Prenatal diagnosis of congenital cystic adenomatoid malformation.

Congenital cystic adenomatoid malformation (CCAM) of the lung is a rare pulmonary lesion. The prognosis is variable ranging from perinatal death to spontaneous in utero regression, with no neonatal morbidity. We present a case of CCAM diagnosed at 23 weeks' gestation using results of prenatal sonograms. Both prenatal Two-Dimensional and Three-Dimensional sonograms revealed multiple cystic lesions at the right lower lung field. Regular serial antenatal sonograms revealed the fetus had persistent right lower lung multicyst lesions but had no hydrops fetalis or associated congenital anomalies. The results of the antenatal 50 g glucose diabetic screen at 24 weeks' gestation were normal. A live male baby was vaginally delivered smoothly at 40 weeks' gestation. Body weight was 4170 g. Apgar scores were 7 at 1 minute and 8 at 5 minutes. The newborn had no signs of respiratory distress at birth. Postnatal chest computed tomography (CT) also revealed multiple fluid-filled cysts in the right lower lobe compatible with congenital cystic adenomatoid malformation. Because of the potential risk of perinatal death, repeated lung infection and malignant change of CCAM, the newborn received right lower lung lobectomy 1 week after delivery. Pathology confirmed the diagnosis of CCAM type II. The recovery was smooth postoperatively and the baby still receives regular follow-up. We emphasize the importance of prenatal diagnosis of CCAM and early removal of the congenital cystic lesions of the lung to achieve a good outcome.