Large randomized controlled trial finds that 70% of women with early-stage invasive breast cancer do not need chemotherapy in addition to hormone therapy based on a genomic test for this type of breast cancer.
This trial involved more than 10,000 patients across six countries with the most common form of early breast cancer, hormone-receptor positive, HER-2 negative breast cancer that hadn’t spread to the lymph nodes.
The genomic test (called Oncotype DX) measures the expression of 21 genes in tumor tissue and predicts the risk of recurrence on a scale of 0 to 100.
For those individuals with test scores between 11 and 25, there was a similar rate of cancer-free survival after 9 years for those who had chemo combined with hormone therapy and those who had hormone therapy alone. This new finding may spare a lot of unnecessary chemotherapy in certain patients with breast cancer.