High-dose chemotherapy and autologous stem cell support followed by post-transplant doxorubicin and taxol as initial therapy for metastatic breast cancer: Hematopoietic tolerance and efficacy

A multistep HDC regimen was designed as first-line chemotherapy for MBC. Twenty-four patients with MBC and no previous chemotherapy for metastatic disease were treated with high-dose cyclophosphamide (5000 mg/m²), and etoposide (1000 mg/m²) (CyVP16), followed by granulocyte colony-stimulating factor (G-CSF). Peripheral blood stem cells (PBSCs) were collected. Subsequently patients received cyclophosphamide (6000 mg/m²), thiotepa (500 mg/m²) and carboplatin (800 mg/m²) (CTCb) with hematopoietic rescue. Upon recovery from hematopoietic and gastrointestinal toxicity three cycles of doxorubicin (50 mg/m²) and taxol (150 mg/m²) were delivered. After CyVP16 42% of patients developed neutropenic fevers. There was one documented episode of bacteremia. Patients received CTCb 32 days after starting CyVP16. After CTCb the median number of days to ANC > 5 x 10⁹/l was 10 and to a platelet count > 20 x 10⁹/l was 14. Neutropenic fevers developed in 16 patients. There were no hemorrhagic episodes. A total of 69 cycles of doxorubicin and taxol were delivered (87% of planned). The median time from PBSC infusion to the first cycle was 38 days. The median time to the second cycle was 27 days and to the last cycle was 24 days. One patient developed congestive heart failure. Two episodes of neutropenic fevers were observed. No toxicity-related deaths were observed. Grafts are stable at 6 months post transplantation. This multistep regimen is feasible with acceptable toxicity.