Tandem high-dose chemotherapy in high-risk primary breast cancer: A multivariate analysis and a matched-pair comparison with standard-dose chemotherapy

Stem cell-supported high-dose chemotherapy (HDCT) is currently being evalua ted in patients with high-risk primary breast cancer (HRPBC), as defined by extensive axillary lymph node involvement. Conclusive results from randomi zed studies with sufficient patient numbers and follow-up are pending. We r etrospectively analyzed 144 HRPBC patients enrolled in a single-arm trial o f tandem HDCT at the University of Heidelberg to evaluate the prognostic va lue of nodal ratio, HER2/neu status, and cytokeratin-positive bone marrow c ells and to compare the outcomes of these patients with those of a conventi onally treated control group of 91 patients matched by nodal ratio, tumor s ize, combined hormone-receptor status, and HER2/neu status. The tandem HDCT regimen consisted of 2 cycles of induction chemotherapy followed by 2 cycl es of blood stem cell-supported high-dose ifosfamide, 12 g/m(2); carboplati n, 900 mg/m(2); and epirubicin, 180 mg/m2. Conventionally treated patients received a regimen containing anthracycline without taxanes (52 patients) o r CMF (cyclophosphamide, methotrexate, and 5-flurouracil; 39 patients). Wit h a median follow-up of 3.8 years, disease-free, distant disease-free, and overall survival rates were 62%, 65%, and 84%, respectively. In univariate analysis, besides the hormone receptor status (P = .007), HER2/neu overexpr ession was the strongest predictor of earlier death (P = .017). In multivar iate analysis, a nodal ratio of greater than or equal to0.8 was found to be the only independent predictor of relapse (relative risk [RR] = 2.09; 95% confidence interval [CI], 1.21-3.60; P = .008) and only the absence of horm one receptors was associated with earlier death (RR = 3.59; 95% CI, 1.45-8. 86; P =.006). Despite a trend toward later distant relapse after HDCT compa red with standard-dose chemotherapy with a median follow-up of 3 years (P = .059), thus far, matched-pair analysis has not demonstrated significantly better survival rates after HDCT in all matched patients (P = .786) or in t he subgroups of anthracycline-treated patients and patients with and withou t overexpression of HER2/neu. So far, the follow-up time has been too short to draw definite conclusions; however, patients with a nodal ratio of grea ter than or equal to0.8, receptor-negative tumors, or HER2/neu overexpressi on are at high risk for relapse and death, irrespective of the kind of adju vant chemotherapy.