Accelerated-intensified Cyclophosphamide, Epirubicin, and Fluorouracil (CEF) compared with standard CEF in metastatic breast cancer patients: Results of a multicenter, randomized phase III study of the Italian gruppo oncologico nord-quest-mammella inter gruppo group

Purpose: To evaluate whether an accelerated-intensified cyclophosphamide, epirubicin, and fluorouracil (CEF) chemotherapy regimen with the support of granulocyte colony-stimulating factor (G-CSF) induces a higher activity and efficacy compared with standard CEF in metastatic breast cancer patients. Patients and Methods: Stage IV breast cancer patients were randomized to receive as first-line chemotherapy either standard CEF (cyclophosphamide 600 mg/m², epirubicin 60 mg/m², and fluorouracil 600 mg/m²) administered every 21 days (CEF21) or accelerated-intensified CEF (cyclophosphamide 1,000 mg/m², epirubicin 80 mg/m², and fluorouracil 600 mg/m²) administered every 14 days (HD-CEF14) with the support of G-CSF. Treatment was administered for eight cycles. Results: A total of 151 patients were randomized (74 patients on the CEF21 arm and 77 on the HD-CEF14 arm). In both arms, the median number of administered cycles was eight. The dose-intensity actually administered was 93% and 86% of that planned, in CEF21 - and HD-CEF14-treated patients, respectively. Compared with the CEF21 arm, the dose-intensity increase in the HD-CEF14 arm was 80%. Both nonhematologic and hematologic toxicities were higher in the HD-CEF14 arm than in the CEF21 arm. During chemotherapy, four deaths occurred in the HD-CEF14 arm. No difference in overall response rate (complete plus partial responses) was observed: 49% and 51% in the CEF21 and HD-CEF14 arms, respectively (P = .94). A slightly nonstatistically significant higher percentage of complete response was observed in the HD-CEF14 arm (20% v 15%). No difference in efficacy was observed. The median time to progression was 14.3 and 12.8 months in the CEF21 and HD-CEF14 arms, respectively (P = .69). Median overall survival was 32.7 and 27.2 months in the CEF21 and HD-CEF 14 arms, respectively (P = .16). Conclusion: In metastatic breast cancer patients, an 80% increase in dose-intensity of the CEF regimen, obtained by both acceleration and dose intensification, does not improve the activity and the efficacy compared with a standard dose-intensity CEF regimen.