Dose-dense paclitaxel versus docetaxel following FEC as adjuvant chemotherapy in axillary node-positive early breast cancer: a multicenter randomized study of the Hellenic Oncology Research Group (HORG).

Adding a taxane to anthracycline-based adjuvant chemotherapy prolongs survival in node-positive early breast cancer. However, which is the preferable taxane in a dose-dense regimen remains unknown. We conducted a randomized study to compare the efficacy of dose-dense paclitaxel versus docetaxel following 5-fluorouracil, epirubicin, and cyclophosphamide (FEC) as adjuvant chemotherapy in women with node-positive early breast cancer. Following surgery women with HER2-negative breast cancer and at least one infiltrated axillary lymph node were randomized to receive four cycles of FEC (700/75/700 mg/m(2)) followed by four cycles of either paclitaxel (175 mg/m(2)) or docetaxel (75 mg/m(2)). All cycles were administered every 14 days with G-CSF support. The primary endpoint was disease-free survival (DFS) at 3 years. Between 2004 and 2007, 481 women were randomized to paclitaxel (n = 241) and docetaxel (n = 240). After a median follow-up of 6 years, 51 (21%) and 48 (20%) women experienced disease relapse (p = 0.753) and there was no significant difference in DFS between the paclitaxel- and docetaxel-treated groups (3-year DFS 87.4 vs. 88.3%, respectively; median DFS not reached; p = 0.633). Toxicities were manageable, with grade 2-4 neutropenia in 21 versus 31% (p = 0.01), thrombocytopenia 0.8 versus 3.4% (p = 0.06), any grade neurotoxicity 17 versus 7.5% (p = 0.35) and onycholysis 4.9 versus 12.1% (p = 0.03) for patients receiving paclitaxel and docetaxel, respectively. There were no toxic deaths. Dose-dense paclitaxel versus docetaxel after FEC as adjuvant chemotherapy results in a similar 3-year DFS rate in women with axillary node-positive early breast cancer. Due to its more favorable toxicity profile, paclitaxel is the taxane of choice in this setting.