MODEL RELEASED. Radiologist examining a series of mammograms arranged against a lightbox. Mammography is a special type of X-ray image that reveals fine details of soft tissues in the breast. The technique is the principal means of screening women for breast cancer. A radiologist, a doctor specialising in X-ray medicine, is able to distinguish between cancerous tumours and other benign conditions such as cysts, by careful examination of mammograms. Small tumours detected at an early stage may sometimes be treated in a conservative manner without resort to a mastectomy, the removal of the whole breast. Photographed at King's College Hospital, London.