Purpose: In this phase II study, we explored tolerability and activity of vinorelbine administered according to a dose-dense weekly schedule with hematopoietic growth factor support in pretreated, advanced breast cancer patients.
Patients and methods: From January 1994 to March 1996, 40 patients with metastatic breast cancer, pretreated with at least one prior anthracycline-containing regimen, were entered into the study.
Patient characteristics: median age 53 years (range 32-70); ECOG performance status 0-1: 34 patients, 2: 6 patients; dominant visceral metastatic disease: 15 patients, dominant non-visceral: 25; anthracycline-refractory/resistant: 2 patients, sensitive: 38 patients. Six patients were treated as first-line therapy for metastatic disease and 34 in second- or subsequent lines. All patients received vinorelbine at the dose of 25 mg/m2/week as a short intravenous infusion, together with routine antiemetic medication. Granulocyte-colony stimulating factor (Lenograstim) at the dose of 150 microg/m2 subcutaneously on day 3 was included in the treatment schedule.
Results: The median number of treatment weeks was 23 (range: 4-24), with a delivered dose-intensity (DDI) of 23.8 mg/m2/week (range: 18.7-25, 95.2% of projected dose-intensity). Toxicity was mild, with non-complicated neutropenia being the main toxicity observed (grade 3-4 in 25% of the patients but only 2% of treatment weeks). Overall response rate was 52.5%, with complete responses in 12.5% of patients. Median duration of the response and median time to progression were 10 and 9 months, respectively. Median overall survival was 19 months.
Conclusion: Dose-dense weekly vinorelbine is safe and effective with minimal toxicity in pretreated advanced breast cancer patients.