Number of lymph nodes in human body

How Do They Work?

Your lymph nodes are connected to one another by lymph vessels (tubes that run through your body like veins). They carry lymph fluid -- a clear, watery liquid that passes through the nodes.

As the fluid flows through, cells called lymphocytes help protect you from harmful germs.

There are two kinds of lymphocytes -- B-lymphocytes (or B-cells) and T-lymphocytes (or T-cells).

• B-cells make antibodies that attach to germs and let your immune system know they need to be killed off.
• T-cells have a couple of jobs. Some destroy germs, while others keep track of immune cells. They let your body know when to make more of certain kinds and less of others. Memory T cells are T-cells that remain dormant after an infection and become active again when they are faced with the same infection.

Lymph fluid also carries protein, waste, cellular debris (what’s left after a cell dies), bacteria, viruses, and excess fat that are filtered by the lymphatic system before it’s dumped back into the bloodstream.

Swollen Lymph Nodes

When there’s a problem in your body, like an illness or an infection, your lymph nodes can swell. (This usually happens only in one area at a time.) It’s a sign that more lymphocytes are in action than usual, trying to kill off germs.

You may notice this most often in the glands in your neck. That’s why your doctor feels the area under your jawbone. They’re checking to see if those glands are bigger than usual or tender.

Many things can make your lymph nodes swell. Any infection can trigger it, including a cold or the flu, an ear infection, STDs (usually inguinal), shingles, tuberculosis, or an abscessed tooth. Rarely a vaccine can cause swollen lymph nodes on the side of the vaccination.  Much less often, it can be a sign of something more serious, like cancer.

Sometimes medicines like phenytoin (taken for seizures), or drugs that prevent malaria can cause swollen lymph nodes, too.

Lymph nodes (or lymph glands) are small lumps of tissue that contain white blood cells, which fight infection. They are part of the body’s immune system and filter lymph fluid, which is composed of fluid and waste products from body tissues. They help fight infections, and also play an important role in cancer diagnosis, treatment and the chance of recovery or recurrence.

Lymph nodes are located throughout the body, including the neck, armpits, groin, around the gut, and between the lungs. Lymph nodes drain lymph fluid from nearby organs or areas of the body.

How do lymph nodes filter lymph fluid?

Lymph fluid is carried to the lymph nodes by lymphatic vessels. The 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 the blood circulation.

If you have an infection or cancer, a lymph node may become swollen. If you are concerned about your lymph nodes, speak to your doctor.

Lymph nodes are located throughout the body. They drain lymph fluid from nearby organs or areas of the body.

How are lymph nodes and cancer related?

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.

Having swollen lymph nodes is only very rarely a sign of cancer. Lymph nodes may be swollen due to infection or inflammation. Swollen lymph nodes may be in the neck, under the arm or anywhere else there are lymph nodes. They can swell up to several centimetres and may stay swollen for weeks after the infection has cleared up.

Where are the 4 main locations of lymph nodes in the body?

What are the 7 lymph nodes?

What are the 6 lymph nodes?

What are the 5 lymph nodes?