Dosimetric impacts of multichannel applicator in three-dimensional brachytherapy for advanced cervical carcinoma
Lei Chengzhi, Huang Manni, Xu Yingjie, Xiong Suiyang, An Jusheng, Dai Jianrong, Wu lingying
Department of Gynecologic Oncology & Radiation Oncolcgy,Cancer Center/Cancer Hospital,Chinese Academy of Medical Science,Peking Union Medical College,Beijing 100021,China
Abstract：Objective To investigate the relationship between the channel design of tandem–and-ovoid (T&O) applicator and the doses to organs at risk (OARs) and target volume in three-dimensional brachytherapy for advanced cervical carcinoma. Methods The data on 15 patients with advanced cervical carcinoma treated with three-dimensional brachytherapy in our hospital from 2015 to 2016 were collected, and 30 randomly selected high-dose-rate titanium T&O plans were retrospectively studied. CT-guided, conformal brachytherapy plans were generated. To simulate T&O applicator, the tandem applicator was virtually compared with the T&O plans with the target volume and OARs remaining unchanged. The DVH parameters of the rectum, bladder, and sigmoid were compared using the paired t test. Results For T&O plans and tandem applicator plans, the mean D2cc of the rectum was 387.8±96.8 cGy and 340.8±88.1 cGy, respectively;the mean D2cc of the bladder was 443.2±87.5 cGy and 719.4±243.0 cGy, respectively;the mean D2cc of the sigmoid was 330.3±88.8 cGy and 383.1±105.6 cGy, respectively. In the T&O plans, the doses to the rectum, bladder, and sigmoid were within the limits (rectum:D2cc≤500 cGy;bladder:D2cc≤550 cGy;sigmoid:D2cc≤500 cGy), while D2cc of the bladder and sigmoid was higher or partially higher than the limits. T&O plans showed a significant reduction in bladder D2cc and sigmoid D2cc compared with the tandem applicator plans (all P<0.05). Conclusions Compared with tandem applicator plans, plans using T&O applicator provide significant sparing of bladder and sigmoid tissues in three-dimensional brachytherapy for cervical carcinoma, but the toxicities require further investigation.
Lei Chengzhi,Huang Manni,Xu Yingjie et al. Dosimetric impacts of multichannel applicator in three-dimensional brachytherapy for advanced cervical carcinoma[J]. Chinese Journal of Radiation Oncology, 2017, 26(4): 414-418.
[1] Haie-Meder C,P?tter R,Van Limbergen E,et al. Recommendations from Gynaecological (GYN) GEC-ESTRO Working Group (I):concepts and terms in 3D image based 3D treatment planning in cervix cancer brachytherapy with emphasis on MRI assessment of GTV and CTV[J].Radiother Oncol,2005,74(3):235-245.DOI:10.1016/j.radonc.2004.12.015 [2] P?tter R,Haie-Meder C,Van Limbergen E,et al. Recommendations from gynaecological (GYN) GEC ESTRO working group (Ⅱ):concepts and terms in 3D image-based treatment planning in cervix cancer brachytherapy-3D dose volume parameters and aspects of 3D image-based anatomy,radiation physics,radiobiology[J].Radiother Oncol,2006,78(1):67-77.DOI:10.1016/j.radonc.2005.11.014 [3] Hellebust TP,Kirisits C,Berger D,et al. Recommendations from Gynaecological (GYN) GEC-ESTRO Working Group:considerations and pitfalls in commissioning and applicator reconstruction in 3D image-based treatment planning of cervix cancer brachytherapy[J].Radiother Oncol,2010,96(2):153-160.DOI:10.1016/j.radonc.2010.06.004 [4] Dimopoulos JCA,Petrow P,Tanderup K,et al. Recommendations from Gynaecological (GYN) GEC-ESTRO Working Group (IV):basic principles and parameters for MR imaging within the frame of image based adaptive cervix cancer brachytherapy[J].Radiother Oncol,2012,103(1):113-122.DOI:10.1016/j.radonc.2011.12.024 [5] Park SJ,Chung M,Demanes DJ,et al. Dosimetric comparison of 3-dimensional planning techniques using an intravaginal multichannel balloon applicator for high-dose-rate gynecologic brachytherapy[J].Int J Radiat Oncol Biol Phys,2013,87(4):840-846.DOI:10.1016/j.ijrobp.2013.08.008 [6] Vinod SK,Caldwell K,Lau A,et al. A comparison of ICRU point doses and volumetric doses of organs at risk (OARs) in brachytherapy for cervical cancer[J].J Med Imaging Radiat Oncol,2011,55(3):304-310.DOI:10.1111/j.1754-9485.2011.02272.x [7] Hellebust TP,Tanderup K,Lervg C,et al. Dosimetric impact of interobserver variability in MRI-based delineation for cervical cancer brachytherapy[J].Radiother Oncol,2013,107(1):13-19.DOI:10.1016/j.radonc.2012.12.017 [8] Janjan NA,Yasko AW,Reece GP,et al. Comparison of charges related to radiotherapy for soft-tissue sarcomas treated by preoperative external-beam irradiation versus interstitial implantation[J].Ann Surg Oncol,1994,1(5):415-422.DOI:10.1007/BF02303815 [9] Fokdal L,Tanderup K,Hokland SB,et al. Clinical feasibility of combined intracavitary/interstitial brachytherapy in locally advanced cervical cancer employing MRI with a tandem/ring applicator in situ and virtual preplanning of the interstitial component[J].Radiother Oncol,2013,107(1):63-68.DOI:10.1016/j.radonc.2013.01.010.
2017, Vol. 26 
