Evidence-based Peer Review for Radiation Therapy - Updated Review of the Literature with a Focus on Tumour Subsite and Treatment Modality.

Technological advances in radiation therapy permit steep dose gradients from the target to spare normal tissue, but increase the risk of geographic miss. Suboptimal target delineation adversely affects clinical outcomes. Prospective peer review is a method for quality assurance of oncologists' radiotherapy plans. Published surveys suggest it is widely implemented. However, it may not be feasible to review every case before commencement of radiation therapy in all departments. The rate of plan changes following peer review of cases without a specific subsite or modality is typically around 10%. Stereotactic body radiation therapy, head and neck, gynaecological, gastrointestinal, haematological and lung cases are associated with higher rates of change of around 25%. These cases could thus be prioritised for peer review. Other factors may limit peer review efficacy including organisational culture, time constraints and the physical environment in which sessions are held. Recommendations for peer review endorsed by the American Society for Radiation Oncology were made available in 2013, but a number of relevant studies have been published since. Here we review and update the literature, and provide an updated suggestion for the implementation of peer review to serve as an adjunct to published guidelines. This may help practitioners evaluate their current processes and maximise the utility and effectiveness of peer review sessions.