The ADEBAR trial: Final toxicity analysis of a phase III study evaluating the role of docetaxel in the adjuvant therapy of breast cancer patients with extensive lymph node involvement

Abstract

585 Background: Taxane based adjuvant chemotherapy has been established as standard treatment in node-positive breast cancer. However, toxicity concerns of combined anthracycline-taxane regimens have compromised its acceptance. We analyzed the toxicity of a sequential anthracycline-taxane chemotherapy compared to a conventional anthracycline regimen. Patients and Methods: ADEBAR was a multicenter phase III trial (n=1,502) to evaluate whether breast cancer (BC) pts with > 3 axillary lymph metastases benefit from a sequential anthracycline-docetaxel regimen (E90C-D: 4 cycles epirubicin [E] 90 mg/m2 plus cyclophosphamide [C] 600 mg/m2 q21 days followed by 4 cycles docetaxel [D] 100mg/m2 q21 days) compared to dose-intensive anthracycline-containing polychemotherapy (FE120C: 6 cycles E 60 mg/m2 d 1+8, 5-FU 500mg/m2 d 1+8 and C 75 mg/m2 d 1–14, q4 weeks). We present the final toxicity analysis. Results: Complete toxicity data were available from 1,338 pts. Treatment was stopped prematurely in 3.7% of the pts in the E90C-D arm and in 8.0% in the FE120C arm due to toxicity (p=0.0009). Antibiotic treatment was given in 10.4% (E90C-D) vs. 19.7% (FE120C), G-CSF support in 39.2% vs 61.4 % and erythropoietin stimulation in 8.7% vs. 20.0%, respectively (p<0.0001). Hematologic and non-hematological grade 3–4 toxicities are summarized in the table . In summary, haematological toxicity (leucopenia, infection thrombocytopenia, anemia) was significantly greater in the FE120C-arm. Skin toxicity, edema and vomiting occurred significantly more often in pts treated with E90C-D. Conclusion: Different toxicity profiles given, overall toxicity of a sequential anthracycline-taxane regimen is not necessarily greater than that of an adequately dosed anthracycline chemotherapy, which needed to be interrupted more frequently due to toxicity. [Table: see text] No significant financial relationships to disclose.