Factors affecting serum lactate in patients with intracranial tumors – A report of our series and review of the literature

BACKGROUND: A hyperlactemia may occur in the presence of tissue hypoperfusion, in diseases affecting metabolism and in cases of malignant neoplasm. However, the factors affecting the serum lactate levels in patients submitted to craniotomy for the resection of an intracranial tumor have been investigated only marginally. Here, we assessed the factors possibly affecting the levels of serum lactate in intracranial tumors and carried out a thorough literature review on this topic. METHODS: All patients submitted to elective craniotomy from January 2017 to August 2018 for the resection of a glioblastoma (GBM; 101 cases) and a benign meningioma (WHO I; 105 cases) were included in this study. The sex, age, histological diagnosis, body mass index (BMI), and diabetes were assessed as possible factors affecting the level of the preoperative and postoperative serum lactate in these patients. RESULTS: We found that preoperative hyperlactemia (> 2 mmol/l) was more frequent in patients with GBM than in patients with meningioma (P = 0.0003). Moreover, a strong correlation between a preoperative lactemia and postoperative lactemia (P < 0.0001) was observed. On univariate analysis, we found increased preoperative serum lactate levels in GBM patients (P = 0.0022) and in patients with a BMI ≥30 (P = 0.0068). Postoperative serum lactate levels were significantly higher in GBM patients (P = 0.0003). On multivariate logistic regression analysis, a diagnosis of GBM was an independent factor for higher level of preoperative (P = 0.0005) and postoperative (P < 0.0001) serum lactate. CONCLUSION: The malignant phenotype of GBM is the strongest factor associated with a pre- and postoperative hyperlactemia in patients submitted to craniotomy for the resection of an intracranial tumor.