Activity of first-line epirubicin and paclitaxel in metastatic breast cancer is independent of type of adjuvant therapy

To evaluate the impact of prior adjuvant chemotherapy on response rate (RR), progression-free (PFS) and overall survival (OS) of metastatic breast cancer patients treated with epirubicin/paclitaxel (ET) regimens. In all, 291 patients enrolled in five studies in metastatic breast cancer were analysed: 101 (35%) were chemonaive, 109 (37%) had received adjuvant CMF and 81 (28%) adjuvant anthracyclines. Response rate to ET was 66%. Response rate was 63% for cyclophosphamide plus methotrexate plus 5-fluorouracil (CMF), 67% for prior anthracyclines and 68% in chemonaive patients (P = 0.5). By multivariate analysis, adjusted odds ratio for response was 0.81 (95% CI:0.37-1.79) for CMF and 0.92 (95% CI 0.43-2.01) for anthracyclines (P = 0.86). The CR rates were 14% for both CMF and anthracyclines and 22% for chemonaive patients (P = 0,2). By multivariate analysis, the relative odds of CR for CMF or anthracyclines were 0.40 and 0.39 as compared to chemonaive patients (P = 0.036). The median PFS was 11.0 months for prior CMF, 10.2 months for anthracyclines and 12.5 months in chemonaive patients (P = 0.33). In multivariate Cox's model, a nonsignificant increase in the risk of progression was seen in patients treated with adjuvant CMF or anthracyclines. The median OS was 23.8 months for CMF, 20.2 months for anthracyclines and 27.5 months in chemonaive patients (P = 0.61). The same, nonsignificant, association was seen in multivariate analysis. The ET regimens provide satisfactory results in metastatic breast cancer, regardless of previous adjuvant chemotherapy.