About 11,930 new cases of acute myelogenous leukemia are diagnosed each year in the United States. Acute myelogenous leukemia (AML) may be called by several names, including: acute myelocytic leukemia, acute myeloblastic leukemia, acute granulocytic leukemia or acute nonlymphocytic leukemia. AML results from acquired (not inherited) genetic damage to the DNA of developing cells in the bone marrow. The effects are: 1) the uncontrolled, exaggerated growth and accumulation of cells called "leukemic blasts" which fail to function as normal blood cells and 2) the blockade of the production of normal marrow cells, leading to a deficiency of red cells (anemia), and platelets (thrombocytopenia) and normal white cells (especially neutrophils, i.e., neutropenia) in the blood. Causes and Risk Factors About 15 to 20 percent of childhood leukemias are cases of AML. Older people are more likely to develop the disease. The risk increases ten-fold in people from age 30-34 (about 1 case per 100,000 people) to age 65-69 (about 1 case per 10,000 people.) Subtypes of Acute Myelogenous Leukemia Most patients diagnosed with AML have one of eight different patterns of blood cell involvement. These patterns are designated as subtypes and are shown in the table below. Physicians are aided in identifying subtypes based on seeing different types and patterns of cells in a patient's blood or marrow. These patterns are designated as the subtypes listed above. It is possible, although uncommon, for additional subtypes to occur. Additional features may be important in guiding the choice of therapy, including: abnormalities of chromosomes, the cell immunophenotype, the age and the general health of the patient. There are certain chromosomal changes that can give important information for patient management. For example, three chromosomal changes have a relatively favorable prognosis, especially in younger patients. These chromosomal changes account for between 20 to 25 percent of all cases of AML. AML characterized by a transloacation between chromosomes 15 and 17 requires a different treatment that other types of AML. For more information see Acute Promyelocytic Leukemia treatment, page 14 in the free Society's informational booklet Acute Myelogenous Leukamia. Symptoms and Signs To diagnose the disease the blood and marrow cells must be examined. In addition to low red cell and platelet counts, examination of the stained (dyed) blood cells with a light microscope will usually show the presence of leukemic blast cells. This is confirmed by examination of the marrow, which invariably shows leukemic blast cells. The blood and/or marrow cells are also used for studies of the number and shape of chromosomes (cytogenetic examination), immunophenotyping and other special studies, if required. Blood and bone marrow aspirate are used for specific laboratory tests to diagnose and classify the disease. The following tests are used in the diagnosis of the disease. Examination of leukemic cells by cytogenetic techniques permits identification of chromosomes or gene abnormalities in the cells. The immunophenotype and chromosome abnormalities in the leukemic cells are very important guides in determining the approach to treatment and the intensity of the drug combinations to be used. Immunophenotyping The method uses the reaction of antibodies with cell antigens to determine a specific type of cell in a sample of blood cells, marrow cells, or lymph node cells. The antibodies react with specific antigens on the cell. A tag is attached to an antibody so that it can be detected. The tag can be identified by the laboratory equipment used for the test. As cells carrying their array of antigens are tagged with specific antibodies they can be identified; for example, myelogenous leukemic cells can be distinguished from lymphocytic leukemic cells. Normal lymphocytes may be distinguished from leukemic lymphocytes. This method also helps to subclassify cell types, which may, in turn, help to decide on the best treatment to apply in that type of leukemia or lymphoma. The antigen on a cell is referred to as cluster of differentiation or "CD" with an associated number. For example, CD7 and 19 may be present on leukemic lymphoblasts and CD13 and 33 on leukemic myeloblasts. Cytogenetic examination Get More Information Further details of treatment and supportive care and the beneficial and adverse effects of treatment may be obtained from the Society's informational booklet on acute myelogenous leukemia. Read or order online the Society's free publication Acute Myelogenous Leukemia. Contact or call the Information Resource Center at (800) 955-4572.
In most cases the cause of AML is not known. Several factors have been associated with an increased risk of the disease. These include exposure to
AML is not contagious. Uncommon genetic disorders such as Fanconi anemia, Schwachman-Diamond syndrome, Down syndrome and others are associated with an increased risk of AML. Very rarely, an unexpectedly high number of cases of AML may be diagnosed within the same family. It is thought that offspring in these families inherit a gene that makes them more susceptible to developing AML.
Leukemia is a malignant disease (cancer) affecting the bone marrow and blood. AML can develop in a variety of ways; different types of cells may be seen by the physician in blood or marrow. Designation Cell Subtype M0 Myeloblastic, on special analysis M1 Myeloblastic, without maturation M2 Myeloblastic, with maturation M3 Promyeloctic M4 Myelomonocytic M5 Monocytic M6 Erythroleukemia M7 Megakaryocytic
Most patients feel a loss of well-being. They tire more easily and may feel short of breath in the course of normal physical activities. They may have a pale complexion from anemia. Several signs of bleeding caused by a very low platelet count may be noticed. They include black and blue marks or bruises occurring for no reason or because of a minor injury, the appearance of pin-head sized spots under the skin, called petechiae, or prolonged bleeding from minor cuts. Mild fever, swollen gums, frequent minor infections such as pustules or perianal sores, slow healing of cuts or discomfort in bones or joints may occur.
This is a laboratory test that enable the physician to determine the type of disease that is present in the patient. It uses the antigens (proteins) on the cell surface and the antibodies produced by the body that match the antigen.
Cytogenetic examination of tissue is the process of analyzing the number and shape of the chromosomes of cells. The individual, who prepares, examines and interprets the number and shape of chromosomes in cells is called a cytogeneticist. In addition to identifying chromosome alterations, the specific genes affected can be identified in some cases. These findings are very helpful in diagnosing specific types of leukemia, in determining treatment approaches and in following the response to treatment.
The Leukemia & Lymphoma Society offers ongoing education programs featuring leading leukemia specialists discussing the latest issues in the diagnosis and treatment of leukemia. Visit the Leukemia Education Series page to find out about upcoming and archived programs. These programs are offered at no charge.
The Leukemia & Lymphoma Society
1311 Mamaroneck Ave.
White Plains, NY 10605
This site offers comprehensive information about cancers and the diagnosis procedures.
This site offers information about diagnosis and treatment (including immunotherapy), with pages written by several physicians. Go to "cancer links/leukemia/current".
Acute Myelogenous Leukemia - What You Should Know
"Myleoblast" is the term for an undeveloped type of white cell. If myeloblasts are the dominant leukemia cell in the marrow at the time of diagnosis, the leukemia is referred to as "myeloblastic" type. If there are many myeloblasts, but there are some cells developing towards fully formed blood cells, the added designation, "with maturation" is used. If there are cells that are developing features of monocytes ("monocytic" type) or red cells ("erythroleukemia" type), these designations are used, and so forth.
The subclassification of the disease is important. The type of therapy may differ, based on subtype and the course of the disease may be different as well.
Medical history and physical examination
Complete blood counts
Bone marrow examination
Cytogenetic studies
Immunophenotyping
National Cancer Institute
Medicine Online
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