MKI67 and neoplasm: Likewise, Jaber et al. examined the influence of tumor volume, 18F-FET PET uptake, contrast enhancement, grade, IDH1 mutation status, O6-methylguanine DNA methyltransferase (MGMT) promoter methylation status, 1p/19q codeletion, and Ki-67/MIB-1 and proved that the intensity of fluorescence correlates with the expression of Ki-67 and with the grades of histological malignancy.