Radiotherapy plays an essential role in the treatment of more than half of all patients with cancer. In recent decades, advances in devices that deliver radiation and the development of treatment planning software have helped radiotherapy attain precise tumour targeting with minimal toxicity to surrounding tissues. Simultaneously, as more targeted drug therapies are being brought into the market, there has been significant interest in improving cure rates for cancer by adding drugs to radiotherapy to widen the therapeutic window, the difference between normal tissue toxicity and treatment efficacy. The development of new combination therapies will require judicious adaptation of preclinical models that are routinely used for traditional drug discovery. Here we highlight the strengths and weaknesses of each of these preclinical models and discuss how they can be used optimally to identify new and clinically beneficial drug–radiotherapy combinations.

放射治疗在一半以上的癌症患者的治疗中起着至关重要的作用。近几十年来，放射治疗设备的进步和治疗计划软件的开发帮助放射治疗实现了精确的肿瘤靶向，同时对周围组织的毒性最小。同时，随着更多靶向药物疗法进入市场，人们对通过在放疗中添加药物以扩大治疗窗口、正常组织毒性和治疗效果之间的差异来提高癌症治愈率产生了浓厚的兴趣。新组合疗法的开发将需要对常规用于传统药物发现的临床前模型进行明智的调整。