Blood Cancer

Blood cancer (also called hematologic cancer or hematologic malignancy) occurs when typical blood cell development is disrupted by uncontrolled growth of abnormal blood cells. This dysfunction in cellular growth affects the ability of normal blood cells to function as they typically would. There are several different types of blood cancer, each of which originates in different components of the blood.

Cancer that originates in white blood cells is known as leukemia. Leukemia affects a particular type of white blood cell called lymphocytes (lymphocytic leukemia) or other blood cells (myelogenous leukemia), and may either grow fast (acute) or slow (chronic). Ultimately, this type of blood cancer prevents white blood cells from fighting infections. 

Blood cancer that originates in the lymphatic system (an important part of the immune system involved in fighting infections) is known as lymphoma, which, like leukemia, also affects lymphocytes. Lymphoma is further subdivided into Hodgkin lymphoma (or Hodgkin’s disease) and non-Hodgkin lymphoma. Hodgkin lymphoma is unique in that only a minority of the cells in the tumor are malignant (cancerous).

Blood cancer that originates in plasma cells in the bone marrow is known as myeloma. Plasma cells are white blood cells that produce antibodies that protect against infections. In myeloma, the myeloma cells crowd out the normal plasma cells, preventing the normal production of infection-fighting antibodies. Because myeloma typically occurs at many sites in the bone marrow, it is often referred to as multiple myeloma.