肾脏少见病变CT诊断(附4例误诊肾细胞癌的病例报道)

CT Diagnosis of Infrequent Diseases of Kidney(with Report of four Cases that were misdiagnosed as Renal Carcinoma)

目的:分析4例误诊肾细胞癌的肾脏少见病变CT影像学表现,以期提高对这类病变的认识能力。方法:描述4例误诊肾细胞癌的肾脏少见病变临床与CT影像学表现。4例肾脏病变分别为肾血管畸形伴囊肿出血1例,肾神经内分泌癌(不典型类癌)1例,肾平滑肌瘤1例,肾结核1例。CT行平扫及3期增强扫描,其中2例作多平面重建(MPR)观察。结果:肾平扫等高混杂密度肿块及增强后对比剂圆弧形压迹可支持肾血管畸形伴囊肿出血的诊断。肾神经内分泌癌所示肾内肿块强化幅度不同于常见肾细胞癌。左肾平滑肌瘤表现为肾内球形肿块,境界光整,强化均匀,符合肾平滑肌瘤特征。左肾结核患肾病变内低密度灶境界锐利,肾皮髓质纹理模糊,符合肾结核乳头炎及结核脓腔的病理特点。结论:肾脏少见病变常难与肾癌鉴别。CT三期增强扫描和多平面重组常有必要。仔细观察病灶的形态、范围和强化情况,有助于作出正确判断。

Objective：To analyze the CT imaging manifestations of infrequent renal diseases which were misdiagnosed as renal carcinoma, and to improve the understanding of the renal diseases. Methods：Four cases of renal diseases which were misdiagnosed as renal cell carcinoma were studied. The pathological changes in 4 cases were as follows：vascular malformation of kidney with cyst and bleeding （one case）, neuroendocrine carcinoma of kidney （atypical carcinoid） （one case）, leiomyoma of kidney （one case） and tuberculosis of kidney （one case）. CT plain scan and triphasic enhancement scan were performed in all cases and multiplanar reformation （MPR） was done in 2 cases. Results：On the precontrast images a tumor with iso- and hyper-density and circular compression of contrast agents after administration of contrast material supported the diagnosis of vascular malformation of kidney with bleeding cyst. Neuroendocrine carcinoma displayed unusual enhancement of tumor differing from usual renal cell carcinoma. Leiomyoma of kidney displayed sharply outlined round mass with homogeneous enhancement which corresponded with some traits of leiomyoma. Sharply outlined hypodense lesion without enhancement,and blurred texture of cortex-medulla of kidney were basically corresoponded with renal papilla inflammation and pu- rulent cavity of tuberculous focus. Conclusion： Infrequent renal diseases are often difficult to be differentiated from renal car- cinoma. CT triphasic enhanced scan and MPR are often necessary. Careful observation and analysis of the form and extent of the lesion and degree of the enhancement may help to make correct diagnosis.