About Lymphoma

To go to the Leukemia and Lymphoma Society website, click here.

Some information on lymphoma, exerpted from their website:
"Lymphoma is the name for a group of blood cancers that develop in the lymphatic system. Hodgkin lymphoma and non-Hodgkin lymphoma (NHL) are the two main types of lymphoma. 

Lymphoma originates in the lymphatic system. The lymphatic system is part of the body's immune system, which is the body's defense against infection. The marrow and lymphocytes are part of the immune system. Some other parts of the immune system are the lymph nodes, the lymphatic vessels and the spleen.

Lymphoma starts with a change to a lymphocyte. The change to the lymphocyte causes it to become a lymphoma cell. The lymphoma cells pile up and form masses that gather in the lymph nodes or other parts of the lymphatic system.

In 2009, about 601,180 people are living with lymphoma or are in remission. This number includes about 148,460 people with Hodgkin lymphoma and about 452,720 people with non-Hodgkin lymphoma.

Hodgkin lymphoma has characteristics that distinguish it from other diseases classified as lymphoma, including the presence of Reed-Sternberg cells. These are large, malignant cell found in Hodgkin lymphoma tissues and named for the scientists who first identified them.

Non-Hodgkin lymphoma (NHL) represents a diverse group of diseases that are distinguished by the characteristics of the cancer cells associated with each disease type.


Causes and Risk Factors of Non-Hodgkin Lymphoma
The reasons for the development of NHL are not known. Immune suppression plays a role in certain cases.

People infected with the human immunodeficiency virus (HIV) have a higher risk of developing lymphoma. There is a higher incidence of NHL in farming communities. Studies suggest that specific ingredients in herbicides and pesticides such as organochlorine, organophosphate and phenoxyacid compounds are linked to lymphoma. The number of lymphoma cases caused by such exposures has not been determined.

Exposure to certain viruses and bacteria is associated with NHL. It is thought that infection with a virus or bacterium can lead to intense lymphoid cell proliferation, increasing the probability of a cancer-causing event in a cell. Some examples include

Epstein-Barr virus (EBV) infection—in patients from specific geographical regions—is strongly associated with African Burkitt lymphoma. The role of the virus is unclear since African Burkitt lymphoma also occurs among people who have not been infected with EBV. Epstein-Barr virus infection may play a role in the increased risk of NHL in persons whose immune systems are suppressed as a result of organ transplantation and its associated therapy.

Human T-lymphotropic virus (HTLV) is associated with a type of T-cell lymphoma in patients from certain geographic regions in Southern Japan, the Caribbean, South America and Africa.

The bacterium Helicobacter pylori causes ulcers in the stomach and is associated with the development of mucosa-associated lymphoid tissue (MALT) lymphoma in the stomach wall.

About a dozen inherited syndromes can predispose individuals to later development of NHL. These inherited disorders are uncommon, but the concept of predisposition genes is under study to determine if they play a role in the sporadic occurrence of NHL in otherwise healthy individuals.


Incidence
About 74,490 people living in the United States will be diagnosed with lymphoma in 2009 (8,510 cases of Hodgkin lymphoma and 65,980 cases of NHL).

The incidence of Hodgkin lymphoma is consistently lower than that of NHL. Incidence rates for Hodgkin lymphoma tend to be higher among males than among females.

NHL is more common in males than in females. NHL is the seventh most common cancer in males and females in the United States.

Lymphoma (Hodgkin lymphoma, 7.2 percent; NHL, 6.6 percent) is the third most common cancer in children. In 2009, children younger than 15 years will comprise more than 4.5 percent of all Hodgkin lymphoma cases expected to be diagnosed and 0.7 percent of all NHL cases expected to be diagnosed."