CT双相扫描鉴别乏脂肪性肾血管平滑肌脂肪瘤与肾细胞癌的价值

目的:通过比较乏脂肪性肾血管平滑肌脂肪瘤(AML)与肾细胞癌(RCC)的各种CT特征,评价CT在鉴别诊断中的价值。方法:回顾性分析了7例均病理证实的乏脂肪性AML和22例RCC的CT平扫和双相增强扫描(皮髓质相和早期分泌相)资料。结果:乏脂肪AML呈不均匀密度2例(28.6%),RCC组,不均匀密度14例(63.2%),两组不均匀率差异显著(P<0.05)。均匀强化和延迟强化发生率AML组为71%(5/7)和57.1%(4/7),RCC组为14%(3/22)和9%(2/22),经多变量逻辑回归分析,肿瘤的强化模式是鉴别AML和RCC的有价值的预测指标,其阳性和阴性预测值分别为80%(4/5)和86.9%(20/23)。结论:应用CT对比剂双期扫描,肿瘤的强化模式对于鉴别AML和RCC具有重要价值。

The vlaue of biphase helical CT differentiating AML with minimal fat from renal cell carcinoma

Objective:To evaluate the value of CT in differentiating angiomyolipoma(AML) with minimal fat from ranal cell cancirnoma(RCC) by comparing their various CT features.Methods:The CT features(unenhanced,corticomedullary,and early excretory phase scanning)of seven cases with AML and 22 cases with RCC proved pathologically were analysed retrospectively.Results:28.6%(2/7) of AML and 63.2%(14/22) of RCC manifest a heterogeneous attenuation in unenhanced CT scan,Homogeneous enhancement were observed in 71% of AML vs 14% of RCC,and prolonged enhancement pattern were observed in 57.1%of AMLvs 9% of RCC.When both CT findings were used as a criteria for differentiating AML from RCC,positive and negative predictive values were 80%(4/5) and 86.9%(20/22) respectively.Conclusion:Biphase helical CT is useful in differentiating AML with minimal fat from RCC,with homogeneous tumor enhancement and prolonged enhancement pattern being the most valuable CT findings.