Warburg's effect on solid tumors.

Lactic acidosis is the result of imbalance between the systemic formation of lactate and its hepatic metabolism. In cancer patients, lactic acidosis is mainly associated with hematologic malignancies (leukemia and lymphomas) and the mechanism is known as Warburg's effect. We report a 76-year-old male known to have hypertension and coronary artery disease, who presented with abdominal distension and lactic acidosis. His initial evaluation showed multiple liver masses that were biopsied and the patient was diagnosed with undifferentiated carcinoma of unknown primary, involving the liver. The patient had progression of lactic acidosis leading to his death on day-15. As the lactic acidosis was not in the setting of hypoxia or hemodynamic instability, we made the diagnosis of malignancy-associated type B lactic acidosis, also known as the Warburg's effect. Warburg's effect can occur in solid cancer if the tumor involves the liver. It has bad prognostic implications. The use of intravenous bicarbonate as a temporary measure is of controversial benefit, as it can potentially worsen the metabolic acidosis and its use should be limited to patients with very low pH. In cancer patients, the use of lactatebased intravenous fluids can be potentially harmful and can increase the risk of tumor metastasis, at least in animal malignancy models.