The Biology of Chronic Myelogenous Leukemia in Childhood and Young Adolescents: An Indian Perspective

Objective: The purpose of this study was to determine the clinical, biological, and molecular characteristics at diagnosis in children and adolescents with chronic myelogenous leukemia (CML) in the Indian scenario at our tertiary patient care center. Subjects and Methods: We evaluated 51 children and adolescents with CML registered at our clinic, from January 2007 to December 2015. The mean and median of various parameters were calculated using a Microsoft excel sheet and SPSS software version 16. Results: The median age of presentation in children was 16 years; 92.2% of them were older than 10 years, with a higher prevalence in boys than girls (gender ratio 2.6:1). The symptoms at presentation were fatigue, fever, awareness of mass due to splenomegaly, and bleeding manifestations. One patient presented with Bell's palsy. Markedly raised leukocyte counts were present in 29.4% patients (median white blood cell count >400 × 109/L). Most of the patients presented in the chronic phase of the disease, four each were in accelerated phase and blast crisis, respectively. Majority of patients were categorized as intermediate risk as per Sokal and Hansford score. About 60.7% of these pediatric patients fell in low-risk category as per European Treatment and Outcome Study score at baseline. A predominance of transcript P210-b3a2 (68%) was observed in the children who were studied for the type of chimeric BCR-ABL mRNA. Conclusions: This is one of the most recent reported series of CML in children and adolescents from India highlighting the difference in presentation from adults; mainly hepatomegaly, bleeding manifestations, and higher leukocyte count. Presence of b3a3 transcript of p210 breakpoint of BCR-ABL was more common in children (68%) than b2a2 transcript (32%) when compared to adults as recently described in a study from India, which may explain the differences at presentation.