Calculating dose‐averaged linear energy transfer in an analytical treatment planning system for carbon‐ion radiotherapy

作者：Weiwei Wang, Ping Li, Kambiz Shahnazi, Xiaodong Wu, Jingfang Zhao · 发表于：Journal of Applied Clinical Medical Physics · 年份：2022 · DOI：10.1002/acm2.13866 · 被引用次数：10 · 研究领域：Radiation Therapy and Dosimetry、Advanced Radiotherapy Techniques、Effects of Radiation Exposure

BACKGROUND: Compelling evidence shows the association between the relative biological effectiveness (RBE) of carbon-ion radiotherapy (CIRT) and the dose averaged linear energy transfer (LETd). However, the ability to calculate the LETd in commercially available treatment planning systems (TPS) is lacking. PURPOSE: This study aims to develop a method of calculating the LETd of CIRT plans that could be robustly carried out in RayStation (V10B, Raysearch, Sweden). METHODS: The calculation used the fragment spectra in RayStation for the CIRT treatment planning. The dose-weighted averaging procedure was supported by the microdosimetric kinetic model (MKM). The MKM-based pencil beam dose engine (PBA, v4.2) for calculating RBE-weighted doses was reformulated to become a LET-weighted calculating engine. A separate module was then configured to inversely calculate the LETd from the absorbed dose of a plan and the associated fragment spectra. In this study, the ion and energy-specific LET table in the LETd module was further matched with the values decoded from the baseline data of the Syngo TPS (V13C, Siemens, Germany). The LETd distributions of several monoenergetic and modulated beams were calculated and validated against the values derived from the Syngo TPS and the published data. RESULTS: The differences in LETds of the monoenergetic beams between the new method and the traditional method were within 3% in the entrance and Bragg-peak regions. However, a larger difference was obse...