Enhancing mediastinal mass at MR: Castleman disease.

We report a case of an enhancing middle mediastinal mass imaged by MR and CT. Repeated nondiagnostic biopsies in this 25-yr-old male patient had resulted in profuse hemorrhage. Final pathological diagnosis after thoracotomy and debulking was Castleman disease. This is a rare, benign lymphoproliferative disorder of uncertain etiology. Histological varieties include the hyaline vascular type (80-90%) and the plasma cell type (10-20%). Cure is generally accomplished via surgical excision. This entity should be included in the differential diagnosis of enhancing mediastinal lesions, prompting awareness of the potential for bleeding complications following biopsy.