Results and long term follow-up for 1581 patients with metastatic breast carcinoma treated with standard dose doxorubicin-containing chemotherapy: a reference

BACKGROUND: The authors report results and long term follow-up for 1581 patients with metastatic breast carcinoma treated with doxorubicin-containing combination chemotherapy at a single institution; this report is meant to serve as a reliable reference for single-arm studies of newer therapies in this patient population. METHODS: Prospectively collected data from 18 successive doxorubicin-containing protocols for the treatment of metastatic breast carcinoma were evaluated. RESULTS: The response rate was 65.0% (95% confidence interval CI]: 62.5-67.3%), complete response (CR) rate was 16.6% (95% CI: 14.8-18.6%), and partial response (PR) rate was 48.5% (95% CI: 46.0-50.9%). Median progression free survival (PFS) was 11.5 months (95% CI: 10.9-12.3 months) and median overall survival (OS) was 21.3 months (95% CI: 20.3-22.7 months). Survival correlated with response to therapy; median PFS and OS were 22.4 and 41.8 months, respectively, for the patients who achieved CR (n=263) and 14 and 24.6 months, respectively, for PR patients (n=766). The median OS of patients who had progressive disease during chemotherapy was 3.8 months. The response rate, PFS and OS correlated with number of organs involved and especially with tumor burden. Patients with hormone receptor-positive tumors had a similar response rate to that of patients with hormone receptor negative tumors but had significantly longer PFS (medians of 14.3 and 8.7 months, respectively) and OS (medians of 28.6 and 18.1 months, respectively). CONCLUSIONS: In patients with metastatic breast carcinoma, doxorubicin-containing chemotherapy had a response rate of 65% and a CR rate of 16.6%. PFS and OS were 11.5 months and 21.3 months, respectively, for all responders and 22.4 months and 41.8 months, respectively, for those who had CR.