This cluster of papers focuses on the management, treatment, and complications of tumor lysis syndrome (TLS), a potentially life-threatening oncologic emergency characterized by metabolic disturbances. The papers cover various aspects including therapeutic strategies, classification, prophylaxis, risk evaluation, and the use of medications such as rasburicase and dapsone. Additionally, the cluster discusses related conditions like methemoglobinemia and hyperuricemia, particularly in pediatric and adult patients undergoing chemotherapy for hematologic malignancies.