Clinical Outcomes in Early Breast Cancer With a High 21-Gene Recurrence Score of 26 to 100 Assigned to Adjuvant Chemotherapy Plus Endocrine Therapy: A Secondary Analysis of the TAILORx Randomized Clinical Trial
Menée à partir des données d'un essai multicentrique portant sur 9 719 patientes atteintes d'un cancer du sein HR+ ERBB2- de stade précoce et sans envahissement des ganglions axillaires (âge : de 23 à 75 ans), cette étude évalue la proportion de femmes présentant un score Oncotype DX supérieur ou égal à 26 et bénéficiant ainsi d'une chimiothérapie adjuvante en combinaison ou non avec un traitement endocrinien, puis estime chez ces patientes les taux d'absence de récidive à 5 ans et les taux de survie sans maladie invasive
Importance : A high 21-gene recurrence score (RS) by breast cancer assay is prognostic for distant recurrence of early breast cancer after local therapy and endocrine therapy alone, and for chemotherapy benefit.
Objective : To describe clinical outcomes for women with a high RS who received adjuvant chemotherapy plus endocrine therapy in the TAILORx trial, a population expected to have a high distant recurrence rate with endocrine therapy alone.
Design, Setting, and Participants : In this secondary analysis of data from a multicenter randomized clinical trial, 1389 women with hormone receptor–positive, ERBB2-negative, axillary node-negative breast cancer, and a high RS of 26 to 100 were prospectively assigned to receive adjuvant chemotherapy in addition to endocrine therapy. The analysis was conducted on on May 12, 2019.
Interventions : The adjuvant chemotherapy regimen was selected by the treating physician.
Main Outcomes and Measures : Freedom from recurrence of breast cancer at a distant site, and freedom from recurrence, second primary cancer, and death (also known as invasive disease-free survival [IDFS]).
Results : Among the 9719 eligible women, with a mean age of 56 years (range 23-75 years), 1389 (14%) had a recurrence score of 26 to 100, of whom 598 (42%) had an RS of 26 to 30 and 791 (58%) had an RS of 31 to 100. The most common chemotherapy regimens included docetaxel/cyclophosphamide in 589 (42%), an anthracycline without a taxane in 334 (24%), an anthracycline and taxane in 244 (18%), cyclophosphamide/methotrexate/5-fluorouracil in 52 (4%), other regimens in 81 (6%), and no chemotherapy in 89 (6%). At 5 years, the estimated rate of freedom from recurrence of breast cancer at a distant site was 93.0% (standard error [SE], 0.8%), freedom of recurrence of breast cancer at a distant and/or local regional site 91.0% (SE, 0.8%), IDFS 87.6% (SE, 1.0%), and overall survival 95.9% (SE, 0.6%).
Conclusions and Relevance : The estimated rate of freedom from recurrence of breast cancer at a distant site in women with an RS of 26 to 100 treated largely with taxane and/or anthracycline-containing adjuvant chemotherapy regimens plus endocrine therapy in the prospective TAILORx trial was 93% at 5 years, an outcome better than expected with endocrine therapy alone in this population.
Trial Registration : ClinicalTrials.gov identifier NCT00310180
JAMA Oncology , article en libre accès, 2018