Chemotherapy for Acute Myeloid Leukemia (AML)

Chemotherapy (chemo) is the use of anti-cancer drugs that are injected into a vein, under the skin, or into the cerebrospinal fluid (CSF), or drugs that are taken by mouth to destroy or control cancer cells. Except when given into the CSF, these drugs enter the bloodstream and reach all areas of the body, making this treatment useful for cancers such as leukemia that spread throughout the body.

Chemotherapy is the main treatment for most people with acute myeloid leukemia (AML), although sometimes other treatments might be used as well.

Less intense chemo might be recommended for people with other serious health issues, but advanced age by itself is not a barrier to getting chemo.

How is chemo given?

Treatment of AML with chemo is usually in phases:

• Induction is the first phase of treatment. It is short and intensive, typically lasting about a week. The goal is to clear the blood of leukemia cells (blasts) and to reduce the number of blasts in the bone marrow to normal.
• Consolidation is chemo given after a person has recovered from induction. It is meant to kill the small number of leukemia cells that are still around but can’t be seen (because there are so few of them). For consolidation, chemo is given in cycles, with each period of treatment followed by a rest period to allow the body time to recover.
• In a third phase, called maintenance (or post-consolidation), low doses of chemo (or other treatments) are given for months or years after consolidation is finished. This is often used to treat acute promyelocytic leukemia (APL), and it is sometimes used for other types of AML as well.

Most chemo drugs used to treat AML are given into a vein (IV), usually through a central venous catheter, although some can be injected under the skin or pills taken by mouth . If there are signs that the leukemia has reached the brain or spinal cord (which is not common with AML), chemo might also be given into the CSF (known as intrathecal chemo). This can be done with a thin tube (catheter) that is put in through a small hole in the skull (such as an Ommaya reservoir), or during a lumbar puncture (spinal tap).

Most chemo regimens used to treat AML are intensive and can cause serious side effects, so treatment typically is given in the hospital.

Which chemo drugs are used to treat AML?

The chemo drugs used most often to treat AML are a combination of: 

• Cytarabine (cytosine arabinoside or ara-C) and
• An anthracycline drug, such as daunorubicin (daunomycin) or idarubicin

Other chemo drugs that may be used to treat AML include:

• Cladribine (2-CdA)
• Fludarabine
• Mitoxantrone
• Etoposide (VP-16)
• Hydroxyurea
• Corticosteroid drugs, such as prednisone or dexamethasone
• Methotrexate (MTX)
• 6-mercaptopurine (6-MP)
• Azacitidine
• Decitabine
• Liposomal daunorubicin and cytarabine (Vyxeos, CPX351)

For more on how chemo is used to treat AML, see Typical Treatment of Most Types of Acute Myeloid Leukemia (AML), Except APL.

Possible side effects of chemo

Chemo drugs can affect some normal cells in the body, which can lead to side effects. The side effects of chemo depend on the type and dose of drugs given and how long they are taken. Side effects can include:

• Hair loss
• Mouth sores
• Loss of appetite
• Nausea and vomiting
• Diarrhea or constipation

Chemo drugs also affect the normal cells in bone marrow, which can lower blood cell counts. This can lead to:

• Increased risk of infections (from too few normal white blood cells)
• Easy bruising or bleeding (from too few blood platelets)
• Fatigue and shortness of breath (from too few red blood cells)

Most side effects from chemo go away once treatment is finished. Low blood cell counts can last weeks, but then should return to normal. There are often ways to lessen these side effects. For example, drugs can be given to help prevent or reduce nausea and vomiting. Be sure to ask about medicines to help reduce side effects, and let your doctor or nurse know when you do have side effects so they can be managed.

Low white blood cell counts: Some of the most serious side effects of chemo in people with AML are caused by not having enough normal white blood cells, which increases the risk of infection.

If your white blood cell counts are very low during treatment, you can help lower your risk of infection by carefully avoiding exposure to germs. During this time, your doctor or nurse may tell you to:

• Wash your hands often.
• Avoid fresh, uncooked fruits and vegetables and other foods that might carry germs.
• Avoid fresh flowers and plants because they may carry mold.
• Make sure other people wash their hands before they come in contact with you.
• Avoid large crowds and people who are sick.

You may get antibiotics before you have signs of infection or at the earliest sign that an infection may be developing (such as a fever). You may also get drugs that help prevent viral and fungal infections.

Drugs known as growth factors, such as filgrastim (Neupogen, other names), pegfilgrastim (Neulasta, other names), and sargramostim (Leukine), are sometimes given to increase the white blood cell counts after chemo, to help lower the chance of infection. However, it’s not clear if they have an effect on treatment success.

Low platelet counts: If your platelet counts are low, you may be given drugs or platelet transfusions to help prevent bleeding.

Low red blood cell counts: Shortness of breath and extreme fatigue caused by low red blood cell counts (anemia) may be treated with drugs or with red blood cell transfusions.

Decisions about when a person can leave the hospital are often influenced by their blood counts. Some people find it helpful to keep track of their counts. If you are interested in this, ask your doctor or nurse about your blood cell counts and what these numbers mean.

Side effects of specific drugs: Certain drugs have some specific possible side effects. For example:

• High doses of cytarabine can cause dryness in the eyes and effects on certain parts of the brain, which can lead to problems with coordination or balance. The drug dose may need to be reduced or stopped altogether if these side effects appear.
• Anthracyclines (such as daunorubicin or idarubicin) can damage the heart, so they might not be used in someone who already has heart problems.

Other organs that could be damaged by chemo drugs include the kidneys, liver, testicles, ovaries, and lungs. Doctors and nurses carefully monitor treatment to limit the risk of these side effects as much as possible.

If serious side effects occur, the chemo may have to be reduced or stopped, at least for a short time. Careful monitoring and adjustment of drug doses are important because some side effects can last a long time.

Tumor lysis syndrome: This side effect of chemo can occur in people who have large numbers of leukemia cells in their body, mainly during the induction phase of treatment. When chemo kills these cells, they break open and release their contents into the bloodstream. This can overwhelm kidneys, which aren’t able to get rid of all of these substances at once. Excess amounts of certain minerals can also affect the heart and nervous system. This can be prevented by giving the patient extra fluids during treatment and by giving certain drugs, such as bicarbonate, allopurinol, and rasburicase, which help rid the body of these substances.