Leukaemia is the most common childhood cancer and accounts for over 30% of all cancers diagnosed in children aged below 15 years old in the world (IARC, 2012). Causes of leukaemia are not well known, but some known risk factors include inherited factors such as Down syndrome and a family history of leukaemia and non-inherited factors including exposure to inonising radiation. There are different types of leukaemia but about three-quarters of cases among children are acute lymphoblastic leukaemia (ALL). The second most frequent type is acute myeloid leukaemia. Prognosis of leukaemia is different depending on various factors including age, initial white blood cell count, gender, initial reaction to induction treatment and type of leukaemia. Children with acute leukaemia who are free of the disease for 5 years are considered to have been cured as remission after 5 years is rare.