Abstract ID: 363 Setup control and intra-fraction motion management in stereotactic body radiotherapy

Abstract

Purpose To review and discuss current approaches and future trends for setup control and intra-fraction motion management in stereotactic body radiation therapy (SBRT). Methods The challenge in SBRT is due to the intrinsic complexities out of intra-fractional target motion with natural physiologic processes. As a result, SBRT requires site-specific approaches in Image Guided Radiation Therapy (IGRT), in order to include intra-fraction motion in the evaluation [1]. This presentation provides an overview of IGRT requirements toward setup control and intra-fraction motion management in SBRT. Results Setup control and intra-fraction management are extremely dependent on the anatomical site, as highlighted by recent studies regarding the efficacy of SBRT. Challenging application examples have been identified, including fiducial-less motion management strategies in lung SBRT [2]. Upcoming integrated approaches relying on MRI-guided SBRT feature the prospect to comprehensively address setup and motion detection in IGRT [3,4]. Conclusions Fiducial-less motion management is a feasible approach and patient-specific margin reduction can reduce safety margins while preserving target coverage. MRI guidance is a future powerful approach for intra-fraction motion management in SBRT: the availability of MR-linacs is expected to provide more extensive data for validation.