Paclitaxel administered weekly in patients with docetaxel-resistant metastatic breast cancer: a single-center study.
OBJECTIVE
We evaluated retrospectively the efficacy and toxicity of paclitaxel in patients with docetaxel-resistant metastatic breast cancer.


METHODS
Paclitaxel (80 mg/m2) was administered weekly to 44 patients who had previously received chemotherapy regimens for metastatic breast cancer. All patients had progressive disease in spite of having received docetaxel therapy.


RESULTS
Treatment was repeated until there was evidence of disease progression. Objective responses were obtained in 14 of 44 assessable patients (31.8%; 95% confidence interval, 17.5-46.1). Fourteen patients had partial responses; none responded completely. Seven of 14 responders had primary resistance to docetaxel therapy. The median duration of response was 6.1 months (range, 2.1-12.7). The median time to progression was 5.0 months. Clinically severe adverse events (grade 3 or 4) included neutropenia (27.2%), leukopenia (25.0%), neuropathy-sensory (13.6%), febrile neutropenia (6.8%), anemia (2.2%), constipation (2.2%), and edema (2.2%). Treatment was generally well tolerated and could be continued on an out-patient basis.


CONCLUSIONS
Weekly paclitaxel is effective in patients with docetaxel-resistant metastatic breast cancer. This observation suggests partial cross-resistance between paclitaxel and docetaxel. There was no evidence for additive cumulative toxic effects of the two taxanes.
Sawaki
Masataka
M
Department of Medical Oncology, Cancer Institute Hospital and Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Tokyo, Japan. sawapi@qc4.so-net.ne.jp
Ito
Yoshinori
Y
Hashimoto
Daigo
D
Mizunuma
Nobuyuki
N
Takahashi
Shunji
S
Horikoshi
Noboru
N
Tada
Keiichiro
K
Kasumi
Fujio
F
Akiyama
Futoshi
F
Sakamoto
Goi
G
Imai
Tsuneo
T
Nakao
Akimasa
A
Hatake
Kiyohiko
K
D000328:Adult; D000368:Aged; D000972:Antineoplastic Agents, Phytogenic / Q000008:administration & dosage*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D018450:Disease Progression; D000077143:Docetaxel; D004334:Drug Administration Schedule; D019008:Drug Resistance, Neoplasm; D005260:Female; D006801:Humans; D008875:Middle Aged; D017239:Paclitaxel / Q000008:administration & dosage*; D012189:Retrospective Studies; D043823:Taxoids / Q000627:therapeutic use; D016896:Treatment Outcome
D000972:Antineoplastic Agents, Phytogenic; D043823:Taxoids; D000077143:Docetaxel; D017239:Paclitaxel