Tumour lysis syndrome (TLS) - -Uric acid, phosphate and potassium are released in large quantities from death of tumour cells. -Hyperuricemia can lead to impairment of renal function, which fuher exacerbates the metabolic abnormalities. -Hypocalcaemia is a consequence of acute hyperphosphatemia with subsequent precipitation of calcium phosphate in soft tissues. 'TLS can occur before therapy in patients with a large tumour burden (e.g., Burkitt lymphoma, Hyperleukocytosis) It is usually seen within 12-48 hr of initiating chemotherapy.