Giant hemangioma of the fetal neck, mimicking a teratoma

Abstract

We present a case involving a giant hemangioma of the fetal neck, prenatal diagnosis of which was a teratoma. A 32-year-old pregnant woman was referred to our hospital at 31 weeks' gestation owing to a giant solid mass of the fetal neck and excessive amniotic fluid. The mass seemed to be occupying the neck almost entirely, extending to the nasopharyngeal cavity, the mandible, the surface of the left orbit and the left shoulder. Based on sonographic and magnetic resonance imaging (MRI) findings, diagnosis of a giant teratoma was made. Cesarean section was performed at 35.5 weeks' gestation, and a female infant weighing 2826 g was delivered. Purpurae were observed on the neck of the infant, and the tumor turned out to be a hemangioma. Postnatal MRI findings, in which the tumor's signal intensity differed from that of the prenatal findings, were quite compatible with the diagnosis of a typical hemangioma. Laser and corticosteroid treatment successfully decreased the volume of the mass. Although it may not always be possible to make a prenatal differential diagnosis between a hemangioma and a teratoma in the neck of the fetus, serial ultrasound and MRI examination are mandatory to evaluate the prognosis and to plan suitable treatment. Moreover, possible postnatal changes to the tumor characteristics have to be taken into consideration when evaluating the findings of prenatal diagnostic imaging.

Sonographic Features of Rare Posterior Fetal Neck Masses of Vascular Origin

“…In this series, all of these posterior masses were vascular in origin, and most were pathologically proven hemangiomas. There have been isolated case reports of giant hemangiomas; however in our series, several masses were smaller than 20 mL in volume 7 , 8 . Importantly, despite the presence of calcifications, which were previously thought to be virtually diagnostic of teratoma, 2 5 posterior neck masses containing calcifications were diagnosed as hemangiomas rather than teratomas.…”

“…They typically show color Doppler flow 7 , 8 . Although calcifications have been reported in hemangiomas, 13 other case reports did not describe their presence 7 , 8 . In this series, all of the confirmed hemangiomas except 2 contained calcifications.…”

“…They may be solid or mixed cystic and solid lesions 8 , 12 , 13 . They typically show color Doppler flow 7 , 8 . Although calcifications have been reported in hemangiomas, 13 other case reports did not describe their presence 7 , 8 .…”

“…Hemangiomas are benign lesions composed of proliferative and hyperplastic vascular endothelium 12 . They may be solid or mixed cystic and solid lesions 8 , 12 , 13 . They typically show color Doppler flow 7 , 8 .…”

“…Fetal neck masses can also complicate vaginal delivery as well as cause respiratory distress in the neonate and subsequent difficulty maintaining the airway 5 . Cervical teratomas and hemangiomas may result in high‐output cardiac failure in the infant 7 , 8 . Therefore, after the in utero detection of a neck abnormality, narrowing the differential diagnosis, although potentially a difficult task, is crucial.…”