RÉSUMÉ
Cancer in all forms is causing about 12% deaths throughout the world. After recent advances and improvement in treatment and prevention in cardiovascular diseases, tumour is an important cause of morbidity and mortality[1]. The incidence of leukaemia across the world is i per 100,000 annually. It contributes to 25% of childhood cancers[2]. The study was designed to investigate the Prevalence ofLeukemia subtypes at Lahore General Hospital/The Graduate Medical Institute, Lahore and was carried out in the Bone Marrow Clinic. The study was cross - sectional prospective. The period of the study was two year from 01 June, 2010 to 30 June, 2012. Complete blood counts, bone marrow aspiration and trephine biopsies were performed according to standard methods. In a total of 45 cases of leukaemia, acute leukemia was more prevalent than chronic leukaemia. The ratio of acute and chronic leukaemias was 4:1. Male to female ratio was 1.3: 1. Most of the patients [42%] were below the age of 15 years. ALL [49%] was more common than AML [31%]. Among chronic leukaemias, CML [16%] was more common than CLL [2%] and CMML [2%]. The study of acute leukaemia subtypes revealed that ALL - L[2] was more common [77%] than L[1] [24%]. In AML subtypes, M[3] [57%] was most prevalent while M[2] [14%] and M[4] [14%] and M[1] [7%] and M[6] [7%] were less prevalent of leukaemia subtypes. Acute leukaemias were more prevalent than chronic leukaemias. Leukaemias of all types were slightly more prevalent in male patients. ALL was more common than AML and was found to be a childhood malignancy. In leukaemia subtypes, ALL - L[2] and AML-M[3] were most common and in chronic leukaemias CML was most common