Leukemia
Leukemia is a type of cancer that forms in blood cells. Each year, nearly 50,000 people in the U.S. are diagnosed with the disease.
About Leukemia
Leukemia develops when bone marrow, the soft material inside the bones that produces blood cells, forms abnormal white blood cells called leukemia cells.
Leukemia cells enter the bloodstream and crowd out normal white blood cells, red blood cells, and platelets. The cancerous cells can travel throughout the body and invade organs and tissue.
Leukemia may be chronic or acute. Chronic leukemia develops slowly and worsens over time. Acute leukemia develops rapidly and spreads quickly.
Leukemia may begin in lymphocytes, a type of white blood cell that develops into infection-fighting tissue called lymphoid or lymphatic tissue. The disease may also begin in the myeloid cells, which develop into red blood cells, white blood cells or platelets. The four major types of leukemia are:
- Chronic lymphocytic leukemia (CLL)
- Chronic myeloid leukemia (CML)
- Acute lymphocytic leukemia (ALL)
- Acute myeloid leukemia (AML)
Acute myeloid leukemia is the most common leukemia in adults. Acute lymphocytic leukemia is the most common leukemia in children.
Who’s at Risk?
Leukemia is most often diagnosed in people in their 60s, but it can occur in people of all ages. It is the most common cancer in children, but 10 times more adults than children are affected by the disease.
Risk Factors
The following risk factors have been found to increase the risk of leukemia:
- Radiation: Exposure to high levels of radiation caused by atomic bomb explosions, nuclear power plant accidents and some medical treatments.
- Certain chemicals: Exposure to chemicals like benzene or formaldehyde.
- Chemotherapy: Treatment with certain anti-cancer drugs.
- Inherited diseases: Down syndrome and other genetic diseases caused by abnormal chromosomes.
- HTLV-I: Human T-cell leukemia virus-1 can cause a rare type of chronic lymphocytic leukemia.
- Blood disorders: Certain diseases like myelodysplastic syndrome.
- Smoking cigarettes
Treatment
Treatment options depend on the type and extent of the leukemia. The most common treatment is chemotherapy, which uses anti-cancer drugs to kill the cancerous cells. Immunotherapy, radiation therapy, stem cell transplantation, and bone marrow transplantation may also be part of the treatment plan.
Some information on this page is provided by the National Cancer Institute and the American Cancer Society.