What are the benefits of using genomic testing for breast cancer?

From the Guidelines

Genomic breast cancer testing is highly recommended for personalized treatment planning, as it helps avoid unnecessary chemotherapy and its side effects, while ensuring those who would benefit receive appropriate treatment. The use of genomic assays, such as Oncotype DX, MammaPrint, and EndoPredict, has been shown to provide important prognostic and predictive information, allowing for more precise and effective treatment strategies tailored to each patient's specific cancer characteristics 1. These tests analyze the genetic makeup of a patient's tumor to predict how aggressive the cancer might be and how likely it will respond to specific treatments. For example, a low Oncotype DX score (0-25) might indicate that hormonal therapy alone is sufficient, while a higher score suggests adding chemotherapy would be advantageous.

Benefits of Genomic Testing

• Helps avoid unnecessary chemotherapy and its side effects
• Ensures those who would benefit receive appropriate treatment
• Provides prognostic information about recurrence risk, aiding in making informed decisions about treatment intensity
• Allows for more precise and effective treatment strategies tailored to each patient's specific cancer characteristics

According to the most recent guidelines, routine genomic signature testing is recommended for ER positive, HER2 negative early stage breast cancer, with 100% of panelists favoring this approach 1. This approach has been shown to improve patient outcomes, reduce morbidity and mortality, and enhance quality of life. The use of genomic testing has become a standard of care in breast cancer treatment, and its benefits are well-established in the medical literature.

Key Considerations

• Genomic testing should be used to guide treatment decisions, rather than relying solely on clinical risk assessment
• The choice of genomic assay should be based on the individual patient's characteristics and the specific assay's clinical utility
• Clinicians should be cautious not to order multiple assays, as this is not recommended and may not provide additional benefit 1.

From the Research

Benefits of Genomic Breast Cancer Testing

• The use of genomic tests can provide important prognostic information, such as the risk for recurrence, and in some cases predictive information, such as the benefit of chemotherapy or extended adjuvant endocrine therapy 2, 3.
• Genomic testing can help identify patients with hormone receptor-positive breast cancer who do not require the addition of chemotherapy, reducing unnecessary treatment and side effects 3, 4.
• Genomic assays can aid in chemotherapy recommendations and predict the benefit from prolonged endocrine therapy, allowing for more personalized and accurate treatment decisions 3, 5.
• The use of genomic testing can help guide treatment decisions for early-stage breast cancer patients, improving outcomes and reducing the risk of recurrence 2, 6.

Types of Genomic Tests

• Several commercially available genomic tests are available, including Oncotype DX, MammaPrint, RecurIndex, PAM50, and EndoPredict, each with its own strengths and limitations 5, 6.
• These tests differ in the types of information they provide and the patient populations and clinical trials that were conducted to validate them 2, 6.

Clinical Utility of Genomic Testing

• Genomic testing has become an essential tool in the management of early breast cancer, offering crucial information for risk stratification and guiding adjuvant treatment strategies 6.
• The American Society of Clinical Oncology (ASCO) guidelines endorse the use of genomic assays, although some clinical contexts still lack definitive recommendations 6.
• The clinical utility of genomic assays is continually evolving, with ongoing research aimed at refining and optimizing their use in clinical practice 6.