Dosimetric comparison of two kinds of skin fluence expansion methods in intensity-modulated radiotherapy following radical mastectomy for breast cancer(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2020年第10期
- Page:
- 1237-1241
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Dosimetric comparison of two kinds of skin fluence expansion methods in intensity-modulated radiotherapy following radical mastectomy for breast cancer
- Author(s):
- BIN Shizhen1; ZHANG Junjun1; SHAN Dongyong1; CHENG Shulin1; ZHANG Ji1; TANG Tian1; LI Na2
- 1. Department of Oncology, the Third Xiangya Hospital of Central South University, Changsha 410013, China 2. Department of Radiology, the Third Xiangya Hospital of Central South University, Changsha 410013, China
- Keywords:
- Keywords: breast cancer intensity-modulated radiotherapy skin fluence expansion dosimetry
- PACS:
- R737.9；R811.1
- DOI:
- DOI:10.3969/j.issn.1005-202X.2020.10.005
- Abstract:
- Abstract: Objective To compare the dosimetric differences between two kinds of skin fluence expansion methods in intensity-modulated radiotherapy (IMRT) plan for breast cancer. Methods Twenty patients treated by IMRT after radical mastectomy for left-sided breast cancer were randomly enrolled in the study, and Nearest cell (NC) and Erosion-expansion (ED) provided by Varian Eclipse treatment planning system (Version 11.0) were separately used for skin fluence expansion to generate 8FIMRT-NC plan and 8FIMRT-ED plan. Dose-volume histograms, dose distributions of planning target volume (PTV) and organs-at-risk (OAR), plan verification passing rates and the total monitor units (MU) per fraction were compared between two groups of plans. Results The fluence and dose lines in both groups were expanded to the chest wall skin, and the dose distribution of PTV in both groups met the prescribed dose requirements. There was no significant difference in the Dmax, Dmean, V110%, conformity index, homogeneity index, gradient measurement of PTV between two groups. The doses of the main OAR such as lungs, heart and spinal cord were basically similar, without statistical differences. The difference in plan verification passing rate between two groups was trivial, and both two groups of plans could be applied to clinical treatment. However, the total MU per fraction in 8FIMRT-ED plan was lower than that in 8FIMRT-NC plan, with statistical significance ［(1 282.35±184.84) MU vs (1 302.05±195.37) MU t=2.590, P<0.05］. Conclusion In IMRT after radical mastectomy for breast cancer, both NC and ED can effectively expand the skin fluence, and the dose of PTV and OAR can meet the clinical treatment requirements. There was no significant dosimetric difference between two methods, but the total MU per fraction was less when using ED to expand the skin fluence.
Last Update: 2020-10-29