Setup errors using four-dimensional cone-beam computed tomography and their influence on target dose-volume parameters in lung cancer patients treated with stereotactic body radiotherapy
10.13491/j.issn.1004-714X.2026.02.007
- VernacularTitle:四维锥形束CT对肺癌立体定向放疗患者摆位误差及其对靶区受量影响
- Author:
Yiming XUE
1
;
Jinrong WANG
1
;
Ya LI
1
Author Information
1. Department of Radiotherapy, East China Hospital, Fudan University, Shanghai 200040, China.
- Publication Type:OriginalArticles
- Keywords:
Four-dimensional cone-beam computed tomography;
Lung cancer;
Stereotactic body radiotherapy;
Setup error;
Radiation exposure
- From:
Chinese Journal of Radiological Health
2026;35(2):200-205
- CountryChina
- Language:Chinese
-
Abstract:
Objective This study aims to assess the impact of four-dimensional cone-beam computed tomography (4D-CBCT) image guidance on setup error correction and target dose distribution optimization in patients receiving stereotactic body radiotherapy for lung cancer. Methods A total of 82 lung cancer patients treated with SBRT in our hospital between February 2023 and February 2025 were randomly selected as study subjects. Using a random number table, they were divided into two groups. The conventional group underwent positioning verification using traditional three-dimensional cone-beam CT, while the study group underwent verification using 4D-CBCT. Setup errors, target dose-volume parameters, organ at risk dose-volume parameters, and adverse reactions were compared between the two groups. Results The setup errors in the X, Y, and Z axes in the study group were 0.21, 0.19, and 0.23 mm, respectively, which were significantly lower than 0.58, 0.62, and 0.59 mm in the conventional group (P<0.05). The three-dimensional vector error was 0.34 (0.21, 0.48) mm in the study group, which was significantly lower than 0.98 (0.65, 1.32) mm in the conventional group (P<0.05). The rotational errors in left-right, anteroposterior, and superior-inferior directions in the study group were (0.25±0.12)°, (0.21±0.10)°, and (0.23±0.11)°, respectively; these values were significantly lower than (0.48±0.18)°, (0.42±0.15)°, and (0.45±0.16)° in the conventional group (P<0.05). The minimum dose received by 95% of the target volume [(59.45±0.85) Gy] and the percentage of the target volume receiving at least 100% of the prescription dose [(95.82±2.65)%] in the study group were higher than those in the conventional group [(58.90±1.20) Gy and (93.65±3.85)%]. The homogeneity index and conformity index in the study group were 1.07±0.03 and 1.15±0.05, respectively, which were lower than 1.12±0.05 and 1.23±0.08 in the conventional group (P<0.05). No significant differences were observed between the two groups in the volume of the lung receiving 5 Gy [(28.11±5.52)% vs. (28.85±6.24)%], the volume of the lung receiving 20 Gy [(12.84±3.56)% vs. (13.45±3.90)%], mean lung dose [(8.65±2.11) Gy vs. (8.95±2.34) Gy], maximum spinal cord dose [(18.54±3.62) Gy vs. (19.13±4.25) Gy], or mean heart dose[(14.85±4.22) Gy vs. (16.27±4.83) Gy](P>0.05). The incidence rates of radiation pneumonitis, radiation esophagitis, and skin reactions in the study group were 12.20%, 7.32%, and 4.88%, respectively, which were not significantly different from 17.07%, 9.76%, and 7.32% in the conventional group (P>0.05). Conclusion The 4D-CBCT can reduce setup errors, improve target dose accuracy and conformity in lung cancer patients undergoing SBRT, and minimize radiation exposure to normal tissues, making it worthy of clinical promotion.