Catalyst系统在乳腺癌患者放疗摆位应用及影响因素分析

目的 评价Catalyst系统在乳腺癌患者放疗摆位中的应用,并分析其与患者年龄及BMI的相关性。方法 选取 2016年5-8月间重庆市肿瘤研究所收治的 24例乳腺癌患者。每次治疗前均采用表面光学成像系统(C-Rad Catalyst)辅助摆位,每周1次kV-kV位置验证模式验证摆位。记录并观察患者的年龄、BMI以及2个系统在三维方向摆位误差。采用独立样本t检验差异,采用Pearson相关性分析。结果 C-Rad Catalyst系统与kV-kV位置验证模式的摆位误差分别为AP方向(0.22±0.17) cm与(0.18±0.13) cm (P<0.05);SI方向(0.23±0.18) cm与(0.19±0.15) cm (P>0.05);LR方向(0.28±0.28) cm与(0.20±0.15) cm (P>0.05)。kV-kV位置验证模式摆位受年龄和BMI的影响不显著(P均>0.05);而C-Rad Catalyst系统的摆位受年龄和BMI影响显著:年龄≤44岁和 45~59岁患者在AP、SI方向不同(P均<0.05),≤44岁和≥60岁患者在AP、LR方向不同(P均<0.05),45~59岁和≥60岁患者在LR方向不同(P<0.05);BMI<25 kg/m²和≥25 kg/m²患者在SI方向不同(P<0.05)。年龄≥60岁患者C-Rad Catalyst系统摆位误差在SI方向与年龄相关(r=-0.496,P<0.05);BMI<25 kg/m²患者C-Rad Catalyst系统摆位误差在AP方向与BMI相关(r=0.252,P<0.05),而BMI≥25 kg/m²患者C-Rad Catalyst系统摆位误差在SI方向与BMI相关(r=0.445,P<0.05)。结论 C-Rad Catalyst系统摆位与kV-kV位置验证模式在AP方向上差异显著,C-Rad Catalyst系统摆位易受乳腺癌患者年龄和BMI的影响。

Catalyst system in patient positioning during breast cancer radiotherapy:clinical application and influencing factors

Objective To evaluate the clinical application of Catalyst system in patient positioning during breast cancer radiotherapy, and to analyze its correlation with age and body mass index (BMI). Methods Twenty-four patients with breast cancer who were admitted to our hospital from May to August, 2016 were enrolled as subjects. For all patients, auxiliary positioning was made by the optical surface imaging system (C-Rad Catalyst) before each treatment. The kV-kV imaging was executed weekly to verify positioning. Age, BMI, and setup errors of the two systems in the anterior-posterior (AP), superior-inferior (SI), and left-right (LR) directions were recorded and analyzed by independent samples t-test and Pearson correlation analysis. Results The C-Rad Catalyst system had a significantly larger setup error in the AP direction than the kV-kV imaging (0.22±0.17 vs. 0.18±0.13 cm, P<0.05). There were no significant differences in setup errors in the SI or LR direction between the two systems (0.23±0.18 vs. 0.19±0.15 cm, P>0.05;0.28±0.28 vs. 0.20±0.15 cm, P>0.05). Age and BMI of patients had significant impacts on the C-Rad Catalyst system but the kV-kV imaging (P>0.05):there were significant differences in setup errors in the AP and SI directions between patients ≤44 years of age and those 45-59 years of age (all P<0.05);there were significant differences in setup errors in the AP and LR directions between patients ≤44 years of age and those ≥60 years of age (all P<0.05);there was a significant difference in setup error in the LR direction between patients 45-59 years of age and those ≥60 years of age (P<0.05);there was a significant difference in setup error in the SI direction between patients with BMIs of<25 and ≥25 kg/m²(P<0.05). For patients ≥60 years of age, setup error of the C-Rad Catalyst system in the SI direction was correlated with age (r=-0.496, P<0.05). For patients with BMI of<25 kg/m², setup error of the C-Rad Catalyst system in the AP direction was correlated with BMI (r=-0.445,P<0.05). For patients with a BMI of ≥25 kg/m², setup error of the C-Rad Catalyst system in the SI direction was correlated with BMI (r=-0.252,P<0.05). Conclusions There is significant difference in setup error in the AP direction between the C-Rad Catalyst system and the kV-kV imaging. Age and BMI have impacts on patient positioning by the C-Rad Catalyst system.