Guidelines for Complications of Cancer Treatment Vol VIII Part B

Tumor Lysis SyndromeDefinition: Tumor lysis syndrome (TLS) is characterized bya group of metabolic derangements including hyperuricemia,hyperkalemia, hyperphosphatemia, hypocalcemia, anduremia.caused by the massive and abrupt release of cellularcomponents into the blood after the rapid lysis of malignantcells. It is observed most frequently in patients withmalignancies with high proliferative rate, large tumor burden,or high sensitivity to cytotoxic therapy such as acutelymphoblastic leukemia (ALL) and Burkitt’s lymphoma afterthe initiation of cytotoxic therapy.Pathogenesis and Clinical ConsequencesThe release of intracellular metabolites, including nucleicacids, proteins, phosphorus, and potassium after the initiationof cytotoxic chemotherapy or cytolytic antibody therapy canoverwhelm normal homeostatic mechanisms, potentiallyleading to hyperuricemia, hyperkalemia, hyperphosphatemia,hypocalcemia, and uremia. In some cases, TLS can lead toacute renal failure and even death due to uric acid or calciumphosphate precipitation, xanthine crystallization, tumorinfiltration in the kidney, tumor-associated obstructiveuropathy, drug associated nephrotoxicity, and/or acute sepsis.420