Clinical experience of weekly paclitaxel-based treatment as preoperative chemotherapy for patients with primary breast cancer.

BACKGROUND: Paclitaxel is an effective agent in the treatment of metastatic breast cancer. The aim of this study was to evaluate the safety and efficacy of weekly paclitaxel-based preoperative chemotherapy in patients with large operable breast cancer.

METHODS: Patients initially received paclitaxel as a 3-hour infusion at 175 mg/m2. Three weeks after initial administration, two cycles of three weeks of paclitaxel 80 mg/m2 over a 1 hour infusion followed by a one week break were given. Of 22 patients, 9 had stage II (tumor diameter greater than 3 cm), 4 stage III A, 7 stage III B, and 2 stage IV (with ipsilateral supraclavicular lymph node metastasis) cancer, respectively.

RESULTS: Excluding stage IV patients, the overall response rate to paclitaxel chemotherapy was 80%. Four of the 20 patients (20%) showed a clinical complete response (cCR). Two of these showed pathologic complete response and the other 2 had only the ductal component remaining. The primary tumor response and axillary lymph node downstaging following preoperative chemotherapy tended to be related in 16 patients with clinically positive nodes. Breast conserving surgery was performed as a result of downstaging in the 9 stage II patients. Grade 3 neutropenia occurred in one patient when 175 mg/m2 of paclitaxel was administered, but no serious side effects developed during the weekly administration of paclitaxel.

CONCLUSION: The use of weekly paclitaxel-based preoperative chemotherapy appears to yield a significant anti-tumor effect without inducing serious drug-related adverse effects. Furthermore, the effectiveness of this treatment appears to result in a higher frequency of breast conserving surgery.