Radiotherapy Plan Quality Assurance in the ABC-07 Trial of Stereotactic Body Radiotherapy for Locally Advanced Biliary Tract Cancer

Despite rigorous plan QA, we encountered variability in segmentation and plan coverage. The revision rate was reduced between pre-trial and on-trial cases. Radiotherapy doses in the protocol were achievable in many cases; however, target coverage was frequently compromised to maintain OAR dose constraints. Such compromises should be prespecified in future studies.