分析和探讨肾脏罕见恶性肿瘤的CT影像学表现特点。

回顾性分析2008年12月至2018年10月，广州市第一人民医院及红十字会医院18例经手术及病理证实的肾脏罕少见恶性肿瘤的CT影像学资料。

18例恶性病变分别为恶性纤维组织细胞瘤1例，CT平扫肿瘤边界不清，密度不均，瘤内见片状密度减低区，增强扫描肿瘤轻度延迟强化。平滑肌肉瘤1例，CT平扫肿瘤边界略清，密度不均，瘤内见大片状密度减低区，增强扫描肿瘤轻度延迟强化。肾实质浸润型尿路上皮癌1例，CT平扫双肾多发不规则软组织肿块，平扫密度不均匀，增强扫描强化不均匀。囊性肾癌6例，呈囊性病灶，增强扫描囊性成分未见明确强化，病灶内可见强化分隔及絮状强化影。嫌色细胞癌9例，平扫密度均匀或不均匀，增强扫描6例呈轻中度延迟强化，3例呈"快进快退"表现。CT扫描对18例肿瘤的诊断准确率为72.2%（13/18）。

肾脏罕见恶性肿瘤具有一定的CT影像学特点，可为临床诊断及术前评估提供重要依据，但确诊仍需依靠病理学。

To explore the CT imaging features of primary renal rare malignant tumors.

From Dec. 2008 to Oct. 2018, 18 patients with primary renal rare malignant tumors pathologically proven lesions after operation who had CT exams with contrast were enrolled in our hospitals. The CT imaging features of all tumors were analyzed respectively.

18 malignant tumors were malignant fibrous histiocytoma (MFH,n=1), renal leiomyosarcoma (RLMS,n=1), invasive renal parenchyma urothelial carcinoma (IRPUC,n=1), cystic renal cell carcinoma (CRCC,n=6), chromophobe renal cell carcinoma (CPRCC,n=9) respectively. MFH with unclear border showed heterogeneous density with patchy necrosis on CT precontrast and slight delayed enhancement. RLMS with clear border showed heterogeneous density with patchy necrosis on CT precontrast and slight delayed enhancement. IRPUC showed multiple lesions with heterogeneous density on CT precontrast and slight heterogeneous enhancement. CRCC showed cystic lesions on CT precontrast. Various degrees of septum and floc enhancement were detected after intravenous administration of contrast material. CPRCC showed mixed isodensity and hypodensity on CT precontrast followed by slight/moderate delayed enhancement (n=6) or washout enhancement (n=3). The diagnostic accuracy rate of CT for renal rare malignant tumors was 72.2%(13/18).

Special CT imaging characteristics for primary renal rare malignant tumors had certain value for diagnosis and preoperative assessment. However, the finial diagnosis still depends on pathology.