Background: Anthracycline-containing chemotherapy has represented the standard treatment for advanced breast cancer. However, it is sometimes difficult to continue it because of its cumulative cardiac toxicity, and the benefit of adding anthracyclines to the chemotherapy regimen is confined to HER2-overexpressed breast cancer. A non-anthracycline-based novel therapy is necessary to improve the survival and reduce the toxicity.
Methods: We evaluated the tumor response and adverse events of a first-line paclitaxel therapy in advanced or recurrent breast cancer in a variety of practice settings. Patients were to receive paclitaxel tri-weekly (175 mg/m(2)), bi-weekly (120 mg/m(2)) or weekly (80 mg/m(2)) until disease progression or toxicity precluded further treatment. Tumor response and toxicities were evaluated.
Results: Thirty-three patients received a total of 191 cycles (median 5, range 2-19). All patients completed at least two cycles. In 30 patients who were evaluable for response, there were 16 overall responses [53%, 95% confidence interval (CI) 34-72%], including 5 complete responses (17%, 95% CI 3-31%). The median progression-free survival and overall survival were 16 (95% CI 9-24) months and 29 (95% CI 24-36) months, respectively. Overall treatment was well tolerated, and no myelosuppression >grade 3 was reported during this study. A grade 3 dyspnea was noted in one patient, but it recovered spontaneously, and subsequent administration of paclitaxel was successfully given with no specific treatment. No other toxicity greater than grade 3 was demonstrated.
Conclusion: Paclitaxel as a first-line therapy at this dose and schedule is an effective and well-tolerated treatment regimen in Japanese patients with advanced or recurrent breast cancer.