When should the Oncotype DX Breast Recurrence Score test be used?

The Oncotype DX Breast Recurrence Score test is for patients who have been recently diagnosed with invasive stage I, II, or IIIa breast cancer. In addition, the patient’s breast cancer needs to be estrogen-receptor positive (ER+) and HER2-negative (HER2-).

The Breast Recurrence Score test is performed on a post-surgery (lumpectomy or mastectomy) tumour sample or on a core biopsy. As a result, the test should be used after the original surgery or biopsy, but before treatment begins—since the test is intended to help guide treatment decisions. Learn more about how the Breast Recurrence Score test works.

What is the difference between genetic tests (e.g., BRCA 1 and BRCA 2) and genomic tests like the Oncotype DX test?

Genetic tests help people understand their risk for getting cancer. Genomic tests help people who have been diagnosed with cancer with their treatment planning. Once you have cancer, the activity of certain genes in your tumour tissue influences the behavior of your tumour, including how likely it is to grow and spread. The Oncotype DX Breast Recurrence Score test looks at these genes to help you and your doctor make decisions about your care.

What differentiates the anatomic stages of breast cancer? How does this affect my eligibility?

There are five different anatomic stages of breast cancer: 0, I, II, III, and IV. These stages tell you how much the cancer has grown and spread. For example, stage 0 cancer is an early form of non-invasive cancer that is contained in one place, while stage IV is cancer that has spread throughout the body. If you have stage I, II, or IIIa breast cancer, you may be eligible for the Oncotype DX Breast Recurrence Score test.

If you have ductal carcinoma in situ (DCIS), you have stage 0 (non-invasive) cancer. “In situ” means all of the cancer cells have not spread outside the milk duct. Only patients with DCIS are eligible for Oncotype DX Breast DCIS Score test.

Learn more about the anatomic stages of cancer.

What does it mean to be ER-positive or ER-negative?

Estrogen is one of the hormones in your body. It has many roles, such as triggering development of female characteristics and facilitating the reproductive process. In (and on) breast cells, there are “hormone receptors”—proteins that pick up estrogen signals that tell the cells to grow. They are called “estrogen receptors.”

If the cancer cells in your breast have estrogen receptors, they are called "ER-positive". ER-positive cancer cells (like normal breast cells) may receive signals from estrogen—so the cancer might respond to hormonal therapy. If the cancer cells don’t have estrogen receptors, they are classified as "ER-negative". With ER-negative cancer cells, hormonal treatment is unlikely to work, so your doctor will look for other options.

What does HER2 mean?

HER2 (human epidermal growth factor receptor 2) is a protein also appears on the surface of some breast cancer cells. HER2-positive breast cancers have a lot of HER2 proteins (“HER2 over-expression” or “HER2 amplification”). HER2-negative breast cancers have little or no HER2 proteins. Different treatments are considered depending on the HER2 status.

Only patients with HER2-negative (HER2-) status are eligible for the Oncotype DX Breast Recurrence Score test.

What does lymph node-negative mean?

You have many lymph nodes in your body. These are small organs that help remove unwanted particles such as bacteria and viruses from your body. If your tumour has not spread to nearby lymph nodes, your cancer will be classified as "lymph node-negative (N-)." If the cancer has been found in the lymph nodes, the cancer will be classified as "lymph node-positive (N+)."

Patients with N- breast cancer may be eligible for the Oncotype DX breast cancer test. Patients with N+, estrogen-receptor-positive (ER+) breast cancer may also be eligible for the test.