Tumour lysis syndrome in lymphoma: who is at risk, and rasburicase

Risk is highest in Burkitt lymphoma, in lymphoblastic lymphoma, in high-grade B-cell lymphoma and in any bulky, high-LDH aggressive lymphoma, and it rises with pre-existing renal impairment, dehydration and a raised baseline uric acid. It can also occur after venetoclax in mantle cell lymphoma and after the first dose of a bispecific antibody or CAR-T in a patient with high disease burden.

Prevention, following the British Committee for Standards in Haematology guideline: risk-stratify before the first dose; give intravenous fluids at a high rate without routine alkalinisation; give allopurinol to low- and intermediate-risk patients; give rasburicase, a recombinant urate oxidase that converts uric acid to the soluble allantoin, to high-risk patients and to anyone whose uric acid is already raised. Its United States label indicates it for the initial management of plasma uric acid in adults and children receiving anticancer therapy expected to cause tumour lysis, and limits it to a single course of treatment. Rasburicase is contraindicated in glucose-6-phosphate dehydrogenase deficiency, where it causes haemolysis and methaemoglobinaemia, so the deficiency is screened for in people from at-risk populations before it is given. Blood samples for uric acid taken after rasburicase must be transported on ice, or the enzyme continues to work in the tube and reports a falsely normal result.

Monitoring is potassium, phosphate, calcium, urate, creatinine and LDH every six to eight hours through the first cycle in high-risk patients. A pre-phase of low-dose cyclophosphamide and steroid before full-intensity chemotherapy is used in Burkitt lymphoma to shrink the tumour gradually. Renal replacement therapy is occasionally needed and is temporary in most cases.