Two weekly vinorelbine: administration in patients who have received at least two prior chemotherapy regimes for advanced breast cancer.

This study examined the response to and toxicity of two weekly vinorelbine administration in patients with at least two prior chemotherapeutic treatments for advanced breast cancer. This single centre study enrolled 20 patients, 19 of whom had received prior taxane treatment for advanced breast cancer. Taxane treatment was in the form of docetaxel for all but 1 patient who had received paclitaxel. All patients had received two or more prior chemotherapeutic regimes for advanced breast carcinoma, including anthracyclines (epirubicin) in 19 patients. Vinorelbine 25 mg/m2 two weekly was given for 6 months, until disease progression or toxicity precluded further treatment. 5 earlier studied patients started vinorelbine at 25 mg/m2/week; all changed to the two weekly schedule, limiting the incidence and severity of neutropenia. 7 partial responses (PRs) out of 20 assessable patients (35% overall response rate, 95% confidence interval 15-59%) were noted, all PRs occurring in taxane pretreated patients. The median duration of response was 4 months whilst the median time to progression was 2.75 months. Overall, there were 7 neutropenic events (35%) of 2 week median duration, spanning common toxicity criteria (CTC) grades 1-3 in severity. 5 neutropenia cases (25%) occurred in patients whilst on two weekly vinorelbine. 2 cases (10%) required granulocyte colony stimulating factor support, 1 having had febrile neutropenia (52%). One case of thrombocytopenia, neurotoxicity and nausea (each CTC grade 1) were recorded. Although this study involves a small number of cases, these preliminary results suggest that two weekly vinorelbine is effective in heavily pretreated (including taxane pretreated) advanced breast carcinoma. Response is comparable with that of traditionally used weekly regimes, with markedly less toxicity.