Immunological interactions in radiotherapy-opening a new window of opportunity.

After a span of significant developments & advances we have reached a plateau in all the oncological disciplines in last decade. Escalation of dose of radiotherapy (RT) became possible with emergence of intensity modulated radiotherapy (IMRT) and image guided radiotherapy (IGRT). Different radiosensitizing agents starting from conventional cytotoxic drugs to hypoxic radiosensitizers have been tried to increase the effect of RT. However technological advancement hasn't been translated into significant clinical benefits. Exploiting the immune system to enhance the effect of RT is a relatively new concept and a fast growing area in the field of oncology. RT cannot longer be considered as a localized treatment, but rather as a systemic weapon for solid tumors. The phenomenon of abscopal effect, meaning the action of RT upon distant 'out-of-field' foci of malignancies has been a major focus of recent research, and holds great promise for the future. In this review article we are going to discuss the immunological interactions in RT and its promising clinical implications.