Hematopathology Diseases

Leukemia

Leukemia develops when blood cell production is unregulated and results in increased numbers of abnormal white blood cells in the peripheral blood. The bone marrow, the spongy center of the bones responsible for forming blood cells, may or may not be involved.

There are two major forms of leukemia: acute and chronic. Acute forms of leukemia have increased numbers of immature myeloid cells (acute lymphoblastic leukemia) or lymphocytes (acute myeloid leukemia). "Myeloid" cells are described as blood cells that are not lymphocytes. Chronic forms of leukemia consist of increased numbers of mature myeloid cells (for example, chronic myelogenous leukemia) or lymphocytes (for example, chronic lymphocytic leukemia).

In acute and chronic forms of leukemia, abnormal white blood cells are over-produced and gather in the bone marrow and blood, where they crowd out normal blood cells and interfere with their production and function. These changes lead to some of the common symptoms of leukemia, including pancytopenia (a decrease in all blood cell lineages) and bone pain.

For more information on leukemia, please visit leukemia-lymphoma.org.

Lymphoma

Lymphoma is a type of blood cancer in which lymphocytes divide more rapidly and live longer than normal cells. Lymphoma can develop in a variety of locations including the lymph nodes, spleen and bone marrow. Several lymphomas can have a leukemic phase of disease.

B cell lymphomas are more common than T cell lymphomas, representing over 90% of lymphoid neoplasms worldwide. Broadly, B cell lymphomas can be divided into Hodgkin and non-Hodgkin B cell lymphoma. Hodgkin lymphoma is further classified into classical (nodular sclerosing, lymphocyte-rich, lymphocyte-depleted, mixed cellularity) and non-classical (nodular lymphocyte predominant) types. All forms of Hodgkin lymphoma are characterized by the presence of large abnormal B lymphocytes known as Reed Sternberg cells. There are many types of non-Hodgkin lymphoma, which includes common entities such as follicular lymphoma, mantle cell lymphoma, and diffuse large B cell lymphoma.

For more information on leukemia, please visit leukemia-lymphoma.org.

Multiple Myeloma

Multiple myeloma is a cancer of the plasma cells, a type of white blood cell responsible for producing antibodies. In myeloma, abnormal plasma cells crowd the bone marrow and interrupt normal blood cell production. Multiple myeloma can affect various areas in the body and can be symptomatic or asymptomatic, meaning a patient may or may not show symptoms of the disease.

For more information on multiple myeloma, please visit leukemia-lymphoma.org/myeloma.

Myelodysplastic Syndromes

Myelodysplastic Syndromes, or MDS, are caused by a defect in the maturation and production of healthy blood cells. As a result, symptoms include persistant anemia (low red blood cells), leukopenia (low white blood cell count), and/or thrombocytopenia (low platelets).

For more information on myelodysplastic syndromes please visit www.lls.org/#/diseaseinformation/myelodysplasticsyndromes/.

Myeloproliferative Disorders

Myeloproliferative Disorders (MPD)originate from an abnormal stem cell in the bone marrow. This abnormality causes an overproduction of platelets, white blood cells, and red blood cells, which accumulate in the bone marrow and blood stream.

For more information on myeloproliferative disorders please visit www.lls.org/#/diseaseinformation/myeloproliferativediseases/.