Hiroshima High-Precision Radiotherapy Cancer Center, 3-2-2, Futabanosato, Higashi-ku Hiroshima 732-0057, Japan; Department of Radiation Oncology, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
Hiroshima High-Precision Radiotherapy Cancer Center, 3-2-2, Futabanosato, Higashi-ku Hiroshima 732-0057, Japan; Department of Radiation Oncology, Graduate School of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
Med Dosim. 2022;47(1):48-53. doi: 10.1016/j.meddos.2021.08.001. Epub 2021 Sep 16.
The aim of this study was to compare the quality of dynamic wave arc (DWA) and coplanar volumetric modulated arc therapy (co-VMAT) plans for the treatment of localized prostate cancer. The planning target volume (PTV)-rectum, a section of the PTV comprising the PTV minus that of the rectum, received 78 Gy in 39 fractions as the mean dose to the PTV-rectum. The DWA and co-VMAT plans were generated for each patient using the RayStation treatment planning system for the Vero4DRT system. The PTV-rectum dose (D: the percent dose irradiating 95% of the volume), homogeneity index (HI), conformity index (CI), as well as doses to the bladder wall, rectum wall (V Gy: the percent volume receiving 10-70 Gy), and bilateral femoral heads of the DWA and co-VMAT plans were compared. The output monitor unit (MU) and delivery time obtained for each set of plans were also investigated. In terms of target coverage, the DWA plans provided an average D of 75.5 Gy, which was comparable to the co-VMAT-plan D of 75.2 Gy (p < 0.05). The HI was significantly better with the DWA. As for the DWA plans, the bladder-wall volume receiving 10, 20, 30, and 40 Gy (V) was significantly smaller than that of the co-VMAT plans, and the volume of the rectal wall receiving 10 Gy (V) was significantly larger than that of the co-VMAT plans. The DWA plans yielded a reduced dose to the bilateral femoral heads compared with the co-VMAT plans (p < 0.05). The values of the CI and MU, and the delivery time exhibited no significant differences between the DWA and co-VMAT plans. The DWA plan is a feasible treatment option for prostate cancer radiotherapy.
本研究旨在比较动态波弧（DWA）和共面容积调制弧治疗（co-VMAT）计划治疗局限性前列腺癌的质量。计划靶区（PTV）-直肠，是 PTV 的一部分，包含 PTV 减去直肠的部分，接受 78 Gy 的 39 次分割，作为 PTV-直肠的平均剂量。使用 RayStation 治疗计划系统为 Vero4DRT 系统生成每个患者的 DWA 和 co-VMAT 计划。比较了 PTV-直肠剂量（D：照射 95%体积的百分剂量）、均匀性指数（HI）、适形性指数（CI），以及膀胱壁、直肠壁（V Gy：接受 10-70 Gy 的体积百分比），以及 DWA 和 co-VMAT 计划的双侧股骨头剂量。还研究了每组计划获得的输出监视器单位（MU）和输送时间。在靶区覆盖方面，DWA 计划提供了 75.5 Gy 的平均 D 值，与 co-VMAT 计划的 75.2 Gy 相当（p < 0.05）。HI 明显优于 DWA。对于 DWA 计划，接受 10、20、30 和 40 Gy（V）的膀胱壁体积明显小于 co-VMAT 计划，接受 10 Gy 的直肠壁体积明显大于 co-VMAT 计划。与 co-VMAT 计划相比，DWA 计划使双侧股骨头的剂量降低（p < 0.05）。CI、MU 值和输送时间在 DWA 和 co-VMAT 计划之间没有显著差异。DWA 计划是前列腺癌放射治疗的一种可行的治疗选择。
