With regard to the prognostic value of Ki67 tumor cell proliferation index, only small studies or conflicting results exist for oligodendroglial tumors, diffuse astrocytomas, meningiomas and medulloblastomas [24, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44]. The gene discussed is MKI67; the disease is neoplasm.