Bookmark and Share

Monday, April 5, 2010

Acute Lymphoblastic Leukaemia in Children

This information is about acute lymphoblastic leukaemia in children. It is helpful to read general information on children's cancer, which contains more information about cancers in children, their diagnosis and treatment and the support services available.
* Leukaemia
* ALL
* Causes of ALL
* Signs and symptoms
* How it is diagnosed
* Treatment
* Side effects of treatment
* Clinical trials
* Follow-up
* Your feelings
* References
Leukaemia
One third of all childhood cancers are leukaemia, with approximately 400 new cases occurring each year in the UK. Approximately three quarters (75%) of these are acute lymphoblastic leukaemia. ALL can affect children at any age but is more common between the ages of 1 and 4. ALL is more common in boys than girls.
ALL
Leukaemia is a cancer of the white blood cells. All blood cells are produced in the bone marrow. Bone marrow is the spongy substance at the core of some of the bones in the body. Bone marrow contains:
* red blood cells that carry oxygen around the body
* white blood cells that help fight infection
* platelets that help the blood to clot and control bleeding.
There are two different types of white cell: lymphocytes or myeloid cells. These white blood cells work together to fight infection. Normally white blood cells repair and reproduce themselves in an orderly and controlled way. In leukaemia, however, the process gets out of control and the cells continue to divide, but do not mature.
These immature dividing cells fill up the bone marrow and stop it from making healthy blood cells. As the leukaemic cells are not mature, they cannot work properly. This leads to an increased risk of infection. Because the bone marrow cannot make enough healthy red blood cells and platelets, symptoms such as anaemia and bruising can occur.
There are four main types of leukaemia: acute lymphoblastic (ALL), acute myeloid (AML), chronic lymphocytic (CLL) and chronic myeloid (CML). Chronic leukaemias usually affect adults and are extremely rare in children and young people. Each type of leukaemia has its own characteristics and treatment. Acute lymphoblastic leukaemia is a cancer of immature lymphocytes, called lymphoblasts or blast cells.
There are two different types of lymphocytes: T-cells and B-cells. Often the leukaemia occurs at a very early stage in the immature lymphocytes, before they have developed as far as becoming either T-cells or B-cells. However, if the cells have developed this far before becoming leukaemic, the type of leukaemia may be known as T-cell or B-cell leukaemia.
Causes of ALL
The exact cause of ALL is unknown. Research is going on all the time into possible causes of this disease. Children with certain genetic disorders, such as Down's syndrome, are known to have a higher risk of developing leukaemia. Brothers and sisters of a child with ALL have a slightly increased risk of developing ALL themselves, although this risk is still small.
In recent years there has been publicity about leukaemia occurring more often in children living close to nuclear power plants or high-voltage power lines. Research is still under way to see if there is any definite link between these factors but as yet there is no evidence of this. ALL, like other types of cancer, is not infectious and cannot be passed on to other people.
Signs and symptoms
As the leukaemia cells multiply in the bone marrow, the production of normal blood cells is reduced. Children may therefore become tired and lethargic due to anaemia, which is caused by a lack of red blood cells. They may develop bruises, and bleeding may take longer to stop due to low numbers of platelets. Sometimes children may suffer from infections because of low numbers of normal white blood cells.
A child is likely to feel generally unwell and may complain of aches and pains in the limbs, or may have swollen lymph glands. At first the symptoms are just like those of a viral infection, but when they continue for more than a week or two the diagnosis usually becomes clear.
How it is diagnosed
A blood test usually shows low numbers of normal white blood cells and the presence of the abnormal leukaemic cells. A sample of bone marrow is needed to confirm the diagnosis. A lumbar puncture is done to see if the spinal fluid contains any leukaemia cells. A chest x-ray is also done, which will show if there are any enlarged glands in the chest. Other tests may be necessary, depending on the child's symptoms.
These tests will help to identify the precise type of leukaemia involved.
Treatment
The aim of treatment for ALL is to destroy the leukaemia cells and allow the bone marrow to work normally again. Chemotherapy is the main treatment for ALL. Usually a combination of chemotherapy drugs are given according to a treatment plan (often called a protocol or regimen). The treatment is given in several phases, or 'blocks', which are outlined below.
Induction This phase involves intensive treatment aimed at destroying as many leukaemia cells as possible. The induction phase lasts for 4-6 weeks. A bone-marrow test is taken at the end of induction treatment to check if the child is in remission. Remission is where there is no evidence of leukaemia.
Consolidation and central nervous system (CNS) treatment The next phase of treatment is aimed at maintaining the remission and also at preventing the spread of leukaemia cells into the brain and spinal cord (the central nervous system). CNS treatment involves injecting a drug, usually methotrexate, directly into the spinal fluid (intrathecally) during a lumbar puncture. Occasionally radiotherapy to the brain is also necessary.
Further doses of chemotherapy treatment (somtimes called 'intensification blocks') are given in order to kill off any remaining leukaemia cells. Between 2 and 4 blocks of treatment may be needed, depending on your child's particular treatment plan.
Maintenance treatment This phase of treatment lasts for up to 2 years for girls and up to 3 years for boys, from diagnosis. It involves daily tablets and monthly injections of chemotherapy.
Children will be able to take part in their normal daily activities as soon as they feel able to. Some children return to school before maintenance treatment.
Bone-marrow transplantation Bone-marrow transplantation is only used for children with ALL that is likely to come back following standard chemotherapy, or for children whose leukaemia has come back (recurred) following standard treatment.
Testicular radiotherapy In some situations it may be necessary for boys to have radiotherapy to their testicles. This is because leukaemia cells can survive in the testicles despite chemotherapy.
Side effects of treatment
Many cancer treatments will cause side effects. This is because while the treatments are killing the cancer cells they can also damage some normal cells. Some of the main side effects are:
* hair loss
* reduction in the number of blood cells produced by the bone marrow, which can cause anemia, an increased risk of bruising, bleeding and infection
* loss of appetite and weight
* nausea (feeling sick) and vomiting
Most side effects are temporary and there are ways of reducing them and supporting your child through them. Your child's doctor or nurse will talk to you about any possible side effects.
Late side effects
A small number of children may develop late side effects, sometimes many years later. These include possible problems with puberty and fertility, a change in the way the heart works and a small increase in the risk of developing another cancer in later life. Your child's doctor or nurse will explain about any possible late side effects.
Clinical trials
Many children have their treatment as part of a clinical research trial. Trials aim to improve our understanding of the best way to treat an illness (usually by comparing the standard treatment with a new or modified version of the standard treatment). Specialist doctors carry out trials for ALL. Your child's medical team will talk to you about taking part in a clinical trial (if appropriate) and will answer any questions you may have. Written information is often provided to help explain things. Taking part in a research trial is completely voluntary and you'll be given plenty of time to decide if it is right for your child. At present the main trial for ALL is called 'UKALL 2003'.
Most children with ALL are cured. If the leukaemia comes back, it normally does so within the first three years after stopping treatment. Further treatment can then be given. Long-term side effects are uncommon and most children with ALL grow and develop normally.
If you have specific concerns about your child's condition and treatment, it is best to discuss them with your child's doctor, who knows the situation in detail.
Your feelings
As a parent, the fact that your child has cancer is one of the worst situations to face. You may have many different emotions, such as fear, guilt, sadness, anger and uncertainty. These are all normal reactions and are part of the process that many parents go through at such a difficult time. There is not enough space here to address all of the feelings you may have. However, general information on children's cancer talks about the emotional impact of caring for a child with cancer and suggests sources of help and support.

No comments: