儿童肾脏恶性肿瘤的CT诊断和鉴别诊断

目的 探讨儿童肾脏恶性肿瘤的CT表现及特点。材料与方法 回顾性分析53例经临床病理证实的小儿肾脏恶性肿瘤，其中Wilms瘤45例，肾透明细胞肉瘤3例，肾细胞癌3例，肾恶性横纹肌样瘤、肾胚胎性横纹肌肉瘤各1例。结果 45例Wilms瘤中76%呈实质性肿块，4%为囊性，20%为囊实性；增强后肿瘤实质部分、囊壁及间隔有强化；9%见斑点或斑片状钙化。肾脏恶性非Wilms瘤在CT上边界清晰或模糊的类球形、密度欠均匀的实质性肿块，增强后轻～中等度强化，8例中5例（63%）见斑点或斑片状钙化。肾恶性横纹肌样瘤见实质内点状及条索状强化血管影。肾胚胎性横纹肌肉瘤表现为肾实质及肾盂内分叶状实质性肿块，侵犯肾门及输尿管上段，肾周见新月形低密度的包膜下积液。结论 CT对儿童肾脏恶性肿瘤的术前诊断及提出随访方案上有一定帮助。

CT Diagnosis and Differentiation of Malignant Renal Tumors in Children

Objective To study CT findings and characteristics of malignant renal tumors in children.Materials and Methods CT findings in 53 children under 12 years old with malignant renal tumor, encountered in the past 7 years, were retrospectively analyzed. Pathologically, the tumors included Wilms' tumor (n=45), clear cell sarcoma (n=3), renal cell carcinoma (n=3), malignant rhabdoid tumor (n=1) and rhabdomyo sarcoma (n=1).Results Of 45 Wilms' tumors, 76% presented as solid masses, 4% were cystic and 20% were mixed. Calcification was seen in 9% of Wilms' tumors. On CT scan, non Wilms' tumors presented as oval masses of heterogeneous density with clear or blurred margin and mild moderate enhancement after contrast administration. Of 8 patients with non Wilms' tumor, 5 (63%) showed irregular patchy calcifications. The malignant rhabdoid tumor showed multiple linear or spotted enhanced blood vessels. The rhabdomyosarcoma showed signs of lobular solid mass within the renal parenchyma, pelvis or upper part of the ureter, with crescent low density subcapsular hematoma surrounding the kidney.Conclusion CT is useful in the diagnosis of children's malignant renal tumors and in the making of follow up plan.