National patient safety alert – harm from delayed administration of rasburicase for tumour lysis syndrome ​​(9 September 2025)

Summary

This national patient safety alert has been issued by the NHS England National Patient Safety team. It instructs all organisations providing emergency departments and cancer services to take steps to reduce the risk of harm from delayed administration of rasburicase for tumour lysis syndrome (TLS).

All actions should be completed by 9 March 2026.

Content

TLS is a life-threatening emergency that can develop when cancer cells break down rapidly, releasing harmful substances into the bloodstream. It requires urgent treatment with rasburicase in high-risk cases, ideally within 1 hour.

Patients are at risk of TLS when they have blood cancers with high tumour burden or fast-growing malignancies, particularly when starting cancer treatment that rapidly destroys cancer cells. The release of harmful cellular contents into the blood stream can overwhelm the body’s normal clearance mechanisms and lead to kidney failure, heart rhythm problems, seizures, and even death.

Rasburicase is a time-critical medication that rapidly converts uric acid released from dying cancer cells into more soluble compounds that can be safely eliminated.

The alert requires NHS organisations providing emergency departments and cancer services to implement specific improvements within 6 months, including updated risk assessment protocols, ensuring medication availability, and addressing operational barriers to timely treatment.