乌德勒支施源器在宫颈癌3D-IGBT应用观察

目的 观察乌德勒支施源器在局部晚期宫颈癌3D-IGBT中的临床应用情况,揭示其在IC-IS的应用规律。方法 回顾分析45例接受根治性放疗的局部晚期宫颈癌患者,外照射后行3D-IGBT,其中45例130次IC-IS入组。将满足计划目标剂量分次定义为A组(37例86人次),余为B组(22例44人次),成组t检验差异。结果 施源器使用15、20、25 mm卵圆体的频率分别为50.0%、20.0%、30.0%,30 mm型号无使用。共置插植针499根,6、7、10、11孔位使用频率分别为23.1%、21.2%、21.2%、24.1%。A组平均插植针数为3.7根明显少于B组4.2根(P=0.008)。A组的HR-CTV平均体积为(40.71±18.43) cm³小于B组(51.81±14.74) cm³(P=0.001),A组HR-CTV的宽和高小于B组(P=0.011、0.006);而厚相似(P=0.595)。高与插植深度的差两组相似(P=0.366),宽与左右针孔间距的差A组小于B组(P=0.007)。结论 局部晚期宫颈癌行IC-IS时,乌德勒支施源器的卵圆体多选用25 mm及以下型号,插植孔位多选用6、7、10、11号。在插植针数≥4根、深度≥3 cm时,宽度是影响计划剂量的主要因素。

The clinical application research of Utrecht applicator in three-dimensional image guided brachytherapy (3D-IGBT) for cervical cancer

Objective To investigate the clinical application of Utrecht applicator in three-dimensional image-guided brachytherapy (3D-IGBT) for locally advanced cervical cancer,as well as its application discipline in intracavitary/interstitial (IC/IS) therapy.Methods A retrospective analysis was performed for the clinical data of 45 patients with locally advanced cervical cancer who received radical radiotherapy,and the patients received external beam radiotherapy followed by 3D-IGBT.A total of 130 times (n =45) of IC/IS therapy were performed,and the patients who received such therapy were all enrolled.The patients who met the target dose fractionation defined in the plan were enrolled as group A (n=37,86 times),and the other patients were enrolled as group B (n=22,44 times).Two groups difference was analyzed with Group t-test.Results The frequencies of use of 15-,20-,and 25-mm ovoids by the applicator were 50.0％,20.0％,and 30.0％,respectively,and the 30-mm ovoid was not used.A total of 499 needles were used,and the frequencies of use of 6,7,10,and 11 insertion holes were 23.1％,21.2％,21.2％,and 24.1 ％,respectively.Group A had a significantly lower mean number of the needles than group B (3.7 vs.4.2,P=0.008).Compared with group B,group A had a significantly lower mean high-risk clinical target volume (CTV)(40.71±18.43 cm3 vs.51.81±14.74 cm3,P=0.001),as well significantly lower width and height of high-risk CTV (P=0.011 and 0.006),but the thickness of high-risk CTV was similar between the two groups (P=0.595).The difference between height and insertion depth (DH) was similar between the two groups (P=0.366).Group A had a smaller difference between width and pinhole distance Dw than group B (P=0.007).Conclusions When IC/IS therapy is performed for locally advanced cervical cancer,the 15-,20-,and 25-mm ovoids of Utrecht applicator and 6,7,10,and 11 insertion holes are frequently used.When the number of needles is no less than 4 and the depth is no less than 3 cm,width is the major factor which affects the planned dose.