Acute Myelogenous Leukemia

Acute myelogenous leukemia is a cancer of the blood and bone marrow. Bone marrow is the soft, spongy tissue inside bones where blood cells are produced. In this condition, the bone marrow makes abnormal cells that do not mature properly and interfere with the production of healthy blood cells.

The term acute means the disease tends to progress quickly. Myelogenous refers to the myeloid cells involved. These cells normally develop into red blood cells, white blood cells, and platelets. In acute myelogenous leukemia, these cells become abnormal and multiply uncontrollably.

Acute myelogenous leukemia is the most common type of acute leukemia in adults. It can occur at any age, but it is uncommon before age 45 and most often affects people over age 65. Acute myelogenous leukemia is also known as acute myeloid leukemia, acute myeloblastic leukemia, acute granulocytic leukemia, and acute nonlymphocytic leukemia. Unlike many other cancers, this condition does not have numbered stages.

Symptoms

Symptoms of acute myelogenous leukemia often develop quickly and may resemble those of more common illnesses, such as infections. Common symptoms include:

• Fever

• Bone, back, or stomach pain

• Extreme tiredness or weakness

• Pale or unusually colored skin

• Frequent or recurring infections

• Easy bruising

• Bleeding without a clear cause, such as from the nose or gums

• Shortness of breath

Because these symptoms are not specific, medical evaluation is needed to determine the cause.

Causes

In many cases, the exact cause of acute myelogenous leukemia is not known. Healthcare professionals understand that the disease begins when changes occur in the DNA of certain bone marrow cells.

These changes usually affect myeloid cells, which are immature cells in the bone marrow that normally develop into:

• Red blood cells that carry oxygen

• Platelets that help with blood clotting

• White blood cells that fight infection

DNA contains instructions that control how cells grow, divide, and die. In healthy cells, this process is carefully regulated. In acute myelogenous leukemia, DNA changes give abnormal instructions, causing myeloid cells to grow rapidly and avoid normal cell death.

As a result, large numbers of immature white blood cells, called myeloblasts, are produced. These cells do not function properly and crowd out healthy blood cells in the bone marrow. This leads to low levels of oxygen in the blood, bleeding problems, and increased susceptibility to infections.

Risk factors

Several factors may increase the risk of developing acute myelogenous leukemia:

• Older age, with most cases occurring in people age 65 and older

• Previous cancer treatment with certain chemotherapy drugs or radiation therapy

• Exposure to very high levels of radiation

• Exposure to hazardous chemicals, such as benzene

• Cigarette smoking, which exposes the body to cancer-causing chemicals

• A history of other blood disorders, including myelodysplasia, myelofibrosis, polycythemia vera, or thrombocythemia

• Genetic conditions, such as Down syndrome

• A family history of blood or bone marrow disorders

Many people diagnosed with acute myelogenous leukemia have no known risk factors, and having risk factors does not mean the disease will develop.

Complications

Acute myelogenous leukemia can cause serious complications due to a lack of healthy blood cells. Low red blood cell counts may lead to anemia and fatigue. Low platelet levels increase the risk of bruising and bleeding. A shortage of healthy white blood cells raises the risk of severe infections.

The disease may also spread beyond the bone marrow to organs such as the liver, spleen, lymph nodes, brain, and spinal cord. Treatment-related complications, including infections and organ damage, can also occur.

Without prompt treatment, acute myelogenous leukemia can be life-threatening.

Prevention

There is no known way to prevent acute myelogenous leukemia. Many risk factors, such as age, genetic conditions, or necessary cancer treatments, cannot be changed.

Reducing exposure to known hazards, such as tobacco smoke and harmful chemicals, may lower overall cancer risk. Seeking medical attention for persistent or unusual symptoms can help ensure early diagnosis and timely treatment, which are important for improving outcomes.