肾嫌色细胞癌的影像表现与病理对照分析

The comparative study of the imaging features of chromophobe cell renal carcinoma with pathologic findings

目的分析肾嫌色细胞癌(CCRC)的影像表现特征并与病理结果进行对照,以提高诊断准确性。方法回顾性分析了12例 CCRC 的资料,其中10例经 CT 检查,包括平扫、皮质期和髓质期动态增强扫描(1例无皮质期扫描)。2例经 MR 检查,包括平扫 T_1WI、T_2WI 及皮质期和髓质期动态增强 T_1WI。结果病灶位于左肾4例,右肾8例,最大径24.0～125.0 mm,平均56.7 mm。10例CT 检查中,6例在平扫上密度均匀一致,5例增强后扫描强化均匀一致,与病理上该肿瘤较少发生坏死、囊变、出血对应。皮质期,9个病灶的强化程度均高于髓质,低于皮质,强化程度与微血管密度密切相关;髓质期,10个病灶密度均明显低于髓质。2个体积较大的病灶内见中央星状瘢痕。4个病灶周围见假包膜。MR 检查的2例相对于髓质,病灶在平扫 T_1WI 上呈高信号,在 T_2WI 上,表现为明显的低信号。病灶的强化方式与 CT 相似。结论 CCRC 在 CT 及 MRI 上的均质性特点、独特的强化方式及 T_2WI 上呈相对于髓质的明显低信号,具有一定的特征性,有助于与其他肿瘤鉴别。

Objective To analyze and compare the imaging features of chromophobe cell renal carcinoma（CCRC） with pathologic findings in order to improve the diagnostic accuracy. Methods The data of CT and MRI of 12 patients with CCRC were reviewed retrospectively. Ten patients underwent CT examination, including precontrast scan, the contrast corticomedullary phase scan and the parenchymal phase scan （one patient without corticomedullary phase scan）. Two patients underwent MR examination including precontrast T1 WI, T2WI and enhanced T1WI of the cortieomedullary phase and the parenchymal phase. Results Four lesions located in left kidney and eight in fight kidney. Maximum diameter of lesions ranged from 24 nun to 125 nun, average 56. 7 nun. Homogenous density was observed in six lesions of ten on unenhanced CT scan and five lesions had homogenous enhancement on enhanced CT scan, which was due to the less incidence of necrosis, liquefaction and hemorrhage on pathologic findings. Nine Lesions showed hyperdense compared with renal medulla but the density was lower than renal cortex on the corticomedullary phase. The enhanced degree was positively correlated with microvessel density （ MVD ）. All ten lesions became hypodense compared with renal medulla on the parenchymal phase scan. Central stellate scar was found in two big lesions and psudocapsula were observed in four lesions confirmed by pathology. Two patients underwent MRI examination. Compared with medulla, the two lesions showed hyperintense on unenhanced T1 WI and obviously hypointense on unenhanced T2 WI. The enhancement pattern of them was similar to CT. Conclusion The imaging features of CCRC, such as homogeneity, special enhancement pattern and distinct hypointensity on T2WI , help to differentiate CCRC from other renal tumors.