Acute Myeloid Leukemia Facts

April 19, 2024 
This page was reviewed under our medical and editorial policy by Guido Marcucci, M.D., Chair, Department of Hematologic Malignancies Translational Science, City of Hope Duarte

A cancer of the blood and bone marrow, acute myeloid leukemia (AML) is the most common type of leukemia diagnosed in adults, accounting for 80% of all adult leukemias.

It is, however, relatively rare. AML accounts for about 1% of all cancers. The American Cancer Society projects about 20,800 new cases of AML in the United States in 2024 and about 11,220 deaths.

What Is AML?

Leukemia refers to a group of cancers of the blood cells. The specific type of leukemia is based on the type of blood cell affected and how quickly the cancer progresses.

In acute myeloid leukemia, the bone marrow produces a large number of white blood cells (called myeloblasts or blasts) that fail to mature into healthy white blood cells.

As these abnormal cells increase, they build up in the bone marrow and quickly move into the blood where they crowd out healthy platelets, red blood cells and other white blood cells. A low red blood cell count may make a person feel tired and out of breath. A shortage of platelets may lead to bleeding problems, including nosebleeds and bruising.

The abnormal cells may also spread to other parts of the body, including the spleen, lymph nodes, liver and, sometimes, the brain.

Causes of Acute Myeloid Leukemia

The cause of AML is not fully understood, but DNA changes play an important role. DNA contains the instructions for cells to develop, survive and reproduce. Changes in DNA of bone marrow cells may cause them to become leukemia cells. 

DNA mutations may be inherited from parents or result from exposure to radiation or cancer-causing chemicals. Most genetic changes involved in the development of AML occur over a person’s lifetime, not before birth, and usually the cause is not clear. These DNA changes may stop bone marrow cells from maturing normally or prompt cells to grow out of control.

Changes in the FLT3, c-kit and RAS genes are often seen in AML. There are many types of AML, and different gene and chromosome changes are seen in different types of AML. Researchers are investigating the underlying causes of these changes and their role in causing leukemia.

Acute Myeloid Leukemia Risk Factors

Certain risk factors are linked with a higher risk for developing AML. These include those listed below.

Advancing age: The average age for an AML diagnosis is 68, and this cancer is rarely diagnosed before age 45.

Male gender: AML is slightly more common among men than women.

Smoking and chemicals: Exposure to certain chemicals, such as benzene, which is used in many industries, as well as cigarette smoke, gasoline and motor vehicle exhaust, may increase AML risk.

History of chemotherapy for a previous cancer: Chemotherapy drugs known as topoisomerase II inhibitors are linked to AML.

History of certain blood disorders: Some blood disorders appear to increase AML risk. These include chronic myeloproliferative disorders, such as polycythemia vera, essential thrombocythemia and idiopathic myelofibrosis. AML risk also rises if these disorders are treated with radiation therapy.

History of myelodysplastic syndromes and other bone marrow disorders: Myelodysplastic syndromes (MDS) occur when the blood-forming cells in the bone marrow become abnormal. About one in three people with MDS will develop AML.

Other bone marrow disorders associated with a greater risk for developing AML include the following.

Aplastic anemia: A condition in which the bone marrow fails to make enough new blood cells.

Certain genetic syndromes or chromosome irregularities: These may include Down syndrome, Klinefelter syndrome, Fanconi anemia, Diamond Blackfan anemia and familial platelet disorder. Mutations to the GATA2, ETV6, CEBPA and RUNX1 genes may also increase AML risk. The chromosomal abnormality trisomy 8 may also be linked with a higher risk for AML.

Family history of AML: Someone with an identical twin who was diagnosed with AML before age 1 has a very high risk for this leukemia.