Prof Pierre-Yves Bondiau speaks to ecancer.tv about his research into the use of CyberKnife to treat lung cancer. This radiosurgery tool allows radiation to be targeted extremely accurately and tracks tumours as they move with the breathing movement of the lung. Because the CyberKnife can accurately deliver high doses of radiation, patients do not require many treatment sessions. CyberKnife is being investigated as a treatment for patients who are not suitable for surgery or as a booster for stage III lung cancer patients following radiotherapy and neo-adjuvant chemotherapy.