Mature teratoma of the posterior mediastinum: report of a case.

Mediastinal teratoma generally arises in the anterior mediastinum. Posterior mediastinal teratomas have been rarely reported to date, especially in adults. We report a case of posterior mediastinal teratoma in a 57-year-old woman. The pre-operative diagnostic work-up revealed a posterior mediastinal tumor with calcification and fluid components. The tumor, adhering to the descending aorta, was radically removed through video-assisted thoracic surgery. Histological examination was concluded for a mature teratoma with cystic change. The imaging features of posterior mediastinal teratomas are identical to those in the anterior mediastinum, except for their location. To be different from anterior mediastinal teratomas, benign teratomas in the posterior mediastinum are often involved with a major surrounding structure, including aorta, chest wall, and esophagus. When a posterior mediastinal tumor has the typical features of a mature teratoma in the pre-operative findings, the adhesion to the surrounding structure should be considered.