CT灌注成像对骨巨细胞瘤潜恶性的识别

目的通过临床骨巨细胞瘤的检查，分析各CT灌注参数、最大强化速率（MER）与肿瘤的微血管密度（MVD）的关系；探讨MER在骨巨细胞瘤诊断中的应用价值；评价边缘-中心血流量差异率（Rrim-cen BF）、边缘-中心血容量差异率（Rrim-cen BV）在良恶性骨巨细胞瘤鉴别诊断中的应用价值。方法对24例病人的骨巨细胞瘤行CT灌注检查，其中恶性骨巨细胞瘤14例，良性骨巨细胞瘤10例。术后病理标本常规组织切片及SP免疫组织化学检查，单克隆抗CD34抗体标记血管，用Weidner技术计算肿瘤MVD。分析BF、BV、MER与肿瘤微血管密度的相关性；分析良恶性骨巨细胞瘤外周区与中央区之间BF、BV有无差异；比较良恶性骨肿瘤之间MER、Rrim-cen BF、Rrim-cen BV的差异。结果24例骨巨细胞瘤均表现为高灌注，BF和BV图像上均可清楚显示肿瘤；骨巨细胞瘤的BF、BV和MER与MVD均呈正线性相关。MER能够准确地反映组织的血管化程度，但MER在良恶性骨巨细胞瘤之间存在较多重叠。Rrim-cen BF和Rrim-cen BV值在良恶性骨巨细胞瘤之间的差异具有最著性意义（P〈0．01）。Rrim-cen BF和Rrim-cen BV鉴别良恶性骨肿瘤的阈值分别为Rrim-cen BF：0．15（敏感度：94．4％；特异度：85．7％）；Rrim-cen BV：0．07（敏感度：88．9％；特异度：78．5％）。结论MER可以客观定量地评估骨巨细胞瘤的血供情况，但不能单独应用作为鉴别良恶性骨巨细胞瘤的指标。Rrim-cen BF和Rrim-cen BV为骨巨细胞瘤良恶性鉴别提供了一种有价值的客观定量的影像学检测指标。

The potential malignance of giant cell tumor of bone: differentiation with CT perfusion

Objective For the clinical CT examination of the patients with giant cell tumor of bone: to analyse the relationship between the CT perfusion parameters, the maximal enhancement rate (MER) and the microvessel density (MVD) of the tumors; to investigate the diagnostic value of MER in giant cell tumor of bone; to assess diagnostic value of rim-to-center differential blood flow ratio (R_rim-cenBF) and rim-to-center differential blood volume ratio (R_rim-cenBV) in differentiating benign from malignant giant cell tumor of bone. Methods Twenty-four patients with a giant cell tumor of bone were examined with CT perfusion imaging . Of the 24 patients, 14 were malignant and 10 were benign. Twenty-four giant cell tumors of bone histologically confirmed were underwent SP immunohistochemistry staining. The anti-CD34 monoclonal antibodies were used to mark the microvessels. The MVD of the tumors were calculated using Weidner technique. The differences between BF and BV in the rim and center of benign and malignant giant cell tumor of bone were analysed. The correlations between MER,BF,BV and MVD of the tumors were analysed. The MER,R_rim-cenBF and R_rim-cenBV of benign and malignant lesions were compared. Results Twenty-four giant cell tumors of bone demonstrated high perfusion with well-defined the contour on the BF and BV mapping imaging. There was positive linear correlation between the tumor MVD and tumor BF, BV and MER. MER reflected the vascularity of tissue accurately, but existed overlap between benign and malignant giant cell tumor of bone. The R_rim-cenBF and R_rim-cenBV of benign and malignant bone tumors differed significantly (P<0.01). When a cutoff value was 0.15 for R_rim-cenBF and 0.07 for R_rim-cenBV, the sensitivity was 94.4 and 88.9%, and the specificity was 85.7% and 78.5% respectively. Conclusion The MER reflected the amount of vascularity of giant cell tumor of bone accurately and estimated the degree of blood supply objectively. Howerer it can't be used as a parameter to distinguish benign from malignant. The R_rim-cenBF and R_rim-cenBV can be used as parameters to differentiate malignant giant cell tumor of bone from benign ones, which is on the basis of theory that the pattern of vascularity in benign and malignant tumors is fundamentally different. The R_rim-cenBF and R_rim-cenBV provide a diagnostically useful quantitative indicator to evaluate giant cell tumor of bone.