About the lymphatic system
The lymphatic system is made up of thin tubes that branch out to all parts of the body. The lymph system carries lymph, a colorless fluid containing lymphocytes. Lymphocytes are a type of white blood cell that are part of our immune system and help fight germs in the body. B-lymphocytes, also called B cells, make antibodies to fight bacteria. T-lymphocytes, also called T cells, kill viruses and foreign cells and trigger the B cells to make antibodies.
Groups of tiny, bean-shaped organs called lymph nodes are located throughout the body at different sites in the lymphatic system. The largest areas of lymph nodes are found in the neck, chest, underarms, abdomen, pelvis and groin. Other parts of the lymphatic system include the spleen, which makes lymphocytes and filters the blood. The thymus is an organ under the breastbone. And the tonsils are located in the throat and the bone marrow, which are the spongy red tissue inside bones that makes white blood cells, which are cells that fight infection. Tonsils also make red blood cells, which carry oxygen throughout the body, and platelets, which are cells that help the blood to clot.
About non-Hodgkin lymphoma
Non-Hodgkin lymphoma (NHL) is a term that refers to a group of several, very different types of lymphoma. Lymphoma is a cancer of the lymphatic system. Lymphoma usually begins when healthy cells in the lymphatic system change and grow uncontrollably, which may form a tumor. Occasionally, lymphoma can also begin outside the lymph node system, called extranodal, especially in children.
Because lymph tissue is found in so many parts of the body, NHL can start almost anywhere and can spread to almost any organ in the body. It most often begins in the lymph nodes, liver, or spleen but can also involve the stomach, intestines, skin, thyroid gland, or any other part of the body.
This section covers NHL in children. Learn more about adult NHL.
Types of NHL in children
There are three major categories of NHL in children. The category is identified by how the cells look under a microscope.
Burkitt lymphoma. This type of B-cell lymphoma commonly affects the bone marrow and central nervous system, which means the brain and spinal cord. Burkitt lymphoma is one of the fastest growing types of cancer. It most often develops in the abdomen and may spread to other organs, including the brain. Burkitt lymphoma accounts for about 40% of NHL in children in the United States.
Large cell lymphoma (LCL). LCL, which accounts for about 25% of childhood NHL, may develop in the throat, abdomen, lymph tissue of the neck, or near the thymus. LCL is further classified into subtypes. The most common subtypes of LCL include large B-cell lymphoma (15%), which develops from B cells, and anaplastic large cell lymphoma (ALCL; 10%), which commonly develops from T cells but can arise rarely from B cells.
Lymphoblastic lymphoma (LBL). LBL accounts for about 30% of all childhood NHL. It most often develops in lymph nodes in the chest area (mediastinum) behind the breastbone (near the thymus gland) and can spread to the surface of the brain, the bone marrow, other lymph nodes, and the membranes surrounding the heart and lungs.
Looking for More of an Overview?
If you would like additional introductory information, explore these related items. Please note these links will take you to other sections on Cancer.Net:
ASCO Answers Fact Sheet: Read a one-page fact sheet (available as a PDF) that offers an easy-to-print introduction to this type of cancer.