Leukaemia blood cells. Light micrograph of blood showing numerous white blood cells (WBCs, blue) due to leukaemia. Red blood cells are grey. Leukaemia is a form of cancer in which excessive amounts of abnormal WBCs are produced, leading to a reduction in the numbers of red blood cells and platelets. Lack of red blood cells leads to anaemia. Frequent bruising and bleeding occurs due to a lack of platelets. Serious infections may also occur as the leukaemic WBCs do not attack foreign organisms as healthy WBCs do. Leukaemia is treated with chemo- and radiotherapy and blood transfusions. Magnification: x240 at 6x4.5cm size.