Non-Wilms’ Renal Tumors

Abstract

AbstractAlthough Wilms’ tumor (WT) is the most common pediatric solid renal tumor accounting for 6–7% of all childhood cancers, there are many other rare renal neoplasms which may mimic its presentation. These tumors collectively account for 10–15% of all primary renal neoplasms of childhood and are grouped together as non-Wilms’ renal tumors (NWRT). They are heterogeneous and include a wide spectrum of benign and malignant tumors with varying biological behavior, malignant potential, and prognosis. Congenital mesoblastic nephroma (CMN), clear-cell sarcoma of the kidney (CCSK), and malignant rhabdoid tumor of the kidney (MRTK) are some of the frequently reported types, while multilocular cystic renal tumors, renal cell carcinoma (RCC), angiomyolipoma, renal medullary carcinoma, metanephric adenoma, ossifying renal tumor of infancy, primitive neuroectodermal tumor, and lymphoma are some of the uncommon NWRT of childhood. The biological and clinical behavior of this group of tumors is poorly understood due to their heterogeneity and rarity. The learning objectives of this chapter are to know the salient clinical, radiological, and histopathological features of these tumors to minimize diagnostic uncertainties and accurate differentiation from WT. This review also emphasizes the differences in management protocols especially chemotherapeutic regimens between WT and NWRT. Risk stratification of these tumors based on genetic profiling and the recent advances in their management are also discussed.KeywordsNon-Wilms’ renal tumorsCongenital mesoblastic nephromaClear-cell sarcoma of the kidneyMalignant rhabdoid tumor of the kidneyCystic renal tumorsCystic nephromaCongenital partially differentiated nephroblastomaRenal cell carcinomaRenal angiomyolipomaRenal medullary carcinomaMetanephric adenomaOssifying renal tumor of infancyPrimitive neuroectodermal tumor of the kidneyPrimary renal lymphoma