Leukemia in Sub-Saharan Africa: Systematic Review Maps 2,537 Cases

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A multi-institutional team with researchers based in Ghana and Australia published in Cancer Reports on July 31, 2026 a systematic review of leukemia epidemiology across sub-Saharan Africa pooling 2,537 cases from 32 studies to demonstrate that acute leukemias constitute nearly two-thirds of all reported diagnoses. The heterogeneous observational data limit definitive incidence estimates, yet the synthesis establishes a continental baseline for future cancer registry development.

The review appeared as multiple sub-Saharan African countries accelerate expansion of population-based cancer registry infrastructure.

2,537

Total Cases

64.8%

Acute Leukemia

37.3%

AML Share

English한국어

AI-generated conceptual illustration; not study data.

Continental Subtype Landscape From Five Decades of Evidence

The systematic review followed PRISMA guidelines and screened 94 candidate studies before retaining 32 that met predefined inclusion criteria spanning the period from 1975 to 2025. The included studies collectively reported 2,537 leukemia cases across multiple sub-Saharan African countries, providing a regional aggregation of reported cases. The geographic spread covers East, West, and parts of Southern Africa, though coverage remains uneven and several countries contributed no eligible data.

PRISMA-guided systematic review; 94 studies screened, 32 included; 1975 to 2025; sub-Saharan Africa. 2,537 leukemia cases reported across 32 included studies from multiple countries. All cases with available subtype classification; 244 unclassified cases noted separately. Leukemia subtype distribution, survival outcomes, and leukemia-related mortality.

AI-generated conceptual illustration; not study data.

Subtype analysis revealed that acute leukemias accounted for 1,644 cases, representing 64.8% of all classified diagnoses, while chronic leukemias comprised 893 cases. Among individual subtypes, acute myeloid leukemia was the most frequently reported at 947 cases, followed by chronic myeloid leukemia at 720 cases and acute lymphoblastic leukemia at 450 cases. Chronic lymphocytic leukemia accounted for 173 cases, with small numbers of acute undifferentiated leukemia and mixed phenotype acute leukemia also documented. Notably, 244 cases remained unclassified, reflecting the diagnostic limitations prevalent in many of the included studies.

Survival data varied enormously across the included studies, with reported outcomes ranging from as short as two weeks to as long as five years. The review documented 273 leukemia-related deaths, representing 10.76% of the total cohort, while 59 patients were lost to follow-up. Follow-up durations themselves ranged from 11 months to seven years, underscoring the heterogeneity of clinical monitoring across different healthcare settings and resource environments.

Implications for Regional Cancer Control and Diagnostic Equity

Leukemia represents a growing but poorly characterized burden in sub-Saharan Africa, where cancer registries cover only a fraction of the population and diagnostic infrastructure varies dramatically between urban tertiary centers and rural clinics. This review synthesizes reported subtype distributions across the included sub-Saharan African studies, offering a reference framework that national cancer control programs can use to benchmark their own data and identify diagnostic gaps. The predominance of acute myeloid leukemia and chronic myeloid leukemia in the aggregated data carries direct implications for treatment planning and resource allocation across the region.

Acute myeloid leukemia requires intensive induction chemotherapy and, in eligible patients, allogeneic stem cell transplantation, resources that remain scarce across much of the region. Chronic myeloid leukemia, by contrast, is manageable with tyrosine kinase inhibitors such as imatinib, yet access to these agents and to the molecular monitoring needed to track treatment response remains uneven. The finding that nearly ten percent of cases could not be classified at the subtype level highlights a critical diagnostic bottleneck that undermines both clinical care and epidemiological surveillance.

Without accurate subtype identification, clinicians cannot assign patients to appropriate treatment protocols, and epidemiologists cannot track meaningful trends over time. The review therefore underscores an urgent need for expanded immunophenotyping and cytogenetic testing capacity across the region, alongside investment in pathology workforce training and laboratory infrastructure. International partnerships and technology transfer initiatives will be essential to close these gaps within a meaningful timeframe.

Methodological Constraints and Interpretive Caution

The review carries substantial limitations that temper the strength of its conclusions. The 32 included studies span five decades and employ heterogeneous diagnostic criteria, ranging from morphology-only classification in older studies to immunophenotyping and cytogenetics in more recent ones. This temporal and methodological variation means that subtype proportions likely reflect diagnostic capability as much as true biological distribution. Readers should interpret the aggregated percentages as descriptive summaries rather than precise epidemiological estimates.

AI-generated conceptual illustration; not study data.

Survival data are particularly difficult to interpret across studies. The reported range of two weeks to five years captures everything from rapid mortality in untreated acute leukemia to long-term remission in well-managed chronic disease. Without standardized staging, risk stratification, or treatment protocol documentation, pooling these outcomes risks producing misleading averages. The 59 patients lost to follow-up further erode the completeness of survival estimates, and publication bias may skew the aggregated picture toward larger or more favorable case series.

The review did not perform meta-analytic pooling, a deliberate choice given the heterogeneity, but this means readers cannot derive summary effect sizes or confidence intervals from the data. Generalizability is also constrained, as the included studies disproportionately represent East and West African centers, with limited data from Central and Southern Africa. National-level incidence cannot be inferred from hospital-based case series, and the absence of population-based registry data means the true denominator of leukemia cases in the region remains unknown.

Priority Actions for the Regional Oncology Community

The authors identify several priority actions. First, they call for accelerated deployment of population-based cancer registries across sub-Saharan Africa, noting that fewer than half of countries in the region currently maintain functional registry infrastructure. Standardized data collection protocols, aligned with International Agency for Research on Cancer guidelines, would enable meaningful cross-country comparisons and trend analysis over time.

Second, the review highlights the need for diagnostic strengthening. Expanding access to flow cytometry, cytogenetics, and molecular diagnostics would reduce the proportion of unclassifiable cases and enable subtype-specific treatment planning. Training programs for pathologists and hematologists, coupled with telemedicine-based diagnostic support networks, could extend specialist expertise to underserved areas and improve the quality of future research outputs.

Third, the authors advocate for prospective, multicenter cohort studies that apply uniform diagnostic and treatment protocols across multiple countries. Such studies would generate the high-quality evidence base needed to develop region-specific clinical guidelines and to evaluate the effectiveness of adapted treatment protocols in resource-constrained settings. The establishment of collaborative research networks, building on existing frameworks such as the African Organisation for Research and Training in Cancer, would provide the organizational foundation for these efforts and accelerate progress toward equitable cancer care.

This review synthesizes published observational data and does not generate new primary evidence. All numeric findings derive from the 32 included studies as reported by their original authors. The aggregated figures should not be interpreted as population-based incidence or survival rates. No individual patient data were accessed or re-analyzed. Conclusions are limited by the heterogeneity and quality of the underlying evidence base, and no causal inferences can be drawn from the descriptive summaries presented here.

Primary source: PubMed record for the systematic review. https://pubmed.ncbi.nlm.nih.gov/42535976/. Publisher full text: https://doi.org/10.1002/cnr2.70635.

This article is not medical advice. It summarizes a published systematic review for general educational purposes. Treatment decisions for leukemia require individualized assessment by qualified hematologists and oncologists. Readers in sub-Saharan Africa seeking diagnostic or treatment information should consult their national cancer control programs or treating physicians. No commercial relationships influenced this summary.