Leukemia (leukemia) is a malignantdisease of white blood cells. The disease occurs in the bone marrow and then spreads in the blood, lymph nodes, spleen, liver, central nervous system (CNS) and other organs. Leukemia can occur in both children and adults.
Leukemia is a complex disease and ismany different types and subtypes. The type of treatment and outcome vary widely depending on the type of leukemia and other individual factors.
Blood and lymphatic system
To understand the different types of leukemia is useful to have basic information about the circulatory and lymphatic systems.
Bone marrow - A soft, spongy, inner part of bones. All blood cells produced in the bone marrow. In infants, the bone marrow is found in almost all body bones. By adolescence, the bone marrow is stored mainly in the flat bones of the skull, shoulder blades, ribs, pelvis.
Bone marrow contains cells kroveobrazuyuschie,fat cells and tissues, helping the growth of blood cells. The early (primitive) blood cells are called stem cells. These stem cells are grown (mature) in a specific order and produce red blood cells (erythrocytes), white blood cells (leukocytes) and platelets.
Red blood cells blood carry oxygen from the lungs to other tissuesbody. They also removes carbon dioxide, the waste product of cell activity. Reducing the number of red blood cells (anemia, anemia) causes fatigue, shortness of breath and fatigue.
White blood cells Blood helps to protect the body from germs,bacteria and viruses. There are three main types of white blood cells: granulocytes, monocytes and lymphocytes. Each type has a special role in protecting the body against infection.
Platelets prevent bleeding for cuts and bruises.
The lymphatic system It consists of lymph vessels, lymph nodes and lymph.
Lymphatic vessels They resemble veins, but are not blood and clear fluid -limfu.
Lymph It consists of excess tissue fluid, waste products and cells of the immune system.
The lymph nodes (Sometimes called lymph glands) -bean-shaped organs located along the lymphatic vessels. Lymph nodes contain cells of the immune system. They can often grow in size during inflammation, especially in children, but they sometimes increase may be an indication of leukemia tumor process when left outside of the bone marrow.
What causes acute leukemia, and whether they can be prevented
Risk Factor - this is what increases the likelihood of disease. From some risk factors, such as smoking, can be eliminated. Other factors, such as age, can not be changed.
Smoking is a proven risk factor foracute myeloid leukemia (AML). While many people know that smoking causes lung cancer, few realize that smoking can affect the cells that are not directly in contact with the smoke.
Substances that cause cancer, and containedtobacco smoke, enter the bloodstream and spread throughout the body. One-fifth of cases of AML is caused by smoking. Smokers need to take a smoking cessation attempt.
There are certain environmental factors,which are linked to the development of acute leukemia. For example, prolonged contact with gasoline is a risk factor for AML, and exposure to high doses of radiation (atomic bomb or nuclear reactor accident) increases the risk of AML and acute lymphoblastic leukemia (ALL).
In people who suffer from other malignanttumors and treated with some anticancer drugs, increased risk of AML. Most cases of AML occurs 9 years following treatment of Hodgkin's disease (Hodgkin's disease), non-Hodgkin's lymphoma (lymphosarcoma), ALL or other malignancies, for example breast and ovarian cancer.
There is some concerna relatively high voltage transmission lines as a risk factor for leukemia. According to some reports, in these situations, the risk of leukemia is not raised or increased slightly. What is clear is that most cases of leukemia is not associated with high-voltage transmission lines.
A small number of people suffering from very rare diseases or HTLV-1 virus, the risk of acute leukemia increased.
However, most people with leukemia was notidentified risk factors. The cause of their illness remains unknown to date. Due to the fact that the cause of leukemia is not clear, then there is no way of prevention, except for two important points: avoid smoking and substances that cause cancer, such as gasoline.
As classified leukemias
In most tumors secrete stagediseases (I, II, III and IV), which are based on the size of the tumor and its prevalence. This is not suitable for staging leukemia because leukemia - a disease of blood cells, which typically does not form tumor mass.
Leukemia affects the entire bone marrow, and in manycases to the moment of diagnosis already involves other organs in the process. In laboratory studies leukemia tumor cells allow to specify their characteristics, which help in the outcome (prognosis) of the disease assessment and selection of treatment.
Emphasis three subtypes of acute lymphoblastic leukemia and eight subtypes of acute myeloid leukemia.
Different types of leukemia
There are four main types of leukemia:
- acute versus chronic
- lymphoblastic compared to myeloid
"Acute" means booming. Although the cells grow rapidly, they are not able to mature properly.
"Chronic" means a condition where the cells look mature but, in fact, they are abnormal (altered). These cells live too long and replace some types of white blood cells.
"Lymphoblast" and "myeloid" refers to twovarious types of cells, which originated from leukemia. Lymphoblastic leukemia develops from bone marrow lymphocytes, myeloid leukemia arises from granulocytes or monocytes.
Leukemia can occur in both children and adults, but the different types of leukemia prevail in one or another group.
Acute lymphoblastic leukemia (ALL)
- It occurs in children and adults;
- Most often diagnosed in children;
- It makes a little more than half of all cases of leukemia in children.
Acute myeloid leukemia (AML) (often called acute leukemia nelimfoblastnyh)
- It affects both children and adults;
- It is less than half of all cases of leukemia in children.
Chronic lymphocytic leukemia (CLL)
- It occurs only in adults;
- It reveals twice as often chronic myeloid leukemia (CML).
Chronic myeloid leukemia (CML)
- Mainly affects adults and is rarely diagnosed in children;
- Diagnosed two less CLL.