Dosimetric comparison of coplanar and non-coplanar volumetric modulated arc therapy for lung cancer(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2018年第11期
- Page:
- 1246-1251
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Dosimetric comparison of coplanar and non-coplanar volumetric modulated arc therapy for lung cancer
- Author(s):
- HU Xiaowei1; SHI Yujing1; LI Jinkai2; CHENG Hongyan2; SUN Xinchen2; GU Xiaohuan2
- 1. Department of Special Medicine, Nanjing Medical University, Nanjing 210009, China; 2. Department of Radiation Oncology, the First Affiliated Hospital of Nanjing Medical University, Nanjing 210009, China
- Keywords:
- Keywords: lung cancer; non-coplanar; volumetric modulated arc therapy; stereotactic body radiotherapy
- PACS:
- R312;R811.1
- DOI:
- DOI:10.3969/j.issn.1005-202X.2018.11.002
- Abstract:
- Abstract: Objective To investigate the dosimetric differences between coplanar and non-coplanar volumetric modulated arc therapy (VMAT) in treatment of central type lung cancer and peripheral lung cancer. Methods A total of 14 patients with single lesion of lung cancer, including 7 cases of central type lung cancer and 7 cases of peripheral lung cancer, were selected. Two plans, namely coplanar and non-coplanar VMAT plans, were designed for each patient. The conformity index, homogeneity index and gradient index of target areas were compared, and several indexes of organs-at-risk, including the V1, V2.5, V5, V20, Dmean of lungs, the V1, V5 of contralateral lung, the Dmean of heart, the Dmean of esophagus, the Dmax of spinal cord, and the Dmax, V30 of chest wall, were also compared. Results The gradient index of target areas, the V30 of chest wall, and the V20 of lungs in non-coplanar VMAT plan were superior to those in coplanar VMAT plan, and the differences were more obvious in patients with central type lung cancer, with statistical significances (P<0.05). The V1 of bilateral lungs and contralateral lung was higher in non-coplanar VMAT plan than in coplanar VMAT plan (P<0.05), and the Dmean of heart in non-coplanar VMAT plans was higher than that in coplanar VMAT plans, without any statistical differences (P>0.05). Moreover, the number of monitor units in non-coplanar VMAT plan was higher than that in coplanar VMAT plan (P<0.05). Conclusion Non-coplanar VMAT plan has a steeper dose gradient than coplanar VAMT plan, which is more advantageous for the protection of the chest wall and lung, especially for patients with central type lung cancer, providing a new idea for designing treatment plans of lung cancer.
Last Update: 2018-11-22