Genomic Health has reported that The Lancet Oncology has published positive results from a study of Oncotype DX in postmenopausal women with node-positive, estrogen receptor-positive breast cancer. The study was conducted by the Southwest Oncology Group (SWOG), a National Cancer Institute-supported clinical trials cooperative group.

The Lancet Oncology published these results online as an ‘early release’ to coincide with additional data analyses, reinforcing that the Oncotype DX breast cancer test can help predict chemotherapy benefit in breast cancer patients with node-positive disease, said the company.

The study challenges the current treatment standard of adjuvant chemotherapy for all women with lymph node-positive breast cancer.

The researchers analysed 367 tumor samples from node-positive, estrogen receptor-positive breast cancer patients who participated in the SWOG/Breast Cancer Intergroup of North America trial. It evaluated CAF chemotherapy followed by tamoxifen versus tamoxifen-alone, to determine the prognostic and predictive effects of the Oncotype DX Recurrence Score.

The Oncotype DX breast cancer test is the multigene expression test commercially available and has clinical evidence validating its ability to predict the likelihood of chemotherapy benefit as well as recurrence in early-stage breast cancer.

Additionally, the test report provides quantitative scores for certain individual genes. The Oncotype DX breast cancer test has been evaluated in 13 clinical studies involving more than 4,000 breast cancer patients worldwide, including a large validation study published in The New England Journal of Medicine and a chemotherapy benefit study published in the Journal of Clinical Oncology.

Kathy Albain, professor of Medicine, hivision of Hematology/Oncology, department of Medicine and senior author of the study, said: “These studies indicate that the Oncotype DX Recurrence Score result can provide beneficial clinical information beyond standard pathology testing for node-positive breast cancer patients.”