The pathology of congenital lung lesions.

The spectrum of complications associated with congenital lung malformation is wide. They can range from fetal hydrops in utero to postnatal problems of ventilation, obstruction and infection; presentation may occur from the neonatal period to adulthood. Many lesions will remain asymptomatic while at the other end of the complication spectrum, there is a small risk of neoplasia associated with some forms of cystic lung. A better understanding of the pathology has shown that bronchial atresia/obstruction is the likely hidden pathology underlying many congenital lung lesions leading to downstream cystic maldevelopment. Earlier diagnosis has led to increasing difficulties in ascribing malformations to conventional categories that were originally described in postnatal lungs. It is probably more important to be aware of the potential combination of vascular and airway connections and complications than to try and prescribe a classification of pulmonary lesions associated with rigid definitions.