摘要
目的 探讨中晚期宫颈癌三维后装腔内放疗中三通道施源器的通道设计与OAR、靶区剂量间关系.方法 调取2015-2016年我院三维腔内治疗的15例中晚期宫颈癌数据,其中30次“阴道卵形两半球+宫腔管”的三通道施源器剂量参数纳入研究.在原靶区和OAR勾画、处方剂量不变基础上保留宫腔管单通道施源器,重新进行三维腔内照射设计的剂量参数作为对照组,配对t检验两组OAR剂量参数.结果 三通道、单通道施源器组直肠D2cc分别为(387.8±96.8)、(340.8±88.1)cGy;两组膀胱和乙状结肠D2cc分别为(443.2±87.5)、(719.4±243.0) cGy和(330.3±88.8)、(383.1±105.6) cGy.三通道组满足直肠(D2cc≤500 cGy)、膀胱(D2cc≤550 cGy)和乙状结肠(D2cc≤500 cGy)计划限量,单通道组膀胱和乙状结肠D2cc受量分别为大于和部分大于计划限量.单通道组膀胱和乙状结肠D2cc受量高于三通道组(P均<0.05).结论 宫颈癌三维腔内放疗中“阴道卵形两半球+宫腔管”三通道施源器比宫腔管单通道可有效降低膀胱和乙状结肠受量,有利于计划优化和剂量实施.
Objective To investigate the relationship between the channel design of tandem-andovoid (T&O) applicator and the doses to organs at risk (OARs) and target volume in three-dimensional brachytherapy for advanced cervical carcinoma.Methods The data on 15 patients with advanced cervical carcinoma treated with three-dimensional brachytherapy in our hospital from 2015 to 2016 were collected,and 30 randomly selected high-dose-rate titanium T&O plans were retrospectively studied.CT-guided,conformal brachytherapy plans were generated.To simulate T&O applicator,the tandem applicator was virtually compared with the T&O plans with the target volume and OARs remaining unchanged.The DVH parameters of the rectum,bladder,and sigmoid were compared using the paired t test.Results For T&O plans and tandem applicator plans,the mean D2cc of the rectum was 387.8±96.8 cGy and 340.8±88.1 cGy,respectively;the mean D2cc of the bladder was 443.2± 87.5 cGy and 719.4± 243.0 cGy,respectively;the mean D2cc of the sigmoid was 330.3±88.8 cGy and 383.1±105.6 cGy,respectively.In the T&O plans,the doses to the rectum,bladder,and sigmoid were within the limits (rectum:D2cc ≤ 500 cGy;bladder:D2cc ≤ 550 cGy;sigmoid:D2c ≤ 500 cGy),while D2cc of the bladder and sigmoid was higher or partially higher than the limits.T&O plans showed a significant reduction in bladder D2cc and sigmoid D2cc compared with the tandem applicator plans (all P<0.05).Conclusions Compared with tandem applicator plans,plans using T&O applicator provide significant sparing of bladder and sigmoid tissues in three-dimensional brachytherapy for cervical carcinoma,but the toxicities require further investigation.
出处
《中华放射肿瘤学杂志》
CSCD
北大核心
2017年第4期414-418,共5页
Chinese Journal of Radiation Oncology
基金
北京希望马拉松专项基金资助(LC2014A09)
关键词
宫颈肿瘤/三维腔内放疗
腔内施源器
剂量学
Cervical neoplasms/three-dimensional brachytherapy
Intracavitary applicator
Dosimetry