LeukemiaLeukemia Zhou jianfeng M D Ph D Dept of Hematology TongJi Hospital leukemia is a group of cancers that originate in white blood cells called leukocytes leukemia is a clonal that is derived from a single cell malignant disorder affecting all age groups with an average annual incidence rate of 4 7 people per 100 000 It is characterized by the accumulation of immature blast cells in the bone marrow which replace normal marrow tissue including hematopoietichematopoietic precursor cells This results in bone marrow failure reflected by peripheral blood cytopenia and circulating blast cells Infiltration of various organs is also a feature of some forms of leukemia Leukemia is cancer that starts in the tissue that forms blood Most blood cells develop from cells in the bone marrow called stem cells Bone marrow is the soft material in the center of most bones To understand cancer it helps to know how normal blood cells form 1 Erythrocytes transport oxygenErythrocytes transport oxygen Neutrophil Basophil Eosinophil Monocytes Macrophage Defense against infectionDefense against infection Platelets Mediate blood clottingPlatelets Mediate blood clotting T lymphocytes antigen presenting T lymphocytes antigen presenting B lymphocytesB lymphocytes Plasma cell Plasma cell Source of antibodiesSource of antibodies