Prenatal sonographic diagnosis of axillary cystic lymphangiomas.

Cystic lymphangiomas are congenital malformations of the lymphatic system that occur most commonly in the nuchal region. Nuchal lymphangiomas are often referred to as cystic hygromas. Few cases of axillary cystic lymphangioma have been reported, but the prognosis of this lesion appears to be less grave than that of its nuchal counterpart. We present 2 cases of axillary cystic lymphangiomas that were diagnosed on prenatal sonography. In 1 case, prenatal sonography showed a multilocular, large cystic mass on the fetal left side, in the area of the lower chest and upper abdomen. The mass extended from at least the level of the umbilicus up to the neck but did not involve the neck. In the second case, prenatal sonography showed a multilocular, septate axillary cystic lymphangioma external to the chest with no flow on Doppler sonography. Follow-up sonography revealed normal fetal growth and enlargement of the cystic mass surrounding the left humerus. Both infants were delivered without complications and have been managed conservatively.