Dosimetric comparison of helical tomotherapy versus fixed-field intensity-modulated radiotherapy for cervical 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:
- 23-28
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Dosimetric comparison of helical tomotherapy versus fixed-field intensity-modulated radiotherapy for cervical cancer
- Author(s):
- LIU Juan1; LI Shuangshuang1; GAO Shanbao1; YAN Jing1; HOU Zhen2; ZHU Lijing1
- 1. Cancer Center, Nanjing Drum Tower Hospital Affiliated to Medical School of Nanjing University, Nanjing 210000, China;
2. Laboratory for Medical Electronics, State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
- Keywords:
- ; Keywords: cervical cancer; radiotherapy; helical tomotherapy; intensity-modulated radiotherapy; dosimetry
- PACS:
- R811.1
- DOI:
- DOI:10.3969/j.issn.1005-202X.2019.01.005
- Abstract:
- Abstract: Objective To compare the dosimetric differences of target areas and organs-at-risk between helical tomotherapy (HT) and 7-field intensity-modulated radiotherapy (7F-IMRT) for cervical cancer. Methods Twenty-five patients with cervical cancer who underwent helical tomography between March 2015 and October 2017 were enrolled in this study. All enrolled patients were treated in prone position, with a full bladder. Both HT planning and 7F-IMRT planning were carried out for each patient. The dosimetry parameters of target areas and organs-at-risk, and monitor units (MU) were compared between two planning modes. Results HT plan was better than 7F-IMRT plan in conformity index and homogeneity index ［0.898±0.017 vs 0.834±0.013, P<0.001; 0.062±0.012 vs 0.109±0.019, P<0.001］. The D1 and D2 of planning target volume in HT group were lower than those in 7F-IMRT group (all P<0.001) , while Dmean, D98 and D95 in HT group were higher than those in 7F-IMRT group (P=0.048, P<0.001, P=0.015). The Dmax, Dmean, V30 and V40 of small intestine, colon, rectum and bladder and the V50 of rectum were significant lower (P<0.001, P<0.001, P<0.001, P=0.001, P=0.006), and the V50 of the other organs-at-risk was slightly lower (P=0.130) in HT group as compared with 7F-IMRT group. Moreover, the V25, D5, Dmean and Dmax of femoral heads in HT group were significantly lower than those in 7F-IMRT group (all P<0.001). However, compared with 7F-IMRT group, HT group had a much higher MU. Conclusion HT plan which ensures the target dose without increasing the radiotherapy toxicity is superior to 7F-IMRT plan in conformity index, homogeneity index and organs-at-risk sparing. However, the MU of HT plan is higher than that of 7F-IMRT plan, which indicates a lower utilization rate of beams in HT plan. As an image-guided radiotherapy technology, HT system is worthy of application for it can ensure the accuracy of each radiotherapy.
Last Update: 2019-01-24