Different fixed-field intensity-modulated radiotherapy plans for breast cancer: a dosimetric comparison(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2018年第11期
- Page:
- 1269-1275
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Different fixed-field intensity-modulated radiotherapy plans for breast cancer: a dosimetric comparison
- Author(s):
- WANG Lei1; NI Xinye2; WANG Genhe1; CHEN Weiping1; FANG Ping1; WU Yiqing1; JIANG Dahua1; CHENG Wentao1
- 1. Department of Radiation Oncology, Huangshan City People’s Hospital, Huangshan 245000, China; 2. Department of Radiation Oncology, Changzhou Second People’s Hospital, Changzhou 213003, China
- Keywords:
- ; Keywords: breast cancer; intensity-modulated radiotherapy; number of field; dosimetry
- PACS:
- R811.1
- DOI:
- DOI:10.3969/j.issn.1005-202X.2018.11.006
- Abstract:
- Abstract: Objective To compare the dose distribution in 4 different plans for the modified radical mastectomy of breast cancer for selecting an optimal treatment strategy with a high target coverage, good homogeneity, better conformity index and less doses to the normal tissues. Methods A total of 16 patients with breast cancer after radical mastectomy were randomly selected, and 4 different treatment plans, namely 4-field (4F), 5-field (5F), 6-field (6F) and hybrid intensity-modulated radiotherapy (IMRT), were designed for each patient. The doses of target areas and organs-at-risk were compared among 4 different treatment plans. Results The conformity index of Hybrid-IMRT, 5F-IMRT and 6F-IMRT was better than that of 4F-IMRT, with statistical differences (P<0.05), and no statistical differences were found in conformity index among Hybrid-IMRT, 5F-IMRT and 6F-IMRT (P>0.05). The homogeneity index of 4F-IMRT, 5F-IMRT, 6F-IMRT and Hybrid-IMRT was 0.22, 0.22, 0.21 and 0.16, respectively, without statistical differences (P>0.05). Hybrid-IMRT and 4F-IMRT were superior to 5F-IMRT and 6F-IMRT in the V5 of ipsilateral lung, and the V20 of ipsilateral lung in Hybrid-IMRT plan were better than that in the other plans (P<0.05). The V30 of ipsilateral lung was significantly lower in Hybrid-IMRT than in 4F-IMRT and 6F-IMRT (P<0.05), but there was no significant difference among other treatment plans (P>0.05). The Dmean of ipsilateral lung in Hybrid-IMRT was significantly higher than 5F-IMRT and 6F-IMRT, with statistical differences (P<0.05), and there was no statistical difference between Hybrid-IMRT and 4F-IMRT plans (P>0.05). No significant differences were found among 4 plans in the V30 and V40 of heart. The Dmean of heart in Hybrid-IMRT and 4F-IMRT was lower than that in 5F-IMRT and 6F-IMRT, with statistical differences (P<0.05). No significant differences were found in the Dmax of the spinal cord among 4 plans. 4F-IMRT was inferior to the other 3 plans in the Dmean of thyroid, with statistical differences (P<0.05). The monitor unit was found to be highest in 6F-IMRT, followed by 4F-IMRT, 5F-IMRT and Hybrid-IMRT. Conclusion Hybrid-IMRT plan which can remarkably improve the dose distribution of target areas, without increasing the radiation dose of organs-at-risk should be further promoted in clinic.
Last Update: 2018-11-22