Different intensity-modulated radiotherapy plans for nasopharyngeal carcinoma: a dosimetric comparison among JTT-FFF, JTT-FF, SJT-FFF and SJT-FF(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2020年第7期
- Page:
- 858-862
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Different intensity-modulated radiotherapy plans for nasopharyngeal carcinoma: a dosimetric comparison among JTT-FFF, JTT-FF, SJT-FFF and SJT-FF
- Author(s):
- HUANG Xia1; SU Kunpu2; LUO Huanli1; JIN Fu1; WANG Ying1
- 1. Chongqing University Cancer Hospital/Chongqing Cancer Institute/Chongqing Cancer Hospital, Chongqing 400030, China 2. Army Medical Center, Chongqing 400010, China
- Keywords:
- Keywords: nasopharyngeal carcinoma jaw tracking technique flattening filter free intensity-modulated radiotherapy dosimetry
- PACS:
- R739.62；R815.2
- DOI:
- DOI:10.3969/j.issn.1005-202X.2020.07.011
- Abstract:
- Abstract: Objective To analyze the dose comparison of intensity-modulated radiotherapy (IMRT) plans for nasopharyngeal carcinoma (NPC) using 4 different modes for providing guidance and reference for the selection of the optimal treatment technique. Methods Ten patients with early NPC were enrolled in the study. Treatment planning system (Varian Eclipse, Version 13.6) was used to design 4 different IMRT plans for each patient using jaw tracking technique with flattening filter free mode (JTT-FFF), jaw tracking technique with flattening filter mode (JTT-FF), static jaw technique with flattening filter free mode (SJT-FFF) and static jaw technique with flattening filter mode (SJT-FF), separately. Monitor units and the dosimetric parameters of target areas, organs-at-risk and normal tissues were analyzed. Results The target coverage of the 4 groups of plans met clinical requirements, and there was no statistical difference in conformity index (P>0.05). The homogeneity index of the target areas in SJT-FF plan was the lowest, and was statistically different from that of JTT plans (P<0.05), but there was no statistical difference compared with SJT-FFF plan (P>0.05). The maximum dose of lens, the mean dose of eyeball, oral cavity, temporal lobe, mandible and Body in JTT-FFF plan were the lowest, but machine units was the highest. The maximum dose of brainstem, hypophysis, chiasma, optic nerve, spinal cord, and the mean dose of parotid, larynx, and inner ear in JTT-FF plan were the lowest. Conclusion All the 4 plans can meet clinical requirements, and the conformity index of the target areas is similar in 4 plans. The target homogeneity of JTT plans is inferior to that of SJT plan, but JTT plan can better reduce the dose to organs-at-risk and normal tissues.
Last Update: 2020-07-28