Leukemia is a malignant disease (cancer) characterized by an abnormal accumulation of white blood cells in the body. Leukemia usually begins in the bone marrow and spreads to other parts of the body. This disease can affects both children and adults.
Types of Leukemia
In general, leukemia are classified into two main categories: Myelogenous leukemia and Lymphocytic leukemia. The terms myelogenous or lymphocytic indicates the type of cells involved.
Myelogenous leukemia develops from myeloid cells, while lymphocytic leukemia develops from cells called “lymphoblasts” or “lymphocytes” in the bone marrow. Each of the types can be acute (rapidly developing) or chronic (slowly developing). So, there are four major types of leukemia:
- Acute Lymphocytic Leukemia (ALL)
Acute lymphocytic leukemia is a cancer of the blood in which too many lymphocytes, a type of white blood cell, are produced by the bone marrow and other parts of the body.
Acute Lymphocytic Leukemia usually affects children aged 3 to 7. It is the most common form of leukemia in children. However, the disease may also occurs in adults, especially those aged 65 and older.
Treatments for Acute Lymphocytic Leukemia include chemotherapy and radiation therapy. Some of the types of Acute Lymphocytic Leukemia include acute biphenotypic leukemia, Burkitt’s leukemia, precursor B acute lymphoblastic leukemia, and precursor T acute lymphoblastic leukemia.
- Chronic Lymphocytic Leukemia (CLL)
Chronic lymphocytic leukemia is similar to Acute Lymphocytic Leukemia (ALL), but it is more common in adults, often occurs during or after middle age; it rarely occurs in children. There is no cure for this disease, but there are many effective treatments. One of the most serious type of Chronic Lymphocytic Leukemia is B-cell prolymphocytic leukemia.
- Acute Myelogenous Leukemia (AML)
Acute myelogenous leukemia, also called granulocytic or myelocytic, is a cancer of the blood in which too many granulocytes, a type of white blood cell, are produced in the bone marrow.
Acute myelogenous leukemia typically occurs in adults and men. Women and children are rarely affected. A treatment option for acute myelogenous leukemia is chemotherapy. Types of Acute myelogenous leukemia include acute megakaryoblastic leukemia, acute myeloblastic leukemia, and acute promyelocytic leukemia.
- Chronic Myelogenous Leukemia (CML)
Chronic Myelogenous Leukemia is one way a special cancer: in almost every case, the underlying cause of this disease is known. In CML, the two DNA regions that normally are not next to each other are merged, creating an uncommon protein found in the body that can induce stem cells develop into granulocytes.
Chronic myelogenous leukemia mainly affects adults, but a very small number of children may also develop this disease. Chronic myelogenous leukemia is treated with a drug called “Imatinib (Gleevec)”. A type of chronic myelogenous leukemia is chronic monocytic leukemia.
Causes and Risk Factors for Leukemia
The exact causes of leukemia are not yet clearly identified. However, researches suggest that there are some risk factors are linked to leukemia. The risk factors for leukemia include:
- Having Family history of leukemia
- Having chemotherapy and/or radiotherapy for other cancers
- Diagnosing with blood disorders, such as myelodysplastic syndromes
- Suffering from certain genetic diseases, such as Down syndrome
- Exposure to high levels of radiation
- Exposure to certain chemicals such as benzene, which is found in gasoline and is used by the chemical industry.