Impact of Tumor Biology, Particularly Triple-negative Status, on Response to Pre-operative Sequential, Dose-dense Epirubicin, Cyclophosphamide Followed by Docetaxel in Breast Cancer

The central objective of this study was to determine the predictive impact of several established tumor biological factors (PgR, ER, HER2 and Ki-67) on response to pre-operative chemotherapy in primary breast cancer. 59 primary M0 breast cancer patients received pre-operative sequential dose-dense epirubicin and cyclophosphamide followed by docetaxel (19 patients at dosage 100 mg/m(2), 40 patients at 75 mg/m(2)). Pathological complete remission (pCR) occurred in 17 patients (29%) and at least partial remission in 42 (71%). Higher proliferation (Ki-67) and lack of hormone receptors (either or both) were significant predictive factors for pCR; moreover, 8/11 (73%) patients with triple-negative tumors (HER2(-)/ER(-)/PgR(-)) had pCR (p=0.001). Breast conserving surgery was achieved in 46/59 patients (78%). Hand-foot syndrome occurred in 12/19 patients treated at the higher docetaxel dosage but only 1/40 of the remaining patients. Higher docetaxel dosage was associated with improved pCR in the non-triple-negative subgroup. The tumor biology of hormone receptor-negative, especially triple-negative, and highly proliferating breast cancer is associated with strongly positive response to dose-dense, pre-operative epirubicin/cyclophosphamide/docetaxel chemotherapy.