Fetal mediastinal teratoma: a case report

Teratomas are the most common congenital tumors, and are composed of various tissues of ectodermal, mesodermal, and endodermal origin. Usually, they contain derivatives of all three germ layers such as bone, cartilage, muscle, epithelial and glandular tissue. Mediastinal teratomas are extremely rare, and usually arise in the anterior mediastinum as a median or paramedian mass. In the perinatal period, up to 15% of all teratomas are observed. The tumor is more often located in the anterior mediastinum, may be associated with the thymus or thyroid gland, in some cases it is not possible to determine a clear connection between the tumor and adjacent organs. Mediastinal teratoma can cause hydrops fetalis, which worsens the effects of the mass compression on the vital mediastinal organs. Diagnosis is usually made during routine pregnancy checkups by ultrasonography, and differential diagnosis with other mediastinal masses such as congenital cystic-adenomatous lung malformation, pulmonary sequestration, intrapericardial malformations is crucial. We report a new case of 34 year old woman’s pregnancy complicated by non-mature Grade 3 mediastinal teratoma of fetus, who therefore was diagnosed death on the 6th day postnatally.