Clear cell sarcoma of the kidney in a 4-month-old infant: a case report.

A case of clear cell sarcoma of the kidney is described in a 4-month-old male infant. The tumor had a typical histological pattern, consisting of sheets of tumor cells possessing "empty" nuclei set within a delicate capillary network. There was extensive necrosis and tumor cell cytoplasm contained vimentin. This tumor occurs only rarely in infants less than six months of age. The different renal neoplasms of childhood have diverse prognoses and demand specific therapy so that accurate diagnosis is mandatory. The present case illustrates that clear cell sarcoma, a highly malignant neoplasm, must be considered in the differential diagnosis of a renal mass occurring in this age group.