Neonatal outcome of antenatally diagnosed congenital cystic adenomatoid malformations

Objective: To investigate the natural history and outcome of antenatally diagnosed congenital cystic adenomatoid malformation (CCAM) of the lung.

Methods: This was a retrospective study of all cases of fetal CCAM of the lung diagnosed antenatally. All cases were referred to a tertiary center for further management. A computer search identified all referred cases, and the records of these patients were examined to determine the pregnancy outcome.

Results: In a 4-year period, 34 cases of fetal CCAM were referred for further management. At presentation, all the cases were noted to be unilateral CCAMs and the majority (79%) were microcystic in nature. The CCAMs were complicated by varying degrees of mediastinal shift (79%) and hydrops fetalis (18%). During the course of the pregnancy, the lung lesion was seen to reduce in size or resolve spontaneously in 76% of cases without any prenatal intervention (including resolution of hydrops in three cases). The overall survival rate into infancy was 88%. One pregnancy was terminated for persisting hydrops fetalis and another resulted in infant death from complications of neonatal cardiac surgery for an associated aortic coarctation.

Conclusion: The outcome of antenatally detected CCAM is much better than previously reported even when complicated by hydrops fetalis at presentation. The latter seems to be related to the high spontaneous regression rate of this tumor. Despite the antenatal resolution of CCAMs on ultrasound, postnatal follow-up is recommended in view of the long-term complications of this malformation.