[Rare childhood kidney tumors].

Pediatric kidney tumors are rare and account for about 6% of all childhood malignancies. By far the most common tumors are nephroblastomas. This review presents rare childhood renal tumors. Mesoblastic nephroma, as tumors of the low risk group, as well as the clear-cell sarcomas of the kidney and malignant rhabdoid tumors, as tumors of the high-risk group, and the so-called anaplastic sarcomas of the kidney will be discussed.Due to the significantly divergent therapy, a correct diagnosis is important. Due to the often overlapping morphology, pathologic diagnosis is often difficult. In addition to the typical morphologic features, the specific immunohistochemical aspects as well as the known molecular changes will be presented.