Non-targeted effects of stereotactic radiotherapy: a review of the evidence coming from the clinical field.

Background: Preclinical animal studies have demonstrated that radiation treatment (RT) can induce effects beyond the anatomical site of irradiation. Non-targeted effects of RT (NTER) have been sporadically reported in clinical settings. However, with the advent of high-dose stereotactic radiation techniques (SRT) and immunotherapy (IT), renewed attention has been given to NTER.