What is non-Hodgkin lymphoma?
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?
Non-Hodgkin lymphoma (also called non-Hodgkin's lymphoma, NHL, or just lymphoma) is cancer that starts in cells called lymphocytes, which are part of the body's immune system. Lymphocytes are in the lymph nodes and other lymphoid tissues (such as the spleen and bone marrow). Other types of cancer (lung or colon cancers, for example), can start in other organs and then spread to lymph nodes or other lymphoid tissue. But these cancers are not lymphomas. Lymphomas start in the lymphoid tissue and can then spread to other organs.
The main types of lymphomas are:
- Hodgkin lymphoma (also known as Hodgkin's lymphoma, Hodgkin disease, or Hodgkin's disease) is named after Dr. Thomas Hodgkin, who first described it.
- Non-Hodgkin lymphoma (NHL)
Different types of lymphomas behave, spread, and respond to treatment differently.
The rest of this document is only about non-Hodgkin lymphoma in adults.
The lymph system and lymphoid tissue
To better understand what lymphoma is, it helps to know something about the body's lymph system. The lymph system is made up of lymphoid tissue (found in many places in the body), lymph vessels, and a clear fluid called lymph.
Lymphoid tissue includes the lymph nodes and collections of lymphocytes in other organs (like the intestines), the spleen, and bone marrow.
The main kind of cell found in lymphoid tissue is a type of white blood cell called the lymphocyte. The main types of lymphocytes are: B cells and T cells. Normal B cells and T cells do different jobs within the immune system.
B lymphocytes: B cells help protect the body against germs by making proteins called antibodies. The antibodies attach to the germs and attract other immune system cells that surround and digest the germs. Antibodies also attract certain blood proteins that can kill bacteria. Most lymphomas start in the B cells.
T lymphocytes: There are several types of T cells and each has a special job. Some T cells help destroy cells infected with germs. Other types of T cells help boost or slow the work of other immune system cells.
Different types of lymphoma can develop from these different types of lymphocytes. The different types of lymphoma are treated differently, so finding out the exact type of lymphoma is important.
Start and spread of NHL
Because lymphoid tissue is found in many parts of the body, lymphomas can start almost anywhere.
Types of NHL
About half of all cases of NHL are one of the 2 types listed below, but there are also many other types. Ask your doctor for information about your type of NHL and what that means for your treatment choices and chances for survival. You can also find more detailed information about many of the other types in our separate detailed guide, Non-Hodgkin Lymphoma.
Diffuse large B-cell lymphoma: This kind makes up about 1 of every 3 cases of lymphoma. It can affect any age group but is mostly found in older people. This kind of lymphoma grows quickly, but often responds well to treatment.
Follicular lymphoma: About 1 out of 5 cases of lymphoma in the United States are of this type. The cells tend to grow in a circular pattern in the lymph nodes. Follicular lymphoma is found most often in older people and is rare in very young people. It tends to grow slowly. These lymphomas often don’t need treatment when they are first found. Instead, treatment might be delayed until the lymphoma is causing problems. Although standard treatment will not often cure this cancer, people may live many years with it. Over time, some follicular lymphomas change into a fast-growing diffuse B-cell type.
Last Medical Review: 08/27/2014
Last Revised: 01/22/2016