MKI67 and neoplasm: This study evaluated characteristics of 41 well-characterized functional corticotroph tumors consisting of 28 densely granulated corticotroph tumors (DGCTs) and 13 sparsely granulated corticotroph tumors (SGCTs) with respect to preoperative clinical and radiological findings, tumor proliferative activity (including mitotic count and Ki-67 labeling index), and postoperative early biochemical remission rates.