Acute Myeloid Leukaemia

Acute myeloid leukaemia is a rapidly progressing blood cancer that affects the bone marrow, causing it to produce abnormal white blood cells that crowd out healthy blood cells, leading to serious complications if left untreated.

AML, acute myelogenous leukemia, acute myeloblastic leukemia, acute granulocytic leukemia, acute nonlymphocytic leukemia

• Bone marrow
• Blood
• Central nervous system (brain and spinal cord)
• Skin
• Gums

Table of contents

• What is acute myeloid leukaemia?
• How common is AML?
• Types of acute myeloid leukaemia
• What causes acute myeloid leukaemia?
• Signs and symptoms
• Diagnosis and testing
• Treatment approaches
• Living with acute myeloid leukaemia

What is acute myeloid leukaemia?

Acute myeloid leukaemia is a type of cancer that affects your bone marrow (the soft, spongy tissue in the center of most bones) and blood^[1]. It is a rapidly progressing cancer characterized by the buildup of abnormal white blood cells in the bone marrow and blood^[3].

Your bone marrow normally works like an efficient production line, making the exact number of blood cells your body needs. It produces stem cells that mature into red blood cells (which carry oxygen), white blood cells (which protect against infection), and platelets (which help blood clot)^[2]. In AML, however, your bone marrow produces abnormal cells called myeloblasts or myeloid blasts^[5].

These abnormal cells don’t function like normal blood cells. As their number increases in the blood and bone marrow, there is less room for healthy platelets, red blood cells, and other white blood cells. This may lead to easy bleeding, anemia (low red blood cell count), and infection^[5]. The cancer cells can also spread outside the blood to other parts of the body, including the central nervous system, skin, and gums^[8].

How common is AML?

Acute myeloid leukaemia is the most common type of acute leukaemia in adults^[4]. It affects about 4 in 100,000 adults annually^[2]. Although AML can be diagnosed at any age, it is less common before age 45 and typically affects people age 60 and older^[4]. Each year about 1,160 children receive an AML diagnosis^[10].

Types of acute myeloid leukaemia

There are several AML subtypes. They all affect your blood cell levels, but different types cause different symptoms and respond to treatment in different ways^[2]. Medical specialists determine AML subtypes by examining cancerous cells under a microscope and looking for changes in chromosomes and mutations in certain genes^[2].

AML subtypes include^[2]:

• Myeloid leukaemia: Cancer in cells that produce neutrophils, a type of white blood cell. Most people with AML have this subtype.
• Acute monocytic leukaemia (AML-M5): Cancer in cells that produce monocytes, another type of white blood cell.
• Acute megakaryocytic leukaemia (AMLK): Cancer in cells that produce red blood cells or platelets.
• Acute promyelocytic leukaemia (APL): Cancer in promyelocytes (immature white blood cells) that prevents these cells from developing properly. This subtype occurs when genes on chromosome 15 switch places with genes on chromosome 17^[5].

What causes acute myeloid leukaemia?

Experts aren’t sure what causes acute myeloid leukaemia^[2]. They do know the condition happens when certain genes or chromosomes change (mutate), creating abnormal blood cells^[2]. These genetic changes may happen during your lifetime when something changes your DNA, if you inherited a genetic disorder that increases your risk of developing AML, or if there was a change in certain genes in your biological parents’ sperm or egg^[10].

Smoking, previous chemotherapy treatment, and exposure to radiation may increase the risk of AML^[5].

Signs and symptoms

Early on, AML symptoms may feel like you have a cold or flu that won’t go away^[2]. Acute myeloid leukaemia is aggressive, which means you quickly develop new and more noticeable symptoms^[2].

Symptoms of acute myeloid leukaemia may include^[2][4]:

• Fever
• Feeling very tired (fatigue)
• Easy bruising or bleeding, including frequent nosebleeds and bleeding gums
• Dizziness
• Feeling cold
• Night sweats
• Frequent infections or infections that don’t go away
• Headaches
• Loss of appetite
• Unexplained weight loss
• Pale skin or change in skin color
• Shortness of breath
• Swollen lymph nodes
• Weakness
• Bone, back, or abdominal pain
• Tiny red spots on your skin (called petechiae)
• Wounds or sores that don’t go away

Acute myeloid leukaemia symptoms are similar to those of many more common conditions, such as infections. If you have ongoing symptoms that worry you, make an appointment with your healthcare professional^[4].

Diagnosis and testing

Acute myeloid leukaemia diagnosis often begins with an exam that checks for bruising, bleeding in the mouth or gums, infection, and swollen lymph nodes^[12]. Tests that examine the blood and bone marrow are used to diagnose AML^[5].

Diagnostic testing includes^[12]:

• Blood tests: A complete blood count may show too many or too few white blood cells, not enough red blood cells, and not enough platelets. Another blood test looks for immature white blood cells called myeloblasts in the blood.
• Bone marrow aspiration and biopsy: A healthcare professional uses a thin needle to remove a small amount of liquid bone marrow, usually from the hip bone. A bone marrow biopsy removes a small piece of bone tissue and the enclosed marrow. Medical specialists examine these samples under a microscope.
• Flow cytometry: This test helps identify specific types of cells.
• Cytogenetics and molecular studies: These tests look for changes in chromosomes and mutations in certain genes.

After AML has been diagnosed, additional tests may be done to find out if the cancer has spread to other parts of the body^[5]. A lumbar puncture (spinal tap) may be performed to collect cerebrospinal fluid for testing^[12].

Treatment approaches

As AML is an aggressive cancer that grows quickly, treatment will usually begin a few days after a diagnosis has been confirmed^[13]. Chemotherapy is the main treatment for acute myeloid leukaemia^[14]. Targeted therapy and stem cell transplant may also be used^[14].

Treatment for AML is often divided into phases^[14]:

Induction is the first phase of treatment. It involves intense chemotherapy with the goal of clearing the blood and bone marrow of leukaemia cells and bringing about a complete remission. Targeted therapy may also be used if the cancer cells have certain genetic mutations^[14]. You’ll usually be given a combination of two or more chemotherapy medicines^[13]. The treatment will be carried out in hospital or in a specialist centre, as you’ll need very close medical and nursing supervision^[13].

Consolidation is the second phase of treatment, also called post-remission therapy. The goal is to continue to rid the body of leukaemia cells that remain after induction and maintain complete remission to prevent relapse. Consolidation usually involves chemotherapy or a stem cell transplant^[14]. Although the administration of multiagent induction chemotherapy can achieve complete remission, allogeneic stem cell transplantation is the only established curative therapy^[3].

Maintenance is a third phase that may be used for people who aren’t going to have a transplant and who have intermediate or unfavorable chromosome changes. It involves chemotherapy at a lower strength and for a longer period of time^[14].

If you’re thought to have a high risk of experiencing complications of AML treatment (for example, if you’re over 75 or have another underlying health condition), less intensive chemotherapy treatment may be carried out at a lower dosage^[13]. In these cases, newer treatments such as venetoclax plus azacitidine may be used^[11].

For acute promyelocytic leukaemia, specific medicines are used alongside chemotherapy. All trans retinoic acid (ATRA) changes immature white blood cells into healthy mature cells and can reduce symptoms quickly. Arsenic trioxide may be given if the AML has come back^[13].

Side effects of intensive chemotherapy are common and can include feeling or being sick, bruising or bleeding easily, diarrhea, loss of appetite, sore mouth and mouth ulcers, tiredness, skin rashes, hair loss, and infertility^[13]. Most side effects should resolve once treatment has finished. Tell a member of your care team if side effects become particularly troublesome, as there are medicines that can help you cope better^[13].

Living with acute myeloid leukaemia

Coping with a diagnosis of acute myeloid leukaemia can be overwhelming^[16]. AML develops fairly quickly, which means treatment also starts quite quickly. It can feel like you have no time to adjust or think as everything is happening so fast^[16].

Taking good care of yourself can make you feel stronger and healthier during treatment. Nourishing foods can help your body heal and strengthen your immune system. The ideal diet contains protein (from fish, poultry, eggs, beans, and lean red meat), carbohydrates for energy (especially complex carbohydrates like whole grains and vegetables), and healthy fats (from vegetable oils and avocados)^[19].

Treatment side effects like loss of appetite, nausea, changes in taste, and mouth sores can make eating difficult. If you can’t eat large amounts of food at once, have a few small meals during the day instead of three big ones. If it hurts to eat, drink high-protein, high-calorie shakes or smoothies^[19].

Staying as active as possible will give you more energy and fight fatigue. Ask your doctor how to exercise safely with AML. Start slowly and gradually increase the length and intensity of your workouts once you feel ready^[19]. At first, you might only be able to walk for a few minutes at a time^[21].

Talking to your friends and relatives about your cancer can help and support you. You might find it easier to talk to someone other than your own friends and family. Support services and counselors can provide emotional support^[16]. Online forums and support groups allow you to connect with others affected by cancer and share experiences^[16].

Finishing treatment for AML is a big achievement worth celebrating, although it can take time for your body to recover^[20]. Recovering from AML isn’t the same as recovering from other illnesses. It can take several months to rebuild your fitness^[20]. You will have check-ups with your medical team regularly after treatment, which could be several times a week at first. Eventually the check-ups will be monthly, and later every few months. Follow-up appointments last several years^[20].