AbstractObjective To investigate the impacts of ring applicator (Nucletron#090.617) reconstruction uncertainties on the radiation dose of computed tomography-guided three-dimensional (3D) brachytherapy for cervical cancer. Methods Twenty patients with cervical cancer who completed radical treatment were enrolled as subjects. In a treatment planning system, dose distribution was simulated with reconstruction uncertainties of tandem applicator, ring applicator, and both tandem and ring applicators, respectively. Two directions of reconstruction uncertainties were towards the tip (+) and the connector end (-) of the applicator. Reconstruction uncertainties of ±1 mm, ±2 mm, and ±3 mm were simulated. The D100, D90, and D50 for clinical target volume (CTV) and D0.1cc, D1cc, and D2cc for the bladder, rectum, and small intestine were evaluated. The effects of applicator reconstruction uncertainties on radiation dose of 3D brachytherapy were analyzed. Results The tandem applicator had greater impacts on radiation dose than the ring applicator. The dose deviation due to applicator reconstruction uncertainties increased with the increase in volume for CTV parameters but decreased with the increase in volume for parameters of organs at risk. The impacts of applicator reconstruction uncertainties were greatest on the dose to the small intestine. The deviation due to 3 mm reconstruction uncertainty of tandem applicator, ring applicator, and both tandem and ring applicators was 0.90%, 1.62%, and 1.74% for D90 of CTV, 1.33%, 1.53%, and 1.78% for D2cc of the bladder, 0.89%, 1.85%, and 1.97% for D2cc of the rectum, and 0.86%, 3.04%, and 3.50% for D2cc of the small intestine, respectively. Conclusions Applicator reconstruction uncertainties have certain impacts on the radiation dose of 3D brachytherapy. In order to improve the accuracy of brachytherapy, comprehensive quality control is recommended for applicator reconstruction.
Corresponding Authors:
Wang Pei,Email;dengwangpei@163.com
Cite this article:
Wang Xianliang,Yuan Ke,Kang Shengwei et al. Impacts of ring applicator reconstruction uncertainties on radiation dose in patients with cervical cancer[J]. Chinese Journal of Radiation Oncology, 2017, 26(3): 316-319.
Wang Xianliang,Yuan Ke,Kang Shengwei et al. Impacts of ring applicator reconstruction uncertainties on radiation dose in patients with cervical cancer[J]. Chinese Journal of Radiation Oncology, 2017, 26(3): 316-319.
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