Ifosfamide bolus followed by five days continuous infusion in extensively pretreated patients with advanced breast cancer: A phase II study

Purpose: A phase II study with ifosfamide in pretreated patients with advan ced breast cancer was performed to determine the objective response rate, t he toxicity and the feasibility of the regimen. Methods & study design: Pat ients enrolled had advanced breast cancer pretreated with at least one prev ious regimen of chemotherapy for advanced disease, Treatment consisted of i fosfamide infused at a dose of 2 g/m(2) iv in 4 hrs followed by ifosfamide, 8 g/m(2) iv in 120 hrs in ambulatory treatment, using a portable external pump system. The total dose of ifosfamide was 10 g/m(2); mesna (4 g/m(2) iv ) was administered mixed with ifosfamide in 120 hrs Cycles were repeated ev ery 3 weeks. Three patients were pretreated with neoadjuvant and 15 with ad juvant chemotherapy. All patients were treated for advanced disease (median number of regimens, 1; range, 1-3): 21 with the cyclophosphamide-containin g regimen and 15 with adryamicin. Sixteen patients received one or more lin es of endocrine therapy. Fifteen patients had dominant site in viscera, 6 i n bone, and only one in soft tissue; 17 patients had more than one site of disease. Results: Twenty-two patients were enrolled and all were assessable for response and toxicity. A partial response was reached in 5 patients (2 3%; 95% confidence limits 5% to 60%). Hematologic toxicity was the dose-lim iting side effect; grade 4 leukopenia occurred in 10 patients (46%). Conclu sions: Considering the response rate obtained in our series of intensively pretreated patients, the results seem to indicate that the regimen is activ e and could be included among the possible options in the treatment of pati ents with refractory, poor-prognosis, advanced breast carcinoma.