Mediastinal Masses: Symptoms, Diagnosis & Treatments | MedStar Health

The mediastinum is an area in the chest that lies between the two lungs and between the sternum (breastbone) and the spine. This region contains and protects vital organs, which include the esophagus, the aorta, the heart, the trachea, and the thymus.

When an abnormal growth develops in the mediastinum, this is referred to as a mediastinal mass. These growths can be benign (non-cancerous) or malignant (cancerous). The masses are considered rare but can occur in patients of all ages.


Many individuals who have a mediastinal mass do not experience symptoms. In fact, most of these masses are discovered when individuals are undergoing imaging studies for another health complication. When an individual does have symptoms related to a mediastinal mass, they may experience:

  • Shortness of breath

  • Chest pain

  • A cough and/or coughing up blood

  • Night sweats

  • Unexplained weight loss

  • Hoarseness or a change in the voice

  • Noisy breathing

Additionally, due to their location, they can cause serious health complications and/or damage to nearby organs and structures if left untreated. Complications that can develop include:

  • Compression of the spinal cord

  • Invasion of the heart

  • Invasion of the tissue surrounding the heart (also called pericardium)

  • Invasion of the major blood vessels, aorta, and vena cava

  • Difficulty breathing

  • Low blood pressure


Mediastinal masses can develop due to a large number of reasons that are specific to the area in which the mass forms.

The masses that form in the anterior (front) mediastinum may develop due to:

  • Lymphoma (cancer of the lymph nodes)

  • Thymoma (a tumor of the thymus gland)

  • A thyroid mass (an abnormal growth of the thyroid)

The masses that form in the middle mediastinum may develop due to:

  • Pericardial cysts (cysts that develop in the pericardium, the tissue that surrounds the heart, and are present at birth)

  • Lymphadenopathy (a condition that results in enlargement of the lymph nodes)

  • Tracheal tumors (a tumor that forms in the trachea)

  • Thyroid masses (abnormal growths of the thyroid)

The masses that form in the posterior (back) mediastinum may develop due to:

  • Lymphadenopathy (a condition that results in enlargement of the lymph nodes)

  • Neurogenic neoplasms (abnormal growths that develop in the thoracic spine)

  • Extramedullary hematopoiesis (an accumulation of cells typically found inside the bone marrow in the mediastinum)

What to expect at your appointment

During your appointment, your doctor will ask you to provide a detailed medical history as well as an explanation of your symptoms. In order to make a diagnosis, your doctor will most likely want to perform imaging studies, such as an X-ray, an MRI scan, or a CT scan of the chest.

For a more accurate diagnosis, a biopsy of the tissue may be required. A procedure called a mediastinoscopy is a minimally invasive procedure that allows your doctor to see inside of the chest cavity and collect a small sample of the mass.

Non-surgical treatments

The recommended treatment for mediastinal masses will depend on the location of the mass, as well as the size of the growth and the severity of symptoms. Oftentimes, surgery is performed to remove the mass, even if it is benign. This is because even benign masses can push or impede surrounding organs and cause health complications. Individuals diagnosed with a malignant, or cancerous, mediastinal mass may also undergo radiation or chemotherapy in order to lower the risk of cancer recurrence.

Surgical treatment for mediastinal masses and post-treatment

If surgical resection of the mass is required, this can be performed using one of the following techniques:

  • Video-assisted thoracoscopy surgery (VATS): VATS is a minimally invasive procedure that utilizes one small incision and special instruments to access the chest region

  • Thoracotomy: An open surgical procedure that allows the surgeon to access the chest region using one long incision in the chest between the ribs

After surgical resection of a mediastinal mass, patients may be required to remain in the recovery unit to be monitored. Recovery time will depend on the type of surgery performed as well as the complexity of the surgery. It is important to follow all post-procedure instructions given to you by the surgeon in order to ensure a safe and quick recovery.

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