What is Leukemia?
Leukemia affects certain blood cells, particularly the white cells, or leukocytes, which are part of the body’s defence against infection and disease.
There are several different types of Leukemia, classed mainly according to the way the cancer develops and the variety of white blood cells they affect:
Types of Leukemia
Most acute Leukemia is either:
- Acute lymphoblastic Leukemia (ALL) or
- Acute myeloid Leukemia (AML)
Chronic Leukemia is usually either
- Chronic lymphocytic Leukemia (CLL) or
- Chronic myeloid Leukemia (CML)
There are also several less common types.
In acute Leukemia, immature white blood cells accumulate in the body and can disrupt the function of many tissues and organs. Cells in chronic Leukemia are slightly abnormal and don’t function as well as they should.
Often there are no symptoms at first and Leukemia may be a chance finding on a blood test. When symptoms do appear, they may be vague and non-specific, similar to a flu-like illness.
Symptoms of Leukenia may include:
- Generalised weakness and fatigue
- Anaemia – patient is unusually pale, weak and tired.
- Frequent infections, fevers, chills or flu-like symptoms
- Weight loss
- Excessive or easy bruising or bleeding
- Pain in the bones and joints
- Enlarged lymph nodes, liver and/or spleen tender to the touch
- Abdominal discomfort
- Night sweats
- In men, swollen testicles
- Headaches, seizures and vomiting, when the spinal column is affected
Different types of Leukemia develop in different ways. Acute Leukemias progress rapidly, whereas in chronic Leukemia, the symptoms take longer to develop and the decline is far less swift.
The causes of Leukemia have not yet been established.
Leukemia is the most common form of childhood cancer, but is 10 times more common in adults.
The incidence of acute and chronic Leukemia is about equal. Slightly more men than women develop acute Leukemia, and slightly more men than women develop Chronic myeloid Leukemia (CML).
The risk of developing acute Leukemia is increased by:
- Radiation exposure
- Previous cancer and treatment for cancer
- Blood disorders that damage the bone marrow
- Chemical (benzene) exposure increases the risk of Acute myeloid Leukemia (AML)
The risk of developing Chronic myeloid Leukemia (CML) is increased by:
- Radiation exposure
- Chemical (benzene) exposure
The risk of developing Chronic lymphocytic Leukemia (CLL) is increased by:
- Gender (men are more likely to be affected)
- Having a member of the family affected by Chronic lymphocytic Leukemia (CLL)
- The first thing a doctor will do to investigate suspicions of Leukemia is carry out a physical examination, feeling the lymph nodes in the neck, under the arms and in the groin. It can be slightly uncomfortable, but not painful.
- Blood tests will also give an invaluable clue as to both the presence and type of disease. The numbers of various types of cell are physically counted to make sure there are the right number.
- Another key test is a CT scan, which can look for swellings in the lymph nodes, liver, lungs and spleen.
- A sample of bone marrow, normally from the hip, may be taken with a needle. Sometimes a sample of bone is taken for analysis.
- If this confirms the presence of Leukemia cells, a lumbar puncture – which involves inserting a needle through the back into the lower spine – takes more fluid for analysis.
These tests will help doctors work out how aggressive the cancer is, and how far it has already spread.
Not everyone diagnosed with Leukemia will need treatment immediately, and some patients never require treatment (CLL can progress very slowly in some older people). However, for those who do, the earlier it begins the more effective it is.
This may require the patient to stay in the hospital for the duration of treatment.
Treatment for Acute Leukemia can include:
- Intensive treatments (including bone marrow or stem cell implant)
- Growth factors (substances that stimulate the bone marrow to make blood cells)
Bone marrow transplants tend to be carried out if chemotherapy treatment fails and more powerful drugs have to be used. The bone marrow is found at the centre of the body’s larger bones, such as in the spine and upper leg, producing blood cells and helping the body fight infection.
If high-dose chemotherapy is to be used, this may permanently damage the bone marrow, so it has to be replaced afterwards. The patient can be given drugs to stimulate the production of cells vital to rebuilding the bone marrow, which are then collected and replaced after the treatment. Otherwise, a donor may have to be found whose bone marrow is an exact match for the patient (a close relative may be able to provide a match, but this is far from certain).
Treatment for Chronic Leukemia
Treatment for chronic Leukemia can also include biological therapy, such as interferon alpha. Sometimes, drugs are injected through a tube directly into the spinal column or brain to reach the cells there.
Leukemia Survival Rate and Prognosis
Prognosis and survival from Leukemia varies enormously, and depends on factors such as the type of Leukemia you have, how advanced it was when first diagnosed, how well it responds to chemotherapy treatment, and how generally fit you are. Each person should discuss this individually with the team in charge of their care.