Author: Lori Buchholtz, Alison Garda, Chris L. Hallemeier, Kathryn L. Kolsky, Han Liu, Joseph John Lucido, Marisa Schinter, Andrew J. Veres, Sara Walerak 👨🔬
Affiliation: Mayo Clinic 🌍
Purpose: The C_START initiative aims to streamline and simplify the Direct-to-Unit (DtU) clinical setup and treatment planning process for photon radiation therapy, particularly for emergent cases such as spinal cord compression, or for time-sensitive post-operative heterotopic ossification prophylaxis. The goal was to eliminate the complexities associated with the unplanned treatment mode (UTM) used for drawing treatment fields, reduce manual entry, and enhance patient safety while providing more efficient workflows for healthcare providers.
Methods: The C_START process incorporates automated scripts within the Eclipse treatment planning system, utilizing the linear accelerator’s on-board cone-beam computed tomography (CBCT) for treatment simulation. The workflow is as follows: 1) radiation therapists (RTT) set up patient in comfortable position in treatment room then acquire the CBCT, 2) a base plan using automation scripting, 3) physicists and physicians define the anterior field, 4) the automation script mirrors the field and calculates dose, 5) staff performs a final review of the plan, using RadCalc for secondary dose verification, 6) verification images taken and then treatment delivered. The overall process, from imaging to treatment, can take less than 20 minutes.
Results: The new process demonstrated a significant increase in utilization, with 16 DtU treatments conducted during the 3-month pilot phase compared to 10 in the previous 12 months. During 2022~2024, a total of 100 patients were treated. Overall treatment session time was reduced by 53%.
Conclusion: Feedback from physicians, therapists, and dosimetrists has been uniformly positive, particularly regarding the elimination of UTM mode and increased confidence in treatment accuracy. Challenges included limitations of the Eclipse API, difficulties in handling patients with large body habitus on CBCT, and the initial training barrier. Future improvements will include additional beam arrangements, patient-specific customization, and better integration with diagnostic CT. The C_START process has successfully streamlined workflows, improved efficiency, and enhanced patient safety.