What Are Mediastinal Tumors (Neoplasms)?

Neoplasms are abnormal growths of tissue. They can occur in almost any area of the body. They’re also called tumors and most often linked with cancer. Mediastinal tumors develop in the mediastinum. The mediastinum is the area in the middle of the chest that lies between the sternum (breastbone) and spinal column. The area contains vital organs including the heart, esophagus, and trachea.

Mediastinal tumors develop in one of three areas of the mediastinum: the anterior (front), the middle, or the posterior (back). The position of the tumor in the mediastinum typically depends on patient’s age.

Children are more likely to develop them in the back of the mediastinum. These are often benign, or noncancerous. Adults are more likely to develop them in the front of the mediastinum. These tumors are typically malignant, or cancerous. Affected adults are usually between the ages of 30 and 50. As a whole, mediastinal tumors are very rare.

There are a number of different types of mediastinal tumors. What causes these tumors depends on where they form in the mediastinum.

In the front of the mediastinum, tumors can be caused by:

  • lymphoma, including Hodgkin’s disease and non-Hodgkin’s lymphoma
  • thymoma and thymic cyst (a tumor of the thymus)
  • thyroid mass mediastinal (generally a benign growth, but it can sometimes be cancerous)

In the middle of the mediastinum, tumors can be caused by:

  • bronchogenic cyst (a benign growth that starts in the respiratory system)
  • lymphadenopathy mediastinal, or enlargement of the lymph nodes
  • pericardial cyst (a benign growth on the heart lining)
  • thyroid mass mediastinal
  • tracheal tumors (usually benign growths)
  • vascular complications, such as swelling of the aorta

In the back of the mediastinum, tumors can be caused by:

  • extramedullary haematopoiesis (rare growths that start in the bone marrow and are related to severe anemia)
  • lymphadenopathy mediastinal (enlarged lymph nodes)
  • neuroenteric cyst mediastinal (a rare growth involving both the nerves and the gastrointestinal system)
  • neurogenic neoplasm mediastinal (cancerous cells of the nerves)

Neurogenic neoplasm mediastinal is the most common cause of posterior mediastinal tumors. According to the Cleveland Clinic Foundation, about 70 percent of these are benign.

Tumors that form in the mediastinum are also known as primary tumors. Sometimes mediastinal tumors will develop because cancer from another part of the body has spread. The spread of cancer from one area of the body to another is known as metastasis. Mediastinal tumors that develop because of metastasis are known as a secondary tumor.

If you have a mediastinal tumor, you may not have any symptoms. Tumors are typically found during a chest X-ray that was ordered to diagnose another health condition.

If symptoms develop, it’s often because the tumor is pushing on surrounding organs. Symptoms can include:

  • cough
  • shortness of breath
  • chest pain
  • fever/chills
  • night sweats
  • coughing up blood
  • unexplained weight loss
  • swollen lymph nodes
  • respiratory blockage
  • hoarseness

If you have symptoms of a mediastinal tumor, your doctor will order additional tests to confirm your diagnosis. These tests may include:

  • a chest X-ray
  • a CT scan of the chest
  • an MRI of the chest
  • a mediastinoscopy with biopsy

Mediastinoscopy with biopsy is used to collect cells from the mediastinum. During this test, you’ll receive anesthesia. Then, your doctor will make a small incision under the breastbone. They’ll remove a sample of tissue and have it analyzed to see if cancer is present. This procedure will help your doctor accurately diagnose the type of tumor you have.

Treatment for mediastinal tumors will depend on their location and will be determined by your doctor. Surgery is often used first to remove the tumor. Once the tumor is removed, your doctor may use chemotherapy and/or radiation therapy to destroy remaining cancer cells.

Both benign and malignant tumors require treatment. As benign tumors grow, they’ll push against surrounding organs and tissues and can affect organ function. Cancerous tumors can spread to other areas of the body. Tumors that invade the heart or the vessels of the heart can lead to death.

Tumors may also invade the spinal column. This may result in spinal cord compression.

Treatment involving chemotherapy and radiation can have serious side effects, such as:

  • changes in appetite
  • bleeding problems
  • anemia
  • constipation
  • diarrhea
  • fatigue
  • hair loss
  • infection
  • nausea/vomiting
  • pain
  • swelling

Radiation may also cause changes in the skin, like:

  • dryness
  • itching
  • peeling
  • blistering

The outlook for patients with mediastinal tumors depends on the location of the tumor. Long-term outlook also depends on if the tumor is primary or secondary. Your doctor will tailor your treatment to your type of mediastinal tumor. Talk to your doctor to get more accurate information about your prognosis.