National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital and Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
Sci Rep. 2021 Feb 18;11(1):4065. doi: 10.1038/s41598-021-83648-5.
To perform a comparison of the different stereotactic body radiotherapy (SBRT) plans between the Varian EDGE and CyberKnife (CK) systems for locally advanced unresectable pancreatic cancer. Fifteen patients with pancreatic cancer were selected in this study. The median planning target volume (PTV) was 28.688 cm (5.736-49.246 cm). The SBRT plans for the EDGE and CK were generated in the Eclipse and Multiplan systems respectively with the same contouring and dose constrains for PTV and organs at risk (OARs). Dose distributions in PTV were evaluated in terms of coverage, conformity index (CI), new conformity index (nCI), homogeneity index (HI), and gradient index (GI). OARs, including spinal cord, bowel, stomach, duodenum and kidneys were statistically evaluated by different dose-volume metrics and equivalent uniform dose (EUD). The volume covered by the different isodose lines (ISDL) ranging from 10 to 100% for normal tissue were also analyzed. All SBRT plans for EDGE and CK met the dose constraints for PTV and OARs. For the PTV, the dosimetric metrics in EDGE plans were lower than that in CK, except that D and GI were slightly higher. The EDGE plans with lower CI, nCI and HI were superior to generate more conformal and homogeneous dose distribution for PTV. For the normal tissue, the CK plans were better at OARs sparing. The radiobiological indices EUD of spinal cord, duodenum, stomach, and kidneys were lower for CK plans, except that liver were higher. The volumes of normal tissue covered by medium ISDLs (with range of 20-70%) were lower for CK plans while that covered by high and low ISDLs were lower for EDGE plans. This study indicated that both EDGE and CK generated equivalent plan quality, and both systems can be considered as beneficial techniques for SBRT of pancreatic cancer. EDGE plans offered more conformal and homogeneous dose distribution for PTV, while the CK plans could minimize the exposure of OARs.
为了比较瓦里安 EDGE 和 CyberKnife（CK）系统在局部晚期不可切除胰腺癌中的不同立体定向体放射治疗（SBRT）计划。本研究选择了 15 例胰腺癌患者。中位计划靶区（PTV）为 28.688cm（5.736-49.246cm）。EDGE 和 CK 的 SBRT 计划分别在 Eclipse 和 Multiplan 系统中生成，PTV 和危及器官（OAR）的轮廓和剂量限制相同。通过覆盖度、适形指数（CI）、新适形指数（nCI）、均匀性指数（HI）和梯度指数（GI）评估 PTV 中的剂量分布。通过不同的剂量-体积指标和等效均匀剂量（EUD）对脊髓、肠道、胃、十二指肠和肾脏等 OAR 进行统计学评估。还分析了正常组织不同等剂量线（ISDL）覆盖的体积，范围从 10%到 100%。EDGE 和 CK 的所有 SBRT 计划均符合 PTV 和 OAR 的剂量限制。对于 PTV，EDGE 计划的剂量学指标低于 CK，除了 D 和 GI 略高。EDGE 计划的 CI、nCI 和 HI 较低，能够更好地生成更适形和均匀的剂量分布。对于正常组织，CK 计划在保护 OAR 方面更好。除了肝脏较高外，CK 计划的脊髓、十二指肠、胃和肾脏的放射生物学指数 EUD 较低。CK 计划的中 ISDL （20-70%）覆盖的正常组织体积较低，而 EDGE 计划的高 ISDL 和低 ISDL 覆盖的正常组织体积较低。这项研究表明，EDGE 和 CK 都能产生等效的计划质量，这两种系统都可以被认为是胰腺癌 SBRT 的有益技术。EDGE 计划为 PTV 提供了更适形和均匀的剂量分布，而 CK 计划可以最大限度地减少 OAR 的暴露。
