While nowadays amending an integral part to histopathological routine diagnostics in CNS tumors, assessment of MIB-1 LI has previously shown to contribute to differentiation of the degree of malignancy in tumors of the central nervous system, while a significant correlation to WHO grade in human glioma has been reported (Matsumoto et al. 1998; Pollack et al. 2002; Skjulsvik et al. 2014; Hsu et al. 1997; Krishnan et al. 2019). The gene discussed is MIB1; the disease is central nervous system neoplasm.