Randomized trial of 3-hour versus 24-hour infusion of high-dose paclitaxel in patients with metastatic or locally advanced breast cancer: National Surgical Adjuvant Breast and Bowel Project Protocol B-26.

Abstract

Paclitaxel is an active drug for the treatment of breast cancer; however, the appropriate duration of administration is unknown. We assessed and compared the response rate, event-free survival, survival, and toxicity of paclitaxel 250 mg/m(2) delivered every 3 weeks as a 3-hour or 24-hour infusion. A total of 563 women with stage IV or IIIB breast cancer were randomized into one of two groups: 279 received 3-hour paclitaxel and 284 received 24-hour paclitaxel. Patients were stratified by age, stage of disease, and prior therapy. A significantly higher rate of tumor response occurred in the first four cycles of therapy in patients who received the 24-hour infusion of paclitaxel (51% v 41%, respectively; P =.025). Tumor response over all cycles was also significantly higher in the group that received 24-hour infusion (54% v 44%, respectively; P =.023). There were no significant differences in event-free survival or survival between the two arms of the study (P =.9 and.8, respectively). No treatment by stage or by age interactions were observed. During the first four cycles of therapy, at least one episode of >/= grade 3 toxicity (excluding nadir hematologic values, alopecia, and weight change) occurred in 45% of patients who received the 3-hour paclitaxel infusion and in 50% of those who received the 24-hour paclitaxel infusion. Febrile neutropenia, >/= grade 3 infection, and >/= grade 3 stomatitis were less frequent, and severe neurosensory toxicity was more frequent in those who received the 3-hour paclitaxel infusion. Ten treatment-related deaths occurred in the first four cycles. Age, stage, and prior chemotherapy did not influence the effect of treatment. When administered as a continuous 24-hour infusion, high-dose paclitaxel results in a higher tumor response rate than when administered as a 3-hour infusion but does not significantly improve event-free survival or survival. Paclitaxel as a 24-hour infusion results in increased hematologic toxicity and decreased neurosensory toxicity.