Are Multigene Tests Replacing BRCA Tests for Breast Cancer Risk?

New Generation Solutions for Hereditary Cancer Risk

Multigene testing is increasingly used in breast cancer diagnosis. Will these new generation tests replace BRCA testing? The answer could have major implications for women’s health. Research shows that multigene tests provide more information, but not every aspect of this approach is fully understood. This article discusses their advantages and disadvantages compared with BRCA tests.

Breast Cancer Risk: The Rise of Multigene Testing

Genetic testing for hereditary breast cancer has generally focused on BRCA mutations. Among women with breast cancer, multigene testing has increased while testing only for BRCA1 and BRCA2 mutations has decreased. This has not increased prophylactic mastectomy rates. Multigene panels provide clinically useful information. Compared with hereditary breast cancer tests assessing BRCA1 and BRCA2 alone, they yield approximately twice as much information .

New generation multigene tests also return results faster, meaning BRCA mutation assessment no longer has to wait until after surgery. 

A JAMA Oncology Study: Breast Cancer and Genetic Testing

Research by Dr. Allison W. Kurian and colleagues between 2013-2015 provides important data on genetic testing among women diagnosed with breast cancer. Key findings include:

• Participants and Period: More than 5.000 women with stage-0 to stage-2 breast cancer were examined during 2013-2015.
• Genetic Testing Rates:
  • Only one-quarter of women underwent any genetic testing.
  • This proportion remained stable over the two-year period.
• Increase in Multigene Panel Testing:
  • In the first half of 2013, 26% of those tested received a multigene panel test; by mid-2015, this rose to 66%.
  • Over the same period, the proportion receiving BRCA-only testing fell from 74% to 34 percent.
• Developments in Genetic Testing:
  • Genetic tests have become more comprehensive and less expensive.
  • This development has revealed a significant shortage in the genetic counseling workforce.
• Genetic Counseling and Hospital Needs:
  • More clinical genetic counselors are needed and should be incorporated into cancer care.
  • Hospitals must be able to provide timely genetic counseling to eligible patients.

This study highlights the importance of genetic testing in breast cancer diagnosis and treatment and identifies current gaps. Increasing use of multigene panels creates opportunities to use genetic testing more effectively in breast cancer care.

Conclusion: The Future of Multigene Testing

Multigene testing marks a new era in breast cancer diagnosis and treatment. Although these tests provide more comprehensive, faster results, adequate genetic counseling and suitable hospital systems must also be developed. Whether they will replace BRCA tests will become clearer through future research and developments. This change may affect patients and their families, making close monitoring of the impact of genetic testing important.

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Further Reading: What Are Multigene Tests?

Multigene tests are comprehensive tests used to diagnose a range of genetically associated diseases or conditions. Here are the details:

• Definition: Multigene tests examine genetic variation using a panel of multiple genes. They detect changes or mutations in genes’ DNA sequences.
• Applications:
  • Determining disease risk: They can identify the risk of diseases with a genetic predisposition, particularly cancer.
  • Guiding treatment decisions: Tailoring treatment to the disease type and its genetic characteristics.
  • Assessing relatives’ risk: Evaluating the risk of carrying hereditary diseases within a family.
• Technology: High-throughput sequencing technologies allow many genes to be analyzed simultaneously.
• Advantages:
  • Broad coverage: Multiple genes can be examined at once, assessing a wide spectrum of diseases.
  • Time and cost efficiency: A single test examines mutations in many genes, potentially saving time and money.
• Disadvantages:
  • Uncertain results: Genetic variants of uncertain clinical significance may be found.
  • Ethical and psychological issues: Results can raise ethical and psychological concerns for patients and relatives.
• Example Application—Breast Cancer: In breast cancer, multigene testing can create a broader genetic profile and assess risk more precisely than tests focusing solely on BRCA1 and BRCA2.

Multigene testing is a powerful tool in modern medicine for understanding and treating genetically based diseases. It enables personalized medicine and helps develop more effective treatments. However, its complexity and potential ethical issues require careful consideration of its use.