Multiple cycles of dose-intensive chemotherapy with repeated stem cell support as induction treatment in metastatic breast cancer: a feasibility study

The purpose of this trial was to study feasibility and tolerance of a dose- intensive multicyclic alternating induction chemotherapy with repeated stem cell support in a series of 43 metastatic breast cancer patients. Anthracy cline-naive patients (n = 21) received cyclophosphamide 2.5 g/m(2) plus dox orubicin 80 mg/ml alternating every 14 days with paclitaxel 200-350 mg/m(2) plus cisplatin 120 mg/ml. Patients who had previously received anthracycli nes (n = 22) received cisplatin 120 mg/ml plus etoposide 600 mg/m(2) altern ating with paclitaxel 200-350 mg/m(2) plus ifosfamide 8 g/m(2). Peripheral blood stem cells were infused after every course except the first, with a m edian CD34(+) dose of 2.1 X 10(6)/kg per cycle. Positive selection of CD34( +) cells was performed in good mobilizers. The median number of cycles admi nistered was six (4-8), and the time interval between them was 17 days. Med ian summation dose intensities (SDI) actually administered for the CA-TP an d PE-TI protocol were 4.95 and 4.69, respectively (87% of scheduled SDI). T here were 15 complete (35%) and 21 partial responses (49%), for an overall response rate of 84% (95% CI, 73%-95%). Infection or neutropenic fever occu rred in 50% of the cycles. There was one treatment-related death. After a m edian follow-up of 26 months, the median event-free-survival was 12 months (95% CI: 10-14) and overall survival was 31 months. These high dose-intensi ty induction treatments seem to be feasible with sequential stem cell suppo rt.