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.1–3 The vast majority of patients with HR+, HER2- early-stage breast cancer do not benefit from adjuvant chemotherapy.4
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
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, Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick, 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 outcome5–13
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 patients5,13 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.
The Oncotype DX test for node-negative patients
In node-negative, early-stage, HR+, HER2- breast cancer patients, studies including > 95,000 patients have established that the Oncotype DX test consistently identifies the vast majority of patients (80%) who can be spared chemotherapy and the important minority (20%) who may substantially benefit from it.5,6,9,13–15 This includes the largest prospective, randomized adjuvant clinical trial in breast cancer: the landmark TAILORx study, which enrolled more than 10,000 patients.6
Patient selection using the Oncotype DX test in node-negative patients
a The Oncotype DX test consistently identifies the ∼80% of ER+/HER2-/EBC patients who can avoid chemotherapy, and 20% of patients for whom it may be life-saving6,13-16,18-19
The Oncotype DX test for node-positive patients
The test’s predictive ability in the node-positive setting was validated in the two-arm prospective retrospective clinical trial SWOG-8814 for postmenopausal patients (comparing CT+ Endocrine Therapy (ET) versus ET alone)8. Initial results from the RxPONDER study further refined the chemotherapy benefit estimates for patients with Recurrence Score results 0-25 and 1 to 3 positive nodes. Results from these trials are summarized in the graphic below. Postmenopausal patients with one to three positive lymph nodes and Recurrence Score results 0-25 did not benefit from chemotherapy in addition to endocrine therapy8,11. Premenopausal patients with Recurrence Score results 0-25 and 1 to 3 positive nodes derived a 2.9% chemotherapy benefit based on distant recurrence at 5 years.11
Patient selection using the Oncotype DX test in node-positive patients8
*CT benefit expressed in percentage points based on probability of distant recurrence with/without CT at 5 years. No CT benefit is considered for an absolute benefit <1%. Benefit of chemotherapy for premenopausal N1 patients with RS® results 26-100 has not been formally assessed in a randomized study. The benefit derived from chemotherapy was significant for RS® results 0-13 and 14-25 in the RxPONDER study and it is inferred to be substantial for patients with RS® 26-100.
Guiding treatment with the Oncotype DX test
The majority of HR+, HER2- early breast cancer patients can be speared chemotherapy when decisions are guided by the Oncotype DX test.
CT benefit expressed in percentage points based on probability of distant recurrence with/without CT;
No CT benefit is considered for an absolute benefit <1%;
Node-negative (N0) patients: TAILORx analyses were performed by age and demonstrated patients ≤ 50 years derived some clinically meaningful benefit from CT at 9 years starting with an RS® result of 16;
Node-positive (N1) patients: RxPONDER data were analyzed according to menopausal status and demonstrated that premenopausal patients with RS® results 0-25 overall derived benefit from chemotherapy at 5 years.
* Benefit of chemotherapy for premenopausal N1 patients with RS® results 26-100 has not been formally assessed in a randomized study. The benefit derived from chemotherapy was significant for RS results 0-13 and 14-25 in the RxPONDER study and it is inferred to be substantial for patients with RS result 26-100.