What is Mediastinum? What are the diseases?

Thymoma:  It is a tumor originating from epithelial cells of the thymus. It is the most common cause of primary mediastinal tumors and anterior mediastinal masses in adults.

Thymic carcinoma:  Thymic carcinomas are a heterogeneous group of epithelial tumors with early local invasion and distant metastasis potential.

Thymic Carcinoid:  Thymic carcinoid is a rare, aggressive tumor that typically affects men in the 4th and 5th decades (40-50 years) with neuroendocrine features.

Lymphoma:  Lymphoma accounts for 10-20% of all mediastinal tumors in adults and is the second most common cause of primary anterior mediastinal masses after thymoma.

Germ cell tumors:  They constitute 15% of anterior mediastinal tumors in adults and 24% in children. They can rarely be found in the posterior mediastinum.

Thyroid and parathyroid tissue: Intrathoracic thyroid tissue is usually an extension of a cervical goiter but may rarely be found ectopically in the mediastinum. Intrathoracic goiter are cervico-thoracic masses that compress the trachea, usually on the right side. Radiologically, it contains lobulated, sharp-edged, cystic and hemorrhagic changes and areas of calcification. Patients may develop symptoms such as shortness of breath, stridor, wheezing, and dysphagia.

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lymphadenopathy:  Infectious (mycobacterial and fungal) and non-infectious granulomatous diseases (such as sarcoidosis and silicosis) may involve mediastinal lymph nodes.

Vascular lesions:  They constitute approximately 10% of all mediastinal masses and arise from arteries or veins of the systemic or pulmonary circulation.

Neurogenic tumors:   Mediastinal tumors are usually located in the paravertebral area and neurogenic tumors are examined in three groups according to the structure they develop as peripheral nerve, sympathetic ganglion and paraganglion tumors.

Mediastinal Cystic Lesions:  Primary cysts of the mediastinum constitute 20% of all mediastinal lesions. This heterogeneous group includes pericardial cysts, bronchogenic cysts, enteric cysts, thymic cysts, and ductus thoracic cysts (43-47). Bronchogenic and enteric cysts are known together as enterogenic cysts.

Mediastinitis:  The term mediastinitis is used to express various infectious or inflammatory conditions in the mediastinum. Acute mediastinitis develops due to reasons such as esophageal or tracheobronchial perforation, penetrating chest trauma, postoperative sternal wound healing, paravertebral abscess or spread of oropharyngeal infection, RT, malignancy. Patients usually have a sudden onset of high fever, sweating, chest pain, dyspnea, and dysphagia.

Pneumomediastinum:  It occurs spontaneously or as a result of overstretching and rupture of the alveoli due to increased intrathoracic volume or pressure in conditions such as asthma, trauma, and mechanical ventilation.