Other names: acute myelogenous leukemia, AML
Acute myeloid leukemia (AML) is a cancer that affects the blood and bone marrow. The signs and symptoms of AML vary but may include easy bruising; bone pain or tenderness; fatigue; fever; frequent nosebleeds; bleeding from the gums; shortness of breath; and/or weight loss. AML is one of the most common types of leukemia among adults and is rarely diagnosed in people under age 40. There are many potential causes of AML such as certain blood disorders, inherited syndromes, environmental exposures, and drug exposures; however, most people who develop AML have no identifiable risk factor. Treatment may include a combination of chemotherapy, radiation therapy, bone marrow transplant and/or other drug therapy.
Pathophysiology and Epidemiology
There are many potential causes of AML such as certain blood disorders, inherited syndromes, chemical exposures, ionizing radiation, environmental exposures, and drug exposures; however, most people who develop AML have no identifiable risk factor.
Signs and Symptoms
General signs and symptoms of the early stages of AML may mimic those of the flu or other common diseases. Signs and symptoms may vary based on the type of blood cell affected. Signs and symptoms of AML include:
- Bone pain
- Lethargy and fatigue
- Shortness of breath
- Pale skin
- Frequent infections
- Easy bruising
- Unusual bleeding, such as frequent nosebleeds and bleeding from the gums
The first clue to a diagnosis of AML is typically an abnormal result on a complete blood count. While leukocytosis is a common finding, and leukemic blasts are sometimes seen, AML can also present with isolated decreases in platelets, red blood cells, or even with leukopenia. While a presumptive diagnosis of AML can be made via examination of the peripheral blood smear when there are circulating leukemic blasts, a definitive diagnosis usually requires an adequate bone marrow aspiration and biopsy.
Marrow or blood is examined via light microscopy, as well as flow cytometry, to diagnose the presence of leukemia, to differentiate AML from other types of leukemia (e.g. acute lymphoblastic leukemia), and to classify the subtype of disease. A sample of marrow or blood is typically also tested for chromosomal abnormalities by routine cytogenetics or fluorescent in situ hybridization. Genetic studies may also be performed to look for specific mutations in genes such as FLT3, nucleophosmin, and KIT, which may influence the outcome of the disease.
Cytochemical stains on blood and bone marrow smears are helpful in the distinction of AML from ALL, and in subclassification of AML. The combination of a myeloperoxidase or Sudan black stain and a nonspecific esterase stain will provide the desired information in most cases. The myeloperoxidase or Sudan black reactions are most useful in establishing the identity of AML and distinguishing it from ALL. The nonspecific esterase stain is used to identify a monocytic component in AMLs and to distinguish a poorly differentiated monoblastic leukemia from ALL.
The diagnosis and classification of AML can be challenging, and should be performed by a qualified hematopathologist or hematologist. In straightforward cases, the presence of certain morphologic features (such as Auer rods) or specific flow cytometry results can distinguish AML from other leukemias; however, in the absence of such features, diagnosis may be more difficult.
According to the widely used WHO criteria, the diagnosis of AML is established by demonstrating involvement of more than 20% of the blood and/or bone marrow by leukemic myeloblasts. AML must be carefully differentiated from “preleukemic” conditions such as myelodysplastic or myeloproliferative syndromes, which are treated differently.
Amy Burd, PhD: Beat AML Trial: Rapid Genetic Screening in Acute Myeloid Leukemi
Management and Treatment
Traditional treatment for AML usually involves high-dose chemotherapy. For elderly patients who cannot receive intensive treatment, venetoclax in combination with azacitidine, decitabine, or low-dose cytarabine (LDAC) has been approved.
Andrew Krivoshik, MD, PhD: Important Considerations When Treating AML
FDA approved treatments for AML include:
- Glasdegib (Brand name: Daurismo)
- Enasidenib (Brand name: Idhifa)
- Gemtuzumab ozogamicin (Brand name: Mylotarg)
- Midostaurin (Brand name: Rydapt)
- Ivosidenib (Brand name: Tibsovo)
- Venetoclax (Brand name: Venclexta)
- Cytarabine and daunorubicin liposome injection (Brand name: Vyxeos)
- Gilteritinib (Brand name: Xospata)
Unfortunately, AML patients often experience a relapse or become refractory to treatment.
Andrew Krivoshik, MD, PhD: New Education Resource Available for Relapsed or Refractory AML Patients
For a full list of clinical trials relating to AML, go here.
To learn more about rare cancers, visit our Rare Cancers page