Treatment of estrogen receptor-negative or hormonally refractory breast cancer with double high-dose chemotherapy intensification and bone marrow support

We have used high-dose therapy followed by randomization to receive or not receive autologous bone marrow infusion in 58 stage IV breast cancer patients (all were estrogen receptor-negative [ER-] or primary hormonal refractory). Patients received a median of four courses of induction chemotherapy and if stable or responding received two courses of intensive therapy with cyclophosphamide 4.5 to 5.25 g/m², etoposide 750 to 1,200 mg/m², and cisplatin 120 to 180 mg/m² (CVP). The complete remission (CR) rate after completion of the induction and intensive phases was 55%. Median progression-free interval from induction is 57 weeks with a projected 2-year progression-free survival of approximately 25%. Six of seven patients followed for greater than 2 years are still progression-free. Three favorable features predicted for improved progression-free survival are the following: (1) absent liver involvement, (2) absent soft tissue involvement, and (3) ≤ two disease sites (P values of .001, .013, and .048, respectively). Hormonal and menopausal status did not predict for progression-free survival. Major toxicities were infections secondary to neutropenia, with a 93% incidence of fever and a 38% incidence of sepsis. The treatment-related mortality rate was 9%, with three infectious, one coronary, and one late hemorrhage-related death of unknown cause. Longer follow-up is still needed to truly evaluate the possibility of long-term disease-free survival, but further studies of this approach to high-dose intensification in poor prognostic groups of stage IV breast cancer appear warranted.