Comparable to distinct CNS and solid non-CNS malignancies, the proportion of KI-67 expressing cells has repeatedly been described as a marker of the proliferative potential in glial tumors, while fostered by its unelaborate application by immunohistochemistry in formalin-fixed, paraffin-embedded (FFPE) tissues, nowadays plays an integral role in histopathological routine diagnostics (Schröder et al. 1991; Kałuza et al. 1997; Thotakura et al. 2014). The gene discussed is MKI67; the disease is glioma.