Neutrophil-to-Lymphocyte Ratio: Can It Be Used as an Adjunct Tool to Predict Histopathological Grade of Brain Tumor?

Background Since histopathology is available only after surgery, clinical condition and radiological characters of the tumor are important factors on which a clinician counsels the patient of brain tumor to take a decision regarding the management. Neutrophil lymphocyte ratio (NLR), a marker of inflammation can be used as a prognostic marker to predict the survival in high-grade gliomas and metastases. We evaluated the utility of NLR as an adjunct tool in predicting the histopathological grade of brain tumors. Materials and Methods One hundred sixteen patients with a diagnosis of brain tumors planned for surgical excision or biopsy were enrolled in the study. NLR was estimated in the preoperative blood sample. Patients were grouped into low- and highgrade brain tumors and their mean NLRs were analyzed. Similar evaluation was carried out between the intra- and extra-axial tumors. Results Mean age of the study group was 40.14 years with 61 males. Seventy-eight patients had low-grade tumor and 38 patients had high-grade tumor. Sixty patients had extra-axial tumors and 56 patients had intra-axial tumors. The mean NLR of low-grade tumors was 1.68 ± 0.53 and that of high-grade tumors was 3.12 ± 0.74. NLR > 2.4 can be used to identify high-grade brain tumors with a sensitivity of 80%, specificity of 92%, positive predictive value of 82.1%, negative predictive value of 91%, an excellent impact with likelihood ratio (+) of 10.1, and an odds ratio of 54.1. The mean NLR of extra-axial tumors was 1.68 + 0.62 and that of intra-axial tumors was 2.64 ± 0.91. These observations were statistically significant with p -value < 0.05. Conclusions NLR is an easily available and inexpensive marker of systemic inflammation, which varies across different histopathological grades of brain tumors. Mean NLR is higher in high-grade tumors and also intra-axial tumors with a cutoff value of NLR > 2.4 and > 2.0, respectively.