Sequencing of Chemotherapy and Radiotherapy in Adjuvant Breast Cancer

OBJECTIVES: Compare the effects of synchronous vs sequential adjuvant chemotherapy and radiotherapy on local recurrence, disease-free and overall survival, and treatment delay in women with early-stage breast cancer. Compare the safety of these regimens, in terms of dose intensity and toxicity, in this patient population. Compare the quality of life and cosmetic outcome in patients treated with these regimens. OUTLINE: This is a randomized, multicenter study. Patients are stratified according to clinical oncologist, axillary clearance (yes vs no), radiotherapy boost intent (boost vs no boost), and chemotherapy intent (cyclophosphamide, methotrexate, and fluorouracil [5-FU] vs anthracycline-containing regimen). Patients are randomized to one of two treatment arms. Patients receive any chemotherapy regimen that includes cyclophosphamide, methotrexate, and 5-FU. Some regimens may also include epirubicin, doxorubicin, mitoxantrone, and/or mitomycin. Chemotherapy repeats every 3 weeks for 4-8 courses. Arm I (synchronous chemoradiotherapy): Patients receiving synchronous therapy receive any of the above chemotherapy regimens plus daily radiotherapy between courses 2 and 3 OR courses 5 and 6 of chemotherapy. Radiotherapy is administered for 3-5 weeks. Arm II (sequential chemoradiotherapy): Patients receiving sequential therapy receive any of the above chemotherapy regimens followed by daily radiotherapy beginning after completion of all chemotherapy (after course 6 or 8). Radiotherapy is administered for 3-5 weeks. Treatment in both arms continues in the absence of disease progression or unacceptable toxicity. Quality of life is assessed before chemotherapy, 2-3 weeks after the completion of all treatment, and then at 1, 2, and 5 years. Patients are followed annually for 10 years. Peer Reviewed and Funded or Endorsed by Cancer Research UK PROJECTED ACCRUAL: A total of 2,250 patients (1,125 per treatment arm) will be accrued for this study.