Pielkenrood Bart J, Visser Thomas F, van Tol Floris R, Foppen Wouter, Eppinga Wietse S C, Verhoeff Joost J C, Bol Gijs H, Van der Velden Joanne M, Verlaan Jorrit-Jan
Department of Radiation Oncology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
Department of Radiation Oncology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands.
Spine J. 2023 Apr;23(4):571-578. doi: 10.1016/j.spinee.2022.12.018. Epub 2023 Jan 6.
Palliative radiotherapy (RT) can lead to remineralization of osteolytic lesions thereby potentially restoring some of the weight-bearing capacity and preventing vertebral collapse. It is not clear, however, under which circumstances remineralization of osteolytic lesions occurs.
The aim of this study was to investigate the change in bone mineral density in spinal metastases after RT compared to a reference region, and find associated factors.
Retrospective analysis within prospective observational cohort OUTCOME MEASURES: change in bone mineral density measured in Hounsfield Units (HU).
patients treated with RT for (painful) bone metastases.
Patients with spinal metastases were included if computed tomography scans both pre- and post-RT were available. Bone density was measured in HU. A region of interest (ROI) was drawn manually in the metastatic lesion. As a reference, a measurement of bone density in adjacent, unaffected, and non-irradiated vertebrae was used. Factors tested for association were origin of the primary tumor, RT dose and fractionation scheme, and concomitant use of bisphosphonates.
A total of 31 patients with 49 spinal metastases, originating from various primary tumors, were included. The median age on baseline was 58 years (IQR: 53-63) and median time between baseline and follow-up scan was 8.2 months (IQR: 3.0-18.4). Difference in HU in the lesion before and after treatment was 146.9 HU (95% CI 68.4-225.4; p<.01). Difference in HU in the reference vertebra between baseline and first follow-up was 19.1 HU (95% CI -47.9 to 86.0; p=.58). Difference between reference vertebrae and metastatic lesions on baseline was -194.1 HU (95% CI -276.2 to -112.0; p<.01). After RT, this difference was reduced to -50.3 HU (95% CI -199.6 to 99.0; p=.52). Patients using bisphosphonates showed a greater increase in HU, 194.1 HU versus 60.6 HU, p=.01.
Palliative radiation of osteolytic lytic spinal metastases is positively associated with an increased bone mineral density at follow-up. The use of bisphosphonates was linked to an increased bone mineral density when used during or after RT.
姑息性放疗（RT）可导致溶骨性病变再矿化，从而有可能恢复部分承重能力并防止椎体塌陷。然而，尚不清楚溶骨性病变在何种情况下会发生再矿化。
本研究的目的是调查与参考区域相比，放疗后脊柱转移瘤骨密度的变化，并找出相关因素。
前瞻性观察队列中的回顾性分析
以亨氏单位（HU）测量的骨密度变化
接受放疗治疗（疼痛性）骨转移的患者
如果有放疗前后的计算机断层扫描，则纳入脊柱转移瘤患者。骨密度以HU测量。在转移瘤病变处手动绘制感兴趣区域（ROI）。作为对照，使用相邻、未受影响且未接受照射的椎体的骨密度测量值。测试相关性的因素包括原发肿瘤的起源、放疗剂量和分割方案以及双膦酸盐的联合使用。
共纳入31例患者的49处脊柱转移瘤，原发肿瘤各不相同。基线时的中位年龄为58岁（四分位间距：53 - 63岁），基线与随访扫描之间的中位时间为8.2个月（四分位间距：3.0 - 18.4个月）。治疗前后病变处的HU差值为146.9 HU（95%置信区间68.4 - 225.4；p <.01）。基线与首次随访时对照椎体的HU差值为19.1 HU（95%置信区间 - 47.9至86.0；p = 0.58）。基线时对照椎体与转移瘤病变处的差值为 - 194.1 HU（95%置信区间 - 276.2至 - 112.0；p <.01）。放疗后，该差值降至 - 50.3 HU（95%置信区间 - 199.6至99.0；p = 0.52）。使用双膦酸盐的患者HU增加幅度更大，分别为194.1 HU和60.6 HU，p = 0.01。
溶骨性脊柱转移瘤的姑息性放疗与随访时骨密度增加呈正相关。在放疗期间或放疗后使用双膦酸盐与骨密度增加有关。
