[Clinicopathologic features of fetal nuchal cystic hygroma: report of 40 cases].

OBJECTIVE:To study the pathogenesis, pathologic features and prognosis of fetal nuchal cystic hygroma. METHODS:Forty autopsied cases of fetal nuchal cystic hygroma were collected during January 2003 to December 2012. The clinical history, pathologic changes and immunohistochemical (EnVision method) findings were reviewed, and the pathogenesis and pathologic characteristics were analyzed. RESULTS:Of the 40 cases, 16 (40.0%) showed single malformation and 24 (60.0%) were associated with multiple malformations in other organs and/or systems.Nineteen cases were septated and 21 were not. The associated malformations occurred in the respiratory system, skeletal system and urinary system.In the cases of combined malformations of umbilical cord, 3 were single umbilical artery malformations and 1 was torsion and stricture of umbilical cord.Four cases had chromosomal analysis, and all were trisomy-21. CONCLUSIONS:Fetal nuchal cystic hygroma is a rare disease. The etiology is unknown, but it is not neoplastic.Lymphangioma is divided into 3 types:capillary lymphangioma, cavernous lymphangioma and cystic hygroma according to their expansile growth pattern. The overall prognosis is determined by any co-existing chromosomal anomalies, associated malformations and the time of diagnosis of the cystic hygroma.