NEW YORK – Researchers at the MD Anderson Cancer Center, Loyola University Chicago Stritch School of Medicine, and elsewhere have determined that a breast cancer recurrence score provided by the Genomic Health 21-gene expression assay OncotypeDX may provide valuable prognostic information on locoregional disease recurrence that may aid in decision-making about radiotherapy for postmenopausal women with node-positive, estrogen receptor- or progesterone receptor-positive breast cancer.