Implementing a fully computed tomography-free online adaptive palliative radiotherapy: a one-visit workflow.

Area of Science:

• Radiation Oncology
• Medical Imaging
• Radiotherapy Workflow Optimization

Background:

• Conventional CT-based radiotherapy workflows cause significant delays and resource strain.
• Advances in cone-beam CT (CBCT) offer potential for accurate dose calculation without planning CT.
• High-quality CBCT enables development of CT-free radiotherapy workflows.

Purpose of the Study:

• To evaluate the feasibility and efficiency of a fully CT-free online adaptive workflow for same-day palliative radiotherapy.
• To assess the use of high-quality CBCT in a CT-free planning and delivery process.
• To compare workflow times and plan quality against conventional CT-based methods.

Main Methods:

• Prospective study of 15 patients undergoing single-fraction palliative radiotherapy.
• Utilized a reference plan on a phantom; no planning CT was acquired.
• Employed Varian Ethos 2.0 with HyperSight CBCT for online plan adaptation and delivery on the treatment day.

Main Results:

• All 15 treatments were successfully delivered, meeting clinical objectives.
• The CT-free workflow reduced median departmental time to 73 minutes (vs. 335 minutes for CT-based).
• Urgent cases demonstrated rapid referral-to-treatment times (2.5 hours in one instance).

Conclusions:

• A fully CT-free workflow is feasible and efficient for same-day palliative radiotherapy.
• This approach significantly reduces departmental workload and is suitable for urgent treatments.
• High-quality CBCT facilitates accurate planning and delivery, enabling rapid patient throughput.