Journal of Ultrasound in Medicine, Vol 14, Issue 12 927-936, Copyright © 1995 by American Institute of Ultrasound in Medicine
Fetal lung masses: prenatal course and outcome
B. Bromley, R. Parad, J. A. Estroff and B. R. Benacerraf
Department of Obstetrics and Gynecology, Massachusetts General Hospital, Boston, USA.
We describe 25 cases of echogenic or complex fetal lung masses seen
sonographically and suspected of being cystic adenomatoid malformations or
sequestrations of the lung. On the basis of prenatal sonographic
appearance, 40% of fetuses were suspected of having type 1, 20% type 2, and
40% type 3 cystic adenomatoid malformations or sequestrations. Sixteen
(64%) of the 25 fetuses with lung masses survived the perinatal period, and
80% of the nonaborted fetuses survived. Eleven infants (69% of liveborns)
had no respiratory symptoms at birth. Nine of the survivors underwent
surgical resections of their masses after birth, whereas the other seven
children are being followed conservatively. The postnatal diagnoses
revealed that four of the fetuses had sequestrations, one had a
sequestration with elements consistent with cystic adenomatoid
malformation, and two who were thought to have type 1 cystic adenomatoid
malformation had an esophageal duplication cyst and a thoracic
neuroblastoma, respectively. All the other infants who had a pathologic
diagnosis or postnatal imaging had cystic adenomatoid malformations.
Increasing mediastinal shift was associated with decreasing survival as 90%
of fetuses with no mediastinal shift are alive, whereas 50% of the
nonaborted fetuses with a severe mediastinal shift survived. Follow-up
scans in utero were available in 15 cases. The size of the mass became
smaller in 53% during gestation. Seventy-one percent of pregnancies had
normal amniotic fluid volumes and 29% were complicated by polyhydramnios.
Survival of nonaborted fetuses was 100% in pregnancies with normal amniotic
fluid compared with 50% in those with polyhydramnios. Eight percent of the
fetuses with chest masses had additional structural abnormalities and were
karyotypically abnormal. In conclusion, many fetuses with lung masses show
improvement of the sonographic findings in utero, and many infants may not
be symptomatic at birth. Of the survivors in this series, only slightly
greater than half underwent surgery.