Prenatal diagnosis of a large axillary cystic lymphangioma by three-dimensional ultrasonography and magnetic resonance imaging

Cystic lymphangiomas are benign tumors of the lymphatic system, appearing as uniseptate or multiseptate cystic masses, often located in the area of the neck (75%) or the axilla (20%). Postnatal outcome depends mainly on the size and location of the lesion. An increasing number of such congenital abnormalities are detected on routine conventional prenatal ultrasonography. The absence of blood flow on color Doppler mapping is characteristic of lymphangiomas as opposed to hemangiomas. So far, prenatal evaluation for the prognosis of fetal lymphangiomas has been based solely on two-dimensional ultrasonography (2DUS). Magnetic resonance imaging (MRI) may help in assessing the extent of a lesion, as suggested in a recent case report of a fetal intra-abdominal lymphangioma. We report a case of prenatal assessment of axillary lymphangioma by three-dimensional ultrasonography (3DUS), and we analyze the information provided by this technique in comparison with MRI and 2DUS.