Comparison of doses of heart and substructures in VMAT versus IMRT for middle thoracic esophageal cancer(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2018年第6期
- Page:
- 648-653
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Comparison of doses of heart and substructures in VMAT versus IMRT for middle thoracic esophageal cancer
- Author(s):
- AN Yijun1; ZHAO Biao1; YU Lidan2; HE Liqiu1; ZHAO Yutao1; YANG Yi1
- 1. Department of Radiation Oncology, the Third Affiliated Hospital of Kunming Medical University & Yunnan Cancer Hospital, Kunming 650118, China; 2. Graduate School, Kunming Medical University, Kunming 650500, China
- Keywords:
- ; Keywords: esophageal cancer; volumetric modulated arc therapy; intensity-modulated radiotherapy; heart; dosimetry
- PACS:
- R735.1
- DOI:
- DOI:10.3969/j.issn.1005-202X.2018.06.006
- Abstract:
- Abstract: Objective To compare the differences in the doses of heart and substructures in volumetric modulated arc therapy (VMRT) and intensity-modulated radiotherapy (IMRT) of middle thoracic esophageal cancer, and investigate a better radiotherapy technology for heart protection. Methods Fifteen patients with middle thoracic esophageal cancer confirmed by pathology were enrolled in this study. The target areas and organs-at-risk were delineated with the same criterion, and meanwhile 7-fields IMRT and 1-arc VMAT plan were designed for each patient. The dose of heart and substructures were compared between the two plans. Results Under the same target coverage, compared with IMRT plan, VMAT plan had significant reductions in the high-dose regions of heart and substructures, particularly in V20-V40 of the whole heart, V20 and V25 of pericardium, V40 of left atrium, V25 and V30 of right atrium, V20-V30 of right ventricle, V20-V30 of planning risk volume-right coronary artery (PRV-RCA) (all P<0.05). Moreover, the mean dose of the whole heart, left ventricle, right ventricle and PRV-RCA in VMAT plan were much lower than those in IMRT plan (P<0.05). The comparison in low-dose regions revealed that the V5 of right ventricle was higher and the V5 and V10 of PRV-LAD were lower in VMAT plan as compared with IMRT plan (P<0.05). No statistical differences were found in other parameters (P>0.05). Conclusion Both VMAT and IMRT can meet the radiotherapy needs of middle thoracic esophageal cancer patients, but VMAT can further decrease the doses of heart and substructures and reduce the heart injuries caused by radiotherapy.
Last Update: 2018-06-22