Genetic aspects of childhood tumours.

Present concepts on the etiology of childhood tumours are reviewed. The difference in clinical manifestations of the hereditary and nonhereditary types are illustrated with data on retinoblastoma and on nephroblastoma. Notwithstanding these differences it is most likely that the fundamental etiologic process is the same in both and that it consists in successive mutational events. The possible consequences of the association of retinoblastoma with a deletion of chromosome 13 in some cases are discussed. Several explanations for the association of Wilms' tumour and aniridia are also discussed.