Wada Yutaro, Monzen Hajime, Tamura Mikoto, Otsuka Masakazu, Inada Masahiro, Ishikawa Kazuki, Doi Hiroshi, Nakamatsu Kiyoshi, Nishimura Yasumasa
Department of Radiation Oncology, Faculty of Medicine, Kindai University, Osaka, Japan.
Department of Medical Physics, Graduate School of Medical Sciences, Kindai University, Osakasayama, Osaka, Japan.
J Med Phys. 2021 Jan-Mar;46(1):7-15. doi: 10.4103/jmp.JMP_67_20. Epub 2021 May 5.
We investigated the performance of the simplified knowledge-based plans (KBPs) in stereotactic body radiotherapy (SBRT) with volumetric-modulated arc therapy (VMAT) for lung cancer.
For 50 cases who underwent SBRT, only three structures were registered into knowledge-based model: total lung, spinal cord, and planning target volume. We performed single auto-optimization on VMAT plans in two steps: 19 cases used for the model training (closed-loop validation) and 16 new cases outside of training set (open-loop validation) for TrueBeam (TB) and Halcyon (Hal) linacs. The dosimetric parameters were compared between clinical plans (CLPs) and KBPs: CLP, KBP-TB and KBP-Hal in closed-loop validation, CLP, KBP-TB and KBP-Hal in open-loop validation.
All organs at risk were comparable between CLPs and KBPs except for contralateral lung: V of KBPs was approximately 3%-7% higher than that of CLPs. V of total lung for KBPs showed comparable to CLPs; CLP vs. KBP-TB and CLP vs. KBP-Hal: 4.36% ± 2.87% vs. 3.54% ± 1.95% and 4.36 ± 2.87% vs. 3.54% ± 1.94% ( = 0.54 and 0.54); CLP vs. KBP-TB and CLP vs. KBP-Hal: 4.18% ± 1.57% vs. 3.55% ± 1.27% and 4.18% ± 1.57% vs. 3.67% ± 1.26% ( = 0.19 and 0.27). CI of KBPs with both linacs was superior to that of the CLP in closed-loop validation: CLP vs. KBP-TB vs. KBP-Hal: 1.32% ± 0.12% vs. 1.18% ± 0.09% vs. 1.17% ± 0.06% ( < 0.01); and open-loop validation: CLP vs. KBP-TB vs. KBP-Hal: 1.22% ± 0.09% vs. 1.14% ± 0.04% vs. 1.16% ± 0.05% ( ≤ 0.01).
The simplified KBPs with limited number of structures and without planner intervention were clinically acceptable in the dosimetric parameters for lung VMAT-SBRT planning.
我们研究了基于知识的简化计划（KBP）在肺癌立体定向体部放疗（SBRT）中采用容积调强弧形放疗（VMAT）的性能。
对于50例行SBRT的患者，仅将三个结构注册到基于知识的模型中：全肺、脊髓和计划靶体积。我们分两步对VMAT计划进行单次自动优化：19例用于模型训练（闭环验证），16例训练集外的新病例（开环验证）用于TrueBeam（TB）和Halcyon（Hal）直线加速器。比较了临床计划（CLP）和KBP之间的剂量学参数：闭环验证中的CLP、KBP-TB和KBP-Hal，开环验证中的CLP、KBP-TB和KBP-Hal。
除对侧肺外，所有危及器官在CLP和KBP之间具有可比性：KBP的V值比CLP高约3%-7%。KBP的全肺V值与CLP相当；CLP与KBP-TB以及CLP与KBP-Hal比较：4.36%±2.87%对3.54%±1.95%以及4.36±2.87%对3.54%±1.94%（P=0.54和0.54）；CLP与KBP-TB以及CLP与KBP-Hal比较：4.18%±1.57%对3.55%±1.27%以及4.18%±1.57%对3.67%±1.26%（P=0.19和0.27）。两种直线加速器的KBP的CI在闭环验证中均优于CLP：CLP与KBP-TB与KBP-Hal比较：1.32%±0.12%对1.18%±0.09%对1.17%±0.06%（P<0.01）；开环验证：CLP与KBP-TB与KBP-Hal比较：1.22%±0.09%对1.14%±0.04%对1.16%±0.05%（P≤0.01）。
结构数量有限且无需计划者干预的简化KBP在肺VMAT-SBRT计划的剂量学参数方面在临床上是可接受的。
