Leukaemia

The majority of people have heard of leukaemia and understand that it is a form of cancer affecting the blood. Before we explain what leukaemia is, it is helpful to have some knowledge about where blood is made and what it is made up of.

What is bone marrow?

Bone marrow is a soft spongy material that fills up the cavities of the bones. All of the different types of blood cells are made in the bone marrow. In a healthy individual millions of red and white cells are produced and formed daily in the bone marrow.

What are blood cells?

Everyone’s blood is made up of fluid called plasma and three types of blood cells they are as follows:

• White blood cells – they are essential to fight infection. There are 2 main types of white blood cells produced by the bone marrow they are called, neutrophils, produced from myeloid cells and lymphocytes.
• Red blood cells – carry oxygen around the body, they also give blood its red colour.
• Platelets or thrombocytes – the smallest of the blood cells, they are essential for clotting the blood to prevent bleeding.

What is leukaemia?

Leukaemia is a cancer of the white blood cells, the word leukaemia comes from the Greek and means “white blood”.

As there are various types of bone marrow cells, various types of leukaemia can develop each requiring different treatments. The main types of leukaemia are as follows:

• Acute lymphoblastic leukaemia (ALL) – this is a cancer of immature lymphocyte cells, known as lymphoblasts. This disease is the most common type of leukaemia in young children, usually between the ages of 1 and 7 and is quite rare in adults.
• Acute myeloid leukaemia (AML) – this is a cancer of the immature myeloid cells. This disease occurs mainly in adults but can also affect children.
• Chronic lymphocytic leukaemia (CLL) – this is a cancer of the lymphocyte cells. This disease is the most common type of leukaemia affecting adults, and is very rare in children.
• Chronic myeloid leukaemia (CML) – this is a cancer of the neutrophils cells. This type of leukaemia is rare in children and commonly affects male adults more than females.

Acute means the leukaemia comes on suddenly and can progress quickly if not treated. Chronic means the leukaemia is slow to develop and is also slow to progress, even if it isn’t treated.

What causes leukaemia?

Normally, blood cells are produced in a controlled way, which keeps us healthy. Leukaemia develops when the bone marrow starts to produce large numbers of abnormal blood cells. Cells are abnormal when they do not mature as they should. This process disrupts the production of normal blood cells, which means the remaining cells cannot do the jobs they are supposed to do. This is when the patient will begin to experience symptoms of leukaemia, such as anaemia and bruising (due to a lack of red blood cells).

What are the risk factors for getting leukaemia?

There are no known factors, which increase the risk of developing leukaemia. The patient will normally be told from their doctor that the reasons why they developed leukaemia are unknown. However, there are some factors that are thought to increase the risk of developing certain leukaemia’s, these are as follows :-

• In rare cases leukaemia may follow after exposure to chemicals and other solvents used in industry. In recent years there has been an increase in people living near nuclear power plants developing leukaemia, but any link has not been proved.
• People with certain genetic disorders, such as Downs Syndrome are at a higher risk of developing leukaemia, though it’s not understood why this is.
• As with most cancers and diseases smoking, will increase your risk of developing leukaemia. It has been estimated a quarter of all leukaemia cases may be caused by smoking.

What are the signs and symptoms of leukaemia?

The following are symptoms that are common in people with leukaemia, you may only have a few of these symptoms and some may be more obvious than others:

• Unnatural pale complexion.
• Pain in the joints or bones.
• Bruising and bleeding, especially from the nose and gums.
• Fever, chills and other flu like symptoms.
• Night sweats.
• Weakness and fatigue.
• Breathlessness.
• Enlarged lymph glands.
• Repeat infections e.g. sore throats.
• Weight loss.
• Enlarged liver, and spleen, which may cause abdominal discomfort
• Loss of appetite.

Generally, people with leukaemia become weak and tired and appear pale. This is usually because they are anaemic due to a deficiency of red blood cells. Some people will have no symptoms and the disease is picked up during a routine blood test. These symptoms are also common to other illnesses, however, if you have any of these symptoms you should consult your doctor for advice.

How is leukaemia diagnosed?

If you visit your doctor he/she will usually carry out a physical examination to check for any swelling of the liver, spleen or lymph nodes. A blood test will then be required, which will clearly indicate if any leukaemia cells are present. A blood test will determine if the patient has leukaemia, but might not show what type of leukaemia it is. To make an exact diagnosis a bone marrow biopsy is required. A bone marrow biopsy involves a small amount of bone marrow being removed with a needle and syringe, usually from the hip or breast area, for analysis under a microscope. The process is quite straightforward and is carried out under a local anaesthetic.

What treatments are available for leukaemia?

The aim of treatment is to remove the abnormal cells from the bone marrow and the blood. When this happens the patient is said to be in remission (symptom free and no evidence of malignant cells). Once a person with leukaemia has gone 5 years without any treatment or any repercussions of the disease, they are said to be cured. Luckily the majority of children with leukaemia will make a full recovery.

Actual treatment can be very complex but also very effective. The exact treatment will depend on the needs of each patient and the type of leukaemia diagnosed, age and general health will also be taken into consideration.

If the patient has few symptoms and the leukaemia is very slowly progressing, they may not require any treatment. They will however, be monitored carefully and will need to have regular check-ups so treatment can begin if the disease becomes active.

Leukaemia is usually always treated with chemotherapy, as it has proved very effective. The drugs kill the leukaemia cells but also damage the normal cells, this is why the patient can become very ill (vomiting and diarrhoea) as a direct result of the treatment. It is when the treatment has finished that healthy cells begin to grow again. Further treatment will need to be given to prevent the leukaemia from returning, the exact time when the treatment is repeated will depend on the individual.

Radiotherapy may also be given to leukaemia sufferers, along with chemotherapy to relieve symptoms.

Bone marrow transplants are another treatment that offers sufferers the possibility of a cure when the chemotherapy has failed or the leukaemia returns. You will firstly be given high doses of chemotherapy, occasionally combined with radiotherapy to kill your own bone marrow. You will then be given bone marrow cells from a matching donor, (usually a relative) or even your own bone marrow. The donated bone marrow cells are then inserted directly into the veins via a drip. Once the blood cells are in the bloodstream they will find their way to the bone marrow cavity in the bones and hopefully start producing normal blood cells again.