Technique considerations for implementing volumetric-modulated arc therapy for total body irradiation within an Australian tertiary institution.

Over the past decade, our institution delivered conventional total body irradiation (TBI) using Elekta's Monaco treatment planning system (TPS) with an extended SSD field arrangement and 18 megavoltage (MV) energy lateral fields. In 2020, there was a transition to the Eclipse™ treatment planning system and Truebeam® linear accelerators with 6 MV and 10 MV energies. These changes meant that essential components of the existing technique were unavailable for clinical use and a new approach to the institution technique was required to ensure continuation of service. The aim was to implement a volumetric-modulated arc therapy (VMAT) TBI technique using existing infrastructure, the new planning system and treatment hardware to continue providing a TBI service for patients of all ages, including those under general anaesthetic (GA). A multidisciplinary team within the institution was created to evaluate existing literature and to implement a VMAT TBI technique that was feasible within our institution. This article will discuss the resultant technique, the practicalities faced and the radiation therapy pathway within our institution.