Treatment Types

Understanding the Oncotype DX® Test

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Your doctor may use a test called Oncotype DX^®, performed on tumor cells, to help guide your treatment plan. It looks at how likely the cancer is to return and whether chemotherapy is likely to help.

Because Oncotype DX^® is designed for early-stage breast cancer, it isn’t part of care planning for metastatic breast cancer. If you have MBC, please skip to the next section.

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What is Oncotype DX^®?

Oncotype DX^® is a tumor profiling test used for early-stage breast cancers that are estrogen receptor-positive (ER-positive), and HER2-negative. It helps your care team decide whether adding chemotherapy to endocrine therapy could be beneficial.

Tumor profiling tests look at the genes inside cancer cells—specifically, how those genes are behaving. These genes are part of the tumor, not your healthy cells. By studying a sample of tumor tissue (usually taken during a biopsy or surgery), doctors can learn more about how likely the cancer is to return and how it might respond to chemo. You may also hear this type of testing called genomic testing, molecular profiling, or genetic signature testing.

Oncotype DX^® is the most widely used tumor profiling test in the U.S. for breast cancer. It analyzes the activity of 21 specific genes in a tumor sample. The results are combined with other information—like tumor size and lymph node status—to better understand your risk and guide treatment planning.

Oncotype DX^® may be used for early-stage breast cancers that meet all of the following:

Cancer is ER-positive and will be treated with endocrine therapy
Cancer is HER2-negative
Cancer has not spread to lymph nodes, or has spread to just 1–3 nodes

There are other genomic profiling tests that may be used instead of Oncotype DX^®, such as Prosigna^®, MammaPrint^®, or EndoPredict^®.

What Your Oncotype DX^® Score Means

If your care team recommends Oncotype DX^®, your oncologist will explain the results and how they may influence your treatment plan. Your score falls on a scale from 0 to 100 and can be interpreted differently depending on your age, menopausal status, and whether cancer is in your lymph nodes.

For People Age 50 or Younger With No Cancer in the Lymph Nodes:

Score 0–15:

Low risk of recurrence. Most people in this range do well with endocrine therapy alone and are not likely to benefit from chemotherapy.

Score 16–25:

Intermediate risk. Some people in this group may benefit from adding chemotherapy. Your doctor can help you weigh the pros and cons.

Score 26–100:

Higher risk of recurrence. Chemotherapy is more likely to provide a meaningful benefit in reducing the chance of the cancer coming back.

For Those Age 50 or Younger With Cancer in the Lymph Nodes:

Score 0–25:

Lower risk of recurrence, but chemo may still offer some benefit.

Ovarian suppression along with endocrine therapy (such as tamoxifen or an aromatase inhibitor) will likely be included in your treatment plan.

Score 26–100:

Higher risk of recurrence. Chemotherapy is more likely to be recommended in combination with endocrine therapy to lower the risk of the cancer returning.

Ovarian suppression along with endocrine therapy (such as tamoxifen or an aromatase inhibitor) will likely be included in your treatment plan.