Wang Fang, Bu Luyi, Wu Qun, Jiang Xue, Wu Lingyun, Li Yu, Xi Bin, Lu Zhongjie, Yan Senxiang
Department of Radiotherapy, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
Department of General Surgery, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
J Contemp Brachytherapy. 2020 Aug;12(4):367-374. doi: 10.5114/jcb.2020.98117. Epub 2020 Aug 21.
The objective of this study was to compare and assess the accuracy of computed tomography (CT)-based target delineation with that of magnetic resonance imaging (MRI)-based on high-dose-rate brachytherapy (HDR-BT) for patients with cervical cancer.
Data of 20 patients with locally advanced cervical cancer were collected and evaluated. Dimensions, conformity, and dose parameters of high-risk clinical target volume (CTV) as well as D, D, and D of organs at risk (OARs) based on MRI were compared with those based on CT.
Average age of 20 patients included was 57.8 years. Width, thickness, and volumes of CT-based CTV (CTV-CT) were significantly overestimated compared with those of MRI-based CTV (CTV-MR). Mean values of dice similarity coefficient (DSC), Hausdorff distance (HD), and centroid distance (ΔV) of CTV were 0.82 cm, 0.96 cm, and 0.35 cm, respectively. Dose values of CTV-CT were significantly lower compared with those of CTV-MR. Concerning OARs, geometrical and dosimetric values on CT were comparable to those on MRI.
The delineated ranges of CTV were significantly over-estimated on CT compared with MRI. D and D of CTV-CT were lower than CTV-MR. DSC and ΔV of CTV and CTV were similar to each other; however, there was a difference in terms of HD. CT images regarding pre-BT MR images for delineating were not enough and MRI fusion is still required.
本研究的目的是比较和评估基于计算机断层扫描（CT）的靶区勾画与基于磁共振成像（MRI）的宫颈癌高剂量率近距离放疗（HDR-BT）的准确性。
收集并评估20例局部晚期宫颈癌患者的数据。将基于MRI的高危临床靶区（CTV）的尺寸、适形性和剂量参数以及危及器官（OARs）的D、D和D与基于CT的进行比较。
纳入的20例患者的平均年龄为57.8岁。与基于MRI的CTV（CTV-MR）相比，基于CT的CTV（CTV-CT）的宽度、厚度和体积被显著高估。CTV的骰子相似系数（DSC）、豪斯多夫距离（HD）和质心距离（ΔV）的平均值分别为0.82 cm、0.96 cm和0.35 cm。CTV-CT的剂量值显著低于CTV-MR。关于OARs，CT上的几何和剂量学值与MRI上的相当。
与MRI相比，CT上CTV的勾画范围被显著高估。CTV-CT的D和D低于CTV-MR。CTV和CTV的DSC和ΔV彼此相似；然而，在HD方面存在差异。用于勾画的BT前MR图像的CT图像不够，仍需要MRI融合。
