MKI67 and central nervous system neoplasm: Three studies were found which investigated the association between Ki-67 expression and MR radiomics in CNS tumors: one in lower grade glioma (AUC = 0.9, accuracy = 88.6%, internal validation) [34], one in both, lower and higher-grade gliomas (AUC = 0.713, accuracy = 66%, cross-validation) [33] and one in pituitary macroadenoma (accuracy = 96.7%, internal validation) [35].