Glioblastoma multiforme (GBM) is the most common primary intracranial tumor with a high lethality rate, and there is still no definitive conclusion on how to grasp the extent of surgical resection (EOR) for GBM. Yan Michael Li et al. at the University of Texas MD Anderson Cancer Center conducted a clinical study to investigate the impact of different EOR on patient survival and what clinical benefit or risk would be associated with continued resection of the abnormal signal areas surrounding the tumor on T2 FLAIR images in addition to total resection of the tumor shown on MRI-enhanced images. The findings were published online in the October 2015 issue of J Neurosurg. The study included data from 1229 patients with GBM, excluding those with multifocal tumors, EOR <78% and age >80 years. Patients were divided into two groups based on EOR: group A: EOR=100% and group B: 78%≤EOR<100%. Of these, group A was then compared in subgroups according to whether or not to proceed with resection of sufficient areas of abnormal signal around the tumor as indicated by the flair sequence (with a cut-off of 53.21% resection). Data analysis revealed that 876 patients in group A had a significantly longer median survival than 353 patients in group B, 15.2 months versus 9.8 months (p<0.001), and overall, none had a significantly increased risk of postoperative neurological dysfunction. After adjustment for prognostic factors related to age, distant quality of life score, tumor volume, tumor capsular degeneration, and preoperative symptoms, EOR was shown to have a significant effect on survival (hazard ratio=1.53, 95% CI 1.33-1.77, p<0.001). The results of subgroup analysis showed that on the basis of 100% resection of gbm shown on mri-t1 enhancement images, continued resection of more than 53.21% of peritumor signal abnormal areas shown on flair images would significantly prolong survival,20.7 months versus 15.5 months (p<0.001). The overall survival of the 477 patients who had undergone tumor resection or biopsy was not significantly different from that of untreated patients; however, multivariate regression analysis showed that patients with no history of treatment + expanded peritumor resection ≥53.21% had the longest survival, while those with a history of treatment + expanded peritumor resection <53.21% had the shortest survival (Figure 1). Figure 1. Survival curves of 643 GBM patients with expanded resection of perineural abnormal signal areas. The dashed line with black circles represents patients with no treatment history + enlarged perineural resection <53.21%; the dashed line with black squares represents patients with treatment history + enlarged perineural resection <53.21%; the solid line with black triangles represents patients with no treatment history + enlarged perineural resection ≥53.21%; and the solid line with black diamonds represents patients with treatment history + enlarged perineural resection ≥53.21%. In summary, the authors concluded that improving the surgical EOR for GBM is warranted and that continued resection of the abnormal signal area around the tumor on FLAIR sequences based on total resection of the tumor as shown on MRI-enhanced images will help prolong patient survival without increasing the risk of postoperative neurological deficits. The number of cases in this study, although large, is a single-center profile, and its conclusions have yet to be validated in a multicenter study.