Sub-analysis of multi-center planning radiosurgery for intracranial metastases through automation (MC-PRIMA) comparing plan quality between UK and International Centers

Abstract Objectives A sub-analysis of the MC-PRIMA study was performed to compare the plan quality of stereotactic radiosurgery (SRS) to brain metastases between UK and other international centers. Methods and materials: Six SRS centers from the UK and nineteen from other international centers autoplanned using the Multiple Brain Mets software for a five brain metastases study case from the planning competition that was originally organized by the Trans-Tasmania Radiation Oncology Group (TROG). 23 dosimetric metrics and the resulting composite plan score (maximum 150) per the TROG planning competition were compared between the UK and the other international centers. Planning experience and planning time from each planner were recorded and compared. Results Planning experiences between two groups are equal. Except for mean dose to the hippocampus, all other 22 dosimetric metrics were comparable between the UK and the other international centers. The inter-planner variations in these 23 dosimetric metrics and the composite plan score were also statistically equivalent. Planning time is slightly longer in the UK group (mean = 86.8 minutes ) with a mean difference of 50.3 minutes. Conclusions Autoplanning effectively achieves standardization of the plan quality of SRS to multiple brain metastases within UK and further against other international centers. Significant planning efficiency gain may help to increase the capacity of SRS service by alleviating the clinical and technical loadings.