About acute myeloid leukemia (AML)
AML is characterised by an overproduction of immature white blood cells, called myeloblasts or leukaemic blasts. These cells crowd the bone marrow, preventing it from making normal blood cells. They can also spill out into the bloodstream and circulate around the body. Due to their immaturity they are unable to function properly to prevent or fight infection. Inadequate numbers of red cells and platelets being made by the marrow can cause anaemia, easy bleeding, and/or bruising.
Acute myeloid leukaemia is sometimes called acute myelocytic, myelogenous or granulocytic leukaemia.
Which type of AML do I have?
AML is classified into eight different subtypes based on the appearance of the leukaemic cells under the microscope. Each subtype provides information on the type of blood cell involved and the point at which it stopped maturing properly in the bone marrow. This is known as the French-American-British (FAB) classification system.
The current World Health Organisation’s classification system for AML uses additional information obtained from more specialised laboratory techniques, like genetic studies, to classify AML more precisely. This information also provides more reliable information regarding the likely course (prognosis), of a particular subtype of AML, and the best way to treat it.
Some subtypes of AML are associated with specific symptoms, for example, acute promyelocytic leukaemia (APML or M3) is associated with bleeding and abnormalities in blood clotting.
What is the prognosis of AML?
The most important factor in predicting prognosis in AML is the genetic make-up of the leukaemic cells. Certain cytogenetic changes are associated with a more favourable prognosis than others. This means that they are more likely to respond well to treatment, and may even be cured.
Favourable cytogenetic changes include: a translocation between chromosome 8 and 21 t(8;21), inversion of chromosome 16; inv(16) and a translocation between chromosome 15 and 17; t(15;17). This final change is found in AML subtype acute promyelocytic leukaemia (APML or M3). APML is treated differently to other types of AML, and usually has the best overall prognosis.
Other cytogenetic changes are associated with an average or intermediate prognosis, while others are associated with a poor, or unfavourable prognosis. It is important to note that in most cases of AML, neither ‘good’ nor ‘bad-risk’ cytogenetic changes are found. People with ‘normal’ cytogenetics are also regarded as having an average prognosis.
How common is AML?
Each year in Australia around 900 people are diagnosed with AML. Overall AML is rare disease, accounting for 0.8% of all cancers diagnosed, at a rate of 3.7 per 100,000 of population.
Who gets it?
AML can occur at any age but is more common in adults over the age of 60. Around 50 children (0-14 years) are diagnosed with AML in Australia each year. It occurs more frequently in males than females.
Causes of acute myeloid leukemia (AML)
In most cases the causes of AML remain largely unknown but it is thought to result from damage to one or more of the genes that normally control blood cell development. Research is going on all the time into possible causes of this damage and certain factors have been identified that may put some people at an increased risk. These include exposure to:
- very high doses of radiation, either accidentally (nuclear accident) or therapeutically (to treat other cancers)
- industrial chemicals like benzene, over a long period of time
- certain types of chemotherapy that treat other cancers
- some congenital disorders are associated with the development of AML, like Down’s syndrome, Bloom syndrome and Fanconi’s anaemia. In these cases the AML tends to develop in childhood or adolescence. In very rare cases, AML develops because an abnormal gene is passed down from one generation to the next.
- some people with pre-existing blood disorders including certain myelodysplastic syndromes (MDS) and myelofibrosis, aplastic anaemia and paroxysmal nocturnal haemoglobinuria have a higher than average risk of developing AML
- cancer-causing substances in tobacco smoke.
Symptoms of acute myeloid leukemia (AML)
The main symptoms of AML are caused by a lack of normal blood cells. Because AML develops quickly people usually report feeling unwell for only a short period of time (days or weeks) before they are diagnosed. Common AML symptoms may include:
- anaemia due to a lack of red cells, causing persistent tiredness, dizziness, paleness, or shortness of breath when physically active
- frequent or repeated infections and slow healing due to a lack of normal white cells, especially neutrophils
- increased or unexplained bleeding or bruising, due to a very low platelet count
- bone pain, swollen lymph nodes (glands), swollen gums, chest pain and abdominal discomfort due to a swollen spleen or liver.
Occasionally people have no symptoms at all and AML is diagnosed during a routine blood test. Some of these symptoms described may also be seen in other illnesses, including viral infections, so it is important to see your doctor so that you can be examined and treated properly.
Diagnosis of acute myeloid leukemia (AML)
AML is diagnosed by examining samples of your blood and bone marrow in a variety of tests.
Full blood count
The first step in the diagnosis is a simple blood test called a full blood count (FBC) or complete blood count (CBC). This involves a sample of blood from a vein in your arm being sent to the laboratory for investigation. Many of the white blood cells may be abnormal leukaemic blast cells and the presence of these blast cells suggests you have AML.
Bone marrow examination
If the results of your blood tests suggest that you might have AML, a bone marrow biopsy may be required to help confirm the diagnosis. A bone marrow biopsy involves taking a sample of bone marrow, usually from the back of the hip bone, and sending it to the laboratory for examination under the microscope. The bone marrow biopsy may be done in the haematologist’s rooms, a clinic or a day procedure centre and it is usually performed under local anaesthesia with sedation given either by tablet or through a small drip in your arm. The sample of bone marrow is examined in the laboratory to determine the number and type of cells present and the amount of haemopoiesis (blood forming) activity taking place there. The diagnosis of AML is confirmed by the presence of an excessive number of blast cells in the bone marrow.
Further testing
Once an AML diagnosis is made, blood and bone marrow cells are examined further using special laboratory tests. These include immunophenotyping and cytogenetic tests. These tests provide more information about the exact type of disease you have, the likely course of your disease and the best way to treat it.
Other tests
Tests may be conducted to provide information on your general health and how your vital organs are functioning. These include a combination of further blood tests and imaging tests (x-rays, scans and ECG). These results will provide a baseline of your disease and general health which will be compared with later results to assess how well you are progressing and responding to treatment.
Treatment of acute myeloid leukemia (AML)
Because it progresses quickly, treatment for acute myeloid leukaemia needs to begin soon after it is diagnosed. Although there is a degree of urgency, all necessary information from the tests and scans that were conducted is vital to ensure the doctors offer the appropriate treatment to the individual. The type of treatment used will depend on a number of factors including the sub-type of AML you have, the genetic make-up of the leukaemic cells, your age and general health.
Chemotherapy
Chemotherapy is the main form of treatment for AML. Initially the aim of treatment is to destroy leukaemic cells and induce a remission. This means that there is no evidence of leukaemic cells in the blood and bone marrow and that normal blood cell production and normal blood counts are restored. Once a remission has been achieved, more chemotherapy is given to try to prevent the leukaemia from returning (relapsing). This is called post-remission or consolidation therapy.
Chemotherapy is usually given as a combination of drugs, usually given over a period of a week or so. Further courses of chemotherapy are given but are spaced out by three or four weeks. In most cases the drugs are given as infusions through a special line called a central venous catheter, which will be inserted before you start treatment.
Post-remission treatment
Once remission has been achieved, some form of post-remission therapy is given to reduce the risk of the leukaemia coming back. The type of post-remission treatment used will depend on several factors including the type of disease involved, how well it responded to induction therapy, your age and your general health. In some cases, where there is a high risk that the leukaemia will relapse, patients may be offered even more intensive therapy followed by a stem cell transplant.
The treatment of acute promyelocytic leukaemia (APML or M3) differs from the treatment of other types of acute leukaemia. For information on APML and how it is treated explore our section on APML.
Although a high proportion of patients with AML will achieve remission a proportion will relapse. Relapsed AML tends to be more resistant to treatment. If a patient has not undergone an allogeneic transplant this treatment option will be considered. For patients who have undergone a transplant, it may be possible to use immune system cells from the original donor to treat the disease. If it is not feasible to attempt aggressive therapy, reasonable control of the disease for a short period may be obtained with low dose chemotherapy.
Side effects of AML treatment
All treatments can cause side effects. However, the type and severity will vary between individuals, depending on the type of treatment used and how an individual responds to it. In general, more intensive treatment is associated with more severe side effects. It is important to report any symptoms you are having to your doctor or nurse. In most cases they can be treated and are reversible.
When to contact your doctor or hospital
As a general rule, while you are having treatment you will need to contact your doctor or hospital immediately if you experience any of the following:
- a temperature of 38oC or higher (even if it returns to normal) and/or an episode of uncontrolled shivering (a rigor)
- bleeding or bruising, for example blood in your urine, faeces, or sputum; bleeding gums, or a persistent nose bleed
- nausea or vomiting that prevents you from eating or drinking or taking your normal medications
- severe diarrhoea, stomach cramps or constipation
- coughing or shortness of breath
- a new rash, reddening of the skin, itching
- a persistent headache
- a new pain or soreness anywhere
- if you cut or otherwise injure yourself
- if you notice pain, swelling, redness or pus anywhere on your body.
What are the side effects of AML treatment?
Effects on the bone marrow
Chemotherapy affects the bone marrow’s ability to produce adequate numbers of blood cells. As a result, your blood count (the number of white cells, platelets and red cells circulating in your blood) will generally fall within a week of treatment. The length of time it takes for your bone marrow and blood counts to recover mainly depends on the type of chemotherapy given.
When your platelet count is very low (thrombocytopenic) you can bruise and bleed more easily. In many cases a transfusion of platelets is given to reduce the risk of bleeding until the platelet count recovers.
If your red blood cell count and haemoglobin levels drop you will probably become anaemic. When you are anaemic you feel more tired and lethargic than usual. If your haemoglobin level is very low, your doctor may prescribe a blood transfusion.
Risk of infection
The point at which your white blood cell count is at its lowest is called the nadir. This is usually expected 10-14 days after having your chemotherapy. During this time you will be at a higher risk of developing an infection. At this stage you will also be neutropenic, which means that your neutrophil count is low.
Neutrophils are important white blood cells that help us to fight infection. While your white blood cell count is low you should take sensible precautions to help prevent infection. These include avoiding crowds, avoiding close contact with people with infections who are contagious (for example colds, flu, chicken pox) and only eating food that has been properly prepared and cooked. If you do develop an infection you may experience a fever, which may or may not be accompanied by an episode of shivering where you shake uncontrollably. Infections while you are neutropenic can be quite serious and need to be treated with antibiotics as soon as possible. Sometimes your doctor may decide to use a drug to help the recovery of your neutrophil count. This drug works by stimulating the bone marrow to increase the production of neutrophils and is usually given as an injection under the skin (subcutaneous).
Nausea and vomiting
Nausea and vomiting are often associated with chemotherapy and some forms of radiotherapy. These days however, thanks to significant improvements in anti-sickness (anti-emetic) drugs, nausea and vomiting are generally very well controlled. You will be given anti-sickness drugs before and for a few days after your chemotherapy treatment. Be sure to tell the nurses and doctors if the anti-emetics are not working for you and you still feel sick. Some people find that eating smaller meals more frequently during the day, rather than a few large meals, helps to reduce nausea and vomiting. Many find that eating cool or cold food is more palatable, for example jelly or custard. Drinking ginger ale or soda water and eating dry toast may also help if you are feeling sick.
Changes in taste and smell
Both chemotherapy and radiation therapy can cause changes to your sense of taste and smell. This is usually temporary but in some cases it lasts up to several months.
Mucositis
Mucositis, or inflammation of the lining of the mouth, throat or gut is a common and uncomfortable side effect of chemotherapy and some forms of radiotherapy. It usually starts about a week after the treatment has finished and goes away once your blood count recovers, usually a couple of weeks later. During this time your mouth and throat could get quite sore. Soluble pain medication and other topical drugs (ones which can be applied to the sore area) can help. If the pain becomes more severe, stronger pain killers might be needed. It is important to keep your mouth as clean as possible while you are having treatment to help prevent infection. Avoid commercial mouthwashes, as these are often too strong or may contain alcohol, which will hurt your mouth.
Bowel changes
Chemotherapy can cause some damage to the lining of your bowel wall. This can lead to cramping, wind, abdominal swelling and diarrhoea. Be sure to tell the nurses and doctors if you experience any of these symptoms. If you are constipated or if you are feeling any discomfort or tenderness around your anus when you are trying to move your bowels, you may need a gentle laxative to help soften your bowel motions.
Hair loss
Hair loss is unfortunately a very common side effect of chemotherapy and some forms of radiotherapy. It is, however, usually only temporary. The hair can start to fall out within a couple of weeks of treatment and tends to grow back three to six months later. Avoiding using heat or chemicals and only using a soft hairbrush and a mild baby shampoo can help reduce the itchiness and scalp tenderness which can occur while you are losing your hair. You need to avoid direct sunlight on your exposed head (wear a hat) because chemotherapy and radiotherapy makes your skin even more vulnerable to the damaging effects of the sun (like sunburn and skin cancers). Remember that without your hair your head can get quite cold so a beanie might be useful. Hair can also be lost from your eyebrows, eyelashes, arms and legs.
Fatigue
Most people experience some degree of tiredness in the days and weeks following chemotherapy and radiotherapy. Getting plenty of rest and doing a little light exercise each day may help to make you feel better during this time. It is important to listen to your body and rest when you are tired.
Fertility
Some types of chemotherapy and radiotherapy may cause a temporary or permanent reduction in your fertility. If possible, before you commence treatment you should discuss any questions or concerns you might have regarding your future fertility with your doctor. In women, some types of chemotherapy and radiotherapy can cause varying degrees of damage to the normal functioning of the ovaries.
In men, sperm production can be impaired for a while but the production of new sperm may become normal again in the future. There are some options for preserving your fertility, if necessary, while you are having treatment for leukaemia.
Early menopause
Some cancer treatments can affect the normal functioning of the ovaries. This can sometimes lead to infertility and an earlier than expected onset of menopause, even at a young age. The onset of menopause in these circumstances can be sudden and, understandably, very distressing. Hormone changes can lead to many of the classic symptoms of menopause. Some women experience decreased sexual drive, anxiety and even depressive symptoms during this time. It is important that you discuss any changes to your periods with your doctor or nurse.
Body image, sexuality and sexual activity
Hair loss, skin changes and fatigue can all interfere with how you feel about yourself as a man or a woman and as a ‘sexual being’. During treatment you may experience a decrease in libido and it may take some time for things to return to ‘normal’. It’s perfectly reasonable and safe to have sex while you are on treatment or shortly afterwards, but there are some precautions you need to take. It is usually recommended that you or your partner do not become pregnant as some of the treatments given might harm the developing baby. As such, you need to ensure that you or your partner use a suitable form of contraception. Condoms are also necessary in the seven days following a treatment session, to ensure that your partner is not exposed to any residual drugs. Partners are sometimes afraid that sex might in some way harm the patient. This is not likely as long as the partner is free from any infections and the sex is relatively gentle.
Parotitis
Associated with radiotherapy, parotitis is an inflammation of the saliva-producing glands in the mouth, which can occur if these glands are within the treatment field used. These include the parotid or submandibular glands, which are situated at the top of the jaw line, in front of the ears. Parotitis causes dryness of the mouth and jaw pain, which usually settles down within a few days, once the inflammation subsides.
Caring for someone with acute myeloid leukemia (AML)
We have a range of information and resources that may help when you are caring for someone with acute myeloid leukemia (AML).
