26481Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, The Affiliated Cancer Hospital of Nanjing Medical University, Nanjing, China.
Technol Cancer Res Treat. 2022 Jan-Dec;21:15330338221074501. doi: 10.1177/15330338221074501.
To evaluate if the Halcyon(2.0) Intensity Modulation Radiotherapy (IMRT) technique has an advantage in the long-course rectal cancer radiotherapy. A total of 20 clinical IMRT plans of Halcyon(2.0) for long-course (2Gy in 25 fractions) rectal cancer radiotherapy were randomly selected. Based on the parameters of these plans, 20 TrueBeam (with the Millennium 120 MLC) plans were redesigned, respectively. The dosimetry indexes, field complexity parameters, the Gamma Passing Rates (GPR), and the delivery time of the 2 groups of plans were obtained as measures of the plan quality, the modulation complexity, the delivery accuracy, and the delivery efficiency. The differences between the 2 groups of parameters were analyzed, with < .05 means statistically significant. In terms of dosimetry, there was no significant or clinical difference between the 2 groups in critical dosimetry parameters. The Monitor Unit of the Halcyon(2.0) fields is lower than the TrueBeam fields by 26.39, while the modulation complexity score (MCS), the mean aperture area variability (AAV), and the mean leaf sequence variability (LSV) of the Halcyon(2.0) fields were 23.8%, 20%, and 2.3% larger than those of the TrueBeam fields, respectively. Neither the ArcCheck-based GPRs nor the portal-dosimetry-based GPRs in both 3%/3 mm and 2%/2 mm criteria showed the difference between the Halcyon(2.0) fields and the TrueBeam fields. The Pearson correlation coefficient between GPR(2%/2 mm) and MCS of the Halcyon(2.0) fields was 0.335, while that of the TrueBeam fields was 0.502. The mean total delivery time of the TrueBeam plans was 195.55 ± 22.86 s, while that of Halcyon(2.0) was 124.25 ± 10.42 s ( < .001), which was reduced approximatively by 36%. For long-course rectal cancer radiotherapy, the Halcyon(2.0) IMRT plans behave almost the same in dosimetry and delivery accuracy as the TrueBeam plans. However, the lower MU and the field modulation complexity, combined with the higher delivery efficiency, make Halcyon(2.0) a feasible and reliable platform in long-course radiotherapy for the rectal cancer.
为了评估 Halcyon(2.0) 强度调制放疗 (IMRT) 技术在长程直肠癌放疗中的优势，我们随机选择了 20 例 Halcyon(2.0) 用于长程 (2Gy 分 25 次) 直肠癌放疗的临床 IMRT 计划。基于这些计划的参数，我们分别重新设计了 20 例 TrueBeam(配备 Millennium 120 MLC)计划。作为计划质量、调制复杂性、输送准确性和输送效率的衡量标准，获得了两组计划的剂量学指标、野复杂度参数、伽马通过率 (GPR) 和输送时间。分析了两组参数之间的差异， < .05 表示具有统计学意义。 在剂量学方面，两组在关键剂量学参数方面没有显著差异或临床差异。Halcyon(2.0) 野的监测器单位比 TrueBeam 野低 26.39，而 Halcyon(2.0) 野的调制复杂度评分 (MCS)、平均孔径面积变异性 (AAV) 和平均叶片序列变异性 (LSV) 分别比 TrueBeam 野大 23.8%、20%和 2.3%。ArcCheck 为基础的 GPR 和基于门户剂量学的 GPR 在 3%/3mm 和 2%/2mm 标准中均未显示出 Halcyon(2.0) 野与 TrueBeam 野之间的差异。Halcyon(2.0) 野的 GPR(2%/2mm)与 MCS 的 Pearson 相关系数为 0.335，而 TrueBeam 野的相关系数为 0.502。TrueBeam 计划的总输送时间平均值为 195.55 ± 22.86 s，而 Halcyon(2.0) 的输送时间平均值为 124.25 ± 10.42 s ( < .001)，减少了约 36%。 对于长程直肠癌放疗，Halcyon(2.0) IMRT 计划在剂量学和输送准确性方面与 TrueBeam 计划几乎相同。然而，较低的 MU 和野调制复杂性，结合更高的输送效率，使 Halcyon(2.0) 成为直肠癌长程放疗中一种可行和可靠的平台。
