Neutrophil–lymphocyte ratio dynamics are useful for distinguishing between recurrence and pseudoprogression in high-grade gliomas

OBJECTIVE: Distinguishing recurrence and pseudoprogression is a major challenge in the clinical practice of treatment for high-grade gliomas (HGGs). The neutrophil–lymphocyte ratio (NLR) has been reported to be closely related to survival in HGGs. We aimed to assess the predictive value of NLR in the differential diagnosis of recurrence and pseudoprogression. MATERIALS AND METHODS: A total of 135 patients with histologically confirmed HGGs were studied. All patients underwent focal radiotherapy and concomitant temozolomide (TMZ), followed by 6 cycles of TMZ if MRI showed no progressive enlargement of contrast-enhancing lesions. MRI evaluation was taken 4 weeks after concurrent chemoradiotherapy and then every 2 months later. NLR was calculated at 4 time points of preoperation, before concurrent RT-TMZ (pretreatment), 4 weeks following completion of RT-TMZ, and MRI showed lesion enlarged or treatment completed. RESULTS: In 135 patients, 47 (34.8%) were found to be pseudoprogression (PsPD), and 28 (20.7%) were early disease progression (ePD). The mean pretreatment and post-treatment NLR were 4.2±2.1 and 5.1±3.5, respectively. The median overall survival in the PsPD group (25.2 months) was significantly longer than in the ePD (15.4 months) and no progression group (nPD) (21.6 months) (p<0.001). Overall survival was significantly shorter in the baseline NLR≥4 cohort compared with NLR<4 (p=0.03), but no significant difference was found between PsPD and ePD (p=0.197). Patients with decreased NLR showed significantly longer survival than no decreased group (p<0.001), and decreased NLR was found to be a significant difference between PsPD and ePD (p=0.022). Univariate and multivariate logistic regression analyses suggested that decreased NLR was an independent prognosis factor (p=0.031). CONCLUSION: Decreased NLR is an independent prognostic factor and is useful for distinguishing between recurrence and pseudoprogression in HGGs.