Leukemia Facts

What Is Leukemia?


Leukemia is a disorder involving blood cells. Healthy cells form in the bone marrow and mature into red blood cells (to deliver oxygen and nutrients to the body’s tissues), white blood cells (to fight infections) and platelets (to stop bleeding).

In patients with leukemia, these cells do not mature as they should or they transform into irregular blood cells that do not function normally. As abnormal cells build up in the bone marrow and bloodstream, the patient may experience anemia, susceptibility to infections and bleeding that does not clot due to the lack of functional red blood cells, white blood cells and/or platelets.

On a general scale, leukemia is classified by the types of cells affected (myeloid or lymphoid) and whether it is fast- or slow-growing (acute or chronic). As such, the four major subtypes of leukemia are:

What Risk Factors Are Linked to Leukemia?

Factors that can elevate risk of leukemia include:

  • A personal or family history of leukemia or blood disorders
  • Prior treatment with radiation or chemotherapy
  • Exposure to radiation or certain chemicals, including benzene, formaldehyde and Agent Orange
  • Infections with specific viruses, such as the Epstein-Barr virus or human T cell lymphoma/leukemia virus (HTLV-1)
  • Being male
  • Smoking

What Are the Symptoms of Leukemia?

Common symptoms associated with leukemia include:

  • The unexpected loss of weight or appetite
  • Fatigue
  • Anemia
  • Frequent or long-lasting infections
  • Excessive bleeding and bruises, or bleeding that does not stop
  • Enlarged spleen or lymph nodes
  • Petechiae (flat, round and red pinpoint spots under the skin)
  • Shortness of breath
  • Fevers, chills and other flu-like symptoms
  • Night sweats


Although these symptoms can be caused by other conditions, you should check with a doctor – preferably a hematologist – to get a definitive diagnosis.

Sources: National Cancer Institute and American Cancer Society