Background: Tumor lysis syndrome (TLS) is a potentially life-threatening condition resulting from the rapid destruction of malignant cells, leading to electrolyte imbalances and severe complications, such as acute kidney injury, arrhythmias, and seizures. TLS can be managed through hyperhydration, urate-lowering treatments, and a steroid prophase strategy.

Aims: This study aims to explore the impact of fractionated rituximab, an anti-CD20 antibody, on the occurrence and severity of TLS during the initial cycle in patients with aggressive B-cell non-Hodgkin lymphoma (B-NHL).

Methods: Data was retrospectively collected from 94 of 186 patients.

Results: Among the 94 patients included in the analysis, the median age was 70. Histologies were diffuse large B-cell lymphoma (75%), Burkitt lymphoma (13%) and high-grade B-cell lymphoma (8%). The majority were at an advanced stage (93%) with a high IPI score (75%). Most patients received anthracycline-containing regimens (72%) and prophylactic allopurinol (83%) and/or rasburicase (26%). Steroid prophase was administered to 82% of patients. The study identified one clinical TLS case and six laboratory TLS cases. Significant TLS factors included BL histology, elevated baseline LDH (⟩500 U/l), and rasburicase usage. Infusion reactions were rare (3%). Median progression-free survival was 2.6 years, and 2-year overall survival was 33%, irrespective of TLS occurrence.

Conclusion: In this real-life study, clinical TLS occurrence was low (1%). TLS appeared more frequent in BL but did not impact overall survival. Fractionated initial rituximab dosing in addition to preventive strategies is a feasible approach in preventing clinical TLS, warranting further prospective investigation.