Improving the efficacy of chemoradiation with targeted agents

Chemoradiation is the standard therapy for the majority of inoperable, locally advanced cancers. Although there is a need to improve chemoradiation efficacy, normal-tissue toxicity limits our ability to give additional chemotherapy or higher doses of radiation. Thus, there is excitement about the addition of molecularly targeted agents, which tend to be less toxic than chemotherapy, to chemoradiation regimens. Unfortunately, initial empiric attempts have not been successful. This review will focus on the evidence that supports rational combinations of targeted agents with chemoradiation, with an emphasis on agents that target the DNA damage response and radiation-induced membrane signaling.