Dosimetric analysis of 3D-printed minimally invasive-guided template in the brachytherapy treatment of locally advanced cervical cancer
10.3760/cma.j.issn.0254-5098.2020.07.005
- VernacularTitle:3D打印模板应用于局部晚期宫颈癌后装放疗的剂量学研究
- Author:
Yongxia ZHANG
1
;
Xiangkun YUAN
;
Junjun MIAO
;
Guangying HOU
;
Yuanyuan CHEN
;
Qiong LIU
;
Huanhuan LYU
Author Information
1. 河北省沧州中西医结合医院放化疗二科 061000
- From:
Chinese Journal of Radiological Medicine and Protection
2020;40(7):519-523
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the dosimetry advantage of 3D-printed minimally invasive guided template used in local advanced cervical cancer intracavitary combined with interstitial radiotherapy.Methods:A total of 68 cases with locally advanced cervical cancer who were admitted to Hebei Cangzhou Hospital of intergrated traditional Chinese medicine and western medicine from May 2016 to August 2019 were selected. All the patients had eccentric tumor or large tumor (tumor diameter >5 cm) after radiotherapy. Intensity modulated radiotherapy was used for external radiotherapy, and intracavitary combined with interstitial radiotherapy was used for brachytherapy. The prescription dose of high-risk clinical target volume (HR-CTV) is 6 Gy/fraction, once a week, five fractions in total. Sixty-eight patients were randomly divided into two groups, 35 cases in the template group who received minimally invasive 3D printing guided template assisted intrauterine tube implantation and insertion needle implantation, and 33 patients in the free implantation group who received free hand intrauterine tube implantation and insertion needle implantation. The position and depth of the insertion needle were adjusted by CT-guidance, and the final CT image was transmitted to the Oncentra Brachy treatment planning system, then the target volume and organs at risk were delineated for planning and treatment.Results:A total of 340 brchytherapy plans were made, including 175 in the template group and 165 in the free implantation group. The D90 values of the HR-CTV and intermediate-risk clinical target volume (IR-CTV) in the template group were increased ( t=3.63, 2.45, P<0.05), and D2 cm3 values (dose of 2 cm 3 of organ at risk) of bladder, rectum and sigmoid colon were significantly decreased ( t=-2.81, -2.54, -2.33, P<0.05). At the same time, the average CT scanning times of each treatment in the template group was (1.78±0.53) times, the average duration of each treatment was (11.35±3.98) min, and the average number of needles used in each implant treatment was (5.21±1.37). The result of free implantation group was higher than that of the template group. The differences were statistically significant ( t=-2.26, -4.53, -3.21, P<0.05). Conclusions:For localized advanced cervical cancer patients with eccentric or large tumors, the 3D printed minimally invasive guided template for intracavitary and interstitial implantation has obvious dosimetry advantages, and the operation is simpler and the duration is shorter.