Learning About Lymphoma
What are the different types of low-grade (Indolent) Non-Hodgkin's Lymphoma?
(also called small cleaved cell or mixed cell lymphoma)
Follicular B-cell lymphomas are relatively common, making up 5% to 20% of all NHLs. These lymphomas typically affect adults, particularly middle-aged and older adults. Because they are common, they are used as a model for the treatment of all indolent lymphomas. Between 40% and 60% of all indolent follicular lymphomas may eventually transform into a more aggressive lymphoma. Indolent forms that transform into more aggressive lymphomas are more difficult to treat than those that are aggressive at diagnosis. Because the cells circulate in the blood, people with follicular B-cell NHL often have lymphoma in many parts of the body (often the bone marrow). Follicular lymphomas are divided into three types according to the numbers of small and large cells: small-cleaved cell type, mixed small-cleaved and large cell type, or large cell type.
Small lymphocytic lymphoma
Small lymphocytic lymphoma (SLL) is often found in both the lymph nodes and the bone marrow. Accounting for about 4% of NHLs, SLL is initially sensitive to treatment, but it may eventually become resistant or transform into a more aggressive, large cell lymphoma. Although lymphomas that are aggressive at diagnosis are curable, indolent lymphomas that transform into more aggressive types are more difficult to cure. About 30% of all cases of SLL progress to a higher grade such as diffuse large cell lymphoma (called Richter's syndrome). Over time, 1O% to 20% of all cases of SLL progress to chronic lymphocytic leukemia.
Chronic lymphocytic leukemia
Chronic lymphocytic leukemia (CLL) is almost identical to SLL. In CLL, the cancer cells are found in the blood, while in SLL the cancer cells are in the lymphatic system. CLL accounts for about 30% of adult leukemias in the United States. (Note: Leukemia is the term used when cancerous cells are found in the blood.)
Marginal zone lymphoma
(also called Monocytoid B-cell or Mucosa-associated lymphatic tissue lymphomas)
Marginal zone tumors are indolent B-cell lymphomas that may occur either in the lymph nodes (nodal) or outside the lymph nodes (extranodal). Nodal marginal zone B-cell lymphomas are uncommon and are often known as monocytoid B-cell lymphomas. The median age at diagnosis is 65.
Mucosa-associated lymphatic tissue lymphomas (also called MALT or MALToma ) are forms of marginal zone lymphomas that affect places outside the lymph nodes (such as the gastrointestinal tract, thyroid, breast, or skin). These are indolent B-cell lymphomas. Many of those who develop it have a history of an autoimmune disease. A higher incidence of this disease is seen in patients who have been infected with h. Pylori of the stomach.
(also called immunocytoma or lymphoplasmacytic)
This B-cell lymphoma is rare, occurring in only 1% to 2% of people with NHL. This disease usually affects older adults and there is often bone marrow involvement at the time of diagnosis.
Cutaneous T-Cell Lymphoma (CTCL)
Cutaneous T-cell lymphomas (CTCL) are indolent (low-grade) cancers that usually start in or on the skin*. When caught early, this form of NHL is called mycosis fungoides. The advanced form of the same disease may be clinically indistinguishable from aggressive, high-grade, B-cell lymphoma, and may involve other organ systems. CTCL comprises about 2-3% of all NHLs. The age at presentation is usually between 55-60 years.