Dosimetric comparison of Hybrid-IMRT vs IMRT for radiotherapy with simultaneous integrated boost for brain metastases(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2020年第6期
- Page:
- 671-675
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Dosimetric comparison of Hybrid-IMRT vs IMRT for radiotherapy with simultaneous integrated boost for brain metastases
- Author(s):
- ZENG Rong; CHEN Peng; WANG Jie; JIANG Qi; WANG Shanghu; MIN Xuhong
- Department of Radiation Oncology, Anhui Chest Hospital, Hefei 230022, China
- Keywords:
- Keywords: brain metastasis hybrid intensity-modulated radiotherapy intensity-modulated radiotherapy simultaneous integrated boost dosimetry
- PACS:
- R739.41；R811.1
- DOI:
- DOI:10.3969/j.issn.1005-202X.2020.06.003
- Abstract:
- Abstract: Objective To explore the dosimetric differences between intensity-modulated radiotherapy (IMRT) and Hybrid-IMRT which combining three-dimensional conformal radiotherapy and IMRT for radiotherapy with simultaneous integrated boost for brain metastases. Methods Hybrid-IMRT plan and IMRT plan were designed for 20 patients with brain metastases. Hybrid-IMRT plan included 3 600 cGy/20 F to the whole brain by 2 horizontal irradiation fields in three-dimensional conformal radiotherapy and 5 000 cGy/20 F to brain metastases by IMRT with simultaneous integrated boost. In IMRT plan, 3 600 cGy/20 F was given to the whole brain and 5 000 cGy/20 F to brain metastases. On the premise of meeting the clinical requirements, the dosimetric parameters between Hybrid-IMRT and IMRT were compared. The dosimetric parameters included the conformity index (CI), homogeneity index and mean dose of target areas, monitor units, the maximum dose and mean dose of organs-at-risk such as brain stem, optic nerves, lens, optic chiasm and eyeballs. Results Both IMRT plan and Hybrid-IMRT plan met the clinical requirements. The homogeneity index of PGTV in Hybrid-IMRT plan was lower than IMRT plan (P<0.001). The maximum dose and mean dose of brain stem, optic chiasm and lens, and the mean dose of eyeballs and the maximum dose of optic nerves in Hybrid-IMRT plan were lower than those in IMRT plan (P<0.05). Moreover, the monitor units in Hybrid-IMRT plan was decreased by about 70% as compared with IMRT plan (P<0.001). Conclusion Both plans meet the clinical requirements, but Hybrid-IMRT plan is advantageous over IMRT plan in homogeneity index, treatment time and organs-at-risk sparing.
Last Update: 2020-07-03