Dr. Brufsky on Genomic Assays for Breast Cancer

Adam M. Brufsky, MD, PhD, associate director, Clinical Investigation, University of Pittsburgh, discusses genomic assays for breast cancer.

There are 2 commonly used genomic assays for breast cancer—the 21-Gene recurrence score assay, which is Oncotype DX, and the 70-gene signature test, which is MammaPrint. Two clinical trials using these assays have been done, TAILORx for Oncotype DX and MINDACT for MammaPrint.

There is no superior assay, states Brufsky. They are suited for different populations, but they both measure the same thing in that they identify a group of patients who do not require chemotherapy. Oncotype DX is suited for patients with node-negative breast cancer, while MammaPrint in the prospective trial was used for node-negative and node-positive disease. There will be node-positive data coming out from a trial called RxPONDER in the next few years as well, which may help clarify the optimal use of these assays.