Aim of the study: The study examined the response rate, response duration and toxicity of vinorelbine and fluorouracil or vinorelbine alone in pretreated metastatic breast cancer.
Material and methods: Between June 2001 and September 2009, a group of 103 patients with locally advanced or metastatic breast cancer, who had progressed after anthracycline/taxane chemotherapy, was treated with a vinorelbine-based regimen. The treatment consisted of vinorelbine 25 mg/m(2) and 5-fluorouracil (5-FU) 500 mg/m(2) administered intravenously on days 1 and 8 of each cycle (53 patients) or vinorelbine alone at a dose of 30 mg/m(2) on day 1 and 8 of the cycle, every 3 weeks (50 patients). Patients received chemotherapy as a second or further line of therapy. Treatment was continued until disease progression or unacceptable toxicity. The median age of patients treated with vinorelbine with 5FU was 54 years (range 38-76), and 55.5 years (range 38-73) in the group receiving vinorelbine monotherapy. A total of 417 cycles of chemotherapy were administered - 177 cycles of vinorelbine with 5-FU and 137 cycles of vinorelbine monotherapy. Patients were treated for a median of 4 cycles (range: 1 to 11 cycles). The evaluation of treatment effect was possible in 93 patients (10 patients received only one treatment cycle).
Results: The overall response rate (ORR) was 17% (7), including 2 (4%) complete responses (CR) and 5 (10.5%) partial responses (PR). Stable disease (SD) was observed in 50% of patients receiving vinorelbine with 5-FU (24 patients). In a group receiving vinorelbine alone the ORR was 20% (9), including 9 PR (20%) and 16 SD (35.5%). The median time to progression (TTP) for the entire group was 18 weeks (95% CI), 22 weeks among patients treated with vinorelbine with 5-FU and 16 weeks for a second group. The most common hematologic adverse events were neutropenia (20% of cycles) and thrombocytopenia (4%), with grade 3/4 incidence of 8% and 1.5% [according to National Cancer Institute Common Toxicity Criteria (NCI CTC)]. Nausea and vomiting were the most frequent non-hematologic forms of toxicity, occurring in 13% of cycles. The doses of cytotoxics were reduced in 26 (25%) cases. There were no treatment-related deaths.
Conclusions: Vinorelbine alone or in combination with 5-FU is an effective and safe treatment for pretreated advanced/ metastatic breast cancer patients. The combination of vinorelbine with 5-FU appears to be a more efficacious regimen than vinorelbine alone.
Keywords: breast cancer; chemotherapy; metastasis; winorelbine.