Activity and toxicity of docetaxel (Taxotere) in women with previously treated metastatic breast cancer.

BACKGROUND

Metastatic breast cancer is a major cause of cancer death in Australian women. Docetaxel is a new cytotoxic drug that has shown promise in the treatment of metastatic breast cancer in patients who have previously received other chemotherapy, particularly an anthracycline, and has recently been approved for marketing in Australia.

AIM: To report the first Australian experience with docetaxel in a group of women with metastatic breast cancer.

METHODS

Patients with progressive metastatic breast cancer who had previously received other chemotherapy were treated with docetaxel 75 mg/m2 or 100 mg/m2 given as a one hour infusion every three weeks. All patients received oral dexamethasone for five days starting 24 hours prior to docetaxel as prophylaxis against fluid retention. The patients' response to docetaxel and toxicity were assessed by standard criteria.

RESULTS

Twenty-six patients were treated. The major toxicity was neutropenia with 92% of patients experiencing at least one episode of grade 4 (absolute neutrophil count < 0.5 x 10(9)/L) neutropenia. Hospital admission for febrile neutropenia occurred in 44% of patients with one death from sepsis. Cumulative fluid retention was observed but in only one patient was it dose-limiting. Apart from alopecia, other toxicities were infrequent and rarely serious. In 23 patients assessable for response, there were 11 partial responses (48%). Three other patients whose disease could not be assessed for response had clinical improvement. The median survival of all patients treated was eight months.

CONCLUSIONS

The response rate observed with docetaxel is comparable to that seen in trials in the United States and Europe and confirms the high activity of this new cytotoxic agent. Neutropenia is the major toxicity, and consideration should be given to the use of prophylactic oral antibiotics or colony stimulating factors to try and prevent febrile episodes. Clinicians will need to balance the benefits, toxicities, and cost of docetaxel in determining the appropriateness of its use in their patients.