3106 - Clinical Integration of an Ultra-Compact Fixed-Beam Upright Proton Therapy System: Initial Experience

12:30pm - 01:45pm ET

Poster Hall - Exhibit Hall A

Screen: 8

POSTER

Presenter(s)

Yuan Rao, MD - Stanford Cancer Institute Palo Alto, Palo Alto, CA

Y. J. Rao¹, S. M. Hiniker¹, S. Charyyev¹, V. Nazaryan², L. Ooyama³, V. Maradia¹, Z. Jiang², V. J. Heng¹, C. F. Chuang¹, L. E. K. Ghomsi⁴, L. Skinner⁵, B. Han⁶, N. Kovalchuk⁶, L. Xing⁶, M. Surucu⁶, Y. Yang⁶, and B. W. Loo Jr¹; ¹Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, ²Stanford University, Palo Alto, CA, ³Mevion Medical Systems, Littleton, MA, United States, ⁴Department of Radiation Oncology, Stanford University, Palo Alto, CA, ⁵Stanford University, Stanford, CA, ⁶Department of Radiation Oncology, Stanford University, Stanford, CA

Purpose/Objective(s):

Ultra-compact fixed-beam proton therapy (PT) with upright positioning has unique considerations for integration into an existing radiation oncology department. This study describes the initial integration and activation experience at a single institution.

Materials/Methods:

A multidisciplinary implementation group designed a staged go-live process for first clinical use, which occurred in parallel with physical construction and commissioning. Departmental integration included construction/physical considerations, defining staffing, training requirements, and early patient selection criteria. Proton-specific and upright-specific considerations were incorporated into simulation, treatment planning, clinical review and quality assurance (QA) processes.

Results:

The proton system was built into a modified space that previously held a clinical photon linac. The proton vault abuts vaults containing a low-field MRI linac and robotic radiosurgery linac; both continued service during construction and commissioning. Construction began 9/2024, with the cyclotron delivered 1/2025. Installation was completed by 12/2025, and commissioning is ongoing in 2/2026. Multidisciplinary leadership (radiation oncologists, medical physicists, dosimetrists, therapists, and administrators) organized integration and activation. Key activities included coordination with the proton vendor, identifying disease-site physician champions, commissioning, and regulatory approval. Additional activities included identifying staffing and training needs among all professionals (physicians, physicists, therapists, dosimetrists, billing, nursing, scheduling, etc). End-to-end workflows supporting upright PT were implemented within routine departmental operations. Treatment planning, documentation, and delivery processes were integrated with established clinical review and QA pathways. Upright simulation and treatment processes were feasible within standard scheduling and staffing structures. Key implementation challenges and workflow adaptations were identified, including staff training cadence, treatment planning, and simulation-to-treatment alignment. A proton triage meeting identified patients that may benefit from upright PT including those with pediatric, young-adult, CNS, H&N, thoracic malignancies; and patients unable to tolerate a supine position. Early experience supports the practicality and advantages of integrating upright PT delivery within existing radiation oncology infrastructure.

Conclusion:

Fixed-beam upright PT can be feasibly integrated into an existing radiation oncology center. Upright positioning introduces novel requirements for simulation, immobilization, planning, and imaging. This initial experience may guide other centers pursuing upright PT.