Despite our observation that PSMA is expressed by endothelial vessels in glioblastoma, and a significant decrease at recurrence in both CD34+ vessel density and PSMA expression, there was not a significant correlation between CD34+ vessel density and PSMA expression in either primary (τb = 0.175, p = 0.143) or recurrent (τb = 0.047, p = 0.691) glioblastoma. This evidence concerns the gene CD34 and glioblastoma.