Lymphomas are any cancers of the lymphatic tissues. They are distinguished/classified by the World Health Organization (WHO) system, using the latest information on the appearance and growth pattern of the lymphoma cells and genetic features, including whether or not it is a Hodgkin lymphoma, a T-cell or B-cell lymphoma, and the site from which the lymphoma arises.
Hodgkin lymphoma is marked by the presence of a type of cell called the Reed–Sternberg cell.
Non-Hodgkin lymphomas, which are defined as being all lymphomas except Hodgkin lymphoma, are more common than Hodgkin lymphoma. A wide variety of lymphomas are in this class, and the causes, the types of cells involved, and the prognosis vary by type. The incidence of non-Hodgkin lymphoma increases with age. It is further divided into several subtypes.
Of the over 66 forms of lymphoma, some are categorized as indolent (e.g. follicular lymphoma) and are compatible with a long life, whereas other forms are aggressive (e.g. Burkitt lymphoma or Diffuse Large B-cell lymphoma), causing rapid deterioration and death. However, most of the aggressive lymphomas respond well to treatment and many are curable.
Aggressive non-Hodgkin lymphomas progress rapidly. They make up about 60 percent of all NHL cases in the United States.
Aggressive NHL subtypes include:
- AIDS-associated lymphoma
- Anaplastic large cell lymphoma
- Burkitt lymphoma
- Central nervous system (CNS) lymphoma
- Diffuse large B-cell lymphoma (DLBCL)
- Mantle cell lymphoma
- Transformed lymphoma
- Peripheral T-cell lymphoma (most types)
Indolent non-Hodgkin lymphoma subtypes progress slowly. They make up about 30 percent of all NHL cases in the United States.
Indolent NHL subtypes include:
- Cutaneous T-cell lymphoma (mycosis fungoides and Sézary syndrome)
- Follicular lymphoma
- Lymphoplasmacytic lymphoma and Waldenström macroglobulinemia
- Marginal zone lymphoma
- Small cell lymphocytic lymphoma (SLL) and chronic lymphocytic leukemia (CLL)