The information on this page was reviewed and approved by
Maurie Markman, MD, President, Medicine & Science at CTCA.
This page was updated on April 2, 2021.
Leukemia is cancer that forms in blood-forming tissue. The disease is characterized by the uncontrolled growth of blood cells, usually white blood cells in the bone marrow. White blood cells are a fundamental component of the body's immune response. Leukemia cells crowd out and replace normal blood and marrow cells.
Although many types of leukemia exist, some affect adults more commonly than others.
The exact cause of leukemia isn't known, but researchers believe the disease develops due to mutations in the DNA of certain blood cells, caused by either genetic or environmental factors.
Some risk factors for leukemias that most commonly affect adults include:
Learn more about risk factors for leukemia
In the United States, an estimated 61,090 Americans will be diagnosed with leukemia in 2021, according to the American Cancer Society. Leukemia is diagnosed more often in men than in women. Although people of any age can develop the disease, it is most common in adults over 65 years old.
Leukemia is categorized by the type of white blood cells affected and by how quickly the disease grows.
Types of leukemia include:
Learn more about leukemia types
The symptoms of leukemia generally depend on the type of leukemia, how quickly it grows and at what stage the disease is diagnosed. Many signs of leukemia resemble flu-like symptoms.
Common leukemia symptoms include:
Learn more about leukemia symptoms
Diagnosing leukemia generally involves examining cells from the blood and bone marrow. Diagnostic tests for leukemia often include:
Learn more about diagnosing leukemia
Treatment for leukemia generally depends on the type of the disease, and each patient's unique diagnosis and needs.
Treatment options may include:
Learn more about treatments for leukemia
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