A large number of cases of cancer are identified to be leukemia. Leukemia is a sort of cancer of the blood and marrow. The disease is characterized through the overproducing of immature blood cells (stem cells) that are not able to fully develop and to carry out the activities of normal blood cells. According to their functions and structure, there are three different types of cells within the normal blood: red blood cells, white blood cells and platelets. Through the process of hematopoiesis, these three types of blood cells are developed from a distinctive type of blood cell called stem cell. Stem cells divide and go through several stages of development to finally form a mature blood cell of a particular type, with a certain, distinctive function in the body.
The process through which a stem cell morphs into a mature blood cell takes place within the bone marrow. According to the speed of development and the persistence of the disorder, there are two types of leukemia: acute leukemia and chronic leukemia. Acute leukemia is known to develop very rapidly, while Chronic leukemia is developed slowly. According to the types of blood cells affected by the disease, leukemia can either be lymphocytic or myelogenous.
Lymphocytic and myelogenous types of leukemia are developed from different types of cells: the lymphocytic type of leukemia develops from cells called lymphoblasts or lymphocytes in the spongious tissue of the bones, while the myelogenous type of leukemia (sometimes refered to as myeloid and myelocytic leukemia) develops from myeloid cells. In the case of acute forms of leukemia, the abnormal cells come from early, immature cells. Such forms of the disorder have a very fast rate of development, due to the fact that normal stem cells tend to multiply frequently. Leukemia cells usually don’t divide faster and more frequently than normal stem cells, they simply don’t stop their process of division when they should.
Sometimes the numbers of white blood cells are very high, while in other cases they can be normal or low. Chronic leukemia, apart from its slow development, is different from acute leukemia by the level of maturation that the diseased cells are able to reach. Stem cells affected by chronic leukemia reach a higher level of maturation but they present abnormalities and they can’t act as healthy white blood cells do. Unlike acute leukemia, in the chronic form of the disease the unhealthy cells have much longer periods of life and they tend to accumulate in different parts of the body. Leukemia affects people of all age groups.
While children usually respond better to the treatment for leukemia and sometimes deal well with the disease, adults have difficulty to cope with this form of cancer. Regardless of age and sex, many people are diagnosed with different forms of leukemia. The cases of acute leukemia exceed those of chronic leukemia by approximately 10 percent. Older adults seem to be affected the most by acute leukemia. Around two thirds of acute leukemia cases seem to occur after the age of 60.
Possible Leukemia Causes and Risk Factors Leukemia is a disease that is considered to be life-threatening. It requires prompt intervention when discovered, in order to maximize the chances of recovering through specific treatment and therapy. Leukemia is basically a type of cancer of the bone marrow and blood, caused by inappropriate cellular activity. The direct causes of leukemia are still unknown. At present, medical science isn’t able to establish the specific leukemia causes. However, a strong connection between certain genetic factors and the development of the disease has been revealed. Leukemia occurs on the background of genetic failure that causes the excessive production of incomplete, partially matured blood cells.
Also, leukemia has a hereditary character, allowing the transmission of genetic predispositions to disease from one generation to another. Although many factors are known to contribute to the development of leukemia, they alone can’t be considered as causes. Despite the fact that statistics indicate a higher incidence of the disease in people that are exposed to some environmental factors of risk, leukemia does not seem to be caused by neither of them in particular.
Among the environmental factors that are thought to be leukemia causes, here are some of the most plausible ones:
- Smoking – smoking is thought to increase the chances of being affected by leukemia. Although statistics show that around 20 percent of acute leukemia cases are related to smoking, it also affects people that don’t smoke.
- Prolonged exposure to radiation – Radiation is considered to facilitate the development of leukemia. It is believed that extended exposure to X-rays can be a cause;
- Prolonged exposure to benzene – statistics reveal that this is a major factor of risk in some forms of leukemia, such as myelogenous leukemia;
- Chemotherapy and cancer treatment – previous cancer treatments and chemotherapy are known to facilitate the occurrence and development of leukemia and can be considered plausible leukemia causes. Within a few years from the completion of chemotherapy and other treatments for certain forms of cancer, people can develop leukemia.
Among the genetic factors that are considered to be leukemia causes, the following ones are thought to be the most important:
- chromosome abnormalities – some rare genetic syndromes are known to contribute to leukemia causes;
- Immune system genetic problems - a weak immune system is very likely to facilitate the occurrence of leukemia and therefore can be considered a leukemia cause;
- Down syndrome – children born with this syndrome have a very high risk of developing acute leukemia. The list of possible leukemia causes can continue further, but these are the most common factors that are considered to be interrelated with leukemia. While some of them can be prevented, others reside within the genes and at present can’t be corrected. In future, however, thanks to medical advance, we will probably be able to prevent leukemia and other forms of cancer.