Outcome of the prenatally diagnosed congenital cystic adenomatoid lung malformation: A Canadian experience

Congenital cystic adenomatoid malformation of the lung (CCAM) is diagnosed by prenatal ultrasonography with an increasing frequency but controversy pe rsists as to its prognosis and prenatal management. Method: A multiinstitut ional study of cases of CCAM diagnosed antenatally identified by ultrasonog raphers and by a review of hospital charts. Results: We obtained 48 cases f rom five centers. We estimate the incidence of CCAM at 1:25,000 to 1:35,000 pregnancies. The incidence of voluntary abortions was 15% (7/48), of spont aneous abortions 2% (1/41) and of postnatal death 10% (4/40). One of the po stnatal deaths was from trisomy 18. Of the 7 aborted fetuses, 2 had multipl e malformations and 1 had severe hydrops and oligohydramnios; the other 4 h ad a large mass with mediastinal displacement but without hydrops. When pre gnancy was allowed to continue, 56% of the lesions regressed spontaneously, even though one third of these had initial progression. In 17 cases (42%) the mediastinal shift corrected itself, sometimes by simple growth of the f etus but most often by a decrease in the size of the lung mass. In 1 fetus, repeated needle decompressions followed by double-pigtail catheter drainag e of large cysts allowed regression of hydrops. Despite this, neonatel deat h occurred from pulmonary hypoplasia. Conclusion: CCAM can lead to fetal or neonatal demise from hydrops, lung hypoplasia, prematurity or severe assoc iated malformations, but has a good prognosis in the majority of cases. Cop yright (C) 2001 S. Karger AG, Basel.