OBJECTIVE Ifosfamide is an active drug in advanced breast cancer. Short-term continuous infusion schedules have been evaluated with encouraging results. The aim of the study was to evaluate in patients with advanced breast cancer a 14-day infusion schedule previously tested at our center in soft tissue sarcomas. METHODS From July 1998 to February 2000, 26 consecutive patients with heavily pretreated breast cancer, progressing during protracted continuous infusion of fluorouracil, were treated with ifosfamide at the dose of 800 mg/m2/day for 14 consecutive days by means of an elastomeric pump via an in-dwelling Groshong catheter. The median age of the patients was 52 years (range, 32-67) and median PS was 1 (range, 1-3). All patients were pretreated with anthracyclines or taxanes; the median number of chemotherapy lines in the metastatic phase was 2 (range, 1-4). Predominant metastatic sites wen soft tissues in 5 patients, lung in 6, liver in 7 and serosal cavities in 3. RESULTS Twenty-four patients were assessable for response Two complete responses and 2 partial remissions were noted for an overall 16.6% response rate. The duration of response was 3+, 5, 8 and 10 months, respectively. Stabilization or mi nor response was observed in 2 more patients. The main tox ic effect was myelosuppression (grade 1-2 in 15 patients grade 3-4 in 4). Other toxicities included nausea in 14 patients (grade 3 in 2) and grade 1-2 vomiting in 2 patients. Hair lost or alopecia was universal. CONCLUSIONS The regimen yielded some clinically useful re sponses with acceptable toxicity. Its evaluation in less ad vanced cases appears to be warranted.