Prospective evaluation of clinically relevant type B hyperlactatemia in dogs with cancer.

Abstract

BACKGROUND: Cancer is considered a cause of type B hyperlactatemia in dogs. However, studies evaluating cancer as a cause of clinically relevant type B hyperlactatemia (>2.5 mmol/L) are lacking. Cancer cells have a higher lactate production because of increased aerobic glycolysis, known as the &#x201c;Warburg effect.&#x201d; The mechanisms through which aerobic glycolysis occurs are not well elucidated, but neoplasia may cause type B hyperlactatemia via this process. OBJECTIVES: To determine if malignant tumors of dogs are associated with clinically relevant type B hyperlactatemia (>2.5 mmol/L). ANIMALS: Thirty-seven client-owned dogs with malignant tumors: 22 with hematopoietic and 15 with solid tumors. METHODS: Histology was used to confirm the diagnosis (cytology was considered adequate for diagnosis of lymphoma). Confounding conditions associated with hyperlactatemia were excluded. Lactate measurements were immediately performed on free-flow jugular whole blood samples using the LactatePro analyzer. RESULTS: All dogs had lactate concentrations<2.5 mmol/L. Mean blood lactate concentration was 1.09 mmol/L. Mean blood lactate concentrations for solid and hematopoietic tumors were 0.95 and 1.19 mmol/L, respectively. Dogs with lymphoma (n=18) had a mean blood lactate concentration of 1.15 mmol/L. CONCLUSIONS: Malignant tumors were not considered a cause of clinically relevant type B hyperlactatemia. Therefore, cancer-related type B hyperlactatemia in dogs is uncommon, and hyperlactatemia should prompt careful investigation for causes other than cancer.