MKI67 and neoplasm: To assess the prognosis of pituitary adenoma according to current WHO 2017 classification different clinical factors such as tumor size (microadenoma, macroadenoma or giant tumor), clinical presentation (clinically functioning, clinically non-functioning, or silent), invasiveness both intraoperatively and on MRI as well as histological markers like Ki-67 proliferation index, p53 expression along with the mitotic index are taken into account17,18.