[ Monash University ]

Museum of Pathology

BENIGN TERATOMA OF THE ANTERIOR MEDIASTINUM

BENIGN TERATOMA OF THE ANTERIOR MEDIASTINUM

Clinical History

This specimen was removed surgically from the anterior mediastinum.

Pathology

The specimen is of a multi-lobulated cyst 7 cm in largest diameter, which has been bisected, the inner and outer surfaces being displayed. The inner aspect shows a fibrous-walled cyst roughly divided into compartments by fibrous partitions, some of which are fenestrated. The inner lining is generally smooth and some lipid-like deposits are also present. Superiorly the wall shows several small cystic spaces. The outer wall of the cyst shows a white shiny capsule. Sub-capsular areas of haemorrhage are most likely due to operative trauma. Histologically this was a benign cystic teratoma lined by simple columnar respiratory epithelium and in parts by a more flattened epithelium. The wall contained thymic and salivary tissue.