Which strategy best prevents tumor lysis syndrome during cancer treatment?

• A. Aggressive hydration, uric acid–lowering therapy (allopurinol or rasburicase), monitor electrolytes and uric acid, and adjust therapy as needed.
• B. Delay hydration to prevent fluid overload.
• C. Increase calcium supplementation to protect kidneys.
• D. Delay cancer therapy to prevent TLS.

Answer: (D)

Preventing tumor lysis syndrome hinges on protecting the kidneys and stabilizing electrolytes as cancer cells break down during treatment. The primary strategy is aggressive hydration to maintain good kidney perfusion and urine output, which helps clear uric acid and other cellular debris. Pairing this with uric acid–lowering therapy addresses the rush of uric acid that can crystallize in the tubules and cause renal injury. Allopurinol lowers new uric acid production, while rasburicase rapidly converts uric acid into more soluble forms, making it easier to eliminate. Ongoing monitoring of electrolytes and uric acid allows timely adjustments to therapy, such as intensifying prophylaxis or modifying treatment if risk is high, to prevent dangerous imbalances like hyperkalemia, hyperphosphatemia, and hypocalcemia.

Delaying hydration or delaying cancer therapy isn’t an effective way to prevent TLS, because the risk arises during treatment as tumor cells lyse. Simply delaying treatment doesn’t stop the cellular breakdown or its consequences. Adding calcium supplementation without addressing uric acid and electrolyte disturbances can worsen calcium-phosphate balance and doesn’t prevent TLS.