Clinical, Haematological and Flow-Cytometric Profile of Classical Chronic Lymphocytic Leukaemia With Matutes Score-Based Subgroup Analysis: A Single-Centre Study

Abstract Background Chronic lymphocytic leukaemia (CLL) is diagnosed by integrating persistent lymphocytosis, morphology and flow-cytometric immunophenotyping. Detailed Sri Lankan data remain limited. Purpose To describe the clinical, haematological, morphological and flow-cytometric profile of classical CLL and to explore differences across Matutes score groups. Methods This descriptive cross-sectional study included 94 diagnosed classical CLL cases at Sri Jayewardenepura General Hospital, Sri Lanka. Demographic and clinical features, full blood count, morphology, lymphocyte subsets, qualitative marker expression, fluorescence-intensity metrics and CD45 indices were analysed. Matutes 3/5, 4/5 and 5/5 groups were compared using Kruskal-Wallis and Fisher-Freeman-Halton exact tests. Results Median age was 66.0 years (IQR 59.0–71.8), 57/94 (60.6%) were male, and persistent lymphocytosis was present in 93/94 (98.9%). Morphology was typical, with predominantly small to small-medium lymphoid cells, absent nucleoli and smooth nuclear contours. CD19 and CD5 were expressed in all cases; CD23, CD200 and CD43 were frequent, while FMC7 and CD79b were commonly negative or weak. Matutes scores were 3/5 in 31 (33.0%), 4/5 in 39 (41.5%) and 5/5 in 24 (25.5%). Score groups differed for age, CD19-gated B-cell percentage, CD4/CD8 ratio and CD45 index; hepatomegaly, CD200 positivity and CD38 positivity also differed across groups. Conclusions This study showed typical clinical, morphological and immunophenotypic features of classical CLL. Matutes-score groups differed in selected clinical and flow-cytometric parameters, while morphology remained similar. CD45-index variation may reflect immunophenotypic differences, but its diagnostic significance requires further validation in larger, multicentre studies.