing failed to detect 42% of individuals who had other high risk gene mutations linked to breast, ovarian, and other cancers. The findings suggest that broader multigene panel testing could offer a more complete picture of a person’s inherited cancer risk.

Key Takeaways

  • Standard BRCA tests alone miss 42% of hereditary cancer risk cases, according to the study.
  • Broader multigene panel testing can identify mutations in other cancer related genes beyond BRCA1 and BRCA2.
  • Current guidelines may need updating to recommend broader testing for more patients.
  • Identifying hidden mutations could help guide prevention and early detection strategies.

Study Details

The study, reported by Inside Precision Medicine, analyzed genetic data from a large group of individuals who underwent testing for hereditary cancer risk. Researchers compared results from standard BRCA1 and BRCA2 testing with results from comprehensive multigene panel tests that looked at a wider range of genes known to be associated with cancer risk.

They found that 42% of people who carried a pathogenic variant, or harmful mutation, in a cancer risk gene would have been missed if only BRCA testing was performed. Many of these individuals had mutations in genes such as PALB2, CHEK2, ATM, and others that are linked to increased risk for breast, ovarian, pancreatic, and prostate cancers.

Implications for Patients

For patients, these findings mean that a negative BRCA test does not rule out hereditary cancer risk. People with a strong family history of cancer or other risk factors may benefit from broader genetic testing. Identifying a mutation in a gene like PALB2 or ATM can lead to tailored screening recommendations, such as starting mammograms at an earlier age or adding MRI scans.

It can also inform decisions about preventive surgeries, such as mastectomy or oophorectomy, and guide family members who may also be at risk. The study authors argue that current testing guidelines, which often focus on BRCA testing first, may need to be revised to include multigene panels as a standard approach.

What This Means for Clinical Practice

The study highlights a growing consensus among genetic specialists that multigene panel testing should replace sequential single gene testing. Instead of testing for BRCA first and then ordering additional tests if results are negative, experts suggest performing a comprehensive panel upfront. This approach can save time, reduce the need for multiple blood draws, and provide more complete information from the start.

However, broader testing also brings challenges. It can uncover variants of uncertain significance, meaning mutations whose impact on cancer risk is not yet known. This can cause anxiety for patients and require follow up testing. Genetic counseling is essential to help patients understand their results and make informed decisions.

Frequently Asked Questions

Why do BRCA tests miss so many hereditary cancer risks?

BRCA tests only look for mutations in the BRCA1 and BRCA2 genes. There are many other genes linked to hereditary cancer risk, such as PALB2, CHEK2, ATM, and others. Standard BRCA testing does not detect mutations in these genes, so people who carry them are missed unless broader testing is done.

Who should consider multigene panel testing instead of BRCA testing alone?

People with a strong personal or family history of cancer, especially breast, ovarian, pancreatic, or prostate cancer, may benefit from multigene panel testing. Those who have had a negative BRCA test but still have concerning risk factors should discuss broader testing with a genetic counselor.

Are there any downsides to broader genetic testing?

Broader testing can sometimes find variants of uncertain significance, which are genetic changes that doctors do not yet fully understand. These results can cause worry and may require additional testing or family studies. Genetic counseling is important to help interpret results and guide next steps.

This is an original report by Vital Signs Today, informed by reporting from Google News. Read the original source.

This article is for information only and is not medical advice. See our Medical Disclaimer.