Lymph nodes (also called lymph glands) are small oval structures scattered all over the body. Lymph nodes contain lymph cells (called lymphocytes). Lymphocytes grow and mature inside a lymph node.
These cells are a type of white blood cell (WBC) that helps the body fight infections. Lymph nodes are a part of the lymphatic system of the body. (See the article on the lymph system.)
Lymph nodes are connected to each other by lymph channels called the lymphatics—small tubes (like blood vessels)—through which lymph nodes as well as proteins and other substances move from one part of the body to another.
Lymph nodes in different parts of the body are named differently.
- Cervical lymph nodes—lymph nodes in the neck
- Axillary lymph nodes—lymph nodes in the armpits
- Mediastinal lymph nodes—nodes inside the chest
- Inguinal lymph nodes—those in the groyne
- Retroperitoneal and Mesenteric lymph nodes are lymph nodes in different parts of the abdomen.
- Pelvic lymph nodes are nodes located in the pelvis.
When lymph nodes increase in size, they are called enlarged lymph nodes. When enlarged nodes can be felt by the doctor (in areas like the neck, armpits, and groin), they are called palpable lymph nodes.
Lymph nodes can increase in size in a number of conditions.
Infections, cancer, and many immune diseases can affect lymph cells and cause an enlargement of lymph nodes. Enlarged lymph nodes are often the first sign of lymphoma, a cancer of lymph cells. But all enlarged nodes are not lymphoma. (See the article, Are Enlarged Lymph Nodes Always a Lymphoma?). Any enlarged node should be brought to the attention of a physician and investigated for the correct diagnosis.
Enlarged Lymph Nodes
Enlargement of lymph nodes is the most common warning sign of lymphoma.
Most individuals with lymphoma have no other symptoms. But what do enlarged lymph nodes really mean? Does an increase in the size of lymph nodes automatically indicate lymphoma?
Lymph node enlargement is not limited to lymphoma at all. In fact, there are several more common reasons for lymph node enlargement than lymphoma.
The most common cause of enlarged lymph nodes is infection. As lymph nodes are a part of the immune system that fights infections in the body, the presence of infection often causes lymph nodes to increase in size. All kinds of infections can cause node enlargement.
As infections are far more common than cancers, enlarged nodes in the neck or groyne are more often a sign of infection than cancer. Learn more about the lymph system.
Some other immune diseases like sarcoidosis or lupus can also cause lymph node enlargement all over the body.
Some medicines and allergies can occasionally cause enlarged nodes.
Cancers other than lymphoma are also a common cause of lymph node enlargement. Throat cancer, oral cancer, and cancers of the lung or breast often spread to nodes in the neck. Breast or lung cancer can spread to nodes in the armpits. Uterine cancer, ovarian cancer, rectal cancer, and anal cancer can spread to the lymph nodes in the groin. Leukemia can also cause enlarged nodes in different parts of the body.
Children with some diseases that affect the body’s metabolism (called storage diseases) can have enlarged nodes.
Thus, lymphoma is only one of the many possible causes of enlarged lymph nodes. A doctor will test you for many of these diseases before calling your enlarged lymph node a lymphoma.
A lymph node biopsy is the best test to determine whether a lymph node has lymphoma is a lymph node biopsy.
If the lymph node tests positive for lymphoma, special tests may be carried out on the biopsy material to determine exactly which type of lymphoma it is, using the molecular markers for lymphoma.
Understanding the Lymph System
Traversing your entire body like your blood vessels is another network of thin tubes carrying a fluid called lymph. You cannot see these tubes like you can spot the veins on your hand. But they travel with the blood vessels, carrying nutrients from your food and white blood cells all over your body.
What does it do?
The lymphatics are vitally important. Lymph carries white blood cells—a vital component of the immune system that protects the body from infections.
Whenever your body is attacked by infections, white blood cells reach the infected site fast. Then, using the lymphatics, other white cells are called to this area, and together a host of cells work together to control the infection.
Other Parts of the Lymph System:
The bone marrow is a kind of spongy tissue that is found within bones. Its function is to produce the white cells that fight infections.
The spleen is another critical component. It lies within the abdomen near the stomach. It is the finishing school and service garage for the white blood cells. White blood cells grow and mature in the spleen.
The thymus is another organ where white blood cells grow and multiply. It is located in the chest.
Where does Lymphoma Attack?
The lymph nodes are the most common sites where lymphoma manifests.
But it can affect any of the parts of the lymph system at various stages of the disease. In fact, as lymph vessels pass through virtually all the organs of the body, lymphoma can affect organs which are not normally part of this system.