Adult T-Cell Leukemia/Lymphoma
What is Lymphoma?
Lymphoma is a cancer of the white blood cells, namely
lymphocytes, that constitute the lymphatic system. The
two main types of lymphoma are Hodgkin lymphoma
and non-Hodgkin lymphoma. Lymphoma is the most
common blood cancer and the third most common can-
cer of childhood. Lymphoma occurs when lymphocytes
grow abnormally. The body has two types of lympho-
cytes: B lymphocytes, or B-cells, and T lymphocytes, or
T-cells. B-cells play an important role in making antibod-
ies to fight bacterial infections and T-cells play a role in
fighting viruses and organ rejection in transplant patients.
Although both cell types can develop into lymphomas,
B-cell lymphomas are more common, comprising nearly
85 percent of all non-Hodgkin lymphomas. Like normal
lymphocytes, those that become malignant can grow in
any part of the body, including the lymph nodes, spleen,
bone marrow, blood or other organs.
What Is Non-Hodgkin Lymphoma?
Of the more than 30 types of lymphoma, over 25 are classified
as non-Hodgkin lymphoma (NHL). Nearly all non-Hodgkin
lymphoma cases occur in adults, with the average age of
diagnosis in the 60s. While scientists do not know the exact
causes of non-Hodgkin lymphoma, they do know that it is
not caused by injury or by coming into contact with someone
with the disease. Most people diagnosed with NHL have no
known risk factors, although increasingly many scientists
believe infections may play an important role in causing select
types of non-Hodgkin lymphoma to develop.
What Is T-Cell Lymphoma?
T-cell lymphoma is a rare disease in which T lymphocyte cells
become cancerous. These lymphomas account for between
10 percent and 15 percent of all cases of non-Hodgkin
lymphoma in the United States (approximately 5,000 to
6,000 cases) a year, although some forms of T-cell lymphoma
are more common in Asia, Africa and the Caribbean. There
are many different types of T-cell lymphoma, most of which
are extremely rare, occurring in onl