Dosimetric study on dynamic IMRT technology based on smart LMC in postoperative radiotherapy for tongue cancer(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2019年第11期
- Page:
- 1255-1260
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Dosimetric study on dynamic IMRT technology based on smart LMC in postoperative radiotherapy for tongue cancer
- Author(s):
- YUE Kun1; 2; YAO Yuan1; JIA Xiaobin1; DONG Xiaoqing3; YUAN Zhengxi1
- 1. Department of Radiotherapy, the Ninth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 201900, China; 2. School of Communication and Information Engineering, Shanghai University, Shanghai 200444, China; 3. Department of Radiotherapy, the Tenth People’s Hospital of Tongji University, Shanghai 200072, China
- Keywords:
- tongue cancer; smart leaf motion calculator; dynamic intensity-modulated radiotherapy; step-and-shoot intensity-modulated radiotherapy; EDGE; postoperative radiotherapy
- PACS:
- R815.6
- DOI:
- DOI:10.3969/j.issn.1005-202X.2019.11.003
- Abstract:
- To investigate dosimetric differences and applicability of different Varian EDGE-based intensity-modulated radiotherapy (IMRT), namely sliding window IMRT (SW), step-and-shoot IMRT (SS) and the novel dynamic IMRT based on smart leaf motion calculator (SW-smart), in the postoperative radiotherapy for tongue cancer. Methods Twenty-six postoperative patients with tongue cancer (stage of T2-3N1-2M0) were enrolled in the study. The plans of SS, SW and SW-smart were designed on Eclipse (version 13.6). The dose distribution of target areas and organs-at-risk among 3 plans were compared and statistically analyzed, and the comparison parameters includes the D98%, D2%, D50%, homogeneity index and conformity index of target areas and the Dmax of spinal cord and brainstem, the Dmean of larynx, parotid-L, parotid-R, pharyngeal constrictors and lip, the V50 of larynx and the V30 of parotid-L and parotid-R. The monitor units and delivery time of 3 plans were also recorded and compared. Results The D50%, conformity index and homogeneity index of planning target volume in SW and SW-smart were superior to those in SS, and the results were statistically significant. SW-smart was slightly better than SW, but there was no statistical significance. SW-smart had the lowest D2% of target areas, followed by SW and SS which had the worst capability to control high dose, and there were significant differences among 3 groups. SW-smart had statistical advantages over SW and SS in normal tissue sparing, and no statistical difference was found in normal tissue sparing between SW and SS. The V50 of larynx and the V30 of parotid-L and parotid-R were similar in 3 plans, without statistical differences. SS had the fewest monitor units and the longest delivery time, and there was no significant difference in monitor units and delivery time between SW-smart and SW. Conclusion Compared with the traditional static and dynamic IMRT, the novel dynamic IMRT technique based on Varian EDGE and smart LMC of new version of Eclipse can provide better target dose distribution and normal tissue sparing, having obvious advantages in postoperative radiotherapy for tongue cancer.
Last Update: 2019-11-28