DOCETAXEL IN PATIENTS WITH METASTATIC BREAST-CANCER - A PHASE-II STUDY OF THE NATIONAL-CANCER-INSTITUTE OF CANADA - CLINICAL-TRIALS GROUP

Purpose: The National Cancer Institute of Canada-Clinical Trials Group (NCIC-CTG) conducted a phase II study to assess the efficacy and toxi city of docetaxel as first-line chemotherapy in metastatic breast canc er (MBC). Patients and Methods: Fifty-one patients with measurable MBC were studied. Three patients were ineligible and were excluded from a nalysis. The planned dose of docetaxel was 100 mg/m(2) intravenously ( IV) every 3 weeks. Prior adjuvant chemotherapy was allowed if at least 12 months had elapsed from completion of treatment to recurrence. Res ults: The most severe toxicity was granulocytopenia. Ten patients (20. 8%) were hospitalized for febrile neutropenia. The protocol wets amend ed to ct starting dose of 75 mg/m(2) for the last 16 patients. Sixty p ercent of patients experienced hypersensitivity reactions (HSRs). Afte r two protocol amendments, the use of a premedication regimen of oral dexamethasone and IV H-1 and H-2 blockers prevented significant HSRs, Edema developed in 62% of patients and was cumulative, was present in 50% who received greater than 400 mg/m(2), and was not improved by pre medication regimens. Following an independent radiology review, 22 par tial remissions and four complete responses in 47 assessable patients were confirmed (response rate, 55%; 95% confidence interval [CI], 40% to 69%). The response rate for 15 assessable patients registered at 75 mg/m(2) was 40% (95% CI, 16% to 67%); for 32 assessable patients regi stered at 100 mg/m(2), the response rate was 63%, (95% CI, 43% to 78%) . Conclusion: Docetaxel is an active agent in MBC. Its activity as a s ingle agent is comparable to many combination chemotherapy regimens an d is not affected by prior adjuvant chemotherapy. Studies are ongoing to improve its therapeutic index and to incorporate docetaxel in combi nation chemotherapy regimens. (C) 1996 by American Society of Clinical Oncology.