Cytogenetic Characteristics of Chronic Lymphocytic Leukemia Patients: A Single-Center Study From Morocco

Introduction and objective: Chronic lymphocytic leukemia (CLL) is the most common adult leukemia, characterized by significant clinical and biological heterogeneity. Cytogenetic abnormalities play a crucial prognostic role and influence treatment decisions. This study aimed to characterize the cytogenetic profile of CLL patients in a Moroccan tertiary hospital and to describe the distribution of major chromosomal abnormalities. Materials and methods: We conducted a retrospective descriptive study including patients diagnosed with CLL between January 2023 and December 2025 in the Hematology Department. Clinical, demographic, and cytogenetic data were collected from medical records. Cytogenetic analysis was performed using conventional karyotyping and/or fluorescence in situ hybridization (FISH), according to routine availability in daily practice. Results: A total of 53 patients were included, with a slight male predominance, comprising 28 (52.8%) men and 25 (47.2%) women, resulting in a male-to-female ratio of 1.12. The median age was 57 years, and the mean age was 56.2 years. Conventional karyotyping was performed in 20 of 53 patients (38%). Among the patients who underwent conventional karyotyping, 16 (80%) had a complex karyotype and four (20%) had a normal karyotype, corresponding to 30.2% and 7.5% of the overall cohort, respectively. FISH analysis was available for 46 (86.8%) patients and detected cytogenetic abnormalities in 24 (45.3%) patients. The most frequent abnormality was del(17p)/TP53, identified in 17 (47.2%) patients, followed by del(11q) in nine (25%) patients, del(13q14) in six (16.7%) patients, trisomy 12 in three (8.3%) patients, and del(14q) in one (2.8%) patient. Only one (2.8%) patient had an isolated 13q deletion, which is generally associated with a favorable prognosis. Conclusion: Cytogenetic abnormalities were frequent in this cohort, mainly TP53/17p deletion and complex karyotype. These results support routine cytogenetic assessment for accurate risk stratification and treatment planning in CLL.