Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI 48073-6769, USA.
Int J Radiat Oncol Biol Phys. 2010 Jun 1;77(2):608-16. doi: 10.1016/j.ijrobp.2009.08.032. Epub 2010 Jan 25.
To present treatment planning case studies for several treatment sites for which volumetric modulated arc therapy (VMAT) could have a positive impact; and to share an initial clinical experience with VMAT for stereotactic body radiotherapy (SBRT).
Four case studies are presented to show the potential benefit of VMAT compared with conformal and intensity-modulated radiotherapy (IMRT) techniques in pediatric cancer, bone marrow-sparing whole-abdominopelvic irradiation (WAPI), and SBRT of the lung and spine. Details of clinical implementation of VMAT for SBRT are presented. The VMAT plans are compared with conventional techniques in terms of dosimetric quality and delivery efficiency.
Volumetric modulated arc therapy reduced the treatment time of spine SBRT by 37% and improved isodose conformality. Conformal and VMAT techniques for lung SBRT had similar dosimetric quality, but VMAT had improved target coverage and took 59% less time to deliver, although monitor units were increased by 5%. In a complex pediatric pelvic example, VMAT reduced treatment time by 78% and monitor units by 25% compared with IMRT. A double-isocenter VMAT technique for WAPI can spare bone marrow while maintaining good delivery efficiency.
Volumetric modulated arc therapy is a new technology that may benefit different patient populations, including pediatric cancer patients and those undergoing concurrent chemotherapy and WAPI. Volumetric modulated arc therapy has been used and shown to be beneficial for significantly improving delivery efficiency of lung and spine SBRT.
展示几个治疗部位的治疗计划案例研究，这些部位使用容积旋转调强放疗（VMAT）可能会产生积极影响；并分享立体定向体部放疗（SBRT）中 VMAT 的初步临床经验。
呈现四个案例研究，展示与常规技术相比，VMAT 在儿科癌症、骨髓保护全腹骨盆照射（WAPI）和肺与脊柱 SBRT 中的潜在优势。介绍了 SBRT 中 VMAT 的临床实施细节。从剂量学质量和治疗效率方面比较了 VMAT 计划与常规技术。
脊柱 SBRT 的 VMAT 治疗时间缩短了 37%，等剂量线适形度提高。肺 SBRT 的常规技术和 VMAT 技术具有相似的剂量学质量，但 VMAT 提高了靶区覆盖率，治疗时间缩短了 59%，尽管监视器单位增加了 5%。在一个复杂的儿科骨盆病例中，VMAT 与 IMRT 相比，治疗时间缩短了 78%，监视器单位减少了 25%。WAPI 的双等中心 VMAT 技术可以在保持良好治疗效率的同时保护骨髓。
容积旋转调强放疗是一种新技术，可能对不同的患者群体有益，包括儿科癌症患者和接受同步化疗和 WAPI 的患者。VMAT 已被用于并显示出可显著提高肺和脊柱 SBRT 的治疗效率。
