Tamada Tsutomu, Sone Teruki, Jo Yoshimasa, Imai Shigeki, Kajihara Yasumasa, Fukunaga Masao
Department of Radiology, Kawasaki Medical School, 577 Matsushima, 701-0192 Kurashiki, Okayama , Japan.
Skeletal Radiol. 2005 Mar;34(3):149-55. doi: 10.1007/s00256-004-0855-x. Epub 2004 Nov 16.
Prostate cancer frequently metastasizes to bone, inducing osteosclerotic lesions. The objective of this study was to clarify the three-dimensional (3D) trabecular bone microstructure in bone metastasis from prostate cancer by comparison with normal and degenerative sclerotic bone lesions, using microcomputed tomography (micro-CT).
A total of 32 cancellous bone samples were excised from the lumbar spine of six autopsy patients: 15 metastatic samples (one patient), eight degenerative sclerotic samples (four patients) and the rest from normal sites (three patients). The samples were serially scanned cross-sectionally by micro-CT with a pixel size of 23.20 microm, slice thickness of 18.56 microm, and image matrix of 512 x 512. Each image data set consisted of 250 consecutive slices. The volumes of interest (96 x 96 x 120 voxels) were defined in the original image sets and 3D indices of the trabecular microstructure were determined.
The trabecular thickness (Tb.Th) in degenerative sclerotic lesions was significantly higher than that in normal sites, whereas no significant difference was observed in trabecular number (Tb.N). By contrast, in metastatic lesions, the Tb.N was significantly higher with increased bone volume fraction (BV/TV) than in normal sites, and no significant difference was found in Tb.Th. The characteristics of the trabecular surface in the metastatic samples showed concave structural elements with an increase in BV/TV, indicating osteolysis of the trabecular bone. In 3D reconstructed images, increased trabecular bone with an irregular surface was observed in samples from metastatic sites, which were uniformly sclerotic on soft X-ray radiographs.
These results support, through 3D morphological features, the strong bone resorption effect in bone metastasis from prostate cancer.
前列腺癌常转移至骨骼，引发骨硬化性病变。本研究的目的是通过使用微型计算机断层扫描（micro-CT），将前列腺癌骨转移灶的三维（3D）小梁骨微观结构与正常和退行性硬化性骨病变进行比较，以阐明其特征。
从6例尸检患者的腰椎切除了共32个松质骨样本：15个转移样本（1例患者）、8个退行性硬化样本（4例患者），其余来自正常部位（3例患者）。样本通过micro-CT进行横断面连续扫描，像素大小为23.20微米，切片厚度为18.56微米，图像矩阵为512×512。每个图像数据集由250个连续切片组成。在原始图像集中定义感兴趣体积（96×96×120体素），并确定小梁微观结构的3D指标。
退行性硬化性病变中的小梁厚度（Tb.Th）显著高于正常部位，而小梁数量（Tb.N）无显著差异。相比之下,在转移病变中，与正常部位相比，骨体积分数（BV/TV）增加时Tb.N显著更高，而Tb.Th无显著差异。转移样本中小梁表面的特征显示，随着BV/TV增加，结构元素呈凹形，表明小梁骨发生骨溶解。在3D重建图像中，转移部位样本中观察到小梁骨增加且表面不规则，这些样本在软X线平片上均表现为硬化。
这些结果通过3D形态学特征支持前列腺癌骨转移中强烈的骨吸收效应。
