Key points:

●      The definition remains the same as that set out by Cairo and Bishop, 2004. See Table 1 in original article. It is divided into the Laboratory and the Clinical (“overt”) definition of tumor lysis syndrome (TLS).

●      Every patient with a haematological malignancy commencing a new line of therapy should have a risk assessment for TLS. This should be personalised and include consideration of disease, patient and therapy factors. See Table 2 in original publication.

Prophylaxis of TLS:

●      Patients should be encouraged to drink 2–3 L fluid (children: 2–3 L/m²/day) the day before, the day of and the day after initiation of a new line of therapy. If patients are at high risk for TLS or are unable to consume the recommended amount, then they should be considered for intravenous fluid.

●      Patients with low risk of TLS: consider allopurinol for the first 7 days of the first cycle of treatment.

●      Patients with high risk of TLS: consider intravenous hydration. Consider prophylactic rasburicase (requires refrigeration), 3 mg may be sufficient but may need to be repeated depending on blood tests. Bloods should be monitored at least twice daily but may be required up to 3–4× per day depending on the clinical situation.

●      Patients with intermediate risk of TLS: Oral hydration and allopurinol may be sufficient for these patients but must be considered on a case-by-case basis, as some may warrant a strategy as per high-risk patients.

●      Prophylactic uricosuric drugs should be prescribed and administered prior to the treatment for the haematological malignancy.

●      Debulking strategies may be helpful in reducing the risk of TLS, such as prephase corticosteroids in patients with diffuse large B-cell lymphoma.

Established TLS:

●      Patients with TLS should have vigorous hydration with intravenous fluid, at an initial rate of 3 L/m²/day for adults and up to 4 L/m2/day for children, depending on renal function, clinical and fluid status. The aim is to maintain a urine output of 100 mL/m²/h in adults.

●      Treatment of electrolyte disturbances in TLS should be initiated and managed as per local guidelines and protocols. If refractory to treatment, kidney replacement therapy (KRT) should be considered. The threshold for KRT may be lower than other clinical pathologies.

●      Adult and paediatric patients with established TLS (laboratory or clinical TLS) should be treated with rasburicase 0.2 mg/kg/day for up to 7 days (although 3–5 days is frequently sufficient) with the exact duration based upon clinical response.

●      Allopurinol should be stopped when rasburicase is commenced and can be recommenced 24 h after the last dose of rasburicase.

●      In very unwell, acutely presenting patients, consideration may be made to give rasburicase without waiting for a G6PD result. This decision should be made by the consultant with overall patient responsibility and following thorough evaluation of the risks and benefits.

●      Regular clinical reassessment of the patient's fluid balance status and urine output is required to guide ongoing management. Serum potassium, uric acid, phosphate, calcium and creatinine should be measured every 6–12 h.