Angiomyxoma of the umbilical cord in one twin with cystic degeneration of Wharton's jelly. A case report.

We report the prenatal diagnosis of an angiomyxoma of the umbilical cord in a female fetus of a dizygotic twin pregnancy. The pregnant woman was hospitalized at 18 weeks for exclusion of a suspected exomphalos. Using high-resolution ultrasound and color doppler, the umbilical tumor (8 x 5 x 4 cm) was suspected to be an angiomyxoma without malformations in the fetus. Neither chromosomal aberrations nor elevated alphafetoprotein were found after amniocentesis. Serial examinations showed an increase in the size of the cystic mass without deterioration of the fetal condition. Macroscopical and microscopical examinations of the tumor performed after delivery revealed an angiomyxoma with cystic degeneration of Wharton's jelly. Tumors of the umbilical cord are rare anomalies and should be considered when using prenatal ultrasound for detection of cystic lesions.