Cervical cystic hygroma in the fetus: clinical spectrum and outcome.

Cervical cystic hygroma is thought by most pediatric surgeons to be an isolated, usually resectable lesion with an excellent prognosis. However, prenatal sonography has revealed a high "hidden mortality" among fetuses with this condition, and most perinatologists consider it to be uniformly fatal. In an attempt to resolve these two differing perspectives, we analyzed 29 cases seen at two centers over 4 years. Of 27 fetuses diagnosed before 30 weeks' gestation, only one survived. Twenty-five of the 27 were aborted; severe hydrops was present in 21 of these 25. Two of the 27, both with stigmata of Noonan's syndrome, underwent spontaneous regression during the second trimester: one died at 2 weeks of age, and the other survived. Successful karyotypes were obtained on 17 fetuses: nine were normal, seven were 45X, and one was trisomy 21. Fetuses with abnormal karyotypes had a lower incidence of polyhydramnios (0% v 67%), additional anomalies (12% v 67%), and consanguinity or a history of abnormal pregnancies (0% v 89%). Two fetuses were diagnosed after 30 weeks' gestation. Neither had hydrops, polyhydramnios, associated anomalies, or an abnormal karyotype. One had a completely normal sonogram at 17 weeks' gestation. Both were operated on within the first 4 days of life; one did well without complications, and the other required a permanent tracheostomy because of extensive hypopharyngeal involvement. A cystic hygroma presenting in the fetus has a different natural history and prognosis from one presenting postnatally. The vast majority of fetal cases are diagnosed before 30 weeks' gestation, and present with hydrops or diffuse lymphangiomatosis. The dismal outlook in this group justifies elective termination in most cases.(ABSTRACT TRUNCATED AT 250 WORDS)