Induction, mobilization of peripheral blood stem cells (PBSC), high-dose chemotherapy and PBSC infusion in patients with untreated stage IV breast cancer: outcomes by intent to treat analyses

Abstract

We investigated the outcomes of patients with breast cancer undergoing induction chemotherapy, mobilization of peripheral blood stem cells (PBSC) and high-dose chemotherapy (HDC) with PBSC infusion. One hundred and fourteen patients with untreated stage IV breast cancer, with a median age of 46 years (range 24–62), were entered on a phase II trial consisting of: (1) doxorubicin, 5-flurouracil, methotrexate (AFM) × 4 courses at 2 week intervals; (2) cyclophosphamide (4 g/m²), etoposide (600 mg/m²), cisplatin (105 mg/m²) (CEP), filgrastim (6 μ All patients received AFM, 107 (94 g/kg/day) and PBSC collection; (3) cyclophosphamide (6 g/m²), thiotepa (500 mg/m²), carboplatin (800 mg/m²) (CTCb) followed by PBSC infusion. %) received CEP, 93 (82%) received CTCb and PBSC as per protocol and 99 (87%) ultimately received HDC and PBSC. There was one infectious death after AFM and all other deaths were associated with progressive disease. Fifty-two patients (46%) are alive, 21 (18%) without progression, at a median 31 months (range 22–47). The probabilities of survival and progression-free survival at 3.5 years were 0.40 and 0.17, respectively. All 62 patients with visceral disease and/or a prior history of doxorubicin adjuvant therapy have relapsed or progressed. We conclude that the sequential administration of AFM, CEP and CTCb followed by PBSC resulted in long-term PFS only in patients who were NED, had bone-only disease or had lymph node or soft tissue disease with or without bone disease. Other strategies, aimed at improving responses to initial therapy, improving HDC regimens and/or developing immunomodulatory therapies, will be necessary to improve PFS for patients who fail doxorubicin adjuvant or who have visceral disease.