Accelerated partial breast irradiation: technically feasible but who will benefit?

Modern breast cancer radiotherapy aims to increase uncomplicated cure rates. A priority is reduction of late effects which include chronic chest wall or breast pain, poor cosmesis, and cardiac toxicity. As breast screening detects early cancers we may be able to safely restrict irradiation postlumpectomy to the tumour bed with a margin, defining a 'partial breast' target volume for treatment. Differing technical approaches to partial breast irradiation are being evaluated in phase III studies with standard whole breast irradiation. These include intra-operative single doses, hypo-fractionated accelerated brachytherapy, and LINAC (linear accelerator)-based three-dimensional external beam therapy.