Clinical experience on patient‐specific quality assurance for CBCT‐based online adaptive treatment plan

作者：Chenyang Shen, Liyuan Chen, Xinran Zhong, Yesenia Gonzalez, Justin Visak, Boyu Meng, Enobong Inam, David Parsons, Andrew Godley, Steve Jiang, Bin Cai, Mu‐Han Lin · 发表于：Journal of Applied Clinical Medical Physics · 年份：2023 · DOI：10.1002/acm2.13918 · 被引用次数：18 · 研究领域：Advanced Radiotherapy Techniques、Advances in Oncology and Radiotherapy、Radiation Therapy and Dosimetry

PURPOSE: Ethos CBCT-based adaptive radiotherapy (ART) system can generate an online adaptive plan by re-optimizing the initial reference plan based on the patient anatomy at the treatment. The optimization process is fully automated without any room for human intervention. Due to the change in anatomy, the ART plan can be significantly different from the initial plan in terms of plan parameters such as the aperture shapes and number of monitor units (MUs). In this study, we investigated the feasibility of using calculation-based patient specific QA for ART plans in conjunction with measurement-based and calculation-based QA for initial plans to establish an action level for the online ART patient-specific QA. METHODS: A cohort of 98 cases treated on CBCT-based ART system were collected for this study. We performed measurement-based QA using ArcCheck and calculation-based QA using Mobius for both the initial plan and the ART plan for analysis. For online the ART plan, Mobius calculation was conducted prior to the delivery, while ArcCheck measurement was delivered on the same day after the treatment. We first investigated the modulation factors (MFs) and MU numbers of the initial plans and ART plans, respectively. The γ passing rates of initial and ART plan QA were analyzed. Then action limits were derived for QA calculation and measurement for both initial and online ART plans, respectively, from 30 randomly selected patient cases, and were evaluated using the other 68 patient...