Four-dimensional computed tomography scan analysis of liver tumor motion treated with abdominal compression during stereotactic treatment
10.3760/cma.j.cn113030-20210302-00084
- VernacularTitle:腹部加压控制下肝脏病灶移动度分析
- Author:
Ying ZHAO
1
;
Yuan TANG
;
Wenyang LIU
;
Ning LI
;
Junqin LEI
;
Silin CHEN
;
Jinming SHI
;
Huiying MA
;
Qiang ZENG
;
Yongwen SONG
;
Shulian WANG
;
Hua REN
;
Yueping LIU
;
Hui FANG
;
Ningning LU
;
Yu TANG
;
Shunan QI
;
Yong YANG
;
Bo CHEN
;
Yexiong LI
;
Jing JIN
Author Information
1. 国家癌症中心/国家肿瘤临床医学研究中心/中国医学科学院北京协和医学院肿瘤医院放疗科 100021
- Keywords:
Abdominal compression;
Gold marker;
Motion;
Liver neoplasm/stereotactic body radiation therapy
- From:
Chinese Journal of Radiation Oncology
2021;30(11):1142-1147
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the motion and influencing factors of implanted gold markers in guiding liver stereotactic body radiation therapy (SBRT) using abdominal compression.Methods:Twenty patients with oligometastatic colorectal cancer or primary hepatocellular carcinoma from January 2016 to December 2019 were included. All patients were treated with SBRT under abdominal compression, with 1-3 gold markers were implanted within 2 cm from the lesion before positioning. Four-dimensional computed tomography (4DCT) scan was used for treatment planning. The respiratory cycle was divided into 0-90% respiratory phase images based on the respiratory signal, which were reconstructed by the system (Pinnacle 3 version 9.1; Philips Medical System, Madison, WI, USA), and cone beam CT validation images before radiation exposure were obtained. The liver volume was divided into 3 parts: within 2 cm from the main hepatic portal vein, 2-5 cm from the main hepatic portal vein, and>5 cm from the main hepatic portal vein. The motion of different tumor locations was evaluated. Results:The average intrafractional motion amplitude was (2.63±2.81) mm in the cranial-caudal (CC) direction, (1.35±1.23) mm in the anterior-posterior (AP) direction, and (0.76±0.88) mm in the left-right (LR) direction, respectively. The average interfractional motion amplitude was (3.45±3.06) mm, (2.64±2.60) mm, and (2.23±2.07) mm, respectively. Both the intra-or inter-fractional motion amplitudes in the CC direction were the highest, followed by those in the AP and LR direction (all P<0.001). The motion varied at different tumor locations. The longer distance from the main hepatic portal vein, the larger the intrafractional motion (all P<0.05). To cover the 95% population-based confidence interval, the internal target volume (ITV) was suggested to include the expansion of 3.9 mm, 5.2 mm and 7.9 mm in the LR, AP and CC direction. The expansion of 4.3 mm, 4.4 mm and 6.1 mm was delivered within 2 cm from the main hepatic portal vein, and 3.5 mm, 7.3 mm and 9.7 mm>5 cm from the main hepatic portal vein, respectively. The expansion varied significantly depending on the tumor location, whereas the motion in the CC direction was the largest regardless of the tumor location. The longer distance of the tumor from the main portal vein, the larger expansion in the CC direction. The expansion of tumor > 5 cm from the main portal vein in the AP direction was larger than that of inner parts. Conclusion:Liver tumors at different locations require individual external expansion of ITV.
