For node-positive, early breast cancer patients
Challenging Node-Positive Cases - Drs. Jeremy Force and Christy Russell
The Oncotype DX Breast Recurrence Score result is predictive of chemotherapy benefit in your postmenopausal patients with HR+, HER2-, node-positive (1-3 positive nodes), early-stage, invasive breast cancer as demonstrated by the SWOG-8814 study.1 Data from SWOG-8814 and the RxPONDER randomized prospective trial show that a substantial proportion of these patients may be spared chemotherapy.1-5
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.
How does the Oncotype DX test help guide treatment decisions?
SWOG 8814 established the Oncotype DX® test as predictive of CT benefit in node-positive postmenopausal patients1. Initial results from the RxPONDER study add to the findings of SWOG 8814 by providing a refined estimate of CT benefit in N1 patients with the following results6:
- N1 postmenopausal patients with Recurrence Score® results 0-25 may be spared chemotherapy regardless of the number of affected nodes, tumour grade or size.6
- N1 premenopausal patients with Recurrence Score results 0-25 derive a 2.9% benefit from chemotherapy based on distant recurrence at 5 years.6
Use of the Oncotype DX test may reduce the risk of overtreatment with chemotherapy1,6
Node positive patients are believed to have higher clinical risk and worse prognosis if not treated with chemotherapy9. Average chemotherapy treatment rates without genomic testing are in the range of 70% for this patient population7-8. RxPONDER demonstrated that many of these patients may be overtreated6, and the Oncotype DX test can help make informed treatment decisions.
Nodal status, despite being of prognostic value, does not predict the Recurrence Score result and the underlying tumour biology4
Overall, 566,438 tumour specimens with known nodal status were examined by the Genomic Health laboratory (now Exact Sciences) from February 2004 to August 20174
CLINICAL UTILITY OF THE ONCOTYPE DX ASSAY
In summary, adjuvant chemotherapy may be guided with the Oncotype DX test to identify the majority of node-positive patients (with up to 3 positive nodes) who will not benefit from the addition of chemotherapy.
The Oncotype DX Breast Recurrence Score* test should be used for:
- All patients for whom chemotherapy can potentially be spared
- All patients for whom chemotherapy can potentially be life-saving
*For early stage, HR+, HER2- patients with up to 3 involved nodes