High-dose chemotherapy and autologous stem cell rescue for metastatic breast cancer: superior survival for tandem compared with single transplants.

During 1990-1999, we treated 60 patients with breast cancer who had distant metastases with high-dose chemotherapy and autologous stem cell rescue (HDC) after they had responded to induction chemotherapy. HDC regimens were MiTepa (60 mg/m2 mitoxantrone by continuous intravenous infusion over 3 days plus 300 mg/m2 thiotepa intravenously over 2 hours daily x 3 days) and ICE (12 g/m2 ifosfamide, 1800 mg/m2 carboplatin, 2 g/m2 etoposide; all 3 by continuous intravenous over 4 days). At a median follow up >8 years, the median failure-free survival (FFS) was 13.9 months, median overall survival (OS) 29.1 months, 5-year FFS 12%s and 5-year OS 25%. Thirty-three patients underwent tandem (T) transplants; 27 underwent a single (S) HDC. Median ages for these 2 groups were 45 and 48 years; bone and liver metastases were more prevalent in the T cohort, whereas lung metastases were more prevalent in the S cohort. At a median follow up of 6.5 years for the S group and >9 years for the T group, there were 52 deaths. FFS was better for T: median 15.7 versus 7.7 months (p2 = 0.010) as was OS: median 32.7 versus 17.7 months, 2-year survival 68% versus 41%, and 5-year survival 32% versus 15% (p2 = 0.010). As a group, patients with distant metastatic breast cancer who underwent tandem transplants had a better posttransplant survival than patients who underwent a single HDC.