CT图像引导在宫颈癌腔内放疗中的应用

Role of Computed Tomography Image Guidance in Two-dimensional Brachytherapy of Cervical Cancer

目的探讨CT图像引导在宫颈癌腔内放疗中的应用价值。方法前瞻性纳入2013年4月至8月间本科收治的所有需用Fletcher施源器治疗的宫颈癌患者共92例,首次腔内放疗施源器置入术后,治疗计划设计前行CT扫描。三维方向测量CT图像中宫腔管长度及宫体倾角,记录子宫穿孔及其他施源器位置不佳病例并归类分析。结果 92例患者中有3例发生子宫穿孔,发生率为3.3%,均为无症状性,为所有患者中子宫后倾角度最大的3例。其他施源器位置不佳患者26例(28.3%),其中宫腔管距宫底距离过近且邻近小肠者13例,宫腔管位置偏离宫腔中心未达穿孔者9例,宫腔管距离宫底过远者4例。发现施源器位置得当,但宫体小且被乙状结肠包绕距离过近者1例。结论将CT模拟影像引入二维腔内放疗定位能及时发现子宫穿孔及其他施源器位置不佳情况,据此调整二维腔内放疗计划并指导下次施源器置入角度,方便快捷,可在临床推广应用。

Objective To evaluate the value of computed tomography （CT） image guidance in two-di- mensional brachytherapy of cervical cancer. Methods A total of 92cervical cancer patients who were treated by Fletcher applicator in our hospital from April to August 2013 were enrolled in this prospective study. CT scan was required for all patients before the performance of first brachytherapy. We measured the length and angle of uter- ine, recorded the cases of uterus perforation and other poor positions of applicators, and then analyzed by classifi- cation. Results Among these 92 cases, uterine perforation occurred in 3 cases （3.3 % ）. All these three pa- tients were asymptomatic and the angles of their uteruses were largest among all patients. Twenty-six cases （28.3%） had poor positions of applicators, which included tandems too close to the bottom of uterine and adja- cent to small intestine （ n = 13 ）, tandems deviated from the center of uterine cavity excluding uterine perforation （ n = 9）, and tandems too far away from the bottom of uterine （ n = 4）. In one case, the position of applicator was appropriate, but the uterus was too small and surrounded by sigmoid colon. Conclusions Asymptomatic uterine perforation and other poor positions of applicators can be found by CT scan during brachytherapy, which provides useful information for adjusting the performance of two-dimensional brachytherapy. As an easy and convenient technique, it can be widely applied in clinical practice.