21-Gene Assay Recurrence Score and Risk of Locoregional Recurrence in Hormone Receptor–Positive, Node-Positive Breast Cancer
A retrospective analysis from the Southwest Oncology Group S8814 trial, reported by Wendy A. Woodward, MD, PhD, of the Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, and colleagues in JAMA Oncology,1 showed that a low 21-gene assay recurrence score was associated with a reduced risk of locoregional recurrence in postmenopausal women with hormone receptor–positive, node-positive breast cancer receiving adjuvant therapy, including a large subgroup that underwent mastectomy without radiation therapy.
Wendy A. Woodward, MD, PhD
In the trial, women were randomly assigned to receive adjuvant tamoxifen alone, chemotherapy followed by tamoxifen, or concurrent tamoxifen and chemotherapy. The current analysis included 316 patients and excluded 37 who received both mastectomy and radiotherapy, 9 who received breast-conserving surgery without documented radiotherapy, and 5 with an unknown surgical type.
The investigators concluded: “This study found that higher recurrence scores were associated with increased [locoregional recurrence] after adjustment for treatment, type of surgical procedure, and number of positive nodes. This finding suggests that the recurrence score may be used, along with accepted clinical variables, to assess the risk of [locoregional recurrence] during radiotherapy decision-making.”
DISCLOSURE: The study was funded by grants from the National Cancer Institute of Canada and Canadian Cancer Society and by Genomic Health Inc. For full disclosures of the study authors, visit jamanetwork.com.
1. Woodward WA, Barlow WE, Jagsi R, et al: Association between 21-gene assay recurrence score and locoregional recurrence rates in patients with node-positive breast cancer. JAMA Oncol. January 9, 2020 (early release online).