Cancer is a disease caused by uncontrolled division of abnormal cells in various parts of the body. Leukemia is a group of cancers that mutant bone marrow and result in high numbers of abnormal white blood cells. Leukemia has many origins. Its symptoms may include the ability to be easily bruised, feeling tired, fever, and an increased risk of infections. Leukemia has the highest incidence in Europe and North America with a mortality rate of 3.2-7.4% per 100,000 population. Maria Curie died of leukemia in 1934. There are four main types of leukemia —acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), chronic lymphocytic leukemia (CLL) and chronic myeloid leukemia (CML).