Genomic testing in early-stage breast cancer

In early-stage breast cancer, genomic tests look at gene expression in cancer cells. Some doctors explain gene expression as a gene being “turned on” or activated.

Some types of genomic tests can predict the risk of recurrence in early-stage breast cancer. These tests look at the level of activity in specific groups of genes in cancer cells to determine whether a cancer is likely to recur and how it might respond to treatment. You may hear other names for these tests, such as genomic assays or gene expression tests. Genomic tests are one of many kinds of tumor biomarker tests.

It’s important to know that right now, data are limited on how helpful genomic tests for early-stage breast cancer are in planning treatment for male breast cancer. Some research suggests that the Oncotype DX Recurrence Score may provide information on the risk of recurrence for men.

For those with metastatic breast cancer, instead of the genomic tests described below, biomarker tests such as next-generation sequencing are used to inform treatment decisions. Learn more about biomarker tests here.

Genomic tests versus tests for inherited genetic mutations

Genomic tests for early-stage breast cancer are different than next-generation sequencing (NGS), which look for specific mutations. They’re also different than tests for inherited genetic mutations. There are differences in the way these tests are performed, the kinds of results they give, and how the results inform your care:

• Genomic tests used in early-stage breast cancer look at the activity of specific groups of genes in breast cancer cells to find out whether gene activity affects the risk of recurrence or potential response to certain treatments, such as chemotherapy or endocrine therapy. These tests are performed on tumor tissue samples.
• Next-generation sequencing (NGS) tests, mainly used in metastatic breast cancer, are a broader type of genomic test that look at a panel of genes in breast cancer cells to find out if the cancer cells have developed non-inherited mutations that can match the cancer to a specific treatment. Learn more on the biomarker testing page.
• Tests for inherited genetic mutations look for gene abnormalities that a parent may pass on to you. These tests can identify inherited mutations, such as BRCA1 and BRCA2, that can increase the risk of breast cancer and other cancers. Tests for inherited genetic mutations use a blood or saliva sample, or a swab from the inside of the cheek. Knowing if you carry an inherited breast cancer gene mutation can help your doctors understand more about your risk of recurrence and how breast cancer might respond to certain treatments if it does develop. To learn more, visit genetics and family risk.

Types of genomic tests for early-stage breast cancer

Below, we’ll walk you through the different genomic tests available for early-stage breast cancer.

Breast Cancer Index

The Breast Cancer Index test looks at expression of 11 genes in early-stage, hormone receptor-positive breast cancer with no cancer in the lymph nodes, or cancer in one to three lymph nodes. The test measures the risk of recurrence after you’ve completed five years of endocrine therapy to determine whether you should continue to take endocrine therapy for up to five more years.

Breast Cancer Index is available to women who:

• Were diagnosed with early-stage (stage I to IIIA), hormone receptor-positive breast cancer
• Are of any menopausal status (pre-, peri-, or post-)
• Have no cancer in the lymph nodes at diagnosis, or cancer in one to three lymph nodes at diagnosis
• Have no signs of cancer after treatment with five years of endocrine therapy

This test is performed on tumor tissue taken out during your original biopsy. Both the National Comprehensive Cancer Network (NCCN) and American Society of Clinical Oncology (ASCO) include Breast Cancer Index in their standard treatment guidelines.

EndoPredict

The EndoPredict test looks at expression of 12 genes to measure a woman’s risk of breast cancer recurring from diagnosis through 15 years post-treatment. The results are combined with other information about the cancer to help determine whether you need chemotherapy after surgery. If you’ve already had five years of treatment with endocrine therapy, the test results can help your doctor determine if you should continue for another five to 10 years.

EndoPredict is performed using tumor tissue taken during a biopsy or breast cancer surgery such as lumpectomy or mastectomy. NCCN and ASCO both support the use of EndoPredict in making decisions about post-surgery treatment and include it in their standard treatment guidelines.

EndoPredict can be used to test tumors from women who are postmenopausal or who are age 50 and over, and have:

• Been diagnosed with early-stage, hormone receptor-positive, HER2-negative breast cancer
• No lymph nodes involved, or have only one to three lymph nodes involved
• A biopsy tumor sample that has never been frozen

MammaPrint

The MammaPrint test looks at the expression of 70 genes to measure whether an early-stage breast cancer is at high risk or low risk of returning as metastatic breast cancer within 10 years of diagnosis. The results can help your doctors determine whether you need chemotherapy.

MammaPrint is performed using tumor tissue taken during a biopsy. NCCN and ASCO both support the use of MammaPrint in making decisions about post-surgery treatment and include MammaPrint in their standard treatment guidelines.

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

BluePrint

The BluePrint test evaluates expression of 80 genes to determine a breast cancer’s molecular subtype, a term that describes how breast cancer cells behave based on certain disease characteristics. Molecular subtype allows doctors and researchers to classify different breast cancers by their receptor status, grade, and behavior. Right now, a cancer’s molecular subtype alone does not guide treatment decisions. Your doctors will choose treatments by looking at the individual characteristics of the cancer cells—such as estrogen, progesterone, or HER2 receptors—that make up the molecular subtype.

BluePrint is an optional companion test to MammaPrint. If your doctor wants to know more about the behavior of the cancer cells, they can choose to order BluePrint at the same time they order MammaPrint. There are four possible molecular subtypes as defined by BluePrint:

• Luminal A-type
• Luminal B-type
• Basal-type (also called basal-like or triple-negative)
• HER2-type (also called HER2-enriched or HER2-positive)

To learn more about molecular subtypes, visit Molecular subtypes of breast cancer.

Oncotype DX Breast Recurrence and DCIS Score tests

The Oncotype DX Breast Recurrence Score test evaluates the expression of 21 genes to determine a person’s risk of invasive, early-stage hormone receptor-positive, HER2-negative breast cancer recurring within the next nine years, as well as how likely they are to benefit from treatment with chemotherapy. It is part of the standard treatment guidelines for the NCCN and ASCO.

Another test, the Oncotype DX Breast DCIS Score, is designed for people diagnosed with ductal carcinoma in situ (DCIS), sometimes called stage 0 breast cancer. This test measure’s a person’s 10-year risk of the cancer returning within the breast duct or spreading outside of the duct and becoming invasive.

Both Oncotype tests are performed on tumor tissue taken during a biopsy or breast surgery. For early-stage, invasive breast cancer, Recurrence Score results help your doctors determine if you need treatment with chemotherapy or can safely take endocrine therapy alone. For DCIS, the results help your doctors determine if you need radiation therapy.

The Oncotype DX Breast Recurrence test can be used to test tumor samples in women of any age who have:

• Hormone receptor-positive, HER2-negative early-stage breast cancer
• Breast cancer that is stage I, II, or IIIA

You may be eligible to get the Oncotype DX Breast DCIS Score test if you:

• Have been diagnosed with DCIS
• Have a tissue sample available from a biopsy or lumpectomy

ASCO includes Oncotype DX in their standard treatment guidelines for making decisions about chemotherapy and endocrine therapy. NCCN recommends Oncotype DX over other tests to determine the potential benefit of chemotherapy.

Prosigna

The Prosigna test looks the activity of 50 genes in breast tumor tissue to provide a Risk of Recurrence score that measures the risk of recurrence over the next 10 years. This ROR score is used to guide decisions about chemotherapy treatment.

Prosigna can also determine the breast cancer’s molecular subtype, a term that describes how breast cancer cells behave based on certain breast cancer cell characteristics, such as estrogen, progesterone, or HER2 receptors. Right now, a cancer’s molecular subtype alone does not guide treatment decisions. Your doctors will choose treatments by looking at the characteristics of the cancer cells that make up the molecular subtype.

Prosigna is included in the NCCN and ASCO standard treatment guidelines.

This test is for women who:

• Are postmenopausal
• Have hormone receptor-positive, HER2-negative, early-stage breast cancer that is stage I or II
• Have no cancer in the lymph nodes, or cancer in only one to three lymph nodes

Paying for genomic tests

Many private insurance companies will pay part or all of the cost of genomic tests. The best way to find out what your insurer will cover is by visiting their online member portal or by calling their customer service line. Contact information for both is usually listed on the back of your insurance card. Medicare programs also often cover these types of tests in some part.

The makers of these tests also sometimes offer patient assistance programs or financial assistance programs to help you cover the costs.

To learn more about paying for breast cancer treatment, visit Financial assistance.