Phase II study of pegylated liposomal doxorubicin (Caelyx) and docetaxel as first-line treatment in metastatic breast cancer.

BACKGROUND: The aim of this study was to determine the activity and safety of pegylated liposomal doxorubicin (PLD; Caelyx) and docetaxel combination as first-line treatment in patients with metastatic breast cancer (MBC). PATIENTS AND METHODS: Forty-four patients with a median age of 63 years were treated with PLD 30 mg/m(2) (day 1) and docetaxel 75 mg/m(2) (day 2) every 3 weeks for six cycles. Recombinant human Granulocyte Colony-Stimulating Factor (rhG-CSF) could be used in patients with grade > or =3 neutropenia after the first cycle. RESULTS: Forty-two of 44 patients were assessable for response. The response rate (RR) was 64.3% (95% confidence interval 49.8% to 78.8%). Six patients (14.3%) achieved complete response (complete disappearance of all measurable and assessable disease lasting at least 4 weeks, no new lesions, no disease-related symptoms), partial response was observed in 21 patients (50%) > or =50% decrease of measureable disease lasting at least 4 weeks, no progression of assessable disease, no new lesions, no disease-related symptoms), eight patients had stable disease and seven patients progressive disease. Median disease-free and overall survival were not reached, but were in excess of 17 months (range 6-17 months). Twenty of the patients had received previous adjuvant chemotherapy (10 with epirubicin-containing regimen with a median cumulative dose of 400 mg/m(2)). Grade > or =3 neutropenia occurred in 18.4% and neutropenic fever in 9% of patients. Palmar-plantar erythrodysesthesia was observed in four patients. Dose reduction was necessary in seven patients. Two patients discontinued treatment: one due to prolonged grade 3-4 neutropenia and one due to neurotoxicity. No treatment-related deaths occurred. CONCLUSIONS: The combination of PLD and docetaxel achieved high RRs with acceptable toxicity as first-line treatment in MBC.

Evidence for in vivo synergism between docetaxel and gemcitabine in patients with metastatic breast cancer.

BACKGROUND: The docetaxel and gemcitabine combination is active as salvage therapy in taxane-resistant/refractory patients with metastatic breast cancer (MBC). We conducted a phase II study to determine if this activity is due to an in vivo synergistic effect. PATIENTS AND METHODS: Women with measurable MBC, who were refractory or resistant to docetaxel monotherapy as first- or second-line treatment, were enrolled. Patients with progressive disease (PD) or stable disease (SD) after receiving at least four cycles of docetaxel received gemcitabine 900 mg/m(2) on days 1 and 8 plus docetaxel 100 mg/m(2 )on day 8, every 3 weeks. Granulocyte colony-stimulating factor could be used prophylactically in patients who experienced grade 3/4 neutropenia after the first cycle. RESULTS: Between January 1999 and March 2002, 173 courses of docetaxel and gemcitabine were administered to 50 patients. The median number of metastatic sites was two (range one to three). Forty-six percent of patients responded (three complete responses, 20 partial responses), whereas 28% had SD and 26% had PD. The median duration of response was 6.1 +/- 2.4 months. The median time to disease progression was 7.5 months (range 1-25) and the overall median survival was 15 months (range 3-57). Neutropenia was the only National Cancer Institute Common Toxicity Criteria grade 4 toxicity (in seven patients). Hematological grade 3 toxicities included neutropenia in 12 patients, thrombocytopenia in seven and anemia in one, while non-hematological toxicities were mild and manageable. CONCLUSIONS: The high overall response rate of the docetaxel plus gemcitabine combination after docetaxel failure in patients with MBC can be attributed to an in vivo synergism between the two drugs. These data warrant confirmation in a randomized study.