[Congenital cyst adenomatoid malformation of the lung]

The authors report two cases of Congenital Cyst Adenomatoid Malformation diagnosed by ultrasound in the 24th and 27th weeks of pregnancy. The pregnancies had no other problems until their term and deliveries were normal. Surgical resection of the malformation was made on the 8th day of life in one child and on the 11th day in the other. After 2 years, the first child shows a good evolution in weight and height, without lung pathology. After 2 months, the other child also shows a similar condition.