Unveiling the Genetic and Immunophenotypic Landscape of Chronic Lymphocytic Leukemia in Indian Cohort

Chronic lymphocytic leukemia (CLL) is a biologically and clinically heterogeneous disease with variable progression and prognosis. The integration of Fluorescence in situ hybridization (FISH) findings with other prognostic markers such as IGHV mutational status and flow cytometry data is vital for accurate risk stratification and disease prognosis. This study focuses on analyzing the FISH and IGHV mutational status in an Indian cohort of B-CLL patients. 325 newly diagnosed CLL patients between August 2022 and May 2024 were included in this study. Diagnosis was based on standard guidelines and flow cytometry was used to confirm clonality of circulating B-cells. Afterwards FISH studies were performed on these samples to detect key chromosomal aberrations including deletion 13q14, trisomy 12, deletion 11q22 and deletion 17p13. Additionally, IGHV mutation status was assessed in 44 patients. Data were analyzed to understand the correlation of chromosomal aberrations, IGHV status, and clinical parameters. Deletion 13q was the most frequent aberration, observed in 167 cases, with 75% monoallelic and 25% biallelic deletions. The cells with deletion ranged from 7 to 98%.. Deletion 13q was seen coexisting with deletion 11q in 25 cases, trisomy 12 in 7 cases, and deletion 17p in 16 cases.. IGHV mutation analysis revealed that 25 out of 44 cases were mutated, with 13 of these cases having deletion 13q14 and 3 having trisomy 12. This study characterizes the genetic landscape of a cohort of Indian CLL patients through integrated cytogenetic and molecular analysis, highlighting recurrent aberrations and their distribution within the population.