Correlation of In Vivo and In Vitro Measures of Carbonic Anhydrase IX Antigen Expression in Renal Masses Using Antibody 124I-cG250
Correlation of In Vivo and In Vitro Measures of Carbonic Anhydrase IX Antigen Expression in Renal Masses Using Antibody 124I-cG250
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DOI：
10.2967/jnumed.110.083295
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发表时间：
2011-04-01
影响因子：
9.3
通讯作者：
Divgi, Chaitanya R.
中科院分区：
文献类型：
--
作者：
Pryma, Daniel A.;O'Donoghue, Joseph A.;Divgi, Chaitanya R.
本研究的目的是确定在体内使用PET/CT和体外使用放射自显影和肿瘤组织伽马计数测定的肿瘤中放射标记大分子摄取的定量之间是否存在潜在的相关性。方法：26例计划手术切除的肾肿块患者接受i -124标记抗体cG250治疗。对切除后的肿瘤标本进行了研究。这些患者中有15例通过PET/CT图像和组织病理学阳性发现为透明细胞癌。在PET/CT图像上测量肿瘤的放射性，并以每克注射剂量百分比表示。然后将这些值归一化到PET/CT时获得的静脉血样本的已知血清放射性测量值。在体外使用肿瘤组织的伽马井计数和数字放射自显影术获得了可比的测量结果。结果：肿瘤在体内和体外的放射性测量值存在显著相关性（归一化PET测量值与孔计数的Spearman相关系数为0.84,P < 0.000001，与放射自显影的Spearman相关系数为0.88,P < 0.000001）。PET/CT对肿瘤摄取的测量值低于用任何一种体外方法获得的测量值，而数字放射自显影的测量值最高。结论：PET/CT可可靠地用于定量放射性标记的大分子在体内的摄取，这对大分子生物分布的定量药代动力学估计具有重要意义。
The goal of this study was to determine whether there is a potential correlation between quantification of radiolabeled macromolecular uptake in tumors determined in vivo using PET/CT and in vitro using autoradiography and gamma-counting of tumor tissue. Methods: Twenty-six patients with renal masses scheduled for surgical resection received I-124-labeled antibody cG250. Tumor specimens obtained from resection were studied. Fifteen of these patients had clear cell cancer demonstrated by positive findings on PET/CT images and histopathology. Radioactivity in tumors was measured on PET/CT images and expressed as percentage injected dose per gram. These values were then normalized to measurements of known serum radioactivity from a venous blood sample obtained at the time of PET/CT. Comparable measurements were obtained in vitro using gamma-well counting and digital autoradiography of tumor tissue. Results: There was a significant correlation between tumor radioactivity estimated in vivo and in vitro (Spearman correlation coefficient comparing normalized PET measurements with well counting of 0.84, P < 0.000001, and with autoradiography of 0.88, P < 0.000001). PET/CT measurements of tumor uptake were lower than measurements obtained with either of the in vitro methods, and digital autoradiography resulted in the highest measurements. Conclusion: PET/CT can be reliably used to quantify radiolabeled macromolecular uptake in vivo, suggesting important implications for quantitative pharmacokinetic estimates of macromolecular biodistribution.