Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a type of leukemia that starts in very early or immature forms of white blood cells called myeloblasts (or blasts for short). It’s also known as acute myelogenous leukemia. In some cases, the leukemia cells can be early red blood cells called megakaryocytes. 

As the leukemia cells grow, they crowd out the normal cells in the bone marrow. This can lead to not enough different types of healthy blood cells. People with AML have too many white blood cells in their blood. But these cells are not normal and don't help fight infections. In fact, people with AML often get more infections than people without it. AML can also lead to not enough red blood cells. This condition is called anemia, and it can cause fatigue. AML can lead to not enough platelets, too. This can lead to excess bleeding or bruising. 

AML is a type of acute leukemia. This means it tends to grow fast. It needs to be treated right away.

AML comes in many subtypes. They are based on what type of cells the leukemia starts in and how mature the cells are. Which subtype of AML you have can affect both your treatment and prognosis (outlook). The main classification system of subtypes includes:

• M0. This is undifferentiated AML. 

• M1. This is AML with minimal maturation.

• M2. This is AML with maturation.

• M3. This is acute promyelocytic leukemia (APL).

• M4. This is acute myelomonocytic leukemia (AMML).

• M4eo. This is AMML with eosinophilia.

• M5. This is acute monocytic leukemia.

• M6. This is acute erythroid leukemia.

• M7. This is acute megakaryoblastic leukemia.

AML may be broken down into other subtypes with a different system than this one. Ask your healthcare provider which system he or she is using and what it means for you. The subtype of AML may determine which treatment is most appropriate.

Another aspect of typing that's done for AML is looking for certain genetic changes in the leukemia cells. These changes can help your healthcare provider decide on the best treatment plan.

Symptoms of AML can be different in each person. The most common symptoms include:              

• Bleeding.

• Bruising.

• Fever .

• Recurring or frequent infections.

• Feeling weak.

• Feeling tired (fatigue).

• Pale skin.

• Shortness of breath.

• Chest pain.

• Dizziness.

• Headaches.

• Blurred vision.

• Aches in bones and joints.

• Swollen gums, lymph nodes, liver, or spleen.

• Loss of appetite and weight loss.

• Rashes of tiny flat red spots (caused by bleeding).

• Sores or wounds that don't heal.

Many of these symptoms can be caused by other health problems. In fact, most of them are more likely to be caused by something else. But it is important to see your healthcare provider if you have these symptoms. Only a healthcare provider can tell if you have AML, another type of cancer, or another medical problem that needs to be treated.

If your healthcare provider thinks you might have AML, you will need certain exams and tests to be sure. Your healthcare provider will ask you about your health history, your symptoms, risk factors, and family history of disease. Your healthcare provider will also give you a physical exam.

You may have one or more of the following tests:

Blood tests

Blood is taken from the arm or hand with a needle. The blood is then tested in various ways (see below).

Bone marrow aspiration and biopsy

This procedure is done by taking out small amounts of bone marrow. Bone marrow samples are usually taken from the back of the hip (pelvic) bone. For the bone marrow aspiration, the area over the hip is numbed. A thin, hollow needle is inserted through the skin and into the hip bone. A syringe is used to pull out a small amount of liquid bone marrow. You may have some brief pain when the marrow is removed. A bone marrow biopsy is usually done just after the aspiration. A small piece of bone and marrow is removed with a slightly larger needle that is pushed down into the bone. The biopsy may also cause some brief pain. The bone marrow is then checked for leukemia cells and tested in various ways (see below).

The tests done on blood or bone marrow samples may include:

• Complete blood count (CBC). This test measures the numbers of different types of cells in the blood. People with AML typically have too many early forms of white blood cells, called blasts.

• Immunophenotyping. These tests are done on either blood or bone marrow or both. The tests measure the types and amounts of certain substances called antigens on the surface of leukemia cells. This can be used to see if you have AML, and which subtype you have. Results of this test may take several days.

• Cytogenetics. For this test, cells are grown in a lab for a week or more. The chromosomes inside the cells are then stained with special dyes and viewed with a microscope. Major changes in the chromosomes can often be seen with this test. But smaller changes may not be visible.

• Fluorescence in situ hybridization (FISH). This test is another way to look for changes in chromosomes. The cells in the sample are stained with fluorescent dyes that will only attach to certain parts of chromosomes. The cells are then viewed with a microscope using a special light. This test can find some chromosome changes that can't be seen with standard cytogenetic testing. It is also a quicker test.

• Polymerase chain reaction (PCR). This is a very sensitive test that can detect very low levels of leukemia cells in a test sample. It works by increasing the amount of genetic material in a sample so that it can be detected. This test can find small levels of chromosome changes that other tests can’t find. 

Finding the gene changes in your leukemia cells helps your healthcare provider know the exact type of AML you have.

When your healthcare provider has the results of your tests, he or she will contact you with the results. Your provider will talk with you about other tests you may need if AML is found. Make sure you understand the results and what follow-up you need.