Stereotactic ablative radiotherapy in the UK: current status and developments.

Stereotactic ablative radiotherapy (SABR) has developed from the principles and techniques used in the stereotactic radiosurgery treatment of brain metastases. Advances in computer technology, imaging, planning and treatment delivery and evidence from retrospective analysis of single- and multi-institutional early-phase studies have established SABR in the treatment of medically inoperable early lung cancer. Effective multidisciplinary team working is crucial to safe delivery of SABR. The variation in patient selection, radiotherapy planning and delivery techniques has led to a collective approach to SABR implementation across the UK. Centres developing the technique are represented in the UK SABR Consortium, which is supported by the relevant UK professional bodies and represents a platform to develop extracranial SABR across the UK. The uptake of SABR in the UK has been slowed by workforce issues, but at least 15 centres are currently delivering treatment with over 500 patients treated using UK SABR Consortium guidance. A mentoring program is being piloted helping new centres to develop their programs, and over 30 UK centres are expected to be offering SABR treatment by the end of 2014. The use of consistent guidance for patient selection, treatment planning and delivery in the UK gives the opportunity to collect and audit toxicity and outcome across the centres, contributing to the internationally reported SABR experience. Having established this service in the UK, the development of SABR through clinical research is a priority, and with input from the Radiotherapy Trials Quality Assurance Group, the UK is developing a national study program that includes participation in international trials.