Chai Hongbo, Miyasaka Yuya, Hagiwara Yasuhito, Souda Hikaru, Ishizawa Miyu, Sato Hiraku, Iwai Takeo
Department of Heavy Particle Medical Science, Yamagata University Graduate School of Medical Science, Yamagata, Japan.
Department of Radiology, Yamagata University Faculty of Medicine, Yamagata, Japan.
Prostate. 2025 Feb;85(2):123-129. doi: 10.1002/pros.24808. Epub 2024 Oct 8.
The uncertainty of target location during prostate cancer radiotherapy plays an important role in accurate dose delivery and radiation toxicity in adjacent organs. This study analyzed displacement correlations between the prostate and pelvic floor.
We retrospectively analyzed registration results from 467 daily cone-beam computed tomography (CT) in 12 patients with prostate cancer who received radiation therapy. We analyzed prostate displacement and the pelvic floor relative to the pelvic bone's anatomy in the translational and rotational directions and identified statistical correlations.
The systematic (Σ) and random (σ) displacements of the prostate in the three translational directions, anterior-posterior (AP), superior-inferior (SI), and right-left (RL), were 1.49 ± 1.45, 2.10 ± 1.40, and 0.24 ± 0.53 mm, respectively, and in the rotational directions of the pitch, roll, and yaw were 2.10 ± 2.02°, 0.42 ± 0.74°, and 0.42 ± 0.64°, respectively. The pelvic floor displacements were 2.37 ± 1.96, 2.71 ± 2.28, and 0.47 ± 0.84 mm in the AP, SI, and RL directions, respectively, and 0.93 ± 1.49°, 0.98 ± 1.28 °, and 0.87 ± 0.94° in the pitch, roll, and yaw directions, respectively. Additionally, there were statistically significant correlations between the displacement of the prostate and pelvic floor in the AP and SI directions, with correlation coefficients (r) of 0.74 (p < 0.001) and 0.69 (p < 0.001), respectively.
The movement of the pelvic floor may be an important factor that causes prostate displacement, affecting the accuracy of radiotherapy. Therefore, it is necessary to take appropriate measures to ensure that the pelvic floor muscle tension is as consistent as possible in the treatment' CT scan and daily treatment.
前列腺癌放疗期间靶区位置的不确定性在精确剂量输送和邻近器官的放射毒性方面起着重要作用。本研究分析了前列腺与盆底之间的位移相关性。
我们回顾性分析了12例接受放射治疗的前列腺癌患者467次每日锥形束计算机断层扫描（CT）的配准结果。我们分析了前列腺相对于骨盆骨解剖结构在平移和旋转方向上的位移，并确定了统计相关性。
前列腺在前后（AP）、上下（SI）和左右（RL）三个平移方向上的系统（Σ）和随机（σ）位移分别为1.49±1.45、2.10±1.40和0.24±0.53毫米，在俯仰、横滚和偏航的旋转方向上分别为2.10±2.02°、0.42±0.74°和0.42±0.64°。盆底在AP、SI和RL方向上的位移分别为2.37±1.96、2.71±2.28和0.47±0.84毫米，在俯仰、横滚和偏航方向上分别为0.93±1.49°、0.98±1.28°和0.87±0.94°。此外，前列腺和盆底在AP和SI方向上的位移之间存在统计学显著相关性，相关系数（r）分别为0.74（p<0.001）和0.69（p<0.001）。
盆底运动可能是导致前列腺位移的一个重要因素，影响放疗的准确性。因此，有必要采取适当措施确保在治疗的CT扫描和日常治疗中盆底肌肉张力尽可能一致。
