Serum lactate as a potential biomarker of non-glial brain tumors.

We assess whether serum lactate is a potential biomarker for non-glial cell brain tumors. Rapidly growing tumor cells typically have glycolytic rates up to 200 times higher than those of their normal tissues of origin and produce lactate even in the presence of oxygen. This phenomenon is called the Warburg effect. We recently showed that serum lactate levels can be used as a potential non-invasive biomarker in glial cell brain tumors, which correlates with both tumor grade and the extent of malignancy. In the present study, we found that patients with metastatic brain tumors had significantly higher baseline serum lactate levels compared to patients with meningioma and pituitary tumors. There was a statistically significant association between metastatic brain tumors and elevated serum lactate. We demonstrate that lactate can be used as a non-invasive biomarker to determine malignancy for brain tumors. Further analyses of larger populations will be needed to establish the value of serum lactate in determining the response to therapy or early recurrence.