Leukemia is the blood cancer form and originates in a malfunctioning bone marrow that tends to produce abnormal red and white cells in an increased rate. The most important four types of Leukemia are the acute and chronic myelogenous leukemia and the acute and chronic lymphocytic Leukemia. The name of the condition stands for the cell type involved.

The acute type of leukemia develops with an increased production of abnormal white cells making the body unable to fight infections; red blood cells and platelets are insufficient and the organism suffers from bruising, bleedings and anemia. Chronic forms of Leukemia are not as aggressive as they give the normal cells time to regenerate.

About 25000 new equal cases of acute and chronic Leukemia appear every ear. Most cases appear in adults and persons over 60 years but the acute lymphocytic Leukemia has an increased rate in children. Annually, about 10000 cases in adults are diagnosed as acute myelogenic Leukemia, 8000 are chronic lymphocytic Leukemia, 500 are chronic myelogenous forms and about 3500 are acute forms of lymphocytic Leukemia. The rest of the cases are unclassified blood cancer types.

All types of Leukemia are most commonly encountered in men than in women. Men subjects cover about 56% of all Leukemia new cases in a year. Americans with European descent seem to be more affected by cancer than those with African origins; about 131000 new cases of cancer are detected in African Americans every year but most of them are not related to blood cancers.

Americans with Indian or Hispanic origins are far more affected by Leukemia than African Americans and about 50% of the cases are encountered in male subjects. Elderly persons are most highly affected inside all populations.
Minority groups like Caucasians are more affected by Leukemia forms than other ethnic groups like Chinese, Japanese and Koreans. European descent children show increased rate of susceptibility compared to African American children.

Most of the new occurred cases of cancer in children below 15 are of Leukemia. About 2500 new cases of acute forms of lymphocytic leukemia are identified in the USA annually and it tends to be the most encountered form of cancer in children. High percents of the cases occur in children aged 3-4 and less in infants or 19 years old patients. In the last 25 years the chance of cure in specialized centers has increased due to new therapy methods.

People over 40 and older persons are more touched by acute myelogenous Leukemia and the secondary Leukemia type found in adults is chronic lymphocytic leukemia.