ABSTRACT
The pathology of development encompasses processes related to extra-embryonic tissues, formation of the embryo, growth of the fetus, birth and adaptation to life outside the uterus. Congenital malformations have been known to humankind since the dawn of time. Serious malformations are due to a localised error of structural development occurring in the eight weeks following conception. Developmental tumours are a rare cause of death in the perinatal period but some may be lethal in childhood. The three main types of developmental tumour are hamartomas, teratomas and the family of malignant tumours of childhood or ‘blastomas’. The concept of neoplasia will need to be broadened to include some that rarely if ever progress to cancer, others that have a low risk and a group with a higher risk of progression. The principal characteristic unifying neoplasia will be a localised disorder of growth caused by one or more genetic mutations.
