Interventional Oncology is a growing subspecialty amongst radiologists whose techniques include occluding blood supply to a tumour to prevent haemorrhage (embolization); guiding fine needles into them under imaging control, then using radiofrequency or microwaves or freezing for ABLATION. This method is used in kidney, lung and liver cancer often to reduce the size of a tumour to allow for successful surgery. Chemotherapy can be precisely targeted by delivering it directly into the tumour through an artery (transarterial chemoembolization) and a similar method can be used to place radioactive microspheres at a tumour site.