[Mediastinal localization of a growing teratoma syndrome: a case report].

The development of testicular germ cell tumors may be marked by a rare phenomenon: the growing teratoma syndrome. It consists of residual masses, usually retroperitoneal and, more rarely, thoracic, that appear during or after chemotherapy, although the tumor markers are normalized. We report a case of posterior mediastinal localization. This mediastinal localization is very rare, and because of the proximity to intercostal arteries, induces a risk of postoperative paraplegia.