|Daniel Whyte Ivor Burford
|Leukaemia Trust
What is Leukaemia?
Overview
Leukaemia is cancer of the blood. The causes are not yet fully known, and a cure is by no means certain. Despite huge medical advances, leukaemia remains the most devastating disease. "If you are Black or Mixed-Race and diagnosed with LEUKAEMIA Cancer or certain types of blood disorder illness, your chances of finding a bone marrow match is 1 in 100,000+ in comparison to Whites (Caucasians) 1 in 5."
Leukemia is a form of cancer that begins in the blood-forming cells of the bone marrow - the soft, inner part of the bones. Leukemia - which literally means "white blood" in Greek - occurs when there is an excess of abnormal white blood cells in the blood. Known as leukocytes, these cells are so plentiful in some individuals that the blood actually has a whitish tinge.
Under normal circumstances, the blood-forming, or hematopoietic, cells of the bone marrow make leukocytes to defend the body against infectious organisms such as viruses and bacteria. But if some leukocytes are damaged and remain in an immature form, they become poor infection fighters that multiply excessively and do not die off as they should.
The leukemic cells accumulate and lessen the production of oxygen-carrying red blood cells (eythrocytes), blood-clotting cells (platelets), and normal leukocytes. If untreated, the surplus leukemic cells overwhelm the bone marrow, enter the bloodstream, and eventually invade other parts of the body, such as the lymph nodes, spleen, liver, and central nervous system (brain, spinal cord). In this way, the behavior of leukemia is different than that of other cancers, which usually begin in major organs and ultimately spread to the bone marrow.
There are more than a dozen varieties of leukemia, but the following four types are the most common:
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acute lymphocytic leukemia (ALL),
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acute myelogenous leukemia (AML),
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chronic lymphocytic leukemia (CLL), and
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chronic myelogenous leukemia (CML) .
Acute leukemias usually develop suddenly, whereas some chronic varieties may exist for years before they are diagnosed.
Leukemia often is thought to be a childhood disease. In fact, leukemia strikes 10 times as many adults as children. Acute myelogenous leukemia (AML) is the most frequently reported form of leukemia in adults. About 41% of the 30,200 latest cases will have chronic leukemia - an estimated 7,800 chronic lymphocytic leukemia (CLL) cases and 4,500 chronic myelogenous leukemia (CML) cases. In addition, hairy cell leukemia (HCL), a slow-growing lymphocytic cancer, will account for about 604 cases (2% of all leukemias).
Acute myelogenous leukemia (AML) is the most common adult form of leukemia, affecting nearly 5 in every 100,000 men each year. Chronic leukemia, like many other cancers, is a "disease of old age." The average age of individuals with chronic lymphocytic leukemia (CLL) is roughly 70 years, and the average age of chronic myelogenous leukemia (CML) patients is 40 to 50 years. By contrast, acute lymphocytic leukemia (ALL) is largely a pediatric disease, usually appearing in children who are under 10 years of age. In general, leukemia affects more men than women throughout the world, although the male:female ratio is highest in CLL patients in Western countries.
Bone Marrow & Blood Formation
In humans, the bones are not solid, but are made up of two distinct regions. The outer, weight-bearing area is hard, compact, and calcium-based. It surrounds a lattice-work of fibrous bone known as cancellous tissue. The inner region, or marrow - which is one of the largest organs of the body - is located within the bones.
It fills the shafts of the long bones, the trabeculae (spaces within cancellous tissue), and even extends into the bony canals that hold the blood vessels. Read more
Causes
Although researchers have studied the many cellular changes associated with leukemia, no one really knows why such changes occur. It is likely that certain risk factors make individuals more prone to developing leukemia. Many factors - such as age and genetics - are probably beyond our control. Other factors, such as environmental or lifestyle-related variables, may be more correctable.
It is now known that all cancers, including leukemia, begin as a mutation in the genetic material - the DNA (deoxyribonucleic acid) - within certain cells. The external or internal causes of such change probably add up over a lifetime. Leukemia begins when one or more white blood cells experience DNA loss or damage. Read more
Treatment
Leukemia is not a single disease. Instead, the term leukemia refers to a number of related cancers that start in the blood-forming cells of the bone marrow. There are both acute and chronic forms of leukemia, each with many subtypes that vary in their response to treatment. In addition, children with leukemia have special needs that are best met by care in pediatric cancer centers. Such centers have trained medical professionals whose sole purpose is to address the unique concerns of children. Read more
Symthoms
The first indications of leukemia often are nonspecific or vague. They may occur with other cancerous as well as noncancerous disorders. Although signs and symptoms vary for each type of leukemia, there are some general features. Broad symptoms of leukemia may include:
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Fatigue
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Malaise (vague feeling of bodily discomfort)
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Abnormal bleeding
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Excessive bruising
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Weakness
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Reduced exercise tolerance
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Weight loss
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Bone or joint pain
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Infection and fever
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Abdominal pain or "fullness"
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Enlarged spleen, lymph nodes, and liver. Read more
Types of leukaemia
Leukaemia is classified by how quickly it progresses. Acute leukemia is fast-growing and can overrun the body within a few weeks or months. By contrast, chronic leukemia is slow-growing and progressively worsens over years.
Acute versus Chronic Leukaemia
The blood-forming (hematopoietic) cells of acute leukemia remain in an immature state, so they reproduce and accumulate very rapidly. Therefore, acute leukemia needs to be treated immediately, otherwise the disease may be fatal within a few months. Fortunately, some subtypes of acute leukemia respond very well to available therapies and they are curable. Children often develop acute forms of leukemia, which are managed differently from leukemia in adults. Read more
Treatment Options by Type of Leukemia
Acute Myelogenous Leukemia (AML)
Many different chemotherapeutic plans are available for the treatment of AML. Overall, the strategy is to control bone marrow and systemic (whole-body) disease while offering specific treatment for the central nervous system (CNS), if involved. In general, most oncologists rely on combinations of drugs for the initial, induction phase of chemotherapy. Read more
Diagnosis
Once the physician suspects that a patient's blood is abnormal, he or she will want to perform blood and bone marrow tests to rule out leukemia. Additional tissue samples may be needed to confirm the diagnosis or to help plan treatment .
Blood Tests
In cases of questionable leukemia, a number of blood tests are performed. Such tests evaluate the type and quantity of blood cells that are present, the blood chemistry, and other factors.
Full blood count
Full blood count to establish the numbers of different blood cell types within the circulation. Low numbers of red or white blood cells are described as anemia or leukopenia, respectively. Read more
Staging
Most cancer patients are assigned a clinical "stage" after undergoing a diagnostic work-up. American physicians often use the four-stage TNM system - a classification system developed and recently revised by the American Joint Committee on Cancer (AJCC) and the Union Internationale Contre le Cancer (UICC; International Union Against Cancer). According to this system, staging is based on the size of the tumor and how far it has spread from its original location in the body.
Because leukemia starts in the bone marrow and often has spread to other organs by the time it is detected, there is no need for traditional staging. Instead, physicians rely upon cytologic (cellular) classification systems to identify the type and subtype of leukemia. Read more
Chemotherapy
Chemotherapy is a general term that is used to describe cancer-killing drugs. Such drugs can be given intravenously, through a vein; orally, by mouth; subcutaneously, injected under the skin; intramuscularly, injected into a muscle; or intrathecally, injected into the cerebrospinal fluid (CSF).
Chemotherapy for leukemia is varied, because there are many different forms of this disease. Read more