Target delineation and dosimetry analysis of 125I interstitial brachytherapy for recurrent adenoid cystic carcinoma in the parotid gland
10.3760/cma.j.issn.0254-5098.2021.09.006
- VernacularTitle:125I放射性粒子治疗腮腺复发性腺样囊性癌的靶区设计及剂量学分析
- Author:
Shuang DONG
1
;
Shuming LIU
;
Jie ZHANG
;
Lei ZHENG
;
Yan SHI
;
Xiaoming LYU
;
Guangyan YU
;
Jianguo ZHANG
Author Information
1. 北京大学口腔医学院·口腔医院 口腔颌面外科，口腔数字化医疗技术和材料国家工程实验室，口腔数字医学北京市重点实验室，北京 100081
- Keywords:
125I radioactive seeds;
Adenoid cystic carcinoma in the parotid gland;
Dosimetry
- From:
Chinese Journal of Radiological Medicine and Protection
2021;41(9):672-677
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze the target design and dosimetric parameters of patients with recurrent adenoid cystic carcinoma (ACC) in the parotid gland who were treated with 125I interstitial brachytherapy alone. Methods:A retrospective analysis was conducted for 25 patients with recurrent adenoid cystic carcinoma in parotid gland who were histopathologically diagnosed between January 2015 and October 2019. These patients were treated with 125I interstitial brachytherapy alone, with prescribed doses of 100-120 Gy. The target volume was designed according to the pathological characteristics of ACC and recurrence sites. The pre- and post-operation dosimetric parameters (i.e., local control rates) were calculated using the treatment planning system. Results:In this study, the local recurrence sites included the superficial lobe (10/25) and deep lobe (7/25) of the parotid gland primarily and the skull base region (four patients) and mastoid posterior region (four patients) secondarily. The number of 125I seeds ranged from 16 to 111, with a median number of 59. The activity of radioactive particles was 18.5-25.9 MBq. The 3- and 5-year local control rates were 81.5% and 61.5%, respectively. No significant differences were found between pre- and post-operative dosimetric parameters such as D90, V100, and V150. There was no significant difference in local control rates among the four different recurrence sites. Conclusions:125I interstitial brachytherapy is proven to be an effective approach in the treatment of recurrent adenoid cystic carcinoma in the parotid gland. Satisfying local control rates can be achieved through target delineation performed according to recurrence sites and perineural invasion characteristics of ACC.
