肾血管平滑肌脂肪瘤与肾癌的CT鉴别诊断

CT Differentiation of Renal Angiomyolipoma and Renal Cell Carcinoma

目的 探讨肾血管平滑肌脂肪瘤 (RAML)与肾细胞癌 (RCC)的 CT鉴别征象 ,以提高不典型 RAML的诊断水平。方法 回顾性分析双期增强 CT扫描的 RAML 36例 (5 7个病灶 ) ,RCC4 6例。运用 χ2检验确定有显著性差异的 CT观察指标进行判别分析 ,得到各指标在鉴别诊断中的权重。结果 单发或多发、边缘、分叶征、病灶突出比、与实质的分界、与皮质的交角、皮质掀起征、肿瘤内血管影、钙化等 9项 CT观察指标对 RAML与 RCC的鉴别有统计学意义 ,利用最大似然法判别分析对二者诊断的准确率分别为 :RAML组 93.0 % ,RCC组 89.1%。结论 病灶突出比、与皮质的交角、皮质掀起征及肿瘤内血管影特征对二者鉴别诊断起重要作用。

Objective To improve the diagnosis of atypical renal angiomyolipoma (RAML) by use of CT to differentiate RAML from renal cell carcinoma (RCC). Methods We retrospectively analyzed the CT manifestations with dual-phase enhanced contrast study in 36 cases of RAML (with 57 lesions) and 46 cases of RCC. 25 lesions of RAML and all RCC were histologically confirmed. Maximum likehood estimator was employed to discriminate all the lesions according to a series of indexes with statistical meanings. Results Nine indexes were found to be significant and evident for separating RAML from RCC, namely “single or multiple”, border, lobulation, protrusion rate, interface with cortex, angle with cortex, “levering-cortex-up” sign, characters of blood vessel in lesion and calcification. The accuracy rates of discrimination analysis for RAML and RCC were 93.0% and 89.1%, separately. Conclusion The importance of 4 indexes, including protrusion rate, angle with cortex, “levering-cortex-up” sign and the traits of blood vessel, should be highlighted in the differentiation of RAML and RCC.