Ki-67 labeling index in glioblastoma; does it really matter?

Glioblastoma (GB) is the most common primary malignant brain tumor in adults. Ki-67 is a nonhistone nuclear protein that is expressed by cells entering the mitotic cycle and is associated with the transcription of ribosomal RNA (rRNA). In gliomas, the extent of expression of Ki-67 is roughly proportional to the histologic grade. Over the years, association studies were conducted trying to link the poor outcome in different types of malignant tumors to the Ki-67 proliferative index. This study is designed to investigate the relationship between the proliferation marker, Ki-67, and the overall survival amongst glioblastoma patients diagnosed between 2006 and 2012 at a single institution in Riyadh, Saudi Arabia.