Pooled proportion of hematological malignancies among pediatric cancer patients in Ethiopia: systematic review and meta-analysis

Background Pediatric hematological malignancies constitute a major component of childhood cancers globally and are important contributors to childhood morbidity and mortality. However, their overall proportion among pediatric cancer patients in Ethiopia has not been quantified. This systematic review and meta-analysis aimed to estimate the pooled proportion of hematological malignancies among pediatric cancer patients in Ethiopia. Methods A systematic review and meta-analysis was conducted in accordance with the PRISMA 2020 guidelines, and a comprehensive search of PubMed, HINARI, ScienceDirect, Semantic Scholar, African Journals Online, Google Scholar, and Google was performed from each database’s earliest available record through August 28, 2025. Eligible studies included cross-sectional, and cohort designs reporting leukemia and lymphoma among children aged birth to 18 years. Study quality was assessed using Joanna Briggs Institute critical appraisal tools. A Šidák-Jonkman random-effects model was used to estimate the pooled proportion via STATA version 17. Heterogeneity was assessed using Cochran’s Q and I² statistics. Subgroup analyses, meta-regression, sensitivity analyses, and assessment of publication bias were performed. Results Thirteen studies encompassing 7,460 pediatric cancer patients were included in the analysis. The pooled proportion of hematological malignancies among pediatric cancer patients was 51.49% (95% CI: 44.97%-58.00%). Considerable between-study heterogeneity was observed (I² = 95.80%, p < 0.001), with a 95% prediction interval ranging from 25.54% to 77.44%. Subgroup analyses suggested variation according to study design, sample size, and study period. Meta-regression indicated that study design and study-period midpoint explained part of the observed heterogeneity, although these associations were not robust in sensitivity analyses. Leave-one-out analyses demonstrated the stability of the pooled estimate, and Egger’s test showed no statistically significant evidence of small-study effects (p = 0.655). Conclusion Hematological malignancies accounted for approximately one-half of pediatric cancer cases reported in the included Ethiopian hospital-based studies. However, substantial heterogeneity and the predominance of hospital-based evidence limit the generalizability of the pooled estimate to the national population. Future studies could employ prospective, population-based designs with standardized diagnostic and reporting approaches, alongside strengthened cancer registries, surveillance systems, referral pathways, and pediatric hematology-oncology capacity in Ethiopia. Clinical trial number. Not applicable.