A small bean-shaped structure that is part of the body’s immune system. Lymph nodes filter substances that travel through the lymphatic fluid, and they contain lymphocytes (white blood cells) that help the body fight infection and disease. There are hundreds of lymph nodes found throughout the body. They are connected to one another by lymph vessels. Clusters of lymph nodes are found in the neck, axilla (underarm), chest, abdomen, and groin. For example, there are about 20-40 lymph nodes in the axilla. Also called lymph gland.
Location of lymph nodes
Lymph nodes are located throughout your body, including your neck, armpits, groin, around your gut, and between your lungs. Lymph nodes drain lymph fluid from nearby organs or areas of your body.
How lymph nodes filter lymph fluid
Lymph fluid is carried to your lymph nodes by lymphatic vessels. Your lymph nodes filter out harmful substances and waste products. They also contain immune cells called lymphocytes that destroy cancer cells and bacteria. The filtered fluid is then returned to your blood circulation.
Lymph nodes and cancer
Sometimes cancer can start in the lymph nodes (such as in lymphoma), but some others types of cancer can also spread from one part of the body to another through lymph nodes.
If a person has cancer, doctors examine lymph nodes carefully to see whether or not they are affected by cancer. They can do this by:
- feeling all the nodes in the body
- getting scans, for example a CT scan
- removing nodes near the cancer, then examining them under a microscope
- taking a biopsy of the lymph nodes near the cancer, then examining them under a microscope
- This is done to see if the cancer has spread or not. This helps doctors work out the best treatment for the cancer.
Also see immune system