Congenital cystic adenomatoid malformation. A report of three unusual cases.

Most children with congenital cystic adenomatoid malformation present in the first six months of life. Three cases are described with unusually late presentation. One child was completely asymptomatic and another became symptomatic only after secondary infection of a congenital cystic adenomatoid malformation. In two cases the correct diagnosis was not made preoperatively. The value of preoperative lung scanning was demonstrated in one case in which a lung scan showed a larger perfused area than indicated on the radiograph. At operation, a lobulated cystic structure was seen attached by a thin pedicle to the interior surface of the left upper lobe.