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MammaPrint is a genomic test that evaluates the activity of 70 genes to determine risk of breast cancer recurrence and to indicate possible benefit from chemotherapy.

You may hear MammaPrint called a prognostic test, which means it’s a test that predicts your likelihood of experiencing a particular medical event. Prognostic tests are different than diagnostic tests, which show whether you have a medical condition. Prognostic test results showing a high likelihood of distant recurrence do not guarantee that you’ll have a distant recurrence—but they can help you and your care team make treatment decisions.

MammaPrint is performed using tumor tissue taken during a biopsy or surgery. The National Comprehensive Cancer Network (NCCN) and American Society of Clinical Oncology (ASCO) both support the use of MammaPrint in making decisions about post-surgery treatment and include it in their standard treatment guidelines.


Who is MammaPrint for?

MammaPrint is used to test tumors from women of any age who have been diagnosed with breast cancer that:

  • Is stage I, II, or IIIA
  • Has no lymph nodes involved, or one to three lymph nodes involved

MammaPrint is most commonly used in hormone receptor-positive, HER2-negative early-stage breast cancer with zero to three positive lymph nodes. In the MINDACT clinical trial, women with a MammaPrint low risk score had the best outcomes and did not benefit from chemotherapy. Women with MammaPrint high risk scores did benefit from chemotherapy. Talk to your physician about what your score means for you.

Right now, data are limited about how helpful genomic tests for early-stage breast cancer are in male breast cancer, but these tests can be considered.


How does MammaPrint work?

After a breast biopsy or surgery, the tumor tissue sample is sent to a lab for MammaPrint testing. The test looks at the activity of 70 genes and then assigns the tumor to one of four risk categories: Ultra Low, Low, High Risk 1, and High Risk 2.


What do MammaPrint results mean?

Your chance of distant recurrence within 10 years of diagnosis will be reported as a risk level based on the activity of the 70 genes analyzed by MammaPrint. Your doctor will consider your clinical risk (the size of the tumor, lymph node involvement, and other features of the cancer) as well as the MammaPrint score to help determine the breast treatment plan for you.

Possible results include:

  • Ultra Low Risk: MammaPrint Index of 0.355 or greater: People in this category have a low risk of distant recurrence and may safely avoid chemotherapy after surgery. Endocrine therapy is recommended, and your doctor will make a recommendation on how many years of therapy are appropriate. It’s important to know that while there is some data showing that people receiving an Ultra Low score may not need extended endocrine therapy, this also depends on the stage and other unique features of the cancer. Talk with your doctor about what’s right for your individual situation.
  • Low Risk: MammaPrint Index between 0 and 0.355: People in this category have a low risk of distant recurrence, and often do not need chemotherapy after surgery. Endocrine therapy is recommended (the duration at the discretion of your doctor).
  • High Risk 1: People in this category have a high risk of distant recurrence. Chemotherapy is typically recommended. Endocrine therapy is also recommended. Your doctor will talk with you about how long to take endocrine therapy.
  • High Risk 2: People in this category have a high risk of distant recurrence. Chemotherapy is typically recommended. Endocrine therapy is also recommended (duration at the discretion of your doctor).

Paying for MammaPrint

If you have private health insurance, your carrier may pay part or all of the cost of MammaPrint testing. It’s best to check your coverage before you have the test to avoid unexpected costs. Visit your insurance company’s online portal or call their customer service line to speak with someone about your plan’s coverage policy. Medicare and Medicaid may also provide some coverage of the cost of MammaPrint.

The maker of MammaPrint, Agendia, offers financial assistance programs for people who meet certain eligibility requirements. Visit their financial support page to contact their support team and learn more.

For more information on financial assistance for breast cancer testing and treatment, visit our Financial assistance page.


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Reviewed and updated: June 5, 2024

Reviewed by: Laura Huppert, MD


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