The aim of this planning study was to compare the dosimetric outcomes of Volumetric Modulated Arc Therapy (VMAT), Proton Beam Therapy (PBT), and conventional External Beam Radiation Therapy (cEBRT) in the treatment of thoracic spinal metastases originating from breast or prostate cancer. Our study utilized data from 30 different treatment plans and evaluated target coverage and doses to vital organs at risk (OARs), such as the spinal cord, heart, esophagus, and lungs. The results showed that VMAT and PBT achieved superior target coverage and significantly lower doses to the spinal cord compared to cEBRT (target: median PTVD95%: 75.2 for cEBRT vs. 92.9 and 91.7 for VMAT (p< 0.001) and PBT (p< 0.001), respectively; spinal cord: median Dmax%: 105.1 for cEBRT vs. 100.4 and 103.6 for VMAT (p< 0.001) and PBT (p= 0.002), respectively). Specifically, VMAT was notable for its superior target coverage and PBT for significantly lower doses to heart, lungs, and esophagus. However, VMAT resulted in higher lung doses, indicating potential trade-offs among different techniques. The study demonstrated the relative advantages of VMAT and PBT over traditional RT in the palliative treatment of spinal metastases using conventional fractionation. These findings underscore the potential of VMAT and PBT to improve dosimetric outcomes, suggesting that they may be more suitable for certain patient groups for whom the sparing of specific OARs is especially important.
本研究旨在比较容积旋转调强放疗（VMAT）、质子束治疗（PBT）与传统外照射放疗（cEBRT）在治疗源于乳腺癌或前列腺癌的胸椎转移瘤中的剂量学结果。研究基于30例不同治疗计划的数据，评估了靶区覆盖情况及脊髓、心脏、食管和肺等重要危及器官的受照剂量。结果显示，与cEBRT相比，VMAT和PBT在靶区覆盖方面表现更优，且脊髓受照剂量显著降低（靶区：cEBRT的PTVD95%中位数为75.2，而VMAT和PBT分别为92.9（p<0.001）和91.7（p<0.001）；脊髓：cEBRT的Dmax%中位数为105.1，而VMAT和PBT分别为100.4（p<0.001）和103.6（p=0.002））。具体而言，VMAT在靶区覆盖方面表现突出，而PBT在降低心脏、肺和食管剂量方面具有显著优势。但VMAT会导致肺剂量升高，提示不同技术间存在权衡取舍。本研究证明了在常规分割模式下姑息治疗脊柱转移瘤时，VMAT和PBT相较于传统放疗具有相对优势。这些发现强调了VMAT和PBT在改善剂量学结果方面的潜力，表明对于特定危及器官保护尤为重要的患者群体，这两种技术可能更为适用。
肿瘤(癌症)患者之家