Leukemia is cancer of the body's blood-forming tissues, including the bone marrow and lymph system. When this condition occurs, bone marrow produces a large number of abnormal white blood cells — or, in some cases, a large number of red blood cells or platelets.

Normal white blood cells are potent infection fighters. But in people with leukemia, abnormal white blood cells tend to accumulate, blocking production of normal white blood cells and impairing the ability to fight infection.

Treatment for leukemia is complex. Most patients are treated with chemotherapy. Some also may have radiation therapy, a blood or marrow transplant (BMT) or biological therapy.

Many people believe leukemia only affects children, but roughly 10 times as many adults as children are diagnosed with this cancer. New cases of leukemia number nearly 30,000 annually in the United States.

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Types of Leukemia

There are six main types of leukemia:

  • Acute Myeloid Leukemia (AML) — Occuring in both adults and children, this type of leukemia is sometimes called acute nonlymphocytic leukemia (ANLL).
  • Acute Lymphoblastic Leukemia (ALL) — This is the most common type of leukemia in young children, but also affects adults, including those who are age 65 and older.
  • Chronic Myeloid Leukemia (CML) — Although this condition occurs mainly in adults, a very small number of children also develop CML.
  • Chronic Lymphocytic Leukemia (CLL) — This condition most often affects adults over the age of 55. While it sometimes occurs in younger adults, it almost never affects children.
  • Multiple Myeloma (MM) — This condition mainly affects older adults and is associated with painful bone lesions and the production of excess antibody protein. Kidney damage may occur.
  • Myelodysplastic Syndrome (MD) — This condition is sometimes called "pre-leukemia" because of its propensity to turn in to AML. It is characterized by low blood counts, the need for transfusions, and infections.

All types of leukemia are treatable and some are potentially curable.

Classifications of Leukemia

Leukemia is grouped by how quickly it develops, as well as the type of blood cells it affects. The different forms of leukemia vary greatly in their nature and seriousness and they are classified as either "acute" or "chronic."

  • Acute leukemias are more aggressive with severe symptoms and cause major medical problems quickly. Without effective treatment, most patients will die in days to weeks.
  • Chronic leukemias develop at a much slower rate. Some do not require treatment for months or years.

Leukemias also are classified as "myeloid" or "lymphoid." This refers to the type of white blood cell that has become cancerous. Myeloid cells give rise to neutrophils, an important type of white blood cell that kills bacteria, as well as red blood cells (which deliver oxygen to the tissues) and platelets (which help clot the blood). Lymphoid cells give rise to lymphocytes, which protect against bacterial germs, including viruses.

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Related Information

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San Francisco, CA 94143
Existing Patients: (415) 353-2421
New Patients: (415) 353-2051
Fax: (415) 353-2467
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