Tumor profiling tests look at the genes inside cancer cells, which are different from normal cells.

A sample of cancer cells is removed during a biopsy or breast cancer surgery to better understand how the cancer may behave. They can help predict whether the cancer is likely to spread to other parts of the body, or in some cases, help guide treatment decisions.

Oncotype DX® is the most common tumor profiling test used in the U.S. and the only one used in breast cancer staging today. It can be included as a part of staging for some early-stage, estrogen receptor-positive, HER2-negative breast cancers.

Oncotype DX® can help determine whether chemotherapy is needed in addition to hormone therapy. So, if the test results show a low risk of cancer spreading to other organs in the future, then chemotherapy may not be needed, and hormone therapy alone is standard of care.

MammaPrint® is another tumor profiling test that also helps estimate the risk of cancer spreading and whether chemotherapy may be beneficial.

Talk with your doctor about whether tumor profiling might be helpful in guiding your treatment plan.

For more information, visit the Tumor Profiling page in the Treatment section of komen.org.