Cite this page: Gulwani H. Anatomy. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/mediastinumgeneral.html. Accessed November 28th, 2023.
Definition / general
- Mediastinum is thoracic cavity between pleural cavities, from sternum to spine, thoracic inlet to diaphragm
- Symptomatic tumors are usually 2 - 3 cm or more; most masses are detected incidentally and undergo needle biopsy
- Superior mediastinum: thymomas, thymic cyst, lymphoma, thyroid lesions, parathyroid adenoma
- Anterior mediastinum: ventral to anterior cardiac border and aortic root - thymic epithelial tumors and cysts, germ cell neoplasms, lymphoproliferative lesions, retrosternal thyroid glandular proliferations, parathyroid lesions, aorticopulmonary type paragangliomas, lymphangioma, hemangioma, lipoma
- Middle mediastinum: between (a) anterior cardiac silhouette and aortic root and (b) posterior tracheal carinii - pericardial cyst, bronchogenic cyst, lymphoma
- Posterior mediastinum: dorsal to large conducting airways - neurogenic tumors: schwannoma, neurofibroma, ganglioneuroma, ganglioneuroblastoma, MPNST, neuroblastoma, paraganglioma, gastroenteric cysts
- Acquired hypogammaglobulinemia or pure anerythrogenesis: thymoma, leukemia, lymphoma
- Myasthenia gravis: thymic hyperplasia, thymoma
- Superior vena cava syndrome: usually indicates malignancy, most commonly metastatic lung carcinoma and lymphoma in adults and lymphoma and acute leukemia in children; also fibrous mediastinitis
- Systemic symptoms (weight loss, fever, night sweats): lymphoma, Castleman disease, microcystic anemia