Acute Myeloid Leukaemia
About the Condition
AML is an uncommon type of cancer. Around 2,600 people are diagnosed with the condition each year in the UK*. AML can develop at any age, but it’s more common in people over the age of 60*.
Acute myeloid leukaemia (AML) is caused by a DNA mutation in the stem cells that produce red blood cells, platelets and infection-fighting white blood cells. This mutation causes the stem cells to produce many more white blood cells than are needed. The white blood cells are also produced when they are still immature, so they do not have the infection-fighting properties of fully developed white blood cells. These immature cells are known as “blast cells”. As the number of immature cells increases, the amount of healthy red blood cells and platelets fall, and it’s this fall that causes many of the symptoms of chronic leukaemia.
It is not known what triggers the genetic mutation in AML, although a number of different factors that can increase the risk of developing the condition have been identified as including:
- Radiation exposure – being exposed to a significant level of radiation can increase your chances of developing AML, although this usually requires exposure at very high levels. For example, rates of AML are higher in people who survived the atomic bomb explosions in Japan in 1945. Most people in the UK are very unlikely to be exposed to levels of radiation high enough to cause AML, except for some people who have had radiotherapy as part of their treatment for a previous cancer (see below).
- Benzene and smoking – exposure to the chemical benzene is a known risk factor for AML in adults. This chemical is found in petrol, and is also used in the rubber industry, although there are strict controls to protect people from prolonged exposure. Benzene is also found in cigarette smoke, which could explain why people who smoke have an increased risk of developing AML.
- Previous cancer treatment – treatment with radiotherapy and certain chemotherapy medications for an earlier, unrelated cancer can increase your risk of developing AML many years later. When leukaemia develops because of previous cancer treatment, it is called secondary leukaemia or treatment-related leukaemia.
- Blood disorders – people with certain blood disorders, such as myelodysplasia, myelofibrosis or polycythaemia vera (PCV), have an increased risk of developing AML.
- Genetic disorders – people with certain genetic disorders, including Down’s syndrome and Fanconi’s anaemia, have an increased risk of developing leukaemia.
The symptoms of acute myeloid leukaemia (AML) usually develop over a few weeks, becoming more severe as the number of immature white blood cells (blast cells) in your blood increases. Symptoms of AML can include:
- pale skin
- a high temperature (fever)
- excessive sweating
- weight loss
- frequent infections
- unusual and frequent bleeding, such as bleeding gums or nosebleeds
- easily bruised skin
- flat red or purple spots on the skin (petechiae)
- bone and joint pain
- a feeling of fullness or discomfort in your tummy (abdomen), caused by swelling of the liver or spleen
In rare cases of AML, the affected cells can spread into the central nervous system. This can cause symptoms including:
- Fits (seizures)
- Blurred vision
If any of these symptoms apply to you, or if you have any concerns about similar symptoms, it is essential that you see your doctor at once, as your chances of recovery are much higher if your cancer is diagnosed early.
If you are referred to CCL for diagnosis, your consultant or oncologist will advise you on which tests are relevant for your individual symptoms. There are a variety of different tests used to diagnose AML, which include:
- A blood test, to check for AML indicators such as a high number of abnormal white blood cells, or a very low blood count in the test sample
- A bone marrow biopsy, during which a haematologist will take a small sample of bone marrow to examine under a microscope. This involves inserting a needle into a large bone, usually the hip bone, to extract the marrow, and is done under local anaesthetic
- Cytogenetic testing, which involves identifying the genetic make-up of the cancerous cells. There are specific genetic variations that can occur during leukaemia, and knowing what these variations are can have an important impact on treatment.
- Immunophenotyping, which is a test to help identify the exact type of acute lymphoblastic leukaemia. A sample of blood, bone marrow or another type of fluid is studied.
- A Computerised Tomography (CT) scan, which shows a 3D image of the area being looked at
- An X-ray, which is when low level radiation is used to create an image of the body
- A lumbar puncture, where a needle is used to extract a sample of cerebrospinal fluid (fluid that surrounds and protects your spine) from your back. The fluid is tested to determine whether leukaemia has reached your nervous system, and this test is carried out using local anaesthetic
Acute myeloid leukaemia (AML) is an aggressive condition that develops rapidly, so treatment will usually begin a few days after a diagnosis has been confirmed. At CCL, patients with AML are treated by a team of different specialists, called a Multi-Disciplinary Team, or MDT, from our Haemato-Oncology department, headed by Professor Ray Powles, CBE. This team works together to create a treatment plan to suit the individual needs of the patient.
Treatment for AML is often carried out in two stages:
- Induction – the aim of this initial stage of treatment is to kill as many leukaemia cells in the bone marrow and blood as possible, restore the blood to proper working order and treat any symptoms you may have.
- Consolidation – this stage aims to prevent the cancer returning (relapsing), by killing any remaining leukaemia cells that may be present in the body.
The induction stage of treatment is not always successful and sometimes needs to be repeated before consolidation can begin. The initial treatment for AML will largely depend on whether the patient is healthy enough to have intensive chemotherapy, or whether treatment at a lower dosage is recommended. Induction treatment includes:
- Intensive chemotherapy, which involves using a very high dose of chemical agents which are toxic to cancer cells, destroying them and preventing them from spreading to different areas. This can be given by injection or in tablet form.
- Standard chemotherapy, if the patient is too ill for the higher doses of chemical agents.
- All Trans-Retinoic Acid (ATRA), which is delivered in capsules in addition to chemotherapy, and works by changing the immature white blood cells (blast cells) into mature healthy cells, and can reduce symptoms very quickly.
If induction is successful, the next stage of treatment will be consolidation.
This often involves receiving regular injections of chemotherapy medication that are usually given on an outpatient basis, which means that the patient will not have to stay in hospital overnight. The consolidation phase of treatment lasts several months. Other treatments include:
- Radiotherapy, which involves using high doses of controlled radiation to kill cancerous cells. There are two main reasons why radiotherapy is usually used to treat AML:
- to prepare the body for a bone marrow or stem cell transplant (see below)
- to treat advanced cases that have spread to the nervous system and/or brain, although this is uncommon
- A bone marrow or stem cell transplant, which is a possible alternative if chemotherapy has been unsuccessful. Before transplantation can take place, the patient will need to have intensive high-dose chemotherapy and radiotherapy to destroy the cells in their bone marrow. The donated stem cells are then given through a tube into a blood vessel, in a similar way to chemotherapy medication.
Cancer doesn’t just leave a physical impact on an individual, it can have a huge emotional effect as well. Cancer and its treatment can be overwhelming, causing a wide variety of emotions, and it is important to remember that there is no right or wrong response. Reactions vary hugely from person to person, and most people find that it becomes easier to cope when they’re given additional support, so that’s what we do.
At CCL we provide support that caters to both the physical and emotional needs of the patient, before, during and after treatment. We offer a wide range of services for patients, as well as their loved ones, designed to make a very difficult time as easy as possible, and to give our patients the best treatment and support possible.
Acute Myeloid Leukaemia Consultants