This guideline has been written to assist in the management of adults and children at risk of tumour lysis syndrome (TLS) and those with established disease. The guideline clarifies the definition of TLS and assesses risk factors, taking account of the increased potency of newer agents. Prophylaxis and treatment of TLS are central to the article.

Declaration of Interests

The BSH paid the expenses incurred during the writing of this guidance. None of the authors had conflicts of interest to declare. All authors have made a declaration of interests to the BSH and Task Force Chairs which may be viewed on request.