Chemotherapy and irradiation interaction.

The combination of chemotherapeutic drugs with radiation therapy has perhaps been one of the most promising strategies for current cancer radiotherapy practice, and has a strong biologic rationale. Concurrent chemoradiotherapy has been shown to improve survival and locoregional control of various cancers compared with radiotherapy alone. This article reviews the biologic rationale and principles fundamental to the use of chemoradiotherapy, and discusses mechanistic interactions between drugs and radiation, the knowledge of which is essential in developing optimal treatment strategies. Chemotherapeutic agents, particularly those shown to augment the radiation response of tumors, will be reviewed, and novel compounds and some of the exciting emerging strategies for chemoradiotherapy will be presented.