Tumor Lysis Syndrome — Acute Metabolic Cancer Emergency

Tumor lysis syndrome is an oncologic emergency characterised by rapid, massive destruction of malignant cells. As intracellular components enter the systemic circulation, they overwhelm the body's homeostatic mechanisms, resulting in distinct metabolic disturbances: hyperkalaemia, hyperphosphataemia, hyperuricaemia, and secondary hypocalcaemia.

These biochemical imbalances can precipitate severe physiological crises. Elevated uric acid and calcium phosphate crystals can deposit in renal tubules, leading to acute kidney injury. Concurrent hyperkalaemia and hypocalcaemia can trigger life-threatening cardiac dysrhythmias, neuromuscular irritability, and seizures.

TLS is a recognised medical emergency, but it is largely preventable with foresight. Knowing if you are at risk allows your oncology team to administer protective intravenous fluids and uric-acid-lowering medications prior to treatment. Recognising symptoms early ensures that any subtle metabolic changes are corrected immediately before they cause irreversible kidney injury or serious cardiac events.

TLS is diagnosed through routine blood panels monitoring electrolytes, kidney function, and uric acid. Diagnostic biomarkers include elevated serum uric acid, potassium, phosphate, and creatinine, combined with decreased calcium, often categorised using the Cairo-Bishop diagnostic scoring system.

TLS occurs most frequently in fast-growing hematologic cancers with high cellular turnover, including acute lymphoblastic leukaemia (ALL), acute myeloid leukaemia (AML), and Burkitt lymphoma. It is less common in solid tumors unless they are exceptionally bulky and chemo-sensitive.

Management emphasizes prevention in high-risk patients through vigorous intravenous hydration and hypouricaemic agents such as allopurinol or rasburicase. If active TLS occurs, continuous cardiac monitoring, electrolyte correction, and occasionally emergency hemodialysis are necessary to support kidney function.