A Phase II Study on the Safety and Efficacy of 5-Fluorouracil, Epirubicin, Cyclophosphamide (FEC) Followed by Paclitaxel in the Adjuvant Treatment of Breast Cancer

The incorporation of a taxane into an anthracycline-containing regimen in the adjuvant treatment of breast cancer is a promising approach. In this study, we aimed to evaluate the safety and efficacy of four cycles of FEC (fluorouracil 500 mg/m2, epirubicin 70 mg/m2, cyclophosphamide 500 mg/m2, every 3 weeks) followed by four cycles of paclitaxel (175 mg/m2 every 3 weeks) in the adjuvant treatment of node-positive and other high-risk breast cancer patients. A total of 88 female patients were enrolled. Mean age (± SD) of the patients was 47 ± 10 (min: 24; max: 71). The patients were followed for a median of 48 months (min: 20; max: 64). The most common side effects were nausea-vomiting (grade I-II: 91%; grade III: 2%), as well as hematological toxicity (grade I-II: 70%; grade III: 3%). Although all patients experienced some degree of toxicity, it was severe enough to be classified as grade III or IV in only 10 (11%) of the cases. Of note, six (8%) patients had grade I and only one (1%) had grade II cardiotoxicity. No grade III or IV cardiotoxicity was observed. The full eight cycles of study treatment could be administered to 75 patients (85%). Side effects necessitated the reduction of the doses of FEC and paclitaxel in one (1%) and three patients (3%), respectively. Median overall (OS) and disease-free survival (DFS) have not yet been reached. Five-year OS and DFS have been estimated to be 78% and 61%, respectively. We conclude that FEC followed by paclitaxel is a well-tolerated and feasible regimen in the adjuvant treatment of early breast cancer. Its efficacity is comparable with other commonly used regimens and merits evaluation in a phase III study.