Clinicopathological features, prognosis and influence in the adjuvant treatment of the risk recurrence groups determined by the 21 gene expression profile, Oncotype Dx®, in early breast cancer
Gerson Cwilich, R.; Alban de la Torre, L.F.; Villalobos Prieto, A.; Serrano Olvera, J.A.
Gaceta Medica de Mexico 148(2): 117-124
2012
ISSN/ISBN: 0016-3813 PMID: 22622310 Document Number: 659133
Adjuvant chemotherapy (ACT) reduces recurrence and mortality in breast cancer (BC); however, not all patients require ACT. Oncotype Dx® (ODX) explores the expression of 21 genes and the risk of recurrence BC. To determine the clinicopathologic characteristics, prognosis, and the prescription for ACT in early BC according to ODX risk groups. 36 patients with resected stage I-IIA BC, axillary lymph node-negative or 1-3+, hormonal receptor (HR)-positive, HER2 negative. Three groups were designed by ODX: low (LG), medium (MG) and high-risk groups (HG). LG 23 patients (63.9%), MG eight (22.2%) and HG five (13.9%). We detected high expression of Ki-67 in MG and HG in relation to LG, 21.1 and 32.5 versus 10.1%, respectively (p = 0.007) and lower ER-positive, 85.3, 85.4 and 56.9%, respectively (p = 0.005). Recurrence score: LG 12 (0-18), MG 23 (19-27) and HG 47 (36-57); p < 0.000. Pre-ODX, we planned ACT in 21/36 patients (58.3%) and post-ODX only 9/36 patients (25%) received it. No recurrences or deaths were observed in all groups. In early BC, 64% have low recurrence risk. High-risk cases presented elevated Ki-67 and lower ER expression. ODX modifies the therapeutic recommendation in 57.2% of cases.