What Is Non-Hodgkin Lymphoma in Children?

Cancer starts when cells in the body begin to grow out of control. Cells in nearly any part of the body can become cancer, and can spread to other areas of the body. To learn more about how cancers start and spread, see What Is Cancer?

Lymphoma is a type of cancer that starts in cells called lymphocytes, which are part of the body’s immune system.

Types of lymphoma

The 2 main kinds of lymphomas are:

  • Hodgkin lymphoma (also known as Hodgkin disease), which is named after Dr.Thomas Hodgkin, who first described it
  • Non-Hodgkin lymphoma (NHL)

These types of lymphomas differ in how they behave, spread, and respond to treatment, so knowing which type your child has is important.

Both of these types are more common in adults, but they can also occur in children and teens: NHL tends to occur in younger children, while Hodgkin lymphoma is more likely to affect older children and teens.

Hodgkin lymphoma is very similar in adults and children, and treatment is the same for both. For more information on this disease, see Hodgkin Lymphoma.

The lymph (lymphatic) system

The lymph system is part of the body’s immune system, which helps fight infections and some other diseases. It also helps fluids move around in the body.


The lymph system is made up mainly of cells called lymphocytes, a type of white blood cell. The main types of lymphocytes are:.

  • B lymphocytes (B cells): B cells normally help protect the body against germs (bacteria or viruses) by making proteins called antibodies. The antibodies attach to the germs, marking them for destruction by other parts of the immune system.
  • T lymphocytes (T cells): There are several types of T cells, each with a special job. Some T cells destroy germs or abnormal cells in the body. Other T cells help boost or slow the activity of other immune system cells.

Both types of lymphocytes can develop into lymphoma cells.

Different types of NHL can develop in children. Treatment depends on which type of NHL it is, so determining the exact type a child has is important.

Parts of the lymph system

The lymph system is in many parts of the body, so lymphomas can start almost anywhere. (This can affect what symptoms a child has.)

Lymph tissue is found in:

Lymph nodes: Lymph nodes are bean-sized collections of lymphocytes and other immune cells throughout the body. They can sometimes be felt under the skin in the neck, under the arms, and in the groin. Lymph nodes are connected to each other by a system of lymphatic vessels.

Lymph nodes get bigger when they fight infection. Lymph nodes that grow because of infection are called reactive nodes or hyperplastic nodes and are often painful when they are touched. An enlarged lymph node in a child is not usually a sign of a serious problem. Lymph nodes in the neck are often enlarged in children with sore throats or colds. But a large lymph node is also the most common sign of lymphoma. This is discussed more in Signs and Symptoms of Non-Hodgkin Lymphoma in Children.

Spleen: The spleen is an organ under the lower ribs on the left side of the body. The spleen makes lymphocytes and other immune system cells. It also stores healthy blood cells and filters out damaged blood cells, bacteria, and cell waste.

Bone marrow: The bone marrow is the spongy tissue inside certain bones, which is where new blood cells (including some lymphocytes) are made.

Thymus: The thymus is a small organ behind the upper part of the breast bone and in front of the heart. It's important in the development of T lymphocytes.

Adenoids and tonsils: These are collections of lymph tissue in the back of the throat. They help make antibodies against germs that are breathed in or swallowed. They are easy to see when they become enlarged during an infection, which occurs often in children, or if a lymphoma develops.

Digestive tract: Lymph tissue is also in the stomach and intestines, as well as many other organs.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.


Last Revised: August 1, 2017

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