A genetic test for women diagnosed with early-stage breast cancer may be able to predict which patients can safely skip chemotherapy without hurting their odds of beating the disease. The promising new findings resulted from a recent National Cancer Institute study published in the New England Journal of Medicine. For the study, researchers used a gene-activity test called Oncotype DX, which measures the activity of genes that control cell growth, to classify 10,253 women diagnosed with breast cancer as being either low, intermediate or high risk of cancer recurrence.

Scientists randomly selected women in the intermediate group to receive hormone therapy alone or with chemo. The high-risk group received both chemo and hormone therapy. Results from these arms of the study are not back yet, because they are ongoing. However, findings showed that women in the low-risk group who received no chemo had a less than 1 percent chance of their cancer coming back elsewhere in their bodies after five years. According to Clifford A. Hudis, MD, Chief of the Breast Cancer Medicine Service at Memorial Sloan Kettering Cancer Center, an independent expert who commented on the report, using the gene test in this way “lets us focus our chemotherapy more on the higher-risk patients who do benefit.” The test costs $4,175, but it’s covered by Medicare and many other health care insurance companies. In addition, other gene-activity tests that identify early-stage breast cancer patients who can bypass chemo are currently available.