Hemoadsorptionin Critically Ill Pediatric Oncology and Hemato-Oncology Patients: A Systematic Review with Structured...

Background: Critically ill children with cancer are vulnerable to sepsis and septic shock, secondary hemophagocytic lymphohistiocytosis (HLH), cytokine release syndrome, delayed chemotherapy clearance, and multiorgan dysfunction. Although hemoadsorption can remove inflammatory mediators and selected toxins, evidence in pediatric oncology remains limited and heterogeneous. Objective: To systematically review the indications, technical application, biomarker and physiologic findings, safety reporting, and clinical outcomes of hemoadsorption in critically ill pediatric oncology and hemato-oncology patients. Methods: We conducted a PRISMA-guided systematic review of PubMed, Scopus, and Web of Science from January 2017 to 1 June 2026, supplemented by reference screening. The search strategy was expanded to capture cartridge-based hemoadsorption and related extracorporeal blood purification modalities, including albumin dialysis systems, but direct synthesis was restricted to cartridge-based hemoadsorption. Evidence was stratified as direct pediatric oncology evidence, supportive hemato-oncology/transplant evidence, or contextual mixed pediatric critical-care evidence. Because included reports were small, uncontrolled, and clinically heterogeneous, synthesis followed a structured narrative approach without meta-analysis. Results: Twelve reports met the inclusion criteria; most were case reports, case series or retrospective observational studies. Hemoadsorption was most often described for septic shock, sepsis-like hyperinflammation, or secondary HLH, with smaller experience in delayed methotrexate clearance, CAR-T-cell-associated cytokine release syndrome, and post-transplant hyperbilirubinemia. Reported devices included CytoSorb, Jafron HA330, and HA230. Direct pediatric oncology reports described before-after reductions in IL-6, IL-10, C-reactive protein, procalcitonin, or ferritin, together with changes in oxygenation, vasoactive support, or organ dysfunction scores. However, all findings were vulnerable to confounding by concurrent antimicrobials, immunomodulation, kidney replacement therapy, source control, and natural recovery. Mortality outcomes were reported using non-equivalent horizons and were summarized narratively. Conclusions: Hemoadsorption has been attempted as adjunctive rescue support in selected critically ill pediatric oncology and hemato-oncology patients. Current evidence is insufficient to determine treatment effect, survival benefit, optimal timing, device selection, anticoagulation strategy, or pharmacokinetic safety.