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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 lymphoid tissue. But these
cancers are not lymphomas. Lymphomas start in the lymphoid tissue and
can then spread to other organs.
There are 2 main types of lymphomas.
- Hodgkin lymphoma (also known as Hodgkin's lymphoma, Hodgkin
disease, or Hodgkin's disease) is named after Dr. Thomas Hodgkin, who
first described it.
The cells of these 2 types of lymphoma look different under a
microscope. But in some cases, special lab tests may be needed to tell
them apart.
The information here refers to non-Hodgkin lymphoma (NHL) in
adults. Our other documents focus on non-Hodgkin
lymphoma in children, lymphomas of
the skin, and Hodgkin
disease.
The lymph system and lymphoid tissue
To better understand what lymphoma is, it helps to know
something about the body's lymph (pronounced "limf") 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 other organs that
are part of the body's immune and blood-forming system. These tissues
make some blood cells and protect against germs.
Lymphocytes
The main kind of cell found in lymphoid tissue is a type of
white blood cell called the lymphocyte.
There are 2 main types of lymphocytes: B cells and T cells. Most
lymphomas start in the B cells. There are also many sub-types and
stages of development of B and T cells. Normal T cells and B cells do
different jobs within the immune system. Knowing the exact cell type of
a lymphoma is the first step in deciding on a treatment.
Start and spread of non-Hodgkin lymphoma
Because lymphoid tissue is in many parts of the body,
lymphomas can start almost anywhere.
Types of non-Hodgkin lymphoma
Non-Hodgkin lymphomas (NHL) are often divided into types based
on how the cancer cells look under a microscope, certain features of
the lymphoma cells, and the presence of certain chemicals on the
surface of the cells. There are many different types of NHL. The
classification system is very complex and can be confusing, even for
many doctors.
The information below gives a very broad outline of 2 of the
most common types of NHL. Together, these 2 types account for about
half of all cases of NHL. But there are many more types. Your doctor
can give you more exact information about your type of NHL and what
that means for your treatment choices and chances for survival. You can
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 out of every 3
cases of lymphoma. The cells are large, and the cancer often grows
quickly. It can affect any age group but is mostly found in older
people. About half of all people who have this kind of lymphoma are
cured with treatment. Cure is most likely if the lymphoma was found in
only one part of the body (localized).
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. This is a slow-growing cancer. It is found most
often in older people and is rare in very young people. Although
standard treatment will not often cure this cancer, people may live a
long time with it. After 5 years, around 70% of people with this type
of cancer will still be alive. Over time, some follicular lymphomas
change into the fast-growing diffuse B-cell type.
Last Medical Review: 08/06/2009
Last Revised: 08/06/2009
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