Acute Lymphoblastic Leukaemia
About the Condition
Acute lymphoblastic leukaemia, or ALL, occurs when the genetic material of cells in the bone marrow become damaged or changed, producing mutations that affect normal cell growth and division. The abnormal cells then replicate, causing cancer. If undetected, the cancer can spread beyond the bone marrow and move to other parts of the body. All of the blood cells in the body are produced by bone marrow – a spongy material found inside bones. Bone marrow produces specialised cells called stem cells which have the ability to develop into three important types of blood cells:
- red blood cells, which carry oxygen around the body
- white blood cells, which help fight infection
- platelets, which help stop bleeding
Usually the bone marrow produces stem cells which are allowed to fully develop before being released into the blood. But in acute leukaemia, bone marrow starts releasing large numbers of immature white blood cells known as blast cells. As the number of blast cells increases there is a drop in the number of red blood cells and platelet cells. This drop causes the symptoms of anaemia, such as tiredness, and increases the risk of excessive bleeding. Blast cells are less effective than mature white blood cells at fighting bacteria and viruses, making you more vulnerable to infection.
Around 8,600 people are diagnosed with leukaemia each year in the UK*. In 2011, 654 people were diagnosed with acute lymphoblastic leukaemia*. Despite being uncommon overall, acute lymphoblastic leukaemia is the most common type of cancer to affect children. Approximately one in every 2,000 children will develop it*. About 85% of cases occur in children aged under 15, mostly between the ages of two and five years old*.
The cause or causes of acute leukaemia are uncertain, but known risk factors include:
- Exposure to high levels of radiation
- Exposure to benzene, a chemical used in manufacturing that is also found in cigarettes
- Genetic disorders such as Down’s Syndrome
- Being obese
- Having a weakened immune system – due to HIV or AIDS or taking immunosuppressants after an organ transplant
Symptoms of ALL usually begin slowly before rapidly getting severe as the number of blast cells (immature white blood cells) in your blood increases. Most of the symptoms are caused by the lack of healthy blood cells in your blood supply.
Symptoms of ALL include:
- pale skin
- feeling tired and breathless
- having repeated infections over a short space of time
- unusual and frequent bleeding, such as bleeding gums or nose bleeds
- high temperature (fever) of 38C (100.4F) or above
- night sweats
- bone and joint pain
- easily bruised skin
- swollen lymph nodes (glands)
- abdominal pain – caused by a swollen liver or spleen
- unexplained weight loss
- a purple skin rash (purpura)
In some cases of ALL, the affected cells can spread from your bloodstream into your central nervous system. This can cause a series of neurological symptoms (related to the brain and nervous system), including:
- seizures (fits)
- 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’re referred to CCL for diagnosis, your consultant or oncologist will advise you on which tests are relevant to your individual symptoms. There are a number of different tests for ALL, including:
- A blood test, to check for a high number of abnormal white blood cells in the sample, which could indicate the presence of acute leukaemia
- 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 polymerase chain reaction (PCR) test, which can be done on a blood sample. This is an important test to diagnose and monitor the response to treatment.
- If you have been diagnosed with acute leukaemia, further biopsies may be carried out on any enlarged lymph nodes that you have. These will be able to establish how far the leukaemia has spread.
- 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
At CCL, patients with ALL 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 ALL usually begins a few days after diagnosis, and is carried out in the following stages:
- induction – the aim of the initial stage of treatment is to kill the leukaemia cells in your bone marrow, restore the balance of cells in your blood and resolve any symptoms you may have
- consolidation – this stage aims to kill any remaining leukaemia cells in your central nervous system
- maintenance – the final stage involves taking regular doses of chemotherapy tablets to prevent the leukaemia returning