are cancers of the lymphoid system and include distinct entities defined by clinical, histologic,
immunologic, molecular, and genetic characteristics. Based on histologic characteristics, lymphomas are divided into
two major subgroups: Hodgkin’s disease and non-Hodgkin’s lymphoma.
The etiology of
is unclear, but indirect evidence indicates a viral cause. Signs and symptoms of
Hodgkin’s disease are distinctive—patients present with a slow, insidious, superficial lymphadenopathy with lymph
(cervical, supraclavicular, mediastinal) nodes that are firm, rubbery, and freely movable. The disease spreads in a
generally predictable manner to contiguous lymph nodes via lymphatic channels.
Because of many histologic subtypes and ongoing biological, pathological, and clinical studies, classifying
lymphomas is controversial. In 1999, the World Health Organization suggested a change in the subtyping of Hodgkin’s
disease that would assist physicians in selecting treatment protocols.
Treatment for Hodgkin’s disease may include radiation, a combination of radiation and chemotherapy, or
chemotherapy alone. The cure rate for newly diagnosed cases is higher than 90%, making Hodgkin’s disease one of the
most treatable forms of cancer. Bone marrow transplant or peripheral progenitor (stem) cell transplants with high-dose
chemotherapy are recommended for patients who have relapsed/failed primary chemotherapy regimen.
is a malignancy of the B lymphocyte and T lymphocyte cell systems. Abnormal
lymphocytes accumulate and form masses in lymph tissue such as the lymph nodes, spleen, or other organs. Malignant
lymphocytes travel through the circulation to distant sites. Common extranodal sites include the lungs, liver,
gastrointestinal tract, meninges, skin, and bones. Most patients with non-Hodgkin’s lymphoma fall into two broad
categories related to their clinical features: the nodular indolent type, and the diffuse, aggressive lymphomas. Malignant
lymphocytes accumulate in lymph nodes. If the normal follicular structure of the nodes remains intact, the lymphoma is
called follicular or nodular. When malignant cells destroy the follicles, the lymphoma is considered diffuse. For
treatment purposes, they may be separated into two categories: low-grade lymphoma and aggressive lymphoma (which
includes intermediate-grade and high-grade lymphomas). Treatment for non-Hodgkin’s lymphomas may includes
watching and waiting, radiation, chemotherapy (usually multiple combinations of antineoplastic agents), monoclonal
antibodies (rituximab [Rituxan]), peripheral progenitor (stem) cell transplant or bone marrow transplant. With or
without treatment, low-grade lymphomas can transform into a more aggressive lymphoma, or the tumor replaces the
hematopoietic and lymphoid tissue, which leads to multiple systemic dysfunction and death. Intermediate- and high-