Study on AlignRT guided set-up of breast-conserving radiotherapy and the impact of patients′ thoracic characteristic parameters
10.3760/cma.j.cn112271-20240424-00153
- VernacularTitle:AlignRT引导下保乳术后乳腺癌放疗摆位及患者胸廓特征参数影响研究
- Author:
Ailin WU
1
;
Lin YAN
1
;
Xinglei WU
1
;
Peng ZHANG
1
;
Jingjing CHENG
1
;
Chunbao ZANG
1
;
Hongbo ZHANG
1
;
Aidong WU
1
Author Information
1. 中国科学技术大学附属第一医院西区放疗科，合肥 230031
- Publication Type:Journal Article
- Keywords:
Breast cancer;
Breast-conserving radiotherapy;
Surface-guided radiation therapy;
Set-up error;
Thoracic characteristic parameters
- From:
Chinese Journal of Radiological Medicine and Protection
2025;45(1):24-30
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To compare the impact of the AlignRT-based optical guidance method with the traditional marker line method on the accuracy of positioning, and explore the effect of patient′s different thoracic characteristic parameters on the precision of optical guidance positioning.Methods:A total of sixty breast cancer patients who received post breast-conserving radiotherapy at Anhui Cancer Hospital from July 2022 to September 2023 were retrospectively selected. Then these patients were equally divided into traditional cross hairs set-up (marker line group) and surface-guided set-up (SGRT group). The cone-beam CT scanning results were used as the gold standard, the three-dimensional set-up errors and the CTV-PTV target area external radiotherapy boundaries of two groups were studied comparatively. Multiple patient′s thoracic characteristic parameters were defined and the correction between each parameter and set-up error of SGRT was analyzed.Results:The mean value of three-dimensional set-up errors in the SGRT group and the marker line group was within 0.2 cm and 0.5 cm, respectively. The differences in three-dimensional set-up errors and total displacements between two groups were statistically significant ( z=-2.93, -3.21, -2.59, -4.76, P<0.05). The SGRT group reduced the CTV-PTV boundary from 0.5 cm of conventional marker line group to 0.3 cm. The thoracic aspect ratio H/W, the affected side pinch angle α1, and the healthy side pinch angle α2 were positively correlated with the x-direction posing error ( r=0.49, 0.59, 0.71, P<0.05); whereas, the affected side and the healthy side mammary gland heights D1 and D2 were negatively correlated with the z-direction posing error ( r=-0.46, -0.49, P<0.05). Conclusions:For breast-conserving postoperative radiotherapy patients, SGRT can obtain a more accurate radiotherapy set-up than the traditional marker line method, and can effectively reduce the target area externally expanded range. Meanwhile, the monitoring accuracy of SGRT is affected by the patient′s thoracic characteristic parameters, and clinical attention should be paid to breast-conserving radiotherapy patients with thick body shape, narrow body width, and small breast glands.
