A data analysis pipeline was developed to study relationships between geometric imaging features and the underlying tumor phenotype. This pipeline was run on the tumors of 203 patients clinically diagnosed with glioblastoma multiforme. For each tumor, the tumor bulk and percent non-enhancing volume was calculated, along with the surface regularity of any tumor with a 3D T1-weighted post-contrast MR scan. These features were compared to the expression of P53 and Ki67 sampled from these tumors. Although there were significant differences between multiple features for both genes, only the surface regularity was a significant predictor of Ki-67 proliferative index.