Epidemiological Profile of Hematological Malignancies at a Tertiary Referral Center in Jeddah, Saudi Arabia: A Retrospective Cohort Study

Abstract: BACKGROUND: Hematological malignancies represent a heterogeneous group of disorders with variable epidemiology across ethnic and geographic populations. Data from Saudi Arabia and the broader Middle East remain sparse, particularly from centers serving large migrant populations. OBJECTIVES: To describe the demographic characteristics of patients with hematological malignancies at a tertiary referral center in Jeddah, to determine the relative frequency and distribution of major hematological malignancy categories, and to characterize age and sex distribution across diagnostic groups. METHODS: A retrospective registry-based cohort study was conducted on 1,569 patient records registered at a hematology department in Jeddah between 2010 and 2021. Diagnoses were reclassified according to the World Health Organization 2016 criteria, the classification in use at the time of data coding. Descriptive statistics were used to characterize the cohort. RESULTS: The cohort comprised 1569 patients (57.1% male; M:F ratio: 1.33:1) with a mean age of 41.1 ± 24.2 years (range: 0–101). Non-Hodgkin lymphoma (HL) was the most common diagnosis (456 cases; 29.1%), followed by acute lymphoblastic leukemia (236; 15.0%), plasma cell disorders including monoclonal gammopathy of undetermined significance (184; 11.7%), and HL (176; 11.2%). Non-Saudi patients constituted 67.7% of the cohort, with Yemeni (22.6%), Pakistani (6.9%), and Syrian (5.5%) nationals being the most represented non-Saudi groups. A female predominance was observed in myeloproliferative neoplasms (56.5%) and myelodysplastic syndromes (61.7%). CONCLUSION: This single-center cohort provides a contemporary epidemiological snapshot of hematological malignancies in a diverse Middle Eastern tertiary center. The high proportion of lymphoid malignancies and the multiethnic patient composition underscore the need for region-specific registries and prospective data collection to inform healthcare planning and resource allocation.