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acute lymphoblastic leukaemia Alternative Names
acute lymphoblastic leukaemia, lymphosarcoma leukaemia
Definition
Acute lymphocytic leukaemia (ALL) is cancer of the lymph cells, a type of white blood cell. While ALL is known as the childhood form of leukaemia, 20% of the people who develop the disease are adults.
What is going on in the body?
Lymph cells are a type of white blood cell made in the bone marrow, spleen, and other lymph system tissues. When the body has an infection, the number of lymph cells rises sharply. Two major types of lymph cells are B cells and T cells. They play a role in fighting off infection by making antibodies.
When a person has ALL, the lymph cells do not mature enough to do their job. The cells become malignant and their growth is unchecked. The abnormal cells build up in the bone marrow, blood, and all the tissues in the body.
The word leukaemia means white blood. As abnormal cells crowd out normal blood cells, leukaemia can cause many problems, such as: - anaemia, or a low red blood cell count
- a need for red blood cell transfusions
- bleeding problems due to poorly working clotting cells, called platelets
- loss of normal white blood cell function
Other white blood cells help in immune monitoring and healing. ALL can compromise or even stop all of these functions. The build-up of abnormal lymph cells can enlarge or infiltrate any organ in the body, including lymph nodes and brain.
ALL can occur at any age and in either gender. This disease can strike in a very short period of time.
What are the signs and symptoms of the disease?
ALL can cause symptoms in any part of the body, such as: - blood clotting problems, including nose bleeds, bleeding gums, intestinal bleeding, easy bruising, or tiny red splotches in the skin called petechiae
- general weakness
- fatigue
- weight loss
- loss of appetite
- shortness of breath at rest or with activity
- palpitations or fast heart rate
- hypersensitivity to cold
- nausea and/or constipation
- headaches, light headedness, or dizziness
- unexplained fevers or night sweats
- swollen lymph nodes
People often get infections due to the break down of the immune system. Signs of this are: - skin boils
- thrush, a yeast infection in the mouth
- pneumonia
- sinus infection
- kidney infection
- infectious diarrhoea
- unusual parasite infections
Such problems can be quite mild at first. They almost always worsen over a span of several days to several weeks.
What are the causes and risks of the disease?
ALL is thought to have many causes, including: - exposure to radiation
- exposure to toxins
- viruses that affect the immune system
- gene or chromosome abnormalities that are passed on from parent to child
- a poorly working immune system
It is not clear if a leukaemia virus might spread ALL. It is an uncommon cancer and any risk of it spreading from one person to another is very low.
It is known that people: - who have AIDS are at higher risk for lymphatic cancers, including ALL.
- who have Down's syndrome may be at higher risk for ALL.
- who have been treated for other cancers can get ALL. This is called a secondary leukaemia.
What can be done to prevent the disease?
Right now, ALL cannot be prevented. People can avoid exposure to substances that are considered toxic, such as: - benzene
- toluenes
- arsenic compounds
- the antibiotic chloramphenicol
Radiation from highly radioactive compounds is clearly dangerous. This does not involve household appliances. A person who has had chemotherapy or radiation is at risk for ALL. He or she should be monitored for life.
Occasionally, family clusters of acute leukaemias occur. Genetic screening may make it possible to prevent this disease, though this would only help a small percentage of people. Whether or not nutrition and generally avoiding infections are of benefit in preventing ALL is actively being researched.
How is the disease diagnosed?
ALL is not hard to diagnose. Samples of blood and bone marrow cells taken during a biopsy are examined for a build-up of immature cells, called lymphoblasts, and abnormal lymph cells. Results are generally available in 1 or 2 days.
Afterward, other tests are done to evaluate the extent of the disease, such as: - blood tests
- tests to check the functions of organs like the kidneys, liver, heart, and lungs
- scans of the brain and body to check for any tumour masses, bone weakness, or bleeding sites
- spinal tap
Sometimes ALL is described more specifically by the type of cells affected. Subcategories include: - B or T cell
- non-B or non-T cell
- L1, L2, or L3 types
While these subcategories help describe the expected progress of the disease, treatment is usually similar.
What are the long-term effects of the disease?
Some people live an entirely normal, healthy life after this disease has been treated and cured. However, ALL can be lethal even when treated. People who survive often have many chronic health problems. Any organ, including the brain, can be damaged before treatment starts. The treatments can have serious permanent side effects, too.
What are the risks to others?
It is not clear whether ALL can be spread to others. It is possible, though, that the unusual or aggressive infections people with ALL have, might spread to others. This is more likely to happen when AIDS or another disorder weakens a person's immune system.
What are the treatments for the disease?
Treatment for ALL may include: - surgery to implant a tube into a major vein to deliver medication or gain quick access to the bloodstream.
- bone marrow transplant from a matched donor.
- chemotherapy for months or occasionally up to a year. Chemotherapy may be given by intravenous (IV) or mouth, or inserted into the spinal fluid if leukaemia has spread to the brain and nervous system.
- radiation of the brain and spine, which is done frequently to treat even tiny, hidden leukaemia cells.
- intravenous feeding for people who cannot eat, swallow, or digest food.
People are treated in a hospital at first, then later as outpatients. Treatment can go on for several months to a couple of years depending on the case.
The goal of treatment is a cure, or at least remission. Remission is considered to be the disappearance of symptoms and signs of ALL. If the cancer returns, a bone marrow transplant or salvage therapy may be done. Salvage therapy is chemotherapy used to try to get a second remission or to extend life.
What are the side effects of the treatments?
Side effects of treatments can include some of the same signs and symptoms as the leukaemia, such as: - weakness and fatigue
- weight loss
- bleeding problems that may require transfusions
- common or unusual infections
- irritation of the gastrointestinal tract
- mouth sores
- diarrhoea or poor food absorption
- numbness or burning pain in the extremities
- nausea and vomiting
- allergic reactions to medications
When treatment involves the brain and nervous system, people temporarily may: Impaired memory, math skills, or motor skills, and sterility can be permanent with this type of treatment.
What happens after treatment for the disease?
People often need long-term care for complications from leukaemia or its treatments. Children may have more neurological or psychological problems. Developing bones can be affected, too. Adults have fewer of these complications, but have a lower rate of remission and cure.
How is the disease monitored?
People who have been treated for ALL are often followed and checked with tests for recurrences for several years. ALL is monitored by: - physical examinations
- blood tests
- evaluation of bone marrow and biopsies
Sometimes spinal taps are done. The fluid is tested for signs of cancer. Genetic testing of the bone marrow may be done, too. It can find traces of residual leukaemia before other tests do.
Author: Thomas Fisher, MD
Reviewer: HealthAnswers Australia Medical Review Panel
Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia
Last Updated: 1/10/2001
Contributors
Potential conflict of interest information for reviewers available on request |
