后肾腺瘤的CT特征分析

目的:分析后肾腺瘤（MA）的CT表现及病理学特征，以提高其术前诊断准确率。资料与方法:回顾性分析5例经手术病理证实为MA患者的CT影像资料及病理学特征，结合文献并总结MA的MSCT表现及病理学特征。结果:5例患者中，均为女性，年龄35～58岁，平均48岁，均为单发。病灶形态呈类圆形，平均直径约7.5cm。5例病灶向肾集合系统或/及肾外突起，对周围结构压迫推移，无局部侵犯及转移。5例平扫病灶密度与肾实质相仿，密度不均匀，病灶内未见出血、钙化及包膜。增强扫描5例病灶表现为渐进性不均匀强化，皮质期呈轻度强化，实质期呈轻-中度强化，排泄期呈中度强化，2例可见低密度纤维瘢痕。病理显示:MA范围及形状与大体标本切面趋于一致，与周围肾组织界限清楚。MA的细胞呈小腺管样排列，胞浆少，核小，未见核分裂象和坏死，免疫组化Ki-67（+，<5％）、β-catenim（+）、CK（+）、CK7（+）。结论:MA的CT表现具有一定的特征性，结合女性患者出现红细胞增多症，有助于提高MA的术前诊断准确率。 

CT Feature Analysis of Metanephric Adenoma

Objective: to analyze CT features and pathological features of metanephric adenoma in order to improve the preoperative diagnostic accuracy of MA. Data and methods: CT imaging data and pathological features of 5 patients with MA confirmed by surgical pathology was retrospectively analyzed, and MSCT manifestations and pathological features of MA were summarized in combination with literature. Results: all the 5 patients were female, aged 35-58 years, with an average age of 48 years. The lesions were almost round in shape with an average diameter of about 7.5cm. In 5 cases, the lesion protruded into the renal collecting system or/or the renal extrorenal system, and the surrounding structures were compressed and pushed, without local invasion or metastasis. The density of the lesions on plain scan was similar to that of renal parenchyma, but the density was not uniform. There was no bleeding, calcification or capsule in the lesions. In 5 cases, progressive heterogeneous enhancement was observed in the lesion on enhanced scan, mild enhancement was observed in the cortical phase, mild to moderate enhancement was observed in the parenchymal phase, and moderate enhancement was observed in the excretory phase. Low-density scar was observed in 2 cases. Pathology showed that the MA range and shape tended to be consistent with the section of the gross specimen, and was clearly demarcated from the surrounding renal tissue. MA cells were arranged in small glandular tubules with few cytoplasm and small nuclei. No mitotic figure and necrosis were observed. Immunohistochemical ki-67 (+, < 5%), -catenim (+), CK (+) and CK7 (+) were detected. Conclusion: the CT manifestations of MA have certain characteristics, combined with the occurrence of erythrocythemia in female patients, which is helpful to improve the preoperative diagnosis accuracy of MA.