MKI67 and lymphoma: In addition, Involvement of deep regions indicates that the tumor growth invades deeper intracranial areas such as periventricular regions, basal ganglia, brainstem, and/or cerebellum [It is an important risk factor in the International Extranodal Lymphoma Study Group (IELSG) prognostic score (43), the present study similarly found that it was also an independent predictor of high Ki-67 expression levels (p < 0.05)].