A potential risk factor associated with acute tumor lysis syndrome in dogs with multicentric lymphoma receiving chemotherapy.

[BACKGROUND] Acute tumor lysis syndrome (ATLS) is caused by the rapid breakdown of tumor cells, leading to electrolyte imbalances and renal dysfunction. The risk of ATLS is particularly high in lymphoma, and therefore it is crucial to consider this risk when initiating chemotherapy. However, risk factors associated with ATLS in dogs remain largely unexplored.

[HYPOTHESIS/OBJECTIVES] Identify potential risk factors for ATLS in dogs with multicentric lymphoma.

[ANIMALS] A retrospective analysis was conducted on 24 dogs diagnosed with B-cell high-grade multicentric lymphoma that received chemotherapy.

[METHODS] Blood samples were collected before treatment and on days 3, 5, and 8 after treatment. Serum concentrations of uric acid, potassium, phosphorus, calcium, and creatinine were measured based on the Cairo-Bishop Criteria to classify cases as laboratory tumor lysis syndrome (LTLS) or clinical tumor lysis syndrome (CTLS). Clinical variables, including signalment, clinical signs, comorbidities, stage, chemotherapy agents, hematologic and biochemical findings, chemotherapy response, and clinical outcomes were compared between two groups: normal and LTLS/CTLS.

[RESULTS] Of 24 dogs, LTLS occurred in 5 (20.8%), whereas CTLS occurred in 2 (8.3%). The development of LTLS/CTLS was strongly associated with the initial administration of L-asparaginase, presence of chronic kidney disease (CKD), weight loss, and metabolic acidosis. However, no significant differences were observed between the normal and LTLS/CTLS groups regarding signalment, clinical signs, stage, CBC abnormality, and clinical outcomes.

[CONCLUSIONS AND CLINICAL IMPORTANCE] Evaluating the four risk factors at the initiation of chemotherapy may help establish personalized prevention strategies for ATLS in dogs with multicentric lymphoma.