Childhood kidney cancers account for about 7 percent of all childhood cancers. Most childhood kidney cancers are Wilms tumor, but in the 15- to 19-year age group, most tumors are renal cell carcinoma.
According to the National Cancer Institute, about 650 cases of Wilms tumor are diagnosed in the United States each year. While this type of tumor typically develops in otherwise healthy children, about 10 percent of children with Wilms tumor have been reported to have a congenital anomaly.
Other types of childhood kidney tumors include rhabdoid tumors, clear cell sarcoma, congenital mesoblastic nephroma, neuroepithelial tumors, desmoplastic small round cell tumor, cystic partially differentiated nephroblastoma, multilocular cystic nephroma, primary renal synovial sarcoma, and anaplastic sarcoma. Nephroblastomatosis of the kidney is a type of nonmalignant neoplasia.
Source: National Cancer Institute