Clinical evidence for synergy between immunotherapy and radiotherapy (SITAR).

Previous preclinical and clinical trials have shown promising antitumour activity and toxicity profile when employing the 'Synergy between Immunotherapy and Radiotherapy' (SITAR) strategy. Approximately, one in seven radiation therapy studies currently recruiting is investigating SITAR. This article reviews the range of cancers known to respond to immunotherapy and publications analysing SITAR. It sets the background for work that needs to be done in future clinical trials. It also reviews the potential toxicities of immunotherapy and discusses areas where caution is required when combining treatments.