Ramping up ART – a Roadmap to Increasing Adaptive RT Capacity
Abstract
Purpose
Requiring a radiation oncologist (RO) to be physically present during online adaptive radiation therapy (ART) constrains scheduling and limits patient access. We have developed and implemented a prescribed workflow to delegate contour review and plan approval to radiation therapists (RTTs) or medical physicists for Ethos cone-beam CT (CBCT)–based online ART for prostate and bladder cancer, including a robust RTT credentialing program.
Methods
Prerequisites for delegation of contour review and clinical plan approval are as follows: (1) Targets must be derivable from an anatomical or easily visualized structure, and (2) there must be three adaptive fractions during which no contour edits are required by the RO, and all clinical goals (targets and organs at risk) are met. Additionally, during sessions in which clinical goals are not met within acceptable variations, or there is contour uncertainty, the RO is called for contour review and plan approval. During RTT credentialling, ROs review Ethos-generated contours that are adjusted by RTTs. RTT contours pass if no RO edits are necessary or if edits would have minimal clinical impact. Credentialing for each disease site required five passing cases, after which RTTs could perform contour adjustment and plan approval without real-time RO review.
Results
From July 2025 to January 2026, five RTTs completed credentialing for prostate and four RTTs completed credentialing for bladder. The option to perform online ART without the RO was launched in September 2025. Following introduction of this delegation pathway, the number of new adaptive patients increased from approximately 1–2 per month to 3–4 per month.
Conclusion
A prescribed workflow and structured RTT credentialing program for contour review and plan approval delegation has improved access to CBCT-based online ART. Our approach has been implemented for prostate and bladder cases, and early metrics indicate that it has improved utilization.