OBJECTIVE: To evaluate the performance of an offline geometric correction strategy in ensuring accuracy and reproducibility during radiotherapy delivery in Wilm\'s tumor patients.
METHODS: The extended no-action level offline correction strategy was applied in the radiotherapy delivery of 45 Wilm\'s tumor patients. Gross errors from the first three fractions were used to calculate the mean errors which were then applied as offline correction factors. Mean errors among different groups were compared using a two-way analysis of variance (ANOVA) and Dunnett\'s pairwise comparisons. All statistical analyses and data visualization were performed using GraphPad Prism version 7 (Insight Partners, GraphPad Holdings, LLC).
RESULTS: A total of 45 patients were included in the study. In all three orthogonal directions, the recorded gross errors were significantly lower after the application of the systematic error corrections. Random errors were significantly larger in the longitudinal direction compared to lateral (mean difference = 0.28, p = 0.036) and vertical directions (mean difference = 0.37 cm, p = 0.003). Patients\' age was a significant predictor of random errors whereby the magnitude of random error decreased with increasing age.
CONCLUSIONS: This study shows that the offline correction strategy used is effective in ensuring the accuracy of radiotherapy delivery in pediatric Wilm\'s tumor patients.
目的:评估离线几何校正策略在确保Wilm\'s肿瘤患者放疗期间的准确性和可重复性方面的性能。
方法:在45例Wilm\'s肿瘤患者的放疗中应用了扩展无作用水平离线矫正策略。来自前三个部分的粗差用于计算平均误差,然后将其用作离线校正因子。使用双向方差分析(ANOVA)和Dunnett的成对比较来比较不同组之间的平均误差。所有统计分析和数据可视化均使用GraphPadPrism版本7(InsightPartners,GraphPad控股公司,LLC).
结果:共45例患者纳入研究。在所有三个正交方向上,应用系统误差校正后,记录的粗差显著降低。与横向(平均差=0.28,p=0.036)和垂直方向(平均差=0.37cm,p=0.003)。患者年龄是随机误差的重要预测指标,随机误差的大小随着年龄的增长而降低。
结论:这项研究表明,所使用的离线矫正策略可有效确保小儿Wilm's肿瘤患者放疗的准确性。