Genetics of paediatric solid tumours.

Abstract

The average child in the UK stands a 1:600 chance of developing a malignancy by the time they are 16 years of age, which compares with the 1 in 5 adults who die of cancer. The tumours children develop are very different from those seen in adult life. Histologically they resemble their relatively undifferentiated, fetal counterparts rather than the fully differentiated structures seen at, or soon after birth. The genetic events responsible for initiating children's tumours, therefore, must occur during embryonic life and prevent normal differentiation. These cells are frozen in the undifferentiated state and the malignant phenotype eventually arises as a result of secondary changes. The acquisition of secondary events occurs at varying rates and accounts for the variation in the time of presentation of the tumour. Unlike the adult situation environmental factors have not been identified as common causes of genetic damage in children's tumours.