PDF(Pubmed)
Abstract：
The present study aimed to evaluate whether an adapted plan with Ethos™ could be used for pharyngeal cancer. Ten patients with pharyngeal cancer who underwent chemoradiotherapy with available daily cone-beam computed tomography (CBCT) data were included. Simulated treatments were generated on the Ethos™ treatment emulator using CBCTs every four to five fractions for two plans: adapted and scheduled. The simulated treatments were divided into three groups: early (first-second week), middle (third-fourth week), and late (fifth-seventh week) periods. Dose-volume histogram parameters were compared for each period between the adapted and scheduled plans in terms of the planning target volume (PTV) (D98%, D95%, D50% and D2%), spinal cord (Dmax and D1cc), brainstem (Dmax) and ipsilateral and contralateral parotid glands (Dmedian and Dmean). The PTV D98%, D95% and D2% of the adapted plan were significantly higher than those of the scheduled plans in all periods, except for D98% in the late period. The adapted plan significantly reduced the spinal cord Dmax and D1cc compared with the scheduled plan in all periods. Ipsilateral and contralateral parotid glands Dmean of the adapted plan were lower than those of scheduled plan in the late period. In conclusion, the present study revealed that the adapted plans could maintain PTV coverage while reducing the doses to organs at risk in each period compared with scheduled plans.
摘要：
本研究旨在评估Ethos™的适应性计划是否可用于咽癌。包括10例接受放化疗并获得每日锥形束计算机断层扫描（CBCT）数据的咽癌患者。在Ethos™治疗仿真器上使用CBCT每四至五个部分产生模拟治疗,用于两个计划:适应和计划。模拟治疗分为三组：早期（第一周至第二周），中间（第三至四周），和后期（第五至第七周）。在计划目标体积（PTV）（D98％，D95%,D50%和D2%)，脊髓（Dmax和D1cc），脑干（Dmax）和同侧和对侧腮腺（Dmean和Dmean）。PTVD98%,适应计划的D95%和D2%在所有时期均显著高于预定计划的D95%和D2%,除了后期的D98%。与计划计划相比，适应计划在所有时期均显着降低了脊髓Dmax和D1cc。晚期适应计划的同侧和对侧腮腺Dmean低于计划计划的Dmean。总之,本研究显示,与计划计划相比,调整后的计划可以维持PTV覆盖率,同时减少每个时期对有风险器官的剂量.
