A phase II trial of paclitaxel (Taxol) as first line treatment in advanced breast cancer.

Paclitaxel (Taxol) is a natural product with a broad spectrum of activity against various solid tumors. This report includes nineteen patients with advanced breast cancer who have not previously received chemotherapy for metastatic disease. Fifteen patients had received adjuvant chemotherapy, eight of which were doxorubicin based. Patients were treated with 135 mg/m2 over 24 hours by continuous infusion given every 21 days. There were 2 complete and 4 partial responses for an objective response rate of 32% (95% C.I.: 14%, 57%) and eight patients or 42% with stable disease. Three of eight patients (38%) who had received adjuvant doxorubicin did respond to paclitaxel. Responses occurred in lung, liver, and soft tissue. The primary toxicity was hematologic with 13 hospitalizations for febrile neutropenia in 180 cycles (7%). Paclitaxel has moderate activity in a small number of patients with metastatic breast cancer at the dose of 135 mg/m2 over 24 hours in this study.