Effects of different field arrangements on the dose distribution of postoperative intensity-modulated radiotherapy for gastric cancer(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2019年第12期
- Page:
- 1400-1405
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Effects of different field arrangements on the dose distribution of postoperative intensity-modulated radiotherapy for gastric cancer
- Author(s):
- HU Zhigang; LIU Yongqiang; REN Jian; ZHANG Hong
- Department of Radiotherapy, Baoji Central Hospital, Baoji 721000, China
- Keywords:
- gastric cancer; intensity-modulated radiotherapy; field arrangement; dosimetry
- PACS:
- R815；R735.2
- DOI:
- DOI:10.3969/j.issn.1005-202X.2019.12.007
- Abstract:
- Abstract: Objective To investigate the effects of different field arrangements on the dose distribution of intensity-modulated radiotherapy (IMRT) after the operation for gastric cancer. Methods A total of 42 gastric cancer patients scheduled for postoperative radiotherapy were enrolled in the study. The plan schemes for enrolled gastric cancer patients included static 7-field IMRT (plan A, with beam orientations of 0°, 52°, 104°, 156°, 214°, 256°, 308°), static 5-field IMRT (plan B, with beam orientations of 0°, 72°, 144°, 216°, 288°) and static 4- field IMRT (plan C, with beam orientations of 20°, 90°, 180°, 310°). The differences in the doses to target areas and organs-at-risk as well as the conformity index and homogeneity index of target areas were compared among 3 plans with different field arrangements. Results The comparison on the doses to target areas and homogeneity index showed that there was no significant difference among different plans (P>0.05), but the conformity index of plan A was significantly higher than that of plans B and C (P<0.05). There were statistical differences in the Dmax and Dmean of spinal cord, the V30 and Dmean of liver, the V20 and Dmean of left and right kidney among 3 plans with different field arrangements (P<0.05). The Dmax and Dmean of spinal cord, the V30 of liver and the V20 of right kidney in plan A were superior to those in plan B (P<0.05), and the V30 and Dmean of liver as well as the V20 and Dmean of left and right kidney in plan C were significantly better than those in plans A and B (P<0.05). Conclusion Static 4-field IMRT as the postoperative radiotherapy for gastric cancer can better protect the organs-at-risk while ensuring the doses to target areas.
Last Update: 2019-12-24