A phase II trial of dose-dense (biweekly) paclitaxel plus carboplatin as neoadjuvant chemotherapy for operable breast cancer

The aim of the present study is to investigate the efficacy and safety of dose-dense (biweekly) carboplatin and paclitaxel as a neoadjuvant treatment for operable breast cancer. Patients with previously untreated breast cancer (stages Ic–III) were treated with four cycles of paclitaxel (175 mg/m², intravenous drip, D1) and carboplatin (area under the curve of 5, D1). Patients with HER2+ disease simultaneously received trastuzumab (6 mg/kg initial dose with subsequent doses of 4 mg/kg biweekly). The primary endpoint was a pathologically complete response (pCR). Between January 2012 and February 2014, 110 patients were enrolled. The overall pCR rate was 35.45 % (39 of 110). The pCR rates for the different cancer subtypes were as follows: 10.53 % (2 of 19) among the patients with the luminal A subtype, 12.50 % (5 of 40) among the patients with the luminal B (HER2−) subtype, 58.33 % (14 of 24) among the patients with the luminal B (HER2+) subtype, 57.14 % (8 of 14) among the patients with the triple-negative subtype, and 76.92 % (10 of 13) among the patients with the HER2+ subtype. The patients experienced the following toxicity side effects: grade 3/4 neutropenia (N = 27, 24.55 %), grade 3/4 anemia (N = 6, 5.45 %), grade 3/4 thrombocytopenia (N = 2, 1.82 %), grade 3 alanine aminotransferase (ALT) elevation (N = 1, 0.91 %), grade 3 neuropathy (N = 3, 2.73 %), grade 3 pain (N = 2, 1.82 %), and grade 3 fatigue (N = 1, 0.91 %). In total, 19.09 % of the patients experienced treatment delay or discontinuation due to hematological toxicity, and one patient discontinued treatment due to non-hematological toxicity. Neoadjuvant biweekly paclitaxel plus carboplatin is a feasible therapy that achieved high pCR rates in patients with the HER2+, triple-negative, and luminal B (HER2+) cancer subtypes (NCT0205986).