Introduction
Patients with node-negative breast cancer (NNBC) often receive postoperative adjuvant radiotherapy as a means of eradicating any micrometastatic deposits which may still remain in the breast following surgical resection. However, approximately one third of these patients relapse and a subgroup shows increased morbidity or reduced survival. There is a need to define other criteria in these patients which could be used to optimise treatment. The angiogenic factor, vascular endothelial growth factor (VEGF), correlates with tumour vascularity and has been proposed as a predictor of overall survival (OS) in breast cancer patients. The degree of tumour vascularity may also be important for effective radiotherapy; this is thought to be less effective in poorly vascularised tumours.