Cavernous lymphangioma of fetal thigh

Abstract

A 35-year-old woman was referred to our institution at 19 weeks' gestation because a mass located at the right fetal thigh was noted, reporting with a 46,XX karyotype of cultured amniotic cells. Prenatal ultrasound examinations revealed a 73 mm 47 mm 35 mm irregular multiseptated cystic mass involving the whole right fetal thigh with no obvious blood flow visualized using color Doppler images (Fig. 1A and B). The remaining ultrasound images for the female fetus, placenta, and amniotic fluid were unremarkable. Given a tentative diagnosis of lymphangioma and uncertain postnatal prognosis regarding functional and aesthetic impairments after treatment, the patient made a decision to terminate the pregnancy. Postmortem photographs were compatible with the prenatal three-dimensional ultrasound images (Fig. 2A and B). The pathologic reports confirmed an isolated unencapsulated cavernous lymphangioma involving the dermis and subcutaneous layers and composed of multiple dilated thin-wall lymphatic vessels filled with proteinaceous fluid (Fig. 3). The primordial lymphatic formations, visible at 6e7 weeks of embryonic development, include two juguloaxillary lymphatic sacs, two lumboiliacal lymphatic sacs, the retroperitoneal lymphatic sac, and the chylocyst. Lymphangiomas are congenital malformations of the lymphatic systems due to either a sequestration of peripheral lymphatic tissue with no connection to the normal lymphatic system, a missing connection of primordial lymphatic sacs with the venous system, or the obstruction of lymphatic vessels [1]. Lymphangiomas may be superficial, subcutaneous, or deep enough to intertwine with muscles or organs. The nomenclature regarding lymphatic malformation is confusing. Lymphangiomas have been classified as capillary or cavernous. Capillary lymphangiomas are slightly elevated or