Prevalence and Clinical Significance of SF3B1 Mutation in Sudanese Patients with Chronic Lymphocytic Leukemia

Background: The SF3B1 gene encodes a key component of the spliceosome and is recurrently mutated in chronic lymphocytic leukemia (CLL). These mutations have been linked to adverse prognosis and advanced disease stages in Western populations, but data from African cohorts remain scarce. Objectives: To determine the prevalence of SF3B1 mutations in Sudanese patients with CLL and assess their associations with demographic, clinical, hematologic, and morphological features. Methods: A cross-sectional study was conducted on 100 treatment-naïve CLL patients. Clinical staging was evaluated using Rai and Binet systems. Mutation detection was performed by allele-specific PCR. Hematologic indices and morphology parameters, including smudge cells, prolymphocytes, and composite morphology index (CMI), were compared between mutated and wild-type cases. Results: SF3B1 mutations were detected in 14% of patients. Mutated cases had significantly higher white blood cell counts (86.1 vs. 69.1 ×10⁹/L, p=0.027) and were more likely to present with advanced Rai stage (adjusted OR 2.58, p=0.031). Morphologically, SF3B1 mutations were associated with prolymphocytic features (35.7% vs. 8.1%, p=0.006) and high CMI scores (42.9% vs. 18.6%, p=0.039). No significant differences in hemoglobin or platelet counts were observed. Conclusion: SF3B1 mutations occur in 14% of Sudanese CLL patients and are independently associated with leukocytosis, prolymphocytic morphology, and advanced Rai stage. These findings reinforce SF3B1 as an adverse biomarker and support its integration into baseline prognostic evaluation in CLL.