Oncotype DX^® is a test that examines a woman's tumor tissue at a molecular level, and gives information about her individual disease. This information can help tailor treatment for her breast cancer. The Oncotype DX test is intended to be used for women with early-stage (Stage I or II), node-negative, estrogen receptor-positive (ER+) invasive breast cancer who will be treated with hormone therapy.

The Oncotype DX test determines how 21 specific genes — 16 genes linked to breast cancer and 5 control genes — are expressed (that is, their level of activity) within a tumor sample. The measurement of these genes is calculated to yield an individualized result called a Recurrence Score^®. The Recurrence Score result correlates with the likelihood that a woman's breast cancer will return (distant recurrence) and also indicates whether she is likely to benefit from chemotherapy.

Traditionally, doctors have used breast cancer characteristics such as tumor size, tumor grade and lymph node status to estimate how likely breast cancer is to come back, and to help determine treatment decisions. These characteristics are still helpful in choosing a course of treatment, but the additional information provided by the Oncotype DX test can help physicians and patients determine the appropriate treatment plan.

Oncotype DX has been included in the 2007 American Society of Clinical Oncology (ASCO) Clinical Guidelines on Use of Tumor Markers in Breast Cancer. This inclusion represents a significant step forward for the role of molecular diagnostics in breast cancer treatment planning. Read more here.

Oncotype DX has also been included in the National Comprehensive Cancer Network (NCCN) 2008 Breast Cancer Treatment Guidelines. This inclusion reinforces the significance of molecular diagnostics in breast cancer treatment planning and, in particular, the value of the individualized information provided by Oncotype DX. Read more here.

A recent study has shown that Oncotype DX may also be informative for post-menopausal women with node-positive, hormone receptor-positive (HR+) invasive breast cancer.

Is The Oncotype DX Test Right For Me?

If you are a woman who has recently been diagnosed with Stage I or II, node-negative, estrogen receptor-positive breast cancer, or if you are post-menopausal and have recently been diagnosed with node-positive, estrogen receptor-positive breast cancer, the Oncotype DX test may be appropriate for you. However, the decision to use the Oncotype DX test is one that you and your doctor should discuss and make together.