A phase II neoadjuvant trial of sequential nanoparticle albumin-bound paclitaxel followed by 5-fluorouracil/epirubicin/cyclophosphamide in locally advanced breast cancer

Background: Neoadjuvant chemotherapy has become standard treatment for women with locally advanced breast cancer (LABC). Various regimens have explored the addition of newer agents to determine safety and efficacy. The aim of this phase II study was to incorporate albumin-bound paclitaxel with sequential anthracycline-based therapy. Patients and Methods: Sixty-six women with LABC but without prior treatment and regardless of hormone receptor or HER2 status were enrolled. All patients were to receive albumin-bound paclitaxel weekly for 12 weeks followed by 5-fluorouracil/ epirubicin/cyclophosphamide (FEC) every 3 weeks for 4 cycles. Trastuzumab was allowed in HER2-positive (HER2⁺) patients. Primary endpoint was pathologic complete response (pCR; CR) in breast. Secondary endpoints included pCR in breast and nodes, clinical CR, 2-year progression-free survival, and overall survival. Results: Sixty-five patients received at least 1 dose of chemotherapy and were included in this analysis. Sixty-three patients completed 4 cycles of albumin-bound paclitaxel. Sixty-two patients received at least 1 dose of FEC, and 58 completed 4 cycles. Seventeen of 19 HER2⁺ women received trastuzumab. The pCR in breast was 29% (19 of 65). For the HER2⁺ subset, the pCR was 58% (11 of 19). Both albumin-bound paclitaxel and FEC were well tolerated. The most significant toxicities were grade 2/3 neuropathy (16%) with albumin-bound paclitaxel and grade 3/4 febrile neutropenia (7%) with FEC. Conclusion: Albumin-bound paclitaxel given over 12 weeks is well tolerated. Albumin-bound paclitaxel should be further evaluated in a randomized setting in both adjuvant and neoadjuvant trials.