Adult acute myeloid leukemia (AML) is a cancer of the blood stem cells. AML is caused by genetic damage to blood stem cells in the bone marrow, resulting in uncontrolled growth and accumulation of undeveloped cells called “leukemic blasts,” which cannot function as normal blood cells.
Acute Myeloid Leukemia Causes
Very rarely, AML may occur in unexpectedly high frequencies in certain families. Older people are more likely to develop the disease.
Several factors have been shown to be associated with an increased risk of AML, including:
- Exposure to high doses of radiation and chemotherapy
- Exposure to benzene
- Genetic disorders such as Fanconi anemia and Down syndrome, etc.
Acute Myeloid Leukemia Symptoms
The early symptoms of AML may present in a similar fashion as flu or other common illnesses. Possible signs of adult AML include:
- Fever and acquiring infections more easily than normal
- Exhaustion and/or shortness of breath
- Paleness (from anemia)
- Fatigue and weakness
- Loss of appetite and/or weight loss
- Easy bruising or bleeding more easily than normal
To differentiate from other, more common illnesses, doctors use tests that examine the blood and bone marrow to detect and diagnose adult AML, including:
- Complete panel of red blood cells, white blood cells and platelets
- Blood chemistry studies to monitor the internal organ functions like kidneys and liver and to check electrolytes
- Bone marrow aspiration and biopsy (looking for abnormal cells)
- Flow cytometry to identify cells based on the types of antigens or markers on the surface of the cell
- Genetic studies such as evaluation of chromosomal and molecular changes in the cancer cells
Acute Myeloid Leukemia Treatment
The goal of the initial treatment or induction treatment of AML is to reduce the number of leukemia cells to the point where the healthy blood cells can grow back. Different treatments and appropriate courses of action are tailored to individual patients and based on multiple factors including:
- The specific type of AML
- Whether the AML has spread outside the blood and bone marrow
- Patient age, history of blood disorders and any previous chemotherapy treatment for AML or other cancers
- Risk of recurrence of the AML
AML is treated in two parts: induction chemotherapy and consolidation therapy. This usually consists of a combination of two chemotherapy agents, cytarabine and an anthracycline (daunorubicin or idarubicin). This regimen, known as 7+3, is always given inside the hospital as an inpatient. The goal is then to kill off all leukemic cells to an undetectable level and restore normal blood cell production, a state called complete remission.
Further chemotherapy treatment necessary to kill the remaining or “hiding” leukemia cells is known as consolidation therapy.
AML has different subtypes based on chromosomal abnormalities, the degree of aggressiveness and resistance to the initial treatment. As such, patients with favorable risk disease continue 3-4 more courses of consolidation chemotherapy. Patients with unfavorable risk AML are advised to undergo an allogeneic hematopoietic stem cell (or bone marrow) transplantion.
A previous study conducted in the Fred Hutchinson Cancer Research Center showed that nearly half of patients with unfavorable risk AML who received bone marrow transplant after their first remission survived at least five years, compared to only one-fifth of those treated with chemotherapy only. That dramatic result now means that many AML patients undergo bone marrow or stem cell transplantation while they are in the first remission. With improved treatments for transplant complications, five-year survival rates for people with AML are as high as 70% (Fred Hutchinson Cancer Research Center website).
The physicians at Colorado Blood Cancer Institute (CBCI) are specialists in the care of patients with AML.