Which lymphatic system malformation presents as a multilocular anechoic cervical mass with a thin surrounding membrane and is associated with fetal hydrops?

Which lymphatic system malformation presents as a multilocular anechoic cervical mass with a thin surrounding membrane and is associated with fetal hydrops?

• A. Cystic hygroma
• B. Lymphangioma
• C. Teratoma
• D. Goiter

Answer: (A)

Cystic hygroma is a congenital lymphatic malformation that classically presents in the neck as a multiloculated, fluid-filled (anechoic) mass with thin walls separating the cystic spaces. The posterior cervical region is most common, and such lesions can extend into the axilla or mediastinum. When the lesion is large, it can obstruct lymphatic drainage and lead to hydrops fetalis, which explains its association with fetal hydropsis. The appearance—multiple small cystic compartments with delicate septations—fits this diagnosis precisely. Other neck masses don’t fit as well. Teratomas often show a mix of solid and cystic areas with possible calcifications or fat, and goiters tend to be midline thyroid tissue with vascularity rather than a multilocular purely cystic mass. Lymphangioma is a broader term, but the described imaging features and location point to the cystic hygroma specifically.

Cystic hygroma is a congenital lymphatic malformation that classically presents in the neck as a multiloculated, fluid-filled (anechoic) mass with thin walls separating the cystic spaces. The posterior cervical region is most common, and such lesions can extend into the axilla or mediastinum. When the lesion is large, it can obstruct lymphatic drainage and lead to hydrops fetalis, which explains its association with fetal hydropsis. The appearance—multiple small cystic compartments with delicate septations—fits this diagnosis precisely.

Other neck masses don’t fit as well. Teratomas often show a mix of solid and cystic areas with possible calcifications or fat, and goiters tend to be midline thyroid tissue with vascularity rather than a multilocular purely cystic mass. Lymphangioma is a broader term, but the described imaging features and location point to the cystic hygroma specifically.