少见类型肾细胞癌的MRI表现及鉴别诊断

目的 观察少见类型肾细胞癌的MRI表现。方法 回顾性分析经手术及病理证实少见类型肾细胞癌10例患者的资料，患者均接受MRI平扫及增强扫描。观察分析MRI表现及其鉴别诊断价值。结果 10例中，多房囊性肾细胞癌3例，乳头状肾细胞癌4例，嫌色肾细胞癌2例，集合管癌1例；8例病灶位于右肾，2例位于左肾。4例乳头状肾细胞癌反相位信号略减低，2例嫌色肾细胞癌及1例集合管癌反相位信号未见明确减低。10例实性部分DWI序列呈高、略高信号。3例多房囊性肾细胞癌均见分隔及壁结节，其中1例分隔及壁结节明显强化，2例分隔及壁结节轻中度强化；4例乳头状肾细胞癌、2例嫌色肾细胞癌及1例集合管癌均轻度强化。结论 MRI能提供少见类型肾细胞癌更多的影像信息，对其诊断及鉴别诊断有重要的参考价值，有助于术前明确诊断。

MRI features and differential diagnosis of rare type renal cell carcinoma

Objective To observe the MRI manifestations of rare type renal cell carcinoma. Methods Data of 10 patients with rare types of renal cell carcinoma confirmed by surgery and pathology were retrospectively analyzed. All patients underwent MRI scan and enhanced scan. MRI manifestations and differential diagnosis were discussed. Results Among 10 cases, there were multilocular cystic renal cell carcinoma of 3 cases, papillary renal cell carcinoma of 4 cases, chromophobe renal carcinoma of 2 cases and collecting duct carcinoma of 1 case. Eight lesions were located in the right kidney, 2 lesions were located in the left kidney. The reveal of out-of-phase signals were slightly lower in 4 cases of papillary renal cell carcinoma. For 2 cases of chromophobe renal carcinoma and 1 case of collecting duct carcinoma, the phase signal were not clear cut. DWI sequence of solid parts of 10 cases showed high and slightly high signal. For 3 cases of multilocular cystic renal cell carcinoma, the separate and mural nodules were found, including 1 case with separated and mural nodule significantly enhancement, 2 cases with separation and mural nodules mild-to-moderate enhancement. The mild enhancement were revealed in 4 cases of papillary renal cell carcinoma, 2 cases of chromophobe renal carcinoma and 1 case of collecting duct carcinoma. Conclusion MRI can provide more image informations for diagnosis and differential diagnosis of rare types of renal cell carcinoma, which is helpful to diagnose preoperatively.