Fetal thoracoamniotic shunting for large macrocystic congenital cystic adenomatoid malformations of the lung

Abstract

Objective: To evaluate fetal thoracoamniotic shunting for isolated large macrocystic congenital cystic adenomatoid malformations (CCAM) of the lung.

Methods: This was a retrospective study of 11 fetuses with macrocystic CCAM who underwent thoracoamniotic shunting. This procedure was offered if fetal hydrops or signs of evolving hydrops (such as ascites or polyhydramnios) were present, or when there were very large lesions or lesions rapidly increasing in size. If there were multiple large cysts within the lesion, a single shunt was used, aiming to traverse several cysts.

Results: Shunts were inserted at a mean gestational age of 24.6 (range, 17-32) weeks. Marked mediastinal shift was present in all cases. Six fetuses were hydropic and, of the remaining five, one had severe polyhydramnios, three had lesions that were rapidly increasing in size and one had a very large lesion at initial presentation. In total, four cases had polyhydramnios. Shunting one cyst always decompressed the entire lesion and hydrops and/or polyhydramnios resolved in all surviving fetuses. One hydropic fetus that underwent the procedure at 17 weeks died 1 day later. The shunt dislodged in one case and the lesion did not re-expand. No mother went into labor or had ruptured membranes before 35.6 weeks. Mean gestational age at delivery was 38.2 weeks (n = 10). All pregnancies were delivered vaginally, with no maternal complications. All newborns had uneventful lobectomies, and pathology confirmed CCAM in all cases.

Conclusion: Fetal thoracoamniotic shunting for large macrocystic CCAM is associated with favorable outcome in most cases, and should be considered in severe cases even before hydrops develops.