Comparison of early mortality between leukapheresis and non-leukapheresis in adult acute myeloid leukemia patients with hyperleukocytosis: a systematic review and meta-analysis

Objectives: One of the treatment modalities that can be used for hyperleukocytosis is leukapheresis. However, the result of studies showing the benefit of early mortality through the use of leukapheresis versus no leukapheresis is still inconclusive. Hence, we aimed to conduct a systematic review with meta-analysis to determine the effect of leukapheresis on early mortality in AML patients with hyperleukocytosis. Methods: We conducted a literature search on five databases (PubMed, EBSCOhost, Scopus, Clinicalkey, and JSTOR) up to October 2021 for studies comparing early mortality outcomes between hyperleukocytosis AML patients treated with leukapheresis versus no leukapheresis. Summary odds ratios (OR) and 95% confidence intervals (CI) were calculated using random-effects models. Heterogeneity tests were presented in I² value and publication bias was analyzed using a funnel plot. Results: Eleven retrospective cohort studies were eligible based on the inclusion and exclusion criteria. Pooled analysis showed that there was no significant difference in early mortality between patients receiving leukapheresis and not receiving leukapheresis in studies using hyperleukocytosis cutoff of 95,000/mm³ or 100,000/mm³ (OR: 1.17; 95% CI: 0.74-1.86; p: 0.50; I²: 0%). Similarly, studies using hyperleukocytosis cutoff of 50,000/mm³ also showed no benefits of early mortality (OR: 0.67; 95% CI: 0.43-1.05; p: 0.08; I²: 0%). Most of the studies used had a moderate risk of bias due to being observational studies. Funnel plot showed an indication of publication bias on studies using hyperleukocytosis cutoff of ≥50,000/mm³. Conclusion: The use of leukapheresis does not provide early mortality benefit in adult AML patients with hyperleukocytosis.