Dosimetric study on different bladder filling status in cervical cancer radiotherapy based on artificial intelligence-assisted segmentation
10.3969/j.issn.1005-202X.2025.07.002
- VernacularTitle:基于人工智能辅助勾画的宫颈癌放疗不同膀胱充盈度的剂量学研究
- Author:
Yingnan QI
1
;
Xuemei CHEN
1
;
Foping CHEN
1
;
Zhanlin CHEN
1
;
Xiaobo JIANG
1
;
Senkui XU
1
;
Yu LUO
1
;
Xiaoyue XIONG
1
;
Feng CHI
1
Author Information
1. 华南恶性肿瘤防治全国重点实验室/广东省恶性肿瘤临床医学研究中心/中山大学肿瘤防治中心放疗科,广东 广州 510060
- Publication Type:Journal Article
- Keywords:
cervical cancer;
bladder filling status;
artificial intelligence-assisted segmentation;
cone-beam computed tomography;
dosimetry
- From:
Chinese Journal of Medical Physics
2025;42(7):847-852
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the dosimetric impact of interfractional bladder fullness variation in volumetric modulated arc therapy for cervical cancer using artificial intelligence-assisted cone-beam CT(CBCT)image segmentation,and propose an imaging-based quantitative assessment criterion for bladder fullness,providing an objective basis for assessing bladder filling status during clinical treatment.Methods Fifty patients receiving volumetric modulated arc therapy for cervical cancer were selected.The criterion for determining bladder fullness was as follow:if the bladder longitudinal diameter measured on the CBCT mid-sagittal plane was greater than half of the bladder longitudinal diameter measured on the localizable CT,it was defined as≥50%bladder fullness;otherwise,it was defined as<50%bladder fullness.Based on this criterion,two CBCT images were selected for each patient(representing fractions with≥50%and<50%fullness,respectively).Borui auto-contouring system was applied to re-contour the target areas and organs at risk,followed by dose recalculation.Results Compared with≥50%bladder fullness group,<50%bladder fullness group had significantly increased bladder V40,and small bowel Dmax,Dmean,V55,V45,V40(P<0.05),indicating that during interfractional radiotherapy,a CBCT-measured bladder longitudinal diameter less than half of the bladder longitudinal diameter measured on the localizable CT could serve as a predictor for significantly increased radiation dose to the bladder and small bowel.Correlation analysis revealed that bladder volume change showed a positive correlation with bladder Dmax change(R=0.45),a significant negative correlation with bladder V30(R=-0.37),and negative correlations with small bowel Dmax,Dmean,V55,V45,V40(R=-0.31,-0.41,-0.39,-0.49,-0.61).The correlation results indicate that increasing bladder fullness could reduce the radiation dose to the bladder and small bowel.Conclusion Artificial intelligence-assisted segmentation confirms that in interfractional radiotherapy for cervical cancer,when the CBCT-measured bladder longitudinal diameter is less than half of the longitudinal diameter measured on the localizable CT,there is a significant increase in radiation dose to OAR.Maintaining an ideal state of bladder fullness contributes to reducing the radiation dose to the bladder and small bowel.It is crucial to provide patients with adequate bladder management education before treatment and implement strict bladder volume management strategies during treatment fractions.
