Lymph Nodes

Lymph nodes are small, bean-shaped components of the lymphatic system, and they play an essential role in the body's immune system. There are over five hundred lymph nodes in the body, each one usually no greater than one inch in length, and often much smaller. Clusters of lymph nodes are particularly congregated in the armpits, the neck, and groin area, and they can be felt under the skin in these areas (1, 2).

Lymph nodes act as filters for lymph fluid, trapping bacteria, viruses, and other foreign substances, and then destroying them with special white blood cells known as lymphocytes. Lymph nodes may become enlarged or swollen when they fight an infection due to the production of additional white blood cells, and it is for this reason that doctors check for swollen lymph nodes during routine examinations (1, 3).

The typical lymph node is encased by connective tissue referred to as a capsule. The node consists of lymph tissue within which there are compartments called lymph nodules. The nodules contain dense masses of lymphocytes, along with macrophages, which work along with lymphocytes to entrap and remove invading cells. Lymph vessels carry lymph into the lymph nodes, throughout the lymph tissue and into the nodules, where it is processed and cleansed before being carried away (1, 3).

Cancer can occur in the lymph nodes, and when the lymph nodes are the primary site it is known as lymphoma. Because cancer cells from a separate site can be carried by the lymphatic system into the lymph nodes, it is not uncommon for the lymph nodes to be the secondary site of a cancer (2). The determination of whether or not cancer has spread to the lymph nodes is an important part of staging for many types of cancer, including mesothelioma (4).

'Lymph Nodes' Sources:
  1. "Lymph Nodes." From Imaginis.com. Available: http://www.imaginis.com/breasthealth/lymph_nodes.asp (Accessed August 7, 2007).
  2. "Secondary cancer in the lymph nodes." From Cancerbackup.org. Available: http://www.cancerbackup.org.uk/Cancertype/Lymphnodessecondary/Secondarycancerinthelymphnodes (Accessed August 7, 2007).
  3. "Lymph Nodes." (2001) Stedman's Concise Medical Dictionary for the Health Professions, 4th ed. 
  4. "Mesothelioma Stages." From MesotheliomaWeb.com. Available: http://www.mesotheliomaweb.org/doctor-patient.htm (Accessed August 7, 2007).

 

 

 

 

 
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