Dosimetric impacts of dose grid resolution on stereotactic body radiotherapy for non-small-cell lung cancer(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2019年第1期
- Page:
- 6-11
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Dosimetric impacts of dose grid resolution on stereotactic body radiotherapy for non-small-cell lung cancer
- Author(s):
- CHEN Xiang1; SHAN Guoping2; SHAO Kainan2; LI Yucheng1; YANG Yiwei2; LI Pu2; WANG Binbing2; ZHOU Jianliang1
- 1. School of Nuclear Science and Technology, University of South China, Hengyang 421001, China; 2. Department of Radiotherapy Physics, Zhejiang Cancer Hospital, Hangzhou 310022, China
- Keywords:
- ; Keywords: non-small-cell lung cancer; stereotactic body radiotherapy; dose grid; resolution
- PACS:
- R730.55；R811.1
- DOI:
- DOI:10.3969/j.issn.1005-202X.2019.01.002
- Abstract:
- Abstract: Objective To quantitatively analyze the effects of dose grid resolution on the dose distribution of stereotactic body radiotherapy (SBRT) of non-small-cell lung cancer (NSCLC) for providing guidance in selecting the optimal dose grid resolution for the design of SBRT plan of lung cancer. Methods Ten patients with NSCLC were enrolled in this study. With 0.20 cm dose grid resolution, volumetric modulated arc therapy technology was used to design SBRT plan, and then the dose grid resolution was set to 0.40, 0.30, 0.25, 0.15, 0.10 cm to calculate the final dose. Several dosimetric parameters of planning target volume and organs-at-risk, namely the D2%, Dmean, D98%, homogeneity index, conformity index of planning target areas, and the relevant dosimetric parameters of the whole lung, chest wall, esophagus, heart, spinal cord, aorta, tracheal tree, were compared among 6 SBRT plans with different dose grid resolutions. Results The D2%, Dmean and conformity index in plans with dose grid resolutions of 0.40, 0.30, 0.25, 0.15 and 0.10 cm were statistically different from those in the plans with dose grid resolution of 0.20 cm (P<0.05). Statistical differences were also found in homogeneity index between the plans with dose grid resolution of 0.20 cm and the other plans (P<0.05), except for the plans with dose grid resolution of 0.15 cm. The relevant dosimetric parameters of the whole lung, chest wall, esophagus, heart, spinal cord, aorta and tracheal tree in plans with dose grid resolution larger than 0.2 cm (0.40, 0.30, 0.25 cm) were statistically different from those in plans with dose grid resolution of 0.2 cm (P <0.05). For plans with dose grid resolution less than 0.2 cm (0.15, 0.10 cm) and plans with dose grid resolution of 0.2 cm, significant differences were found in the [V10],[V20],[V12.5]and [V13.5]of the whole lung (P<0.05), not in the relevant dosimetry parameters of chest wall, esophagus, heart, spinal cord, aorta and tracheal tree (P>0.05). Conclusion Dose grid resolution can affect the accuracy of dose calculation. In the design of SBRT plans for NSCLC, dose grid resolution of 0.2 cm or smaller is recommended.
Last Update: 2019-01-24