Cancer starts when cells in a part of the body begins to grow out of control and can spread to other areas of the body. There are many kinds of cancer. Cells in nearly any part of the body can become cancer. To learn more about how cancers start and spread, see What Is Cancer?

Leukemias are cancers that start in cells that would normally develop into different types of blood cells. Here we will talk about acute myeloid leukemia (AML).

Acute myeloid leukemia (AML) has many other names, including acute myelocytic leukemia, acute myelogenous leukemia, acute granulocytic leukemia, and acute non-lymphocytic leukemia.

“Acute” means that this leukemia can progress quickly if not treated, and would probably be fatal in a few months. “Myeloid” refers to the type of cell this leukemia starts from.

Most cases of AML develop from cells that would turn into white blood cells (other than lymphocytes), but some cases of AML develop in other types of blood-forming cells. The different types of AML are listed in How is Acute Myeloid Leukemia Classified?

AML starts in the bone marrow (the soft inner part of certain bones, where new blood cells are made), but in most cases it quickly moves into the blood. It can sometimes spread to other parts of the body including the lymph nodes, liver, spleen, central nervous system (brain and spinal cord), and testicles.

Other types of cancer can start in these organs and then spread to the bone marrow. But these cancers that start elsewhere and then spread to the bone marrow are not leukemias.

Normal bone marrow, blood, and lymphoid tissue

To understand the different types of leukemia, it helps to know about the blood and lymph systems.

Bone marrow

Bone marrow is the soft inner part of some bones such as the skull, shoulder blades, ribs, pelvic (hip) bones, and backbones. The bone marrow is made up of a small number of blood stem cells, more mature blood-forming cells, fat cells, and supporting tissues that help cells grow.

Inside the bone marrow, blood stem cells develop into new blood cells. During this process, the cells become either lymphocytes (a kind of white blood cell) or other blood-forming cells, which are types of myeloid cells. These other blood-forming cells can develop into red blood cells, white blood cells (other than lymphocytes), or platelets.

Types of blood cells

Red blood cells carry oxygen from the lungs to all other tissues in the body, and take carbon dioxide back to the lungs to be removed. Having too few red blood cells in the body (called anemia) can make you feel tired, weak, and short of breath because your body tissues are not getting enough oxygen.

Platelets are actually cell fragments made by a type of bone marrow cell called the megakaryocyte. Platelets are important in stopping bleeding. They help plug up holes in blood vessels caused by cuts or bruises. Having too few platelets (called thrombocytopenia) may cause you to bleed or bruise easily.

White blood cells help the body fight infections. Having too few white blood cells weakens your immune system and can make you more likely to get an infection.

Types of white blood cells

Lymphocytes are mature, infection-fighting cells that develop from lymphoblasts, a type of blood stem cell in the bone marrow. Lymphocytes are the main cells that make up lymphoid tissue, a major part of the immune system. Lymphoid tissue is found in lymph nodes, the thymus (a small organ behind the breast bone), the spleen, the tonsils and adenoids, and is scattered throughout the digestive and respiratory systems and the bone marrow. There are 2 main types of lymphocytes:

• B lymphocytes (B cells) protect the body from invading germs by developing (maturing) into plasma cells, which make proteins called antibodies. The antibodies attach to the germs (bacteria, viruses, and fungi), which helps other types of white blood cells recognize and destroy them.
• T lymphocytes (T cells) can recognize cells infected by viruses and directly destroy these cells. They also help regulate the immune response.

Granulocytes are mature, infection-fighting cells that develop from myeloblasts, a type of blood-forming cell in the bone marrow. Granulocytes have granules that show up as spots under the microscope. These granules contain enzymes and other substances that can destroy germs, such as bacteria. The 3 types of granulocytes – neutrophils, basophils, and eosinophils – are distinguished by the size and color of their granules.

Monocytes develop from blood-forming monoblasts in the bone marrow and are related to granulocytes. After circulating in the bloodstream for about a day, monocytes enter body tissues to become macrophages, which can destroy some germs by surrounding and digesting them. Macrophages also help lymphocytes recognize germs and make antibodies to fight them.

Any of the blood-forming myeloid or lymphoid cells from bone marrow can turn into a leukemia cell. Once this change takes place, the leukemia cells no longer mature in a normal way. Leukemia cells often reproduce quickly, but in most cases the problem is that they don’t die when they should. They survive and build up in the bone marrow. Over time, these cells spill into the bloodstream and spread to other organs, where they can keep other cells in the body from doing their jobs.

Types of leukemia

Not all leukemias are the same. There are 4 main types of leukemia. Knowing the specific type helps doctors better predict each patient’s prognosis (outlook) and select the best treatment.

Acute leukemia versus chronic leukemia

The first factor in classifying a patient’s leukemia is whether most of the abnormal cells look like normal white blood cells (mature) or look more like stem cells (immature).

In acute leukemia, the leukemia cells are immature blood cells (called blasts). These leukemias are fast growing because normal blast cells divide quickly. But the leukemia cells don’t divide any more often than normal blast cells do. They just don’t stop dividing when normal blast cells would. Without treatment, most patients with acute leukemia would live only a few months. Some types of acute leukemia respond well to treatment, and many patients can be cured. Other types of acute leukemia have a less favorable outlook.

In chronic leukemia, the leukemia cells are more mature cells, but they are not completely normal. They generally don’t fight infection as well as normal white blood cells. And they survive longer, build up, and crowd out normal cells. Chronic leukemias tend to progress over a longer period of time, and most patients can live with them for many years. But chronic leukemias are generally harder to cure than acute leukemias.

Myeloid leukemia versus lymphocytic leukemia

The other main factor in classifying leukemia is the type of bone marrow cells that are affected.

Myeloid leukemias start in immature forms of myeloid cells – white blood cells (other than lymphocytes), red blood cells, or platelet-making cells (megakaryocytes). They are also known as myelocytic, myelogenous, or non-lymphocytic leukemias.

Lymphocytic leukemias start in immature forms of lymphocytes. They are also known as lymphoid or lymphoblastic leukemias. Lymphomas are also cancers that start in lymphocytes. But whereas lymphocytic leukemias develop from cells in the bone marrow, lymphomas develop from cells in lymph nodes or other organs.

By considering whether leukemias are acute or chronic and whether they are myeloid or lymphocytic, they can be divided into 4 main types:

• Acute myeloid (or myelogenous) leukemia (AML)
• Chronic myeloid (or myelogenous) leukemia (CML)
• Acute lymphocytic (or lymphoblastic) leukemia (ALL)
• Chronic lymphocytic leukemia (CLL)

The rest of this document focuses on acute myeloid leukemias in adults only. Chronic leukemias in adults and acute lymphocytic leukemia (ALL) in adults are discussed in other American Cancer Society documents. For information on AML in children, see Childhood Leukemia.

Researchers are now studying the causes, diagnosis, supportive care, and treatment of acute myeloid leukemia (AML) at many medical centers, university hospitals, and other institutions.

Genetics of leukemia

Scientists are making great progress in understanding how changes in the DNA inside normal bone marrow cells can cause them to develop into leukemia cells. A greater understanding of the genes (regions of the DNA) involved in certain chromosomal translocations or other changes that often occur in AML is providing insight into why these cells become abnormal. As researchers have found more of these changes, it is becoming clear that there are many types of AML. Each of these might have different gene changes that affect how the leukemia will progress and which treatments might be most helpful. Doctors are now learning how to use these changes to help them determine a person’s outlook and whether they should receive more or less intensive treatment.

In the future, this information may also be used to help develop newer targeted therapies against AML (see below).

Detecting minimal residual disease

Progress in understanding the DNA changes in AML cells has already provided highly sensitive tests for detecting the smallest amount of leukemia left after treatment (minimal residual disease), even when so few leukemia cells are present that they can’t be found by routine bone marrow tests.

For example, the polymerase chain reaction (PCR) test can identify even very small numbers of AML cells in a sample based on their gene translocations or rearrangements. A PCR test can be useful in determining how completely the treatment has destroyed the AML cells.

Doctors are now trying to determine what effect minimal residual disease has on a patient’s outlook, and how this might affect the need for further or more intensive treatment.

Improving treatment

Many studies are being done to find more effective and safer treatments for AML.

Chemotherapy

Researchers are looking to find the most effective combination of chemotherapy (chemo) drugs while still avoiding unwanted side effects. This is especially important in older patients, who are less likely to benefit from current treatments.

Researchers are studying many new chemo drugs for use in AML, including:

• Sapacitabine, a type of drug known as a nucleoside analog, which has shown promise as a treatment option for older patients with AML
• Laromustine, a type of chemo drug known as an alkylating agent, which is also being tested as an option for in older adults with AML
• Tipifarnib, a newer type of drug known as a farnesyl transferase inhibitor, which has also shown promise in early studies. This and similar drugs are now being tested in larger clinical trials.
• Bortezomib (Velcade^®), a type of drug known as a proteasome inhibitor. It is helpful in treating multiple myeloma and certain types of lymphoma. A recent study looked at adding this drug to chemo for AML with promising results.

The effectiveness of chemo may be limited in some cases because the leukemia cells become resistant to it over time. Researchers are now looking at ways to prevent or reverse this resistance by using other drugs along with chemo. They are also looking at combining chemo with a number of newer types of drugs to see if this might work better.

Treating acute promyelocytic leukemia (APL)

Most patients with APL are first treated with ATRA combined with chemo. Recent research has shown that combining ATRA with arsenic trioxide is at least as good for many patients. This combination had been used before, but often only for patients who couldn’t get the standard chemo drugs. More patients may now get ATRA plus arsenic as their first treatment, allowing them to avoid some of the side effects of chemotherapy.

Stem cell transplants

Researchers continue to refine stem cell transplants to try to increase their effectiveness, reduce complications, and determine which patients are likely to be helped by this treatment. Many studies are under way to try to help determine exactly when autologous, allogeneic, and mini-transplants might best be used.

Targeted therapies

Chemo drugs can help many people with AML, but these drugs don’t always cure the disease. New targeted drugs that specifically attack some of the genetic changes seen in AML are now being developed. These drugs work differently than standard chemotherapy drugs.

In about 1 person out of 3 with AML, the leukemia cells have a mutation in the FLT3 gene. New drugs called FLT3 inhibitors, such as midostaurin (Rydapt), target cells with this gene change. This drug is now approved for use along with chemotherapy to treat people whose AML has an FLT3 mutation. Other drugs, such as quizartinib, have also shown activity against AML in early studies, especially when combined with chemotherapy. But so far, these other drugs are only available in clinical trials.

Changes in the c-KIT gene also appear to be important in some cases of AML. Drugs that target this gene, such as dasatinib (Sprycel), are already used against other types of leukemia, and are now being studied against AML.

Many new drugs that target other changes in AML cells are now being studied as well. Examples include:

• Histone deacetylase (HDAC) inhibitors, such as vorinostat (Zolinza) and panobinostat (Farydak)
• Polo-like kinase (Plk) inhibitors, such as volasertib
• Aurora kinase inhibitors, such as AZD1152

Immunotherapy

The goal of immunotherapy is to boost the body’s immune system to help fight off or destroy cancer cells.

Monoclonal antibodies: These are man-made versions of immune system proteins (antibodies) that are designed to attach to specific targets, such as substances on the surface of cancer cells. Some work by boosting the body’s immune response against the cancer cells. Others have radioactive chemicals or cell poisons attached to them. When they are injected into the patient, these antibodies act like a homing device, bringing the radioactivity or poison directly to the cancer cells, which kills them. Monoclonal antibodies are often used to treat lymphomas, but their use in leukemias has been more limited.

Gemtuzumab ozogamicin (Mylotarg) is a monoclonal antibody with a cell poison attached to it. It is now approved to treat AML in some patients, after showing promise in clinical trials.

Immune checkpoint inhibitors: An important part of the immune system is its ability to keep itself from attacking other normal cells in the body. To do this, it uses “checkpoints” – molecules on immune cells that need to be turned on (or off) to start an immune response. Cancer cells sometimes use these checkpoints to avoid being attacked by the immune system. But newer drugs that target these checkpoints hold a lot of promise as treatments. Some of these drugs are already being used to treat other types of cancer, and they are now being studied for use in AML as well.

Vaccine therapy: Scientists are studying ways to boost the immune reaction against leukemia cells by using vaccines. For example, in one vaccine, certain types of white blood cells (cells of the immune system) are removed from the patient’s blood and exposed to a protein found on many AML cells called Wilms’ tumor 1 protein (WT1). These cells are then given back to the patient by infusion into a vein (IV). In the body, these cells help other immune system cells to attack the leukemia. An early study of this vaccine showed promising results, but more research is needed to see if it will be useful. Other vaccines are being studied as well.

CAR T-cell therapy: This is a promising new way to get the immune system to fight leukemia. For this technique, immune cells called T cells are removed from the patient’s blood and altered in the lab so they have specific substances (called chimeric antigen receptors, or CARs) that will help them attach to leukemia cells. The T cells are then grown in the lab and infused back into the patient’s blood, where they can now seek out the leukemia cells and attack them.

This technique has shown very promising results in early clinical trials against some advanced, hard-to-treat types of lymphocytic leukemias. Although it’s not yet clear if it will work against AML, clinical trials are now in progress to find out. One concern with this treatment is that some people have had very serious side effects, including very high fevers and dangerously low blood pressure in the days after it’s given. Doctors are learning how to manage these side effects.

Certain signs and symptoms might suggest that a person could have acute myeloid leukemia (AML), but tests are needed to confirm the diagnosis.

Medical history and physical exam

If signs or symptoms suggest you might have leukemia, the doctor will want to get a thorough medical history, including how long you have had symptoms and whether or not you have any risk factors.

During the physical exam, the doctor will likely pay close attention to your eyes, mouth, skin, lymph nodes, liver, spleen, and nervous system, and will look for areas of bleeding or bruising, or possible signs of infection.

If there is reason to think there might be problems caused by abnormal blood cells (anemia, infections, bleeding or bruising, etc.), you will get tests to check your blood cell counts. You might also be referred to a hematologist, a doctor who specializes in diseases of the blood (including leukemia).

Types of samples used to test for acute myeloid leukemia

If signs and symptoms and/or the results of the physical exam suggest you might have leukemia, the doctor will need to check samples of cells from your blood and bone marrow to be sure. Other tissue and cell samples may also be taken in order to help guide treatment.

Blood samples

Blood samples for tests for AML are generally taken from a vein in the arm.

Bone marrow samples

Bone marrow samples are obtained from 2 tests that are usually done at the same time:

• Bone marrow aspiration
• Bone marrow biopsy

The samples are usually taken from the back of the pelvic (hip) bone, but sometimes other bones are used instead. If only an aspiration is to be done, it may be taken from the sternum (breast bone).

In bone marrow aspiration, you lie on a table (either on your side or on your belly). The doctor will clean the skin over the hip and then numb the area and the surface of the bone by injecting a local anesthetic. This may cause a brief stinging or burning sensation. A thin, hollow needle is then inserted into the bone, and a syringe is used to suck out a small amount of liquid bone marrow. Even with the anesthetic, most patients still 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. This causes a feeling of pressure and may also cause some brief pain. Once the biopsy is done, pressure will be applied to the site to help prevent bleeding.

These bone marrow tests are used to help diagnose leukemia, but they are also repeated later to tell if the leukemia is responding to treatment.

Spinal fluid

The cerebrospinal fluid (CSF) is the liquid that surrounds the brain and spinal cord. AML can sometimes spread to the area around the brain and spinal cord. To check for this spread, doctors remove a sample of CSF for testing. The procedure used to remove this fluid is called a lumbar puncture (spinal tap). A lumbar puncture is not often used to test for AML, unless the patient is having symptoms that could be caused by leukemia cells spreading into the brain and spinal cord.

For this test, the patient may lie on his side or sit up. The doctor first numbs an area of skin on the lower part of the back over the spine. A small, hollow needle is then inserted between the bones of the spine into the area around the spinal cord to withdraw some of the fluid. A lumbar puncture is sometimes used to deliver chemotherapy drugs into the CSF to help prevent or treat the spread of leukemia to the spinal cord and brain.

Lab tests used to diagnose and classify acute myeloid leukemia

One or more of the following lab tests may be done on the samples to diagnose AML and/or to determine the specific subtype of AML.

Complete blood count and peripheral blood smear

The complete blood count (CBC) is a test that measures the amounts of different cells in the blood, such as the red blood cells, white blood cells, and platelets. This test is often done along with a differential (or diff), which looks at the numbers of the different types of white blood cells. For the peripheral blood smear, a sample of blood is looked at under the microscope. Changes in the numbers and the appearance of different types of blood cells often help diagnose leukemia.

Most patients with AML have too many immature white cells in their blood, and not enough red blood cells or platelets. Many of the white blood cells may be myeloblasts (often just called blasts), which are immature blood-forming cells that are not normally found in the blood. These immature cells don’t work like normal, mature white blood cells. These findings may suggest leukemia, but the disease usually is not diagnosed without looking at a sample of bone marrow cells.

Blood chemistry and coagulation tests

These tests measure the amounts of certain chemicals in the blood and the ability of the blood to clot. These tests are not used to diagnose leukemia, but they can help detect liver or kidney problems, abnormal levels of certain minerals in the blood, or problems with blood clotting.

Routine microscopic exams

Samples of blood, bone marrow, or CSF are looked at under a microscope by a pathologist (a doctor specializing in lab tests) and may be reviewed by the patient’s hematologist/oncologist (a doctor specializing in cancer and blood diseases).

The doctors will look at the size, shape, and other traits of the white blood cells in the samples to classify them into specific types.

A key element is whether the cells look mature (like normal blood cells) or immature (lacking features of normal blood cells). The most immature cells are called myeloblasts (or blasts for short).

The percentage of blasts in the bone marrow or blood is particularly important. Having at least 20% blasts in the marrow or blood is generally required for a diagnosis of AML. It can also be diagnosed if the blasts are found (using another test) to have a chromosome change that occurs only in a specific type of AML, even if the blast percentage doesn’t reach 20%. Sometimes the blasts look like normal immature cells in the bone marrow. But in normal bone marrow, the blast count is 5% or less.

Sometimes just counting and looking at the cells isn’t enough to provide a clear diagnosis. Additional tests may be used to confirm the diagnosis of AML.

Cytochemistry

For cytochemistry tests, cells are exposed to chemical stains (dyes) that react with only some types of leukemia cells. These stains cause color changes that can be seen under a microscope, which can help the doctor determine what types of cells are present. For instance, one stain can help distinguish AML cells from acute lymphocytic leukemia (ALL) cells. The stain causes the granules of most AML cells to appear as black spots under the microscope, but it does not cause ALL cells to change colors.

Flow cytometry and immunohistochemistry

Flow cytometry is often used to look at the cells from bone marrow and blood samples. It is very helpful in determining the exact type of leukemia.

The test looks for certain substances on the surface of cells that help identify what types of cells they are. A sample of cells is treated with special antibodies (man-made immune system proteins) that stick to the cells only if they have these substances. The cells are then passed in front of a laser beam. If the cells now have antibodies attached to them, the laser will make them give off light, which can be measured and analyzed by a computer. Groups of cells can be separated and counted by these methods.

In immunohistochemistry tests, cells from the blood or bone marrow samples are also treated with special antibodies. But instead of using a laser and computer, the sample is treated so that certain types of cells change color when seen under a microscope.

These tests are used for immunophenotyping – classifying leukemia cells according to the substances (antigens) on their surfaces. Leukemia cells can have different antigens depending on which type of cells they start in and how mature they are, and this information can be helpful in AML classification.

Cytogenetics

For this test, a cell’s chromosomes (long strands of DNA) are looked at under a microscope. Normal human cells contain 23 pairs of chromosomes, each of which are a certain size and stain a certain way. In some cases of AML, the cells have chromosome changes that can be seen under a microscope.

For instance, 2 chromosomes may swap some of their DNA, so that part of one chromosome becomes attached to part of a different chromosome. This change, called a translocation, can usually be seen under a microscope. Other types of chromosome changes are also possible (see below). Recognizing these changes can help identify certain types of AML and can be important in determining a patient’s outlook.

It usually takes about 2 to 3 weeks to get results for this test because the leukemia cells must be grown in lab dishes for a couple of weeks before their chromosomes can be looked at under the microscope.

The results of cytogenetic testing are written in a shorthand form that describes the chromosome changes:

• A translocation, written as t(8;21), for example, means a part of chromosome 8 is now located on chromosome 21, and vice versa.
• An inversion, written as inv(16), for example, means that part of the chromosome 16 is now in reverse order but is still attached to the chromosome.
• A deletion, written as del(7) or -7, for example, indicates part of chromosome 7 has been lost.
• An addition or duplication, +8, for example, means that all or part of chromosome 8 has been duplicated, and too many copies of it are found within the cell.

Not all chromosome changes can be seen under a microscope. Other lab tests can often detect these changes.

Fluorescent in situ hybridization (FISH)

This is similar to cytogenetic testing. It uses special fluorescent dyes that only attach to specific genes or parts of particular chromosomes. FISH can find the chromosome changes (such as translocations) that are visible under a microscope in standard cytogenetic tests, as well as some changes too small to be seen with usual cytogenetic testing.

FISH can be used to look for changes in specific genes or parts of chromosomes. It can be used on regular blood or bone marrow samples without growing them in a lab first. This means the results are often available more quickly than with regular cytogenetic testing. The drawback is that it only looks for certain gene or chromosome changes, so the doctor has to know what he or she is looking for before the test is run.

Polymerase chain reaction (PCR)

This is a very sensitive test that can also find some gene and chromosome changes too small to be seen under a microscope. It is helpful in finding gene changes that are in only a few cells, making it good for finding small numbers of leukemia cells in a sample (like after treatment). Like FISH, this test only looks for certain gene or chromosome changes, so the doctor has to know what he or she is looking for before the test is run.

Imaging tests for acute myeloid leukemia

Imaging tests use x-rays, sound waves, magnetic fields, or radioactive particles to create pictures of the inside of the body. Leukemia doesn’t usually form tumors, so imaging tests are not often helpful in making the diagnosis. When imaging tests are done in people with AML, it is most often to look for infections or other problems, rather than to look for the leukemia itself. In a few cases, imaging tests may be done to help determine the extent of the disease, if it is thought it may have spread beyond the bone marrow and blood.

X-rays

Routine chest x-rays may be done if a lung infection is suspected.

Computed tomography (CT) scan

This test can help show if any lymph nodes or organs in your body are enlarged. It isn’t usually needed to diagnose AML, but it may be done if your doctor suspects the leukemia is growing in an organ, like your spleen.

The CT scan uses x-rays to make detailed, cross-sectional images of your body. Unlike a regular x-ray, CT scans can show the detail in soft tissues (such as internal organs).

Before the test, you may be asked to drink a contrast solution and/or get an intravenous (IV) injection of a contrast dye that helps better outline abnormal areas in the body. You may need an IV line through which the contrast dye is injected. Injecting contrast dye can cause a feeling of flushing or warmth, in the face or elsewhere. Some people get hives or, rarely, more serious allergic reactions like trouble breathing and low blood pressure. Be sure to tell the doctor if you have any allergies or have ever had a reaction to any contrast material used for x-rays.

A CT scanner has been described as a large donut, with a narrow table that slides in and out of the middle opening. You need to lie still on the table while the scan is being done. CT scans take longer than regular x-rays, and you might feel a bit confined by the ring while the pictures are being taken.

CT-guided needle biopsy: In some cases, a CT can be used to guide a biopsy needle into a suspected abnormality, such as an abscess. For this procedure, you lie on the CT scanning table while the doctor moves a biopsy needle through the skin and toward the mass. CT scans are repeated until the needle is within the mass. A sample is then removed and sent to the lab to be looked at under a microscope.

PET/CT: Some machines combine the CT scan with a PET scan (PET/CT scan). For a PET scan, glucose (a form of sugar) containing a radioactive atom is injected into the blood. Because cancer cells in the body grow rapidly, they absorb large amounts of the radioactive sugar. A special camera can then create a picture of areas of radioactivity in the body. With a PET/CT scan, the doctor can compare areas of higher radioactivity on the PET scan with the more detailed appearance of that area on the CT.

Magnetic resonance imaging (MRI) scan

Like CT scans, MRI scans make detailed images of soft tissues in the body. But MRI scans use radio waves and strong magnets instead of x-rays. A contrast material is often injected into a vein before the scan to better see details. This contrast is not the same as the contrast used for CT scans, but allergic reactions can still occur.

MRI scans are very helpful in looking at the brain and spinal cord, but they are not usually needed in people with AML.

MRI scans take longer than CT scans – often up to an hour. You might have to lie inside a narrow tube, which is confining and can be distressing to some people. Newer, more open MRI machines may be another option. The MRI machine makes loud buzzing and clicking noises that you may find disturbing. Some places give you headphones or earplugs to help block this noise out.

Ultrasound

Ultrasound uses sound waves and their echoes to make pictures of internal organs or masses.

Ultrasound can be used to look at lymph nodes near the surface of the body or to look inside your abdomen for enlarged lymph nodes or organs such as the liver, spleen, and kidneys. (It can’t be used to look inside the chest because the ribs block the sound waves.) It is sometimes used to help guide a biopsy needle into an enlarged lymph node.

For this test, a small, microphone-like instrument called a transducer is usually placed on the skin over the area to be examined (the skin is first lubricated with gel). It gives off sound waves and picks up the echoes as they bounce off the organs. The echoes are converted by a computer into an image on a computer screen.

This is an easy test to have, and it uses no radiation. For most scans, you simply lie on a table, and a technician moves the transducer over the part of your body being looked at.

Acute myeloid leukemia (AML) can cause many different signs and symptoms. Some are more common with certain subtypes of AML.

General symptoms

Patients with AML often have several non-specific (general) symptoms. These can include:

• Weight loss
• Fatigue
• Fever
• Night sweats
• Loss of appetite

Of course, these are not just symptoms of AML, and more often are caused by something other than leukemia.

Problems caused by low numbers of blood cells

Many signs and symptoms of AML result from a shortage of normal blood cells, which happens when the leukemia cells crowd out the normal blood-making cells in the bone marrow. As a result, people do not have enough normal red blood cells, white blood cells, and blood platelets. These shortages show up on blood tests, and they can also cause symptoms.

Symptoms from low red blood cell counts (anemia): Red blood cells carry oxygen to all of the cells in the body. A shortage of red blood cells can cause:

• Tiredness (fatigue)
• Weakness
• Feeling cold
• Feeling dizzy or lightheaded
• Headaches
• Shortness of breath

Symptoms from low white blood cell counts: Infections can occur because of a shortage of normal white blood cells (called leukopenia) or a shortage of normal neutrophils (called neutropenia). Neutrophils are a type of white blood cell needed to fight infections from bacteria. Patients with AML can get infections that don’t seem to go away or may get one infection after another. Fever often goes along with the infection.

Although people with AML may have high white blood cell counts due to excess numbers of leukemia cells, these cells don’t protect against infection the way normal white blood cells do.

Symptoms from low blood platelet counts: Platelets in the blood normally help stop bleeding. A shortage of blood platelets (called thrombocytopenia) can lead to:

• Excess bruising and bleeding
• Frequent or severe nosebleeds
• Bleeding gums

Symptoms caused by high numbers of leukemia cells

The cancer cells in AML (called blasts) are bigger than normal white blood cells and have more trouble going through tiny blood vessels. If the blast count gets very high, these cells can clog up blood vessels and make it hard for normal red blood cells (and oxygen) to get to tissues. This is called leukostasis. Leukostasis is rare, but it is a medical emergency that needs to be treated right away. Some of the symptoms are like those seen with a stroke, and include:

• Headache
• Weakness in one side of the body
• Slurred speech
• Confusion
• Sleepiness

When blood vessels in the lungs are affected, patients have problems with shortness of breath. Blood vessels in the eye can be affected as well, leading to blurry vision or even loss of vision.

Bleeding and clotting problems

Patients with a certain type of AML called acute promyelocytic leukemia (APL) might go to the doctor with problems with bleeding and clotting. They may have a nose bleed that won’t stop, or a cut that won’t stop oozing. They may also have calf swelling from a blood clot called a deep venous thrombosis (DVT) or chest pain and shortness of breath from a blood clot in the lung (called a pulmonary embolism or PE).

Bone or joint pain

Some patients have bone pain or joint pain caused by the buildup of leukemia cells in these areas.

Swelling in the abdomen

Leukemia cells may collect in the liver and spleen, causing them to enlarge. This may be noticed as a fullness or swelling of the belly. The lower ribs usually cover these organs, but when they are enlarged the doctor can feel them.

Spread to the skin

If leukemia cells spread to the skin, they can cause lumps or spots that may look like common rashes. A tumor-like collection of AML cells under the skin or other parts of the body is called a chloroma, granulocytic sarcoma, or myeloid sarcoma. Rarely, AML can first appear as only a chloroma with no leukemia cells in the bone marrow.

Spread to the gums

Certain types of AML may spread to the gums, causing swelling, pain, and bleeding.

Spread to other organs

Sometimes, leukemia cells can spread to other organs. Spread to the brain and spinal cord can cause symptoms such as:

• Headaches
• Weakness
• Seizures
• Vomiting
• Trouble with balance
• Facial numbness
• Blurred vision

On rare occasions AML can spread to the eyes, testicles, kidneys, or other organs.

Enlarged lymph nodes

In rare cases, AML can spread to lymph nodes (bean-sized collections of immune cells throughout the body), causing them to get bigger. Affected nodes in the neck, groin, underarm areas, or above the collarbone may be felt as lumps under the skin.

Although any of the symptoms and signs above may be caused by AML, they can also be caused by other conditions. Still, if you have any of these problems, it’s important to see a doctor so the cause can be found and treated, if needed.

The American Cancer Society’s estimates for leukemia in the United States for 2018 are:

• About 60,300 new cases of leukemia (all kinds) and 24,370 deaths from leukemia (all kinds)
• About 19,520 new cases of acute myeloid leukemia (AML). Most will be in adults.
• About 10,670 deaths from AML. Almost all will be in adults.

Acute myeloid leukemia is generally a disease of older people and is uncommon before the age of 45. The average age of a patient with AML is about 68 years.

AML is slightly more common among men than among women, but the average lifetime risk in both sexes is a little less than ½ of 1%.

Information on treatment success rates for AML in adults can be found in Treatment response rates for acute myeloid leukemia.

Visit the American Cancer Society’s Cancer Statistics Center for more key statistics.

A risk factor is something that affects your chance of getting a disease, such as cancer. Different cancers have different risk factors. Some risk factors, like smoking, can be changed. Others, like a person’s age or family history, can’t be changed.

But having a risk factor, or even several risk factors, does not mean that you definitely will get the disease. And many people who get the disease may have few or no known risk factors. Even if a person has a risk factor and develops cancer, it’s often very hard to know how much that risk factor contributed to the cancer.

There are some known risk factors for acute myeloid leukemia (AML).

Smoking

The only proven lifestyle-related risk factor for AML is smoking. Many people know that smoking is linked to cancers of the lungs, mouth, throat, and larynx (voice box), but few realize that it can also affect cells that don’t come into direct contact with smoke. Cancer-causing substances in tobacco smoke are absorbed by the lungs and spread through the bloodstream to many parts of the body.

Certain chemical exposures

The risk of AML is increased by exposure to certain chemicals.

For example, long-term exposure to high levels of benzene is a risk factor for AML. Benzene is a solvent used in the rubber industry, oil refineries, chemical plants, shoe manufacturing, and gasoline-related industries, and is also found in cigarette smoke, gasoline and motor vehicle exhaust, and some glues, cleaning products, detergents, art supplies, and paints.

Some studies have linked heavy workplace exposure to formaldehyde with AML risk, but this link has not been seen in some other studies.

Certain chemotherapy drugs

Patients with cancer who are treated with certain chemotherapy (chemo) drugs are more likely to develop AML.

Drugs called alkylating agents and platinum agents are linked to an increased risk of AML that peaks about 8 years after chemo. Often a patient will get a disease called myelodysplastic syndrome before the AML. Examples of alkylating agents include cyclophosphamide, mechlorethamine, procarbazine, chlorambucil, melphalan, busulfan, and carmustine. Platinum drugs include cisplatin and carboplatin.

Chemo drugs known as topoisomerase II inhibitors are also linked to AML. AML linked to these drugs tends to occur only a few years after treatment and without myelodysplastic syndrome developing first. Examples of topoisomerase II inhibitors include etoposide, teniposide, mitoxantrone, epirubicin, and doxorubicin.

For more information, see Second Cancers in Adults.

Radiation exposure

High-dose radiation exposure (such as being a survivor of an atomic bomb blast or nuclear reactor accident) increases the risk of developing AML. Japanese atomic bomb survivors had a greatly increased risk of developing acute leukemia, most often about 6 to 8 years after exposure.

Radiation treatment for cancer has also been linked to an increased risk of AML. The risk varies based on the amount of radiation given and what area is treated, but is not as high as was seen after the atomic bomb blasts.

The possible risks of leukemia from exposure to lower levels of radiation, such as from imaging tests like x-rays or CT scans, are not well-defined. If a fetus is exposed to radiation within the first months of development, it may carry an increased risk of leukemia, but the extent of the risk is not clear. If there is an increased risk it is likely to be small, but to be safe, most doctors try to limit radiation exposure from tests as much as possible, especially in children and pregnant women.

For more information, see X-rays, Gamma Rays and Cancer Risk.

Certain blood disorders

People with certain blood disorders seem to be at increased risk for getting AML. These include chronic myeloproliferative disorders such as polycythemia vera, essential thrombocythemia, and idiopathic myelofibrosis. The risk of AML is increased further if treatment for these disorders includes some types of chemotherapy or radiation.

Some people who have myelodysplastic syndrome (MDS) may develop AML. Patients with MDS have low blood cell counts and abnormal cells in the blood and bone marrow. MDS can evolve over time into AML. Patients who develop AML after having MDS typically have a poor prognosis.

Genetic syndromes

Some syndromes that are caused by genetic mutations (abnormal changes) present at birth seem to raise the risk of AML. These include:

• Fanconi anemia
• Bloom syndrome
• Ataxia-telangiectasia
• Diamond-Blackfan anemia
• Schwachman-Diamond syndrome
• Li-Fraumeni syndrome
• Neurofibromatosis type 1
• Severe congenital neutropenia (also called Kostmann syndrome)

Some chromosome problems present at birth are also linked to a higher risk of AML, including:

• Down syndrome (being born with an extra copy of chromosome 21)
• Trisomy 8 (being born with an extra copy of chromosome 8)

Family history

Although most cases of AML are not thought to have a strong genetic link, having a close relative (such as a parent or sibling) with AML increases your risk of getting the disease.

Someone who has an identical twin who got AML before they were a year old has a very high risk of also getting AML.

Older age

AML can occur at any age, but it becomes more common as people get older.

Male gender

AML is more common in males than in females. The reason for this is not clear.

Uncertain, unproven or controversial risk factors

Other factors that have been studied for a possible link to AML include:

• Exposure to electromagnetic fields (such as living near power lines)
• Workplace exposure to diesel, gasoline, and certain other chemicals and solvents
• Exposure to herbicides or pesticides

So far, none of these factors has been linked conclusively to AML. Research in these areas is ongoing.

Some people with acute myeloid leukemia (AML) have one or more known risk factors (see What are the risk factors for acute myeloid leukemia?), but many do not. Even when a person has one or more risk factors, there is no way to tell if it actually caused the cancer.

Scientists have learned how certain changes in DNA can cause normal bone marrow cells to become leukemia cells. Normal human cells grow and function based on the information contained in each cell’s chromosomes. Chromosomes are long strands of DNA. The DNA inside our cells makes up our genes – the instructions for how our cells function. We tend to look like our parents because they are the source of our DNA. But our genes affect more than how we look.

Some genes control when our cells grow, divide to make new cells, and die at the right time. Certain genes that help cells grow, divide, or live longer are called oncogenes. Others that slow down cell division or make cells die at the right time are called tumor suppressor genes.

Each time a cell prepares to divide into 2 new cells, it must make a new copy of the DNA in its chromosomes. This process is not perfect, and errors can occur that affect genes within the DNA. Cancers can be caused by DNA mutations (changes) that turn on oncogenes or turn off tumor suppressor genes. For instance, changes in certain genes such as FLT3, c-KIT, and RAS are common in AML cells. These types of changes can help cells grow out of control.

Mutations in specific genes are found in many cases of AML, but larger changes in one or more chromosomes are also common. Even though these changes involve larger pieces of DNA, their effects are still likely to be due to changes in just one or a few genes that are on that part of the chromosome. Several types of chromosome changes may be found in AML cells:

• Translocations are the most common type of DNA change that can lead to leukemia. A translocation means that a part of one chromosome breaks off and becomes attached to a different chromosome. The point at which the break occurs can affect nearby genes – for example, it can turn on oncogenes or turn off genes like RUNX1and RARa, which would normally help blood cells to mature.
• Deletions occur when part of a chromosome is lost. This can result in the cell losing a gene that helped keep its growth in check (a tumor suppressor gene).
• Inversions occur when part of a chromosome gets turned around, so it’s now in reverse order. This can result in the loss of a gene (or genes) because the cell can no longer read its instructions (much like trying to read a book backwards).
• Addition or duplication means that there is an extra chromosome or part of a chromosome. This can lead to too many copies of certain genes within the cell. This can be a problem if one or more of these genes are oncogenes.

Different cases of AML can have different chromosome changes, and some changes are more common than others. Doctors are trying to figure out why these changes occur and how each of them might lead to leukemia. For example, some are more common in leukemia that occurs after chemotherapy for another cancer.

Some changes seem to have more of an effect on a person’s prognosis (outlook) than others. For instance, they may affect how quickly the leukemia cells grow, or how likely they are to respond to treatment. This is discussed in more detail in  How is acute myeloid leukemia classified?

Some people with certain types of cancer have inherited DNA mutations from a parent that increase their risk for the disease. Although this can happen in some cases of AML, such as in the genetic syndromes discussed in the What are the risk factors for acute myeloid leukemia?, inherited mutations are not often a cause in AML.

Most DNA changes related to AML occur during a person’s lifetime, rather than having been inherited before birth. Some of these acquired changes may have outside causes like radiation or cancer-causing chemicals, but in most cases the reason they occur is not known. They seem to happen more often as we age, which might help explain why AML usually occurs in older people.

It’s not clear what causes most cases of acute myeloid leukemia (AML). Since most people with AML don’t have risk factors that can be changed, at the present time there is no known way to prevent most cases of AML.

Smoking is by far the most significant controllable risk factor for AML, and quitting offers the greatest chance to reduce a person’s risk of AML. Of course, non-smokers are also much less likely than smokers to develop many other cancers, as well as heart disease, stroke, and some other diseases.

Treating some other cancers with chemotherapy and radiation may cause secondary (post-treatment) leukemias. Doctors are trying to figure out how to treat these cancers without raising the risk of secondary leukemia. But for now, the obvious benefits of treating life-threatening cancers with chemotherapy and radiation must be balanced against the small chance of getting leukemia years later.

Avoiding known cancer-causing chemicals, such as benzene, can lower the risk of getting AML. But most experts agree that exposure to workplace and environmental chemicals seems to account for only a small portion of leukemia cases.

For many types of cancer, finding the cancer early makes it easier to treat. The American Cancer Society recommends screening tests for early detection of certain cancers in people without any symptoms.

But at this time, there are no special tests recommended to find acute myeloid leukemia (AML) early. The best way to find leukemia early is to report any possible symptoms of leukemia to the doctor right away.

Some people are known to be at increased risk of AML because they have certain blood disorders (such as myelodysplastic syndrome) or inherited disorders (such as Down syndrome), or because they were treated with certain chemotherapy drugs or radiation. Most doctors recommend that these people get careful, regular medical checkups. These people don’t usually develop leukemia, but they and their doctors should be familiar with the possible symptoms of AML.

For some people with acute myeloid leukemia (AML), treatment can destroy the leukemia cells. Completing treatment can be both stressful and exciting. You may be relieved to finish treatment, but find it hard not to worry about the leukemia coming back. (When leukemia comes back after treatment, it is called recurrence.) This is a very common concern in people who have had cancer.

It may take a while before your fears lessen. But it may help to know that many leukemia survivors have learned to live with this uncertainty and are leading full lives. See Understanding Recurrence for more about this.

For other people, the leukemia may never go away completely. These people may get regular treatments with chemotherapy or other therapies to try to help keep the leukemia under control and help relieve symptoms from it. Learning to live with leukemia that does not go away can be difficult and very stressful. It has its own type of uncertainty. See Managing Cancer As a Chronic Illness for more about this.

Follow-up care

Treatment for acute myeloid leukemia (AML) can continue for months or years. Even after treatment ends, you will need frequent follow-up exams – probably every few months for several years. It’s very important to go to all of your follow-up appointments. During these visits, your doctor will ask about any symptoms, examine you, and get blood tests or bone marrow exams. Follow-up is needed to check for cancer recurrence, as well as possible side effects of certain treatments.

Almost any cancer treatment can have side effects. Some may last for only a short time, but others can last the rest of your life. Tell your cancer care team about any changes or problems you notice and about any concerns you have.

If the leukemia does come back, it is usually while the patient is still being treated or shortly after they have finished chemotherapy. If this happens, treatment would be as described in What if the leukemia doesn’t respond or comes back after treatment? It is unusual for AML to return if there are still no signs of the disease within a few years after treatment.

It is also very important to keep health insurance. Tests and doctor visits cost a lot, and even though no one wants to think of their cancer coming back, this could happen.

Should your cancer come back, see Understanding Recurrence for information on how to manage and cope with this phase of your treatment.

Seeing a new doctor

At some point after your treatment, you may be seeing a new doctor who doesn’t know anything about your medical history. It’s important to be able to give your new doctor the details of your diagnosis and treatment. Gathering these details soon after treatment may be easier than trying to get them at some point in the future. Make sure you have this information handy (and always keep copies for yourself):

• A copy of your pathology report(s) from any biopsies or surgeries
• If you had surgery, a copy of your operative report(s)
• If you stayed in the hospital, a copy of the discharge summary that the doctor wrote when you were sent home
• If you had radiation therapy, a copy of the treatment summary
• If you had chemotherapy or other medicines, a list of your drugs, drug doses, and when you took them
• The names and contact information of the doctors who treated your cancer