RESUMO
Objective:Investigate the safety and feasibility of using the new self-designed implanting applicator in vaginal three-dimensional intracavitary brachytherapy after hysterectomy for gynecological cancer, and to explore the clinical value of the self-designed implanting applicator.Methods:Sixty-two gynecological cancer patients who underwent brachytherapy in Sun Yat-sen University Cancer Center were selected in this study. Each patient received three-dimensional intracavitary brachytherapy because of the indication of postoperative radiotherapy. Each patient was treated with different types of self-designed implanting applicators according the condition of postoperative vagina,and the vaginal tube and implant needle were placed in the template according to the preset channnel. Based on the actual CT images, the high-risk clinical target volume (HR-CTV), and organs at risk were defined according to unified target area delineation criteria and then the brachytherapy plan was conducted. The prescription dose of high-risk clinical target volume (HR-CTV) was 5.5 Gy/time. The parameters such as target area, organs at risk volume and irradiated dose were evaluated by DVH diagram.Results:Sixty-two patients successfully completed brachytherapy under the guidance of self-designed implanting applicator. A total of 140 implantation treatments were performed. The total average dose of HR-CTV D90% was (575.48±22.30) cGy, the mean dose D 2cm3 of bladder, rectum and sigmoid colon were (328.69±102.71), (369.14±46.59) and (27.28±71.27) cGy, the small intestine did not drop the target area, so there was no statistics. There was statistical significance between target volume and organs at risk dose ( P<0.05). Conclusions:The new self-designed implanting applicator has obvious clinical advantages in vaginal three-dimensional intracavitary brachytherapy after hysterectomy for gynecological cancer, meets the requirements of the preset planning dose,and it is sample to operate and highly safe,which indicated a bright future of the clinical application.