Leukemia
Leukemia is a type of blood cancer that begins in the bone marrow. Bone marrow is the soft tissue in the center of the bones, where blood cells are produced.
The term leukemia means white blood. White blood cells (leukocytes) are used by the body to fight infections and other foreign substances. Leukocytes are made in the bone marrow.
Leukemia leads to an uncontrolled increase in the number of white blood cells.
The cancerous cells prevent healthy red cells, platelets, and mature white cells (leukocytes) from being made. Life-threatening symptoms can then develop as normal blood cells decline.
The cancer cells can spread to the bloodstream and lymph nodes. They can also travel to the brain and spinal cord (the central nervous system) and other parts of the body.
Leukemia can affect children and adults.
Leukemias are divided into two major types:
- Acute (which progresses quickly)
- Chronic (which progresses more slowly)
The main types of leukemia are:
- Acute lymphocytic leukemia (ALL)
- Acute myelogenous leukemia (AML)
- Chronic lymphocytic leukemia (CLL)
- Chronic myelogenous leukemia (CML)
A small amount of bone marrow is removed during a bone marrow aspiration. The procedure is uncomfortable, but can be tolerated by both children and adults. The marrow can be studied to determine the cause of anemia, the presence of leukemia or other malignancy, or the presence of some storage diseases, in which abnormal metabolic products are stored in certain bone marrow cells.
This picture shows the darkly-stained lymph cells (lymphoblasts) seen in acute lymphocytic leukemia (ALL), the most common type of childhood leukemia.
Note multiple Auer rods which are found only in acute myeloid leukemias, either myeloblastic or monoblastic. These rods consist of clumps of azurophilic granule material.
This is a microscopic view of bone marrow from a person with chronic lymphocytic leukemia. It shows predominantly small, mature lymphocytes.
This high-power microscopic view of a blood smear from a person with classical CML shows predominantly normal-appearing cells with intermediate maturity.
Oil immersion field demonstrating myeloid cells of all degrees of maturity.
Low power view showing marked hypercellularity with a broad-spectrum of myeloid and erythroid cell types and marked myeloid hyperplasia.
References
Appelbaum FR. Acute leukemias in adults. In: Niederhuber JE, Armitage JO, Kastan MB, Doroshow JH, Tepper JE, eds. Abeloff's Clinical Oncology. 6th ed. Philadelphia, PA: Elsevier; 2020:chap 95.
Hunger SP, Teachey DT, Grupp S, Aplenc R. Childhood leukemia. In: Niederhuber JE, Armitage JO, Kastan MB, Doroshow JH, Tepper JE, eds. Abeloff's Clinical Oncology. 6th ed. Philadelphia, PA: Elsevier; 2020:chap 93.
Version Info
Last reviewed on: 1/25/2022
Reviewed by: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
