Whole-Breast Irradiation with or without a Boost for Patients Treated with Breast-Conserving Surgery for Early Breast Cancer: 20-Year Follow-Up of a Randomised Phase 3 Trial

Since the introduction of breast-conserving treatment, various radiation doses after lumpectomy have been used. This randomised trial compared standard whole-breast radiotherapy (WBRT) versus WBRT plus a boost of 16 Gray (Gy) to the tumour bed. Outcomes included overall survival, local control and fibrosis. All patients had stage I and II breast cancer treated with breast-conserving treatment. Here, 20-year follow-up results are presented. This is the key study to demonstrate the value of boost radiotherapy for high local recurrence risk breast cancer.