Outcomes of Palliative Weekly Low-Dose Gemcitabine-Cisplatin Chemotherapy in Anthracycline- and Taxane- Pretreated Metastatic Breast Cancer Patients

PURPOSE: The combination of gemcitabine and cisplatin (GP) has been shown to be safe and efficacious for patients with metastatic breast cancer (MBC), pretreated with anthracyclines and taxanes. We assessed the efficacy and safety of weekly low-dose GP in patients with MBC. METHODS: We collected clinicopathological data from MBC patients who had been treated with gemcitabine, 800 mg/m(2) plus cisplatin, 30 mg/m(2) intravenously, on days 1 and 8 every 3 weeks, between January 2001 and November 2011 in Korea. RESULTS: The analysis included 294 patients previously treated anthracycline-xand taxane-based chemotherapies prior to GP (median age, 48 years [range, 28-78 years]; median follow-up duration, 63.9 months). Seventeen patients (5.8%) discontinued GP because of toxicities. The median progression-free survival (PFS) was 3.9 months (95% confidence interval [CI], 3.394.4 months) and the median overall survival (OS) was 27.7 months (95% CI, 17.6-37.8 months) months. Statistically significant factors for PFS were performance status (Eastern Cooperative Oncology Group, ≥2 vs. <2; hazard ratio [HR], 1.37; 95% CI, 1.02-1.85; p=0.037), distant disease-free interval (DDFI; ≤2 years vs. >2 years; HR, 1.66; 95% CI, 1.28-1.95, p<0.001), time interval from the diagnosis of metastasis to GP therapy (≤1 year vs. >1 year; HR, 1.48; 95% CI, 1.13-1.95, p<0.001), and presence of brain metastasis (HR, 1.47; 95% CI, 1.03-2.10; p=0.031). Similarly, DDFI (≤2 years vs. >2 years; HR, 2.07; 95% CI, 1.36-3.14; p<0.001) and the presence of brain metastasis (HR, 2.14; 95% CI, 1.27-3.61; p=0.004) were important factors for OS after GP treatment. CONCLUSION: Weekly low-dose GP chemotherapy appears safe and effective for heavily pretreated MBC patients.