Joseph Latha Fathima, Ajmal Islam
Introduction: Chronic Myeloid Leukaemia (CML) is the most common myeloproliferative neoplasm and is characterised by presence of Philadelphia chromosome which results from a reciprocal balanced translocation between the chromosome 9 and 22(t9;22) resulting in the formation of Breakpoint Cluster Region - Abelson gene (BCR-ABL) fusion gene. Worldwide, the incidence of Chronic Myeloid Leukaemia (CML) is 1-2 per 100,000 population with a male predominance. The incidence increases with age. The median age of onset in middle-income groups is low. The age incidence is low in Asian countries. The present study was conducted to study the incidence and clinicohaematological profile of CML in South Indian population. Aim: To evaluate the haematological parameters of CML and to classify the phases of CML. Materials and Methods: The present 10-year descriptive crosssectional study from January 2014 to December 2023 was done at the Department of Transfusion Medicine & Immunohaematology in a tertiary care hospital in Bengaluru, Karnataka, India. Data were collected from the laboratory registers and Laboratory information system. Demographic data of patients across all age groups (1 to 100 years), along with findings from peripheral smear, bone marrow and molecular investigations were collected. Flow cytometry was done in cases with Blastic Phase (BP). Data was entered using Microsoft Excel and expressed as percentages and frequencies. Results: A total of 170 cases diagnosed with CML were included in the present study, with 155 adults and 15 children. Among the adult cases, male female ratio was 1.7:1. Highest incidence was observed in 31-40 age group (45.8%) with a male predominance (64.7%). The majority of adult patients presented in Chronic Phase (CP) (89.6%; 139/155), while 5.1% (8/155) were in HighRisk Chronic Phase (HRCP) and 5.1% (8/155) in BP. Among the 8 blast-phase cases, six were classified as myeloid blast crisis with MPO, CD 34, CD 13 and CD 117 positivity and two were B lymphoid blast crisis which are positive for CD 34, CD10, and CD 19. Of the 15 paediatric cases (0-18 years), five cases were below 10 years, and 10 cases were between 10 to 18 years. The male: female ratio in the paediatric age group was 1:1.5. Two children were in BP. Immunophenotyping confirmed lymphoid blast crisis. Conclusion: The current study demonstrates that the age of presentation of CML in Indian population is one to two decades earlier than that reported in Western population although the aetiology remains unclear. A mild male predominance was observed. CML was also encountered in paediatric age group, with two cases progressing to BP. Myeloid blast crisis constituted the majority of BP.