Circulating plasma EBV DNA: a potential tool to facilitate diagnosis of pediatric Burkitt lymphoma in sub-Saharan Africa Open Access

• Plasma EBV DNA copy number discriminated BL cases from healthy children in East Africa with sensitivity, specificity, accuracy above 80%.

• Circulating EBV DNA copy number could facilitate diagnosis of BL earlier, reduce diagnostic delays, and increase BL cure in Africa.

Due to diagnostic delays in sub-Saharan Africa, many pediatric patients with Burkitt lymphoma (BL) perish. A subtype of BL, accounting for 95% of pediatric BL cases in sub-Saharan Africa, is characterized by the presence of Epstein-Barr Virus (EBV). We assessed plasma EBV DNA in 400 BL cases and 400 controls frequency-matched on sex, age, and country enrolled in the Epidemiology of Burkitt lymphoma in East African Children and Minors (EMBLEM) study in Uganda, Kenya, and Tanzania (2010-2016). EBV was measured using digital droplet PCR assay targeting EBV BamH1-W internal repeats, duplexed with RPP30 human housekeeping gene. The study population was predominately male (63% of cases and 64% of controls), with an average age of approximately 7.5 years. EBV DNA was detected in 309 (77.3%) BL cases and 62 (15.5%) controls. The mean plasma EBV DNA levels were 5.00 (standard deviation [SD] 1.63) log₁₀ copies/mL for BL cases versus 1.94 (SD 1.35) for controls (p<0.0001). Excluding 50 BL cases and 61 controls with indeterminate (RPP30 and EBV negative) samples, the maximum sensitivity of plasma EBV DNA detection to discriminate BL cases from controls was 88.3% (95% CI 84.4-91.5%), with 81.7% (77.2-85.7%) specificity, and area under the curve 91.9% (89.7-93.9%). A specificity of 100% was achieved at a threshold of 4.19 log₁₀ EBV copies/mL, which reduced sensitivity to 66.6%. Assay accuracy varied from 83%-87.4% at different thresholds. Testing for EBV DNA could facilitate the recognition of BL earlier in sub-Saharan Africa, a critical step in improving BL cure rates in the region.