Cystic adenomatoid malformation of the lung (CAML) is a rare pulmonary maldevelopment resulting from an abnormal growth of the terminal bronchial structures. This study proposes a possible management of prenatally diagnosed CAML. A group of nine cases of CAML diagnosed prenatally between January 1990 and December 1995 was studied retrospectively. The evolution of lesions was followed in utero by serial ultrasound monitoring. Chest X-ray was performed at birth in all neonates and CT only in the symptomatic ones. CAML was macrocystic in three cases and microcystic in six. No polyhydramnios, hydrops or associated malformations were seen. In four cases, CAML was confirmed at birth and required surgery. The lesion decreased in size prenatally in five fetuses, of whom only one underwent surgery. In two further cases a prenatal diagnosis of CAML was changed to diaphragmatic hernia.
Conclusion: Given the possible clinical disappearance or resolution of cystic adenomatoid malformation of the lung, we believe that surgery is justified at birth only in symptomatic and radiologically positive neonates. It could be safely delayed in those asymptomatic patients with either positive or negative chest X-ray. The former need computed tomography at birth, whereas, in the latter, it should be performed at 6 months of age for a more definitive assessment of the patient.