Jung Sang Hoon, Kim Jinsung, Chung Yoonsun, Keserci Bilgin, Pyo Hongryull, Park Hee Chul, Park Won
Department of Radiation Oncology, Samsung Medical Center, Seoul, Korea.
Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Korea.
Radiat Oncol J. 2020 Mar;38(1):52-59. doi: 10.3857/roj.2020.00101. Epub 2020 Mar 27.
To evaluate and compare the feasibilities of magnetic resonance (MR) image-based planning using synthetic computed tomography (sCT) versus CT (pCT)-based planning in helical tomotherapy for prostate cancer.
A retrospective evaluation was performed in 16 patients with prostate cancer who had been treated with helical tomotherapy. MR images were acquired using a dedicated therapy sequence; sCT images were generated using magnetic resonance for calculating attenuation (MRCAT). The three-dimensional dose distribution according to sCT was recalculated using a previously optimized plan and was compared with the doses calculated using pCT.
The mean planning target volume doses calculated by sCT and pCT differed by 0.65% ± 1.11% (p = 0.03). Three-dimensional gamma analysis at a 2%/2 mm dose difference/distance to agreement yielded a pass rate of 0.976 (range, 0.658 to 0.986).
The dose distribution results obtained using tomotherapy from MR-only simulations were in good agreement with the dose distribution results from simulation CT, with mean dose differences of less than 1% for target volume and normal organs in patients with prostate cancer.
评估并比较在螺旋断层放射治疗前列腺癌中，基于合成计算机断层扫描（sCT）的磁共振（MR）图像规划与基于CT（pCT）的规划的可行性。
对16例接受螺旋断层放射治疗的前列腺癌患者进行回顾性评估。使用专用治疗序列采集MR图像；使用磁共振计算衰减（MRCAT）生成sCT图像。使用先前优化的计划重新计算根据sCT的三维剂量分布，并与使用pCT计算的剂量进行比较。
sCT和pCT计算的平均计划靶体积剂量相差0.65%±1.11%（p = 0.03）。在2%/2 mm剂量差异/一致距离下的三维伽马分析通过率为0.976（范围为0.658至0.986）。
在前列腺癌患者中，仅使用MR模拟的断层放射治疗获得的剂量分布结果与模拟CT的剂量分布结果高度一致，靶体积和正常器官的平均剂量差异小于1%。
