Dosimetric study of TomoDirect technology in radiotherapy for nasopharyngeal carcinoma(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2018年第2期
- Page:
- 166-170
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Dosimetric study of TomoDirect technology in radiotherapy for nasopharyngeal carcinoma
- Author(s):
- ZHAO Hongli; LIU Hui; ZHONG Yahua; XIE Conghua; WANG Xiaoyong
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan 430071, China
- Keywords:
- ; nasopharyngeal carcinoma; TomoDirect technology; fixed-field intensity-modulated radiotherapy; TomoHelical technology; dosimetry
- PACS:
- R815
- DOI:
- DOI:10.3969/j.issn.1005-202X.2018.02.009
- Abstract:
- Objective To evaluate the dosimetric differences of TomoDirect (TD), TomoHelical (TH) and fixed-field intensity-modulated radiotherapy (FF-IMRT) plans for nasopharyngeal carcinoma (NPC). Methods Ten patients with NPC were enrolled in this study, and based on their CT images, three plans were designed for each patient, namely TH, TD and FF-IMRT plans. The dose distribution in target areas, organs-at-risk and normal tissues were evaluated. Furthermore, the dosimetric differences were compared among three plans by single factor analysis of variance, and compared in pairs by LSD method. Results For dosimetric parameters in target areas, TD plans didn’t showed any statistical differences with TH and FF-IMRT plans. TD and TH plans showed significant improvement over IMRT plans in terms of OAR protection. Compared with FF-IMRT plan, the maximum dose of spinal cord in the other two plans was reduced by about 4 Gy (P=0.000); the mean dose of parotid gland was decreased by about 20% (P=0.000) and the D33, D50 and D60 were significantly lower (P=0.000); the mean dose of oral cavity and larynx were reduced by about 7 Gy and 20 Gy, respectively (P=0.000, 0.000); and the maximum dose of temporomandibular joint was lower by 10 Gy (P=0.000). However, FF-IMRT plan was superior to TD and TH plans in the protection of optic nerve and chiasm. Besides, TD plans showed certain advantages in the irradiation dose of the normal tissues outside the target areas. Conclusion For patients with NPC, the differences in dosimetric parameters between TD and TH plans were trivial, and both TD and TH plans showed significant improvements over IMRT plans, completely meeting the clinical requirements. TD technology is feasible to treat patients with NPC.
Last Update: 2018-01-29