What is the Oncotype DX^® test, and what makes it unique?

The Oncotype DX Breast Recurrence Score^® test has been developed for patients with early-stage HR+, HER2- breast cancer to:

• Precisely identify those patients who will and will not benefit from adjuvant chemotherapy
• Determine the magnitude of chemotherapy benefit
• Provide an individual’s risk of distant recurrence

Chemotherapy causes both short- and long-term side effects affecting current and future health, quality of life, family life and work life.^1–3The vast majority of patients with HR+, HER2- early-stage breast cancer do not benefit from adjuvant chemotherapy.⁴

Eligibility

Patients are eligible for the Breast Recurrence Score test if they are:

• Recently diagnosed with invasive breast cancer
• Medically eligible for chemotherapy

And the cancer is:

• Anatomic stage I, II, or IIIa
• Estrogen-receptor positive (ER+)
• Human epidermal growth factor receptor-negative (HER2-)

NOTE: If your patient has been diagnosed with non-invasive breast cancer, ductal carcinoma in situ (DCIS) she may be eligible for the Oncotype DX Breast DCIS Score test.

When to order the test

Because the goal of the Breast Recurrence Score test is to facilitate treatment planning, the best time to order the test is before treatment planning begins. Ordering is easy, and the test can be run on a post-surgery (lumpectomy or mastectomy) tumour sample or on a core biopsy.

Access to the test in Canada

The Oncotype DX test has been available in Canada since the end of 2007, and, to date, over 50,000 Canadian women have benefited from testing. In all Canadian provinces (British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, Nova Scotia, PEI, New Brunswick and Newfoundland), the test is publicly funded for patients with early stage node negative breast cancer. The test is also publicly funded for patients with node positive breast cancer (1-3 nodes) in British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick, Nova Scotia, PEI and Newfoundland. Individual patients also have the option of paying for the test themselves if there is no coverage in their province, or if they do not meet pre-specified provincial eligibility criteria.

The Oncotype DX test is the only multigene assay that is both predictive of chemotherapy treatment effect and prognostic of disease outcome^5-13

The Oncotype DX test is the only test clinically validated to identify patients likely to benefit from chemotherapy, or not.^5–13

Learn more about the difference between prognostic and predictive tests

Prediction of chemotherapy benefit based on prospective clinical trials makes the Oncotype DX test unique

*TAILORx showed that endocrine therapy was non-inferior to chemoendocrine therapy in node-negative patients with Recurrence Score^® results 11-25. RxPONDER showed that node-positive postmenopausal patients with Recurrence Score^® results 0-25 do not benefit from chemotherapy while premenopausal patients with 1 to 3 positive nodes and RS^® results 0-25 significantly benefit from chemotherapy

Development of the Oncotype DX Test

The Oncotype DX test was developed to assess disease prognosis and quantify the benefit from chemotherapy (CT) in patients with early-stage, HR+, HER2- breast cancer⁹. Genes were selected accordingly, and the test’s predictive abilities were validated in two-arm retrospective prospective clinical trials (comparing CT+ Endocrine Therapy (ET) versus ET alone): the NSABP B-20 for node-negative patients^5,13 and SWOG-8 814 for node-positive patients⁸ trials. The landmark TAILORx study⁶ showed that ET was non-inferior to CT + ET in patients with node-negative disease and Recurrence Score results 11 to 25. In addition, RxPONDER study¹¹ initial results demonstrated that postmenopausal patients with Recurrence Score results 0-25 can be spared chemotherapy independent of clinical pathologic parameters. This supports earlier research indicating that the majority of patients do not benefit from the addition of chemotherapy.⁴

The Oncotype DX test was developed to predict chemotherapy benefit based on a unique understanding of tumour biology⁹. The Oncotype DX test quantifies expression of 21 genes in fixed, paraffin-embedded tumour tissue using high-throughput, real-time, reverse transcription-polymerase chain reaction. Three independent breast cancer studies were used to select the panel of 16 cancer-related and five reference genes that are tested in the Oncotype DX assay. Based on the expression levels of the 21 genes, a Recurrence Score result is calculated for each tumour sample.

The Oncotype DX test reveals individual tumour biology based on measuring the expression of 21 genes⁹

16 Cancer Genes and 5 Reference Genes

What information does the Oncotype DX test provide?

The Oncotype DX test identifies patients who will benefit from adjuvant chemotherapy, or not, by providing three pieces of information: the Recurrence Score result, the risk of distant recurrence, and the estimated chemotherapy benefit.