Background: Combinations of anthracyclines, taxanes and gemcitabine have shown high activity in breast cancer. This trial was designed to evaluate a modified combination regimen as primary chemotherapy. Non-pegylated liposomal doxorubicin (NPLD) was used instead of conventional doxorubicin to improve cardiac safety. Gemcitabine was given 72 h after NPLD and docetaxel as a prolonged infusion over 4 h in order to optimize synergistic effects and accumulation of active metabolites.
Patients and methods: Forty-four patients with histologically confirmed stage II or III breast cancer were treated with NPLD (60 mg/m(2)) and docetaxel (75 mg/m(2)) on day 1 and gemcitabine as 4-h infusion (350 mg/m(2)) on day 4. Treatment was repeated every 3 weeks for a maximum of six cycles. All patients received prophylactically recombinant granulocyte colony-stimulating factor. Patients with axillary lymph node involvement after primary chemotherapy received adjuvant treatment with cyclophosphamide, methotrexate and fluorouracil.
Results: The clinical response rate was 80%, and complete remissions of the primary tumor occurred in 10 patients (25%). Breast conservation surgery was performed in 19 out of 20 patients (95%) with an initial tumor size of less than 3 cm and in 14 patients (70%) with a tumor size <or=3 cm. Seven patients had histologically confirmed complete responses accounting for a pCR rate of 17.5%. Expression of Ki--67 was the most important predictive parameter for response with high 38.9% breast pCR rate in patients with elevated Ki--67 expression. Although the predominant toxicity was myelosuppression with grade 3/4 neutropenia in 61% of patients few neutropenic complications resulted. Non-hematological toxicity was generally moderate with grade 3 or 4 toxicity in 10.0% of cycles. Most common non-hematologic toxicities were nausea, vomiting, alopecia, mucositis, asthenia and elevation of liver enzymes.
Conclusion: The evaluated schedule provides a safe and highly effective combination treatment for patients with early breast cancer, which is suitable for phase III studies.