Prenatal diagnosis of giant cystic hygroma: prognosis, counselling, and management; case presentation and review of the recent literature.

Cystic hygromas have historically been associated with a grim prognosis when discovered during prenatal sonographic study of the fetus. This same grim prognosis is not observed by the paediatric surgeon who evaluates the neonate or paediatric patient. We present a fetal patient with a massive anterior cystic hygroma discovered in the third trimester prior to 30 weeks. This case and a review of the literature suggest tailoring the prognosis by category when counselling patients: (1) first trimester, normal karyotype--good; (2) first trimester, abnormal karyotype--poor; (3) second trimester and early third--poor to guarded; and (4) mid to late third trimester--good.