Dong Jie,Wang Donghui,Li Zhenghuan,et al.Dosimetric effects of prone immobilization devices combined with a belly-board in intensity-modulated radiotherapy for gynecologic cancers[J].Chinese Journal of Radiological Medicine and Protection,2023,43(1):23-29 |
Dosimetric effects of prone immobilization devices combined with a belly-board in intensity-modulated radiotherapy for gynecologic cancers |
Received:September 23, 2022 |
DOI:10.3760/cma.j.cn112271-20220923-00385 |
KeyWords:Gynecologic cancer Radiotherapy Prone immobilization device Dose distribution Anthropomorphic phantom |
FundProject:中国博士后科学基金面上项目(2019M6632);广东省基础与应用研究基金区域联合基金-青年基金项目(2021A1515111084) |
Author Name | Affiliation | E-mail | Dong Jie | Department of Radiation Oncology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China | | Wang Donghui | Department of Radiation Oncology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China | | Li Zhenghuan | Department of Radiation Oncology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China | | Kong Fantu | Department of Radiation Oncology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China | | Chen Luxi | Department of Radiation Oncology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China | | Yan Huamei | Department of Radiation Oncology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China | | Xu Xiangying | Department of Radiation Oncology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China | lifz1977@163.com |
|
Hits: 2835 |
Download times: 1363 |
Abstract:: |
Objective To investigate the dosimetric effects of prone immobilization devices combined with a belly board (PIDBBs) in the intensity-modulated radiotherapy (IMRT) for gynecologic cancers.Methods A total of 20 patients with cervical or endometrial cancer treated with radiotherapy in the Third Affiliated Hospital of Sun Yat-sen University from August 2020 to June 2021 were retrospectively analyzed. Two sets of body contours were outlined for each patient. One set of body contours did not contain the immobilization devices, and the other contour set included the immobilization devices. For each patient, doses were calculated for the two sets of contours using the same 7-field IMRT plan and were recorded as Planwithout and Planwith. The dosimetric difference caused by the immobilization devices was assessed by comparing the parameter values in the dose-volume histograms (DVHs) and by plan subtraction. The Gafchromic EBT3 film and anthropomorphic phantom were used to verify the calculated doses.Results The target coverage and average dose of Planwith were lower than those of Planwithout. Specifically, the V50 Gy, V49 Gy, and Dmean of planning target volume (PTV) decreased by 19.75%, 7.99%, and 2.54% (t=8.96, 10.49, 22.09, P<0.01), respectively. The V40 Gy, V30 Gy, V20 Gy, V15 Gy, and Dmean of skins increased by 51.79%, 51.05%, 45.72%, 33.63% and 10.80% (t=-2.54, -5.63, -15.57, -24.06, -13.88, P<0.01), respectively. Doses to other organs at risk (OARs) showed no significant differences. As indicated by the EBT3 measurements, the doses to skins of the abdomen and pelvis on the anthropomorphic phantom increased by approximately 37.24% (t=10.86, P<0.01).Conclusions Although PIDBBs can effectively reduce the low dose to the small intestine, the radiation attenuation caused by them can reduce the PTV coverage of radiotherapy plans and increase the doses to abdominal and pelvic skins sharply, especially for patients requiring irradiation of the groin and perineum. |
HTML View Full Text View/Add Comment Download reader |
Close |
|
|
|