[Renal cell cancer in childhood]

Renal cell carcinoma is a rare disease in children and difficult to distinguish from Wilms-tumor before surgery. We present case histories of two children with renal cell carcinoma and discuss the problems of differential diagnosis versus nephroblastoma, therapy and prognosis. In contrast to Wilms-tumors, the most common kidney-tumor in children occurring mostly in young infants, renal cell carcinoma is rare in childhood and predominantly manifests in school-age. Only a few cases of renal cell carcinoma in younger children are described in the literature. Diagnostic imaging cannot reliably distinguish renal cell carcinoma from other neoplasm of the kidney. However, hematuria in patients with small tumors or no response to preoperative chemotherapy may indicate the presence of renal cell carcinoma rather than nephroblastoma. The determination of "tumor-associated trypsin inhibitor" (TATI) might give further contribution of differential diagnosis. It was measured only in one of our patients and was markedly elevated. Complete surgical resection (nephrectomy with lymphadenectomy) is a curative therapy in patients with tumors limited to the kidney. Chemotherapy and irradiation show no convincing effect. In metastatic tumors therapy with interleukin 2 may be successful.