19 February, 2019

Landmark TAILORx study results make the Oncotype DX Breast Recurrence Score® Assay the new Standard of Care.

Breast cancer is the most common type of cancer in women worldwide. Hormone-receptor-positive, axillary node-negative disease accounts for approximately half of all cases of breast cancer in general.  Most of the breast cancer cases knew since the diagnosis that they were almost certainly going to face radiation or chemotherapy, or a combination of both.  Although, several clinical trials have shown that the majority of these patients received chemotherapy unnecessarily and a very low percentage of them did have an important benefit from chemotherapy.

The federally funded Trial Assigning Individuaized Options for Treatment (RX) or TAILORx clinical trial enrolled 10,000 women with early-stage breast cancer and showed that most women with hormone receptor (HR)–positive, HER2-negative, axillary node–negative early-stage breast cancer and a mid-range score on a 21-tumor gene expression assay (Oncotype DX® Breast Recurrence Score) do not need chemotherapy after surgery. The study found no improvement in disease-free survival when chemotherapy was added to hormone therapy in this group, which accounts for about two-thirds of women who participated in the trial. The findings will have an immediate impact on clinical practice, sparing thousands of women the side effects of chemotherapy.

Oncotype DX Breast Recurrence Score®: The only internationally validated prognostic and predictive Assay

Based on evidence from several prior studies, the 21-gene expression assay is widely used to provide prognostic information about the risk of breast cancer recurrence within 10 years and to predict which patients are most likely to derive a large benefit from chemotherapy. The test is performed on a tumor biopsy sample.

Chemotherapy: The dark side

The side effects of chemotherapy for breast cancer can be significant. Short-term side effects that occur during chemotherapy include nausea, vomiting, hair loss, fatigue, and infection, and, in younger women, early menopause or infertility. Neuropathy is another common side effect, with symptoms including numbness, tingling, or pain in the hands and feet, which may sometimes be permanent. Certain delayed side effects that may occur months or years after chemotherapy are rare, but potentially serious, including heart failure and leukemia.

The numerous side effects of chemotherapy make it necessary to find out the majority of these patients who do not benefit from it so they can turn to the most suitable alternative treatment options according to their unique tumor profile.

“Before TAILORx, there was uncertainty about the best treatment for women with a mid-range score of 11–25 on the Oncotype DX Breast Recurrence Score test. The trial was designed to address this question and provides a very definitive answer. Any woman with early-stage breast cancer 75 years or younger should have the test and discuss the results of TAILORx with her doctor to guide her decision regarding chemotherapy after surgery to prevent recurrence.” said Dr. Sparano.

This study, which never would have happened without federal funding for cancer research, will transform care immediately, and for the better. These data provide critical reassurance to doctors and patients that they can use genomic information to make better treatment decisions in women with early-stage breast cancer. Practically speaking, this means that thousands of women will be able to avoid chemotherapy, with all of its side effects, while still achieving excellent long-term outcomes.