Stereotactic body radiation therapy: transcending the conventional to improve outcomes.

BACKGROUND Intracranial delivery of high-dose radiation treatment with stereotactic techniques has paved the way for treatment of extracranial sites. METHODS The authors review the evolution of stereotactic body radiation therapy (SBRT) and its application to tumors in the lung and abdomen, addressing both the technical concerns associated with treatment delivery and the emerging clinical data. RESULTS Radiation delivery systems have overcome the obstacles with immobilization, respiration, visualization, and daily reproducible imaging. Lung SBRT has been associated with local control rates of over 90%, and liver SBRT has ranged from 55% to 93%. SBRT is being explored in other sites such as the pancreas and kidney. Mature data from ongoing trials will be available in the next 5 years. CONCLUSIONS Modern stereotactic radiation treatment techniques allow the safe delivery of high doses to extracranial sites with minimal toxicity, which results in improved outcomes.