Acute leukemias are a type of cancer of unknown origin in most cases, that affects the blood cells, usually leukocytes. The disease occurs as a result of an error in the maturation process of a stem cell to white blood cell, which is a chromosomal abnormality that causes affected cells to become cancerous and multiply endlessly, infiltrating the bone marrow, where they replace cells that produce normal blood cells. These cancer cells spread through the blood, and can also invade other organs such as the liver, kidneys, lymph nodes, spleen and brain.
As the disease progresses, the malignant cells interferes with the production of other types of blood cells such as red blood cells and platelets, which results in the development of anemia and increased risk of infection.
Leukemias have an incidence of approximately two to three cases per 100,000 inhabitants per year. They are the most common cancers in children (about 25% of childhood cancers are leukemias), and most often affects men.
There appears to be substantial differences in the prevalence of leukemia among different races or geographic areas, rural or urban environment, or between different social classes. However, depending on the type of leukemia, his appearance is more common at certain ages. For example, in the case of acute lymphocytic leukemia (lymphoblastic), usually occurs in children between 3 and 5 years, but can also affect adolescents is rare in adults.