Clinical outcomes of neoadjuvant chemotherapy for patients with breast cancer: Tri-weekly nanoparticle albumin-bound paclitaxel followed by 5-fluorouracil, epirubicin, and cyclophosphamide: a retrospective observational study.

Neoadjuvant chemotherapy (NAC) using the combination of anthracycline and taxanes is the standard regimen for patients with primary breast cancer. Among the taxanes, conventional paclitaxel (PTX) and docetaxel have usually been adopted in the neoadjuvant or adjuvant setting. Nanoparticle albumin-bound paclitaxel (nab-PTX) is a solvent-free formulation that can be delivered to cancer cells at higher doses than conventional PTX. This study is a retrospective observational study in a single institution. We evaluated the efficacy and safety of nab-PTX followed by 5-fluorouracil, epirubicin, and cyclophosphamide (FEC) in the neoadjuvant setting. In this study, 50 patients with primary breast cancer received nab-PTX (q3w, 260 mg/m ± trastuzumab 6 mg/kg) followed by FEC (q3w, 5-fluorouracil 500 mg/m, epirubicin 100 mg/m, and cyclophosphamide 500 mg/m) prior to surgery. The efficacy was evaluated using the clinical response rate (CRR), pathological complete response (pCR) rate, and Ki67 labeling index. Safety was evaluated using the frequency of treatment-related adverse events and relative dose intensity (RDI). All patients received at least one course of chemotherapy. The CRR and pCR rate were 88.0% and 40.0%, respectively. The mean Ki67 labeling index was significantly decreased from 47.7% to 24.6% after NAC. The safety profiles were comparable with previously reported regimens, and high RDIs were obtained (97.2% for nab-PTX and 95.5% for FEC). This study illustrated the efficacy and tolerability of a neoadjuvant regimen of nab-PTX followed by FEC.