Type Testing Validation of Dose Calculation Accuracy for Intensity-Modulated Proton Therapy (IMPT) for a Newly Developed Treatment Planning System Curaproton
Abstract
Purpose
To validate the accuracy of CuraProton, a newly developed proton therapy treatment planning system, through comprehensive type testing of depth dose distributions and transverse dose profiles across multiple clinically complex scenarios, in strict compliance with the Chinese medical device industry standard YY/T 1905-2023 Requirements for Calculation Accuracy of Planned Dose in Light Ion Beam Radiotherapy.
Methods
Four phantom configurations representing various clinical complexity were evaluated: R14M10FS10 and R33M10FS10 in solid water phantoms (simple cases), R20M10FS10 in a double-wedge phantom (moderate complexity), and R15M10FS10 in an anthropomorphic head phantom (high complexity). Test plans generated by a newly developed CuraProton TPS and were transferred to and delivered on the ProBeam proton therapy system at our center. Dosimetric validation was performed by measuring depth dose distributions with a PPC05 ionization chamber along the beam central axis and acquiring transverse dose profiles using an IBA Matrixx PT 2D detector array at the center plane of the spread-out Bragg peak.
Results
CuraProton TPS demonstrated high dosimetric accuracy across all test cases, meeting YY/T 1905-2023 requirements. For depth dose distributions, absolute dose deviations were within ±1.8% in the entrance region, ±2.0% in the high-dose plateau region,±1.2% in the out-of-field region，and ±5.0% in the proximal and distal fall-off regions. For transverse dose profiles, deviations were within ±1.8% in the high-dose plateau, ±1.2% in the out-of-field region，and ±8.7% in the penumbra,. All measured dose deviations in the proximal and distal fall-off regions and penumbra regions fully complied with the scenario-adaptive tolerance criteria stipulated in YY/T 1905-2023：deviations within ±10% for simple scenarios and ±15% for moderate/complex scenarios.
Conclusion
The rigorously validated results demonstrated that the new TPS CuraProton is in full compliance with YY/T 1905-2023 standards with adequate dose calculation accuracy. It establishes a solid foundation for the subsequent clinical trials of the CuraProton system in China.