What is a Oncotype DX Test?

This Valuable Diagnostic Test Can Help Determine Your Treatment Plan

Nurse practitioner Joan Magit (cq,right) talks with patient Robertina Perez. Credit: David Bohrer / Contributor / Getty Images

Early detection of breast cancer saves lives and earlier diagnosis often means less strenuous treatments as well. But how would your oncologist know which treatments would really prevent the return of your cancer? The Oncotype DX is a valuable diagnostic test that helps you and your oncologist determine which treatment plan will be most effective in preventing cancer recurrence or help manage your disease.

 

Oncotype DX Diagnostic Test For Early Stage Breast Cancer

In order for this test to be administered, your doctor will evaluate if you are a candidate for this test by looking for these criteria: 

This test examines samples of your tumor tissue and rates it for a specific set of genes that can influence the possibility of recurrence within 10 years after your original diagnosis. This rating is called your recurrence score.

Breast Cancer Diagnostic Standards:

Your blood and tissue will be tested by several standards to determine your unique diagnosis. The results of these tests affect your treatment options. Tests are for:

All of these test results produce a diagnosis, but without genetic information, your risk of recurrence is difficult to determine.

Your genetic information, in addition to all of your test scores, gives a clearer picture of whether or not you need chemotherapy to prevent the return of your breast cancer.

Risk of Recurrence Based on Genetic Expression

Your recurrence score will be based on the genetic expression of 21 genes, 16 of which are cancer-related and 5 of which are for reference.

The genes are grouped by function: proliferation, invasion, hormone receptors (estrogen and progesterone) and growth factors. Each person's test results will be unique, but will fall into one of three categories:

  • Low risk
  • Intermediate risk
  • High risk

How Risk of Recurrence Affects Treatment Decisions:

Patients who have a low risk of recurrence may not need any chemotherapy and may be able to take hormone therapy as their follow-up treatment after surgery. If you are in the intermediate to high-risk categories, you may need chemotherapy as well as hormone therapy to further reduce your risk of recurrence. Many other factors like age, tumor grade and hormone receptor status will be considered before you decide on a treatment plan, but research has shown that results from the Oncotype DX test are a very strong predictor for recurrence.

Other Treatment Decision Decisions That Affect You

This test does not tell your doctor which type of chemotherapy drugs to use, whether or not you need Herceptin, or whether you will need radiation therapy.

Those decisions will be based on the results of other tests.

Covering the Cost of a Genetic Assay Test

Medicare and several private health insurance companies will help cover the cost of an Oncotype DX test. Check with your insurance provider to find out if you are covered for this test. To qualify for this test, you must have Stage 1 or Stage 2 node-negative, estrogen receptor-positive breast cancer. The test is analyzed and provided by Genomic Health and if you are uninsured or under-insured, you may want to contact them about financial assistance.

Sources:
"Cancer Diagnostics: Informing the Development of Tailored Cancer Therapy". National Cancer Institute. 2006. 

Genomic Health. About Oncotype DX. Information for Patients and Caregivers, 2008. 

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