New NCCN Breast Cancer Guidelines Recognise Oncotype DX Breast Recurrence Score as the “Preferred” and Only Multigene Test to Predict Chemotherapy Benefit in Node-positive Early-stage Breast Cancer

Exact Sciences today announced that its Oncotype DX Breast Recurrence Score test has been recognised as the only test that can be used for prediction of chemotherapy benefit in early-stage breast cancer patients with 1-3 positive axillary lymph nodes, including micro metastases, by the National Comprehensive Cancer Network (NCCN)ii in its updated guidelines for breast cancer. iii The Oncotype DX test is now the only test classified as “preferred” with the highest level of evidence for node-negative and postmenopausal node-positive patients.

In addition, the Oncotype DX test is incorporated in the node-negative and postmenopausal node-positive NCCN treatment algorithms with a recommendation of “strongly consider”, using cutoffs defined by the TAILORxiv and RxPONDER trials to select patients for chemotherapy treatment.

NCCN is an alliance of 21 world-leading cancer centers dedicated to improving the quality and effectiveness of care provided to patients with cancer. The guidelines are updated on a regular basis according to current evidence. The latest version can be accessed online.

This guideline update follows the recent presentation of initial results from the Rx for Positive Node, Endocrine Responsive Breast Cancer, or RxPONDER, trial, led by the independent SWOG Cancer Research Network and sponsored by the National Cancer Institute. One of the largest clinical trials in node-positive hormone receptor (HR)-positive, HER2-negative early breast cancer, RxPONDER enrolled more than 5,000 women with up to three positive nodes and successfully defined the benefit of chemotherapy in patients with Oncotype DX Breast Recurrence Score results of 0 to 25.

RxPONDER showed a different effect of chemotherapy based on Recurrence Score results for postmenopausal and premenopausal women. Postmenopausal women with Recurrence Score results 0-25 were not observed to show benefit from chemotherapy and may avoid the associated side effects of the treatment. Importantly, no chemotherapy benefit was observed regardless of the number of affected nodes, tumor grade, or size. The first trial results also demonstrated that premenopausal patients with a Recurrence Score result 0-25 derived a 2.9% benefit from chemotherapy on distant recurrence at five years.

Approximately 25% of patients diagnosed with HR-positive, HER2-negative early breast cancer have a tumour that has spread to their lymph nodes and two out of three are postmenopausal. v The vast majority of these patients currently receive chemotherapyvi although approximately 85% of them have Recurrence Score results of 0 to 25. Vii

The SWOG investigators intend to publish the detailed RxPONDER results in a peer-reviewed publication.