Tumor Lysis Syndrome, CTCAE 6.0

**Semantic type:** Finding

**Definition:** A disorder characterized by metabolic abnormalities that result from a spontaneous or therapy-related cytolysis of tumor cells. Clinical tumor lysis syndrome (CTLS) requires one or more clinical manifestations along with criteria for laboratory tumor lysis syndrome (LTLS). LTLS is defined by two or more of the following laboratory abnormalities within 3 days before or 7 days after the initiation of chemotherapy: Uric acid >= 476 mcmol/L or 25% increase from baseline, Potassium >= 6.0 mmol/L or 25% increase from baseline, Phosphorous >= 2.1 mmol/L (children), >=1.45 mmol/L (adults) or 25% increase from baseline, Calcium <= 1.75 mmol/L or 25% decrease from baseline.

**Synonyms:** - Tumor lysis syndrome