Mediastinal lymph nodes are lymph nodes located in the mediastinum. The mediastinum is the area located between the lungs that contains the heart, esophagus, trachea, cardiac nerves, thymus gland, and lymph nodes of the central chest.

The enlargement of lymph nodes is referred to as lymphadenopathy.

Causes

Lymph nodes can become enlarged due to infections, cancer, and inflammatory diseases. There are many different causes of mediastinal lymphadenopathy. Conditions that cause inflammation in the chest area, can cause enlargement of the lymph nodes of the chest.

Examples include:

  • Acute lymphoblastic leukemia (ALL)
  • Anthracosis (“miner’s lung”)
  • Chronic obstructive pulmonary disease (COPD)
  • Coccidioidomycosis
  • Cystic fibrosis
  • Esophageal cancer
  • Histoplasmosis
  • Lung cancer
  • Lymphoma
  • Sarcoidosis
  • Tuberculosis (TB)

Diagnosis

Generally, mediastinal lymphadenopathy is diagnosed with imaging tests, such as chest ultrasound, chest CT, or chest MRI. These tests can provide a non-invasive assessment of the number and size of the lymph nodes. Sometimes the cause of lymph node enlargement might already be known due to the underlying medical conditions (such as TB or ALL).

From a global perspective, mediastinal lymphadenopathy is primarily associated with tuberculosis, which has a high rate of infection (10 million per year). In the United States, mediastinal lymphadenopathy is most commonly associated with lung cancer and COPD.

If the cause of the mediastinal lymphadenopathy is uncertain, your healthcare provider may order a biopsy so the tissue can be examined microscopically and the cause can be identified.

  • This can be obtained with a procedure known as mediastinoscopy. This involves a small surgical cut made just above the sternum or breastbone. A fiber-optic instrument called a mediastinoscope is then inserted through the incision and passed into the mid-part of the chest to obtain a sample of one or several lymph nodes. The procedure is performed in a hospital under general anesthesia.
  • A less invasive procedure, fine needle aspiration (FNA), is sometimes done to obtain a biopsy sample. During this procedure, a sample of cells is collected using endobronchial ultrasound guidance, in which a tube is inserted into the mouth and advanced down into the lungs.

The biopsy results are usually ready in five to seven days.

Investigating Cancer

Lymph nodes are small structures located in clusters throughout the body. They filter toxins and pathogens (infectious organisms).

When the mediastinal lymph nodes are enlarged due to a malignancy, lung cancer and lymphoma are the two most likely causes.

Mediastinal lymph nodes are typically the first ones where cancer cells from the lungs will travel, and this is why they can be examined to determine whether cancer is spreading. In some cases, mediastinal lymph node enlargement occurs due to secondary lung cancer when metastatic cancer spreads from another part of the body to the lungs—and then to the lymph nodes.

The location and number of lymph nodes involved is an important aspect of cancer staging. This classification system defines how advanced the malignancy is, and helps determine which treatments should be administered, and what outcomes can be expected.

Significance in Lymphoma

Lymphoma, a cancer of a type of white blood cells called lymphocytes, can be categorized as either Hodgkin lymphoma or non-Hodgkin lymphoma.

While chest imaging can identify suspicious-looking lymph nodes, a definitive diagnosis can only be made with a biopsy.

Mediastinal lymphadenopathy occurs in over 85% of Hodgkin lymphoma (HL) cases compared to only 45% with non-Hodgkin lymphoma (NHL). Moreover, the pattern of enlargement tends to be orderly and progressive with HL and more scattershot with NHL.

Frequently Asked Questions

  • What is mediastinal lymphadenopathy?
  • Mediastinal lymphadenopathy is the swelling of lymph nodes in the chest, specifically the mediastinum (the area between the lungs containing the heart, trachea, and esophagus). Mediastinal lymphadenopathy is a sign of an underlying disease or infection.
  • What are symptoms of mediastinal lymphadenopathy?
  • Because mediastinal lymph nodes are inside the chest cavity, they are usually only observed on imaging tests. With that said, enlarged lymph nodes can sometimes compress structures within the chest and cause coughing, shortness of breath, wheezing, and problems swallowing.
  • Learn More:
  • What Swollen Lymph Nodes in Armpits Mean
  • What causes mediastinal lymphadenopathy?
  • There are many causes of mediastinal lymphadenopathy, some of which involve the lung and others that affect the body as a whole.Some of the causes include:Acute lymphoblastic leukemia (ALL)Cancer metastasisCoccidioidomycosisChronic obstructive pulmonary disease (COPD)Cystic fibrosis (CF)Esophageal cancerHistoplasmosisHypersensitivity pneumonitisLung cancerLymphomaSarcoidosisTuberculosis (TB)
  • How is mediastinal lymphadenopathy diagnosed?
  • Diagnostic imaging of the lymph nodes with computed tomography (CT) or positron emission tomography (PET) can often identify mediastinal lymphadenopathy. If cancer is suspected, a biopsy can be used to evaluate the cells.
  • Learn More:
  • Facts About Lymph Nodes and Cancer
  • How is mediastinal lymphadenopathy treated?
  • Mediastinal lymphadenopathy may not be treated directly since it is ultimately the result of an underlying disease or infection. Treating the underlying cause will usually resolve the condition. However, with diseases like non-small cell lung cancer, the dissection (removal) of mediastinal lymph nodes is linked to improved survival times.
  • Learn More:
  • How Non-Small Cell Lung Cancer Is Treated

Mediastinal lymphadenopathy is the swelling of lymph nodes in the chest, specifically the mediastinum (the area between the lungs containing the heart, trachea, and esophagus). Mediastinal lymphadenopathy is a sign of an underlying disease or infection.

Because mediastinal lymph nodes are inside the chest cavity, they are usually only observed on imaging tests. With that said, enlarged lymph nodes can sometimes compress structures within the chest and cause coughing, shortness of breath, wheezing, and problems swallowing.

There are many causes of mediastinal lymphadenopathy, some of which involve the lung and others that affect the body as a whole.

Diagnostic imaging of the lymph nodes with computed tomography (CT) or positron emission tomography (PET) can often identify mediastinal lymphadenopathy. If cancer is suspected, a biopsy can be used to evaluate the cells.

Mediastinal lymphadenopathy may not be treated directly since it is ultimately the result of an underlying disease or infection. Treating the underlying cause will usually resolve the condition. However, with diseases like non-small cell lung cancer, the dissection (removal) of mediastinal lymph nodes is linked to improved survival times.