Prognostic Impact of the 21-Gene Recurrence Score Assay Among Young Women With Node-Negative and Node-Positive ER-Positive/HER2-Negative Breast Cancer
Menée auprès de 509 patientes atteintes d'un cancer du sein ER+ HER2- de stade I à III et âgées de 40 ans ou moins (âge médian au diagnostic : 37,2 ans ; durée médiane de suivi : 6 ans), cette étude évalue, en fonction de la présence d'un envahissement des ganglions axillaires, la pertinence du système de score fourni par le test Oncotype DX pour prédire la survie sans récidive distante après une chimiothérapie adjuvante
PURPOSE : The 21-gene recurrence score (RS) assay is prognostic among women with early-stage estrogen receptor–positive (ER+) and human epidermal growth factor receptor 2–negative (HER2−) breast cancer and is used to inform recommendations for chemotherapy. Women ≤ 40 years of age represent a minority of patients studied using gene expression profiles.
METHODS : The Young Women's Breast Cancer Study is a prospective cohort of women diagnosed with breast cancer at age ≤ 40 years and enrolled patients between 2006 and 2016 (N = 1,302). We identified patients with stage I-III ER+/HER2− breast cancer. The RS assay was performed on banked specimens for patients who had not been tested clinically. Distant recurrence-free survival (DRFS) was assessed by TAILORx and traditional RS risk groups among patients with axillary node–negative (N0) and limited node–positive (N1) breast cancer.
RESULTS : Among eligible women (N = 577), 189 (33%) had undergone RS testing, and 320 (56%) had banked specimens sufficient for testing. Median follow-up was 6.0 years. Median age at diagnosis was 37.2 years; 300 of 509 patients (59%) had N0 breast cancer, of whom 195 (65%) had an RS of 11-25 and fewer than half (86 of 195; 44%) received chemotherapy. Six-year DRFS rates were 94.4% and 92.3% (RS < 11), 96.9% and 85.2% (RS 11-25), and 85.1% and 71.3% (RS ≥ 26) among women with N0 and N1 disease, respectively.
CONCLUSION : The RS assay is prognostic among young women with node-negative and limited node-positive breast cancer, representing a valuable tool for risk stratification. Disease outcomes with a median follow-up of 6 years among young women with N0 disease and an RS of 0-25, a minority of whom received chemotherapy, and node-positive disease with an RS < 11 were very good, whereas those with N0 disease and an RS ≥ 26 or N1 disease with an RS ≥ 11 experienced substantial risk of early distant recurrence.
Journal of Clinical Oncology , article en libre accès, 2018