Identifying the Association of Contrast Enhancement with Vascular Endothelia Growth Factor Expression in Anaplastic Gliomas: A Volumetric Magnetic Resonance Imaging Analysis

Contrast enhancement is a crucial radiologic feature of malignant brain tumors, which are associated with genetic changes of the tumor. The purpose of the current study was to investigate the potential relationship among tumor contrast enhancement with MR imaging, vascular endothelial growth factor (VEGF) expression, and survival outcome in anaplastic gliomas. MR images from 240 patients with histologically confirmed anaplastic gliomas were retrospectively analyzed. The volumes of T2 hyperintense, contrast enhanced regions and necrotic regions on postcontrast T1-weighted images were measured. The ratio of the enhanced volume to necrotic volume was compared between patients with high versus low levels of VEGF expression and was further used in the survival analysis. The volumetric ratio of enhancement to necrosis was significantly higher in patients with low VEGF expression than in those with high VEGF expression (Mann-Whitney, p = 0.009). In addition, the enhancement/necrosis ratio was identified as a significant predictor of progression-free survival (Cox regression model, p = 0.004) and overall survival (Cox regression model, p = 0.006) in the multivariate analysis. These results suggest that the volumetric ratio of enhancement to necrosis could serve as a noninvasive radiographic marker associated with VEGF expression and that this ratio is an independent predictor for progression-free survival and overall survival in patients with anaplastic gliomas.