Comparison between glioblastoma and primary central nervous system lymphoma using MR image-based texture analysis

Purpose: To elucidate differences between glioblastoma (GBM) and primary central nervous system lym­phoma (PCNSL) with MR image-based texture features. Methods: This was an Institutional Review Board (IRB)-approved retrospective study. Consecutive, patho­logically proven, initially treated 44 patients with GBM and 16 patients with PCNSL were enrolled. We cal­culated a total of 67 image texture features on the largest contrast-enhancing lesion in each patient on post-contrast T₁-weighted images. Texture analyses included first-order features (histogram) and sec­ond-order features calculated with gray level co-occurrence matrix, gray level run length matrix (GLRLM), gray level size zone matrix, and multiple gray level size zone matrix. All texture features were measured by two neuroradiologists independently and the intraclass correlation coefficients were calculated. Reproduc­ible features with the intraclass correlation coefficients of greater than 0.7 were used for hierarchical clus­tering between the cases and the features along with unpaired t statistics-based comparisons under the control of false discovery rate (FDR) < 0.05. Principal component analysis (PCA) was performed to find the predominant features in evaluating the differences between GBM and PCNSL. Results: Twenty-one out of the 67 features satisfied the acceptable intraclass correlation coefficient and the FDR constraints. PCA suggested first-order entropy, median, GLRLM-based run length non-uniformity, and run percentage as the distinguished features. Compared with PCNSL, run percentage and median were significantly lower, and entropy and run length non-uniformity were significantly higher in GBM. Conclusions: Among MR image-based textures, first-order entropy, median, GLRLM-based run length non-uniformity, and run percentage are considered to enhance differences between GBM and PCNSL.