能谱CT鉴别肾脏嗜酸性细胞腺瘤和嫌色细胞癌

Energy spectrum CT for differentiating renal oncocytoma and chromophobe renal cell carcinoma

目的观察能谱CT多参数鉴别诊断肾脏嗜酸细胞腺瘤(RO)与嫌色细胞型肾癌(CRCC)的价值。方法回顾性分析经手术病理证实的12例RO(RO组)和30例CRCC(CRCC组)患者,测量并计算皮/髓质期70 keV单能量CT值、碘浓度(IC)、标准化碘浓度(NIC)、水浓度(WC)、有效原子序数及40~70 keV能谱曲线斜率(λ值)。比较2组常规CT征象及能谱CT参数差异,以ROC曲线评估差异有统计学意义的参数鉴别RO与CRCC的效能。结果2组常规CT显示病灶中心瘢痕出现率差异有统计学意义(χ^2=3.038,P=0.046)。能谱CT参数中,RO组皮/髓质期70 KeV单能量CT值、IC、有效原子序数、λ值及皮质期NIC均高于CRCC组(P均<0.05),髓质期NIC及皮/髓质期WC与CRCC组差异均无统计学意义(P均>0.05)。以皮质期λ值5.68为阈值鉴别RO与CRCC的AUC最高为1.00(P<0.01),敏感度及特异度均为100%。结论能谱CT参数,包括皮/髓质期70 keV单能量CT值、IC、有效原子序数、λ值及皮质期NIC对鉴别RO与CRCC具有一定价值。

Objective To observe the value of energy spectrum CT multi-parameter for differential diagnosis of renal oncocytoma(RO)and chromophobe renal cell carcinoma(CRCC).Methods Data of 12 patients with RO(RO group)and 30 patients with CRCC(CRCC group)confirmed by surgery and pathology were retrospectively analyzed.The 70 keV single-energy CT value,iodine concentration(IC),normal iodine concentration(NIC),water concentration(WC),effective atomic number and the slope of 40-70 keV energy spectrum curve(λvalue)in cortical/medulla phase were measured and calculated.Conventional CT signs and energy spectrum CT parameters were compared between the two groups.ROC curves of parameters being statistically different between groups were drawn for differential diagnosis of RO and CRCC,and the corresponding diagnostic efficacies were analyzed.Results The presence of scar in the center of lesions were statistical different between groups on conventional CT(χ^2=3.038,P=0.046).Energy spectrum CT showed that the 70 keV single-energy CT value,IC,effective atomic number,λvalue in cortical/medulla phase and the cortical phase NIC in RO group were higher than those in CRCC group(all P<0.05).There was no statistically significant difference of the medulla phase NIC and cortical/medulla phase WC between RO group and CRCC group(all P>0.05).Taken 5.68 as the threshold value of the cortical phaseλvalue for distinguishing RO from CRCC,the highest AUC was 1.00(P<0.01),and the sensitivity and specificity were both 100%.Conclusion Energy spectrum CT multi-parameter,including cortical/medulla phase 70 keV single-energy CT value,IC,effective atomic number,λvalue and cortical phase NIC had a certain value for distinguishing RO from CRCC.