What is Leukemia?
Leukemia is cancer of blood-forming tissues, including bone marrow and the lymphatic system.
Childhood Leukemia Facts
Childhood leukemia represents 24.9% of all new childhood cancer cases.
In the United States, about 3,500 children are diagnosed with leukemia each year.
Leukemia begins in a cell in the bone marrow. The cell undergoes a change and becomes a type of leukemia cell. Once the marrow cell undergoes a leukemic change, the leukemia cells may grow and survive better than normal cells. Over time, the leukemia cells crowd out or suppress the development of normal cells. The rate at which leukemia progresses and how the cells replace the normal blood and marrow cells are different with each type of leukemia. After diagnosis and treatment, many people with leukemia live many good, quality years.
Types of Leukemia
Acute Lymphocytic Leukemia (ALL)
Acute lymphocytic leukemia (ALL) progresses rapidly, replacing healthy cells that produce functional lymphocytes with leukemia cells that can’t mature properly. The leukemia cells are carried in the bloodstream to other organs and tissues, including the brain, liver, lymph nodes and testes, where they continue to grow and divide. The growing, dividing and spreading of these leukemia cells may result in a number of possible symptoms.
Acute Myeloid Leukemia (AML)
Acute myeloid leukemia (AML), also known as acute myelogenous leukemia, acute myeloblastic leukemia, acute granulocytic leukemia or acute nonlymphocytic leukemia, is a fast-growing form of cancer of the blood and bone marrow.
Chronic Lymphocytic Leukemia (CLL)
Chronic lymphocytic leukemia (CLL) is a typically slow-growing cancer that begins in lymphocytes in the bone marrow and extends into the blood. It may also spread to lymph nodes and organs such as the liver and spleen. CLL develops when too many abnormal lymphocytes grow, crowding out normal blood cells and making it difficult for the body to fight infection.
Chronic Myeloid Leukemia (CML)
Chronic myeloid leukemia (CML), also known as chronic myelogenous leukemia, begins in the blood-forming cells of the bone marrow and then, over time, spreads to the blood. Eventually, the disease spreads to other areas of the body.
Hairy Cell Leukemia (HCL)
Hairy cell leukemia (HCL) is a rare subtype of chronic lymphocytic leukemia (CLL) that progresses slowly. HCL is caused when bone marrow makes too many B cells (lymphocytes), a type of white blood cell that fights infection. As the number of leukemia cells increases, fewer healthy white blood cells, red blood cells and platelets are produced.
Myelodysplastic Syndromes (MDS)
Myelodysplastic syndromes (MDS) are a group of closely related diseases in which the bone marrow produces too few functioning red blood cells (which carry oxygen), white blood cells (which fight infection), or platelets (which prevent or stop bleeding), or any combination of the three. The different types of myelodysplastic syndromes are diagnosed based on certain changes in the blood cells and bone marrow. The cells in the blood and bone marrow (also called myelo) usually look abnormal (or dysplastic), hence the name myelodysplastic syndromes.