Hygroma or teratoma?: Pitfalls in the management of congenital cystic neck masses

SummaryThe differential diagnosis of a cervical mass detected antenatally or postnatally includes cystic hygroma and very rarely, teratoma. Even with present day high resolution imaging techniques, including MRI, a teratoma may be indistinguishable from a cystic hygroma radiologically. We present two cases of cervical teratoma. Experience with the first case, initially diagnosed and treated as cystic hygroma on MRI appearance, led to early suspicion and diagnosis of teratoma in the second case. Clinicians are now treating selected cases of cystic hygroma in utero with injection sclerotherapy on radiological grounds alone. From our experience we feel it important to highlight this pitfall in diagnosis and urge doctors to consider teratoma, albeit extremely rare, in the differential diagnosis.