Conventional-dose chemotherapy compared with high-dose chemotherapy plus autologous hematopoietic stem-cell transplantation for metastatic breast cancer.

Background: We conducted a randomized trial in which we compared high-dose chemotherapy plus hematopoietic stem-cell rescue with a prolonged course of monthly conventional-dose chemotherapy in women with metastatic breast can cer. Methods: Women 18 to 60 years of age who had metastatic breast cancer recei ved four to six cycles of standard combination chemotherapy. Patients who h ad a complete or partial response to induction chemotherapy were then rando mly assigned to receive either a single course of high doses of carboplatin , thiotepa, and cyclophosphamide plus transplantation of autologous hematop oietic stem cells or up to 24 cycles of cyclophosphamide, methotrexate, and fluorouracil in conventional doses. The primary end point was survival. Results: The median follow-up was 37 months. Of 553 patients who enrolled i n the study, 58 had a complete response to induction chemotherapy and 252 h ad a partial response. Of these, 110 patients were assigned to receive high -dose chemotherapy plus hematopoietic stem cells and 89 were assigned to re ceive conventional-dose chemotherapy. In an intention-to-treat analysis, we found no significant difference in survival overall at three years between the two treatment groups (32 percent in the transplantation group and 38 p ercent in the conventional-chemotherapy group). There was no significant di fference between the two treatments in the median time to progression of th e disease (9.6 months for high-dose chemotherapy plus hematopoietic stem ce lls and 9.0 months for conventional-dose chemotherapy). Conclusions: As compared with maintenance chemotherapy in conventional dose s, high-dose chemotherapy plus autologous stem-cell transplantation soon af ter the induction of a complete or partial remission with conventional-dose chemotherapy does not improve survival in women with metastatic breast can cer. (N Engl J Med 2000;342:1069-76.) (C) 2000, Massachusetts Medical Socie ty.