Application value of low-dose 4DCT scanning in simulation and target delineation for solitary pulmonary tumors
10.3760/cma.j.cn113030-20210122-00037
- VernacularTitle:低剂量4DCT扫描在肺内孤立性肿瘤模拟定位与靶区构建中的应用价值
- Author:
Dongping SHANG
1
;
Lijuan LUAN
;
Lizhen WANG
;
Qingning SUN
;
Jinming YU
;
Yong YIN
Author Information
1. 山东省肿瘤防治研究院(山东省肿瘤医院)放疗科，山东第一医科大学(山东省医学科学院), 济南 250117
- Keywords:
Low dose;
Tomography, X-ray computed, four-dimensional;
Gross tumor volume;
Lung neoplasm/radiotherapy
- From:
Chinese Journal of Radiation Oncology
2022;31(2):165-169
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the feasibility of low-dose 4DCT scanning in simulation and target delineation for solitary pulmonary tumors (SPTs).Methods:23 patients with SPTs received 4DCT scanning simulation with the conventional scanning (CON), low voltage (LV), low current (LA) and low voltage combined with low current (LVA) in sequence. Based on the 4DCT images derived from the four sets of scanning parameters, the internal gross tumor volume (IGTV CON, IGTV V, IGTV A, IGTV VA) of SPTs were delineated and matched. Taking IGTV CON as reference, the tumor displacement and the centroid position of IGTV V, IGTV A and IGTV VA were compared with IGTV CON. The radiation doses under different scanning parameters were compared. Results:The volumes of IGTV CON, IGTV V and IGTV A were (12.26±12.30) cm 3, (12.21±12.16) cm 3 and (11.87±11.70) cm 3, respectively ( P=0.337). IGTV VA was (11.34±11.07) cm 3, significantly smaller than IGTV CON ( P=0.005). There was no significant difference in the centroid positions of IGTV CON, IGTV V, IGTV A and IGTV VA in three directions ( P=0.491, 0.360, 0.136). The Dice′s similarity coefficient (DSC VA) was significantly lower than DSC V and DSC A ( P=0.004, 0.030). The tumor displacement measured by the four sets of 4DCT images was similar in the LR direction ( P=0.470), and also in the AP direction ( P=0.108). For the displacement in the SI direction, LVA scanning was smaller than CON ( P=0.015). The radiation doses under four different scanning conditions were (397.0±140.3) mGy·cm, (175.0±61.8) mGy·cm, (264.8±95.3) mGy·cm and (116.8±41.2) mGy·cm, respectively ( P<0.001). Conclusions:LV or LA scanning exert no significant effect on the volume, centroid position of IGTV and the tumor displacement in 4DCT simulation for SPTs. The radiation dose that patients receive under LV and LV scanning is lower than that of CON. Consequently, LV or LA scanning is feasible in 4DCT simulation and target delineation for SPTs.
