Dural invasion and proliferative potential of pituitary adenomas.

The relationship between invasiveness and proliferative potential was studied in 31 cases of pituitary adenomas. The invasiveness was determined by histological examination of sellar floor dura resected during transsphenoidal surgery. The proliferative potential of adenoma specimens was examined immunohistochemically using monoclonal antibody (MIB-1). There were 11 adenomas with histologically verified dural invasion out of 31 cases. These adenomas had a higher MIB-1- positive ratio than adenomas without dural invasion (p < 0.05). Pituitary adenomas with a high proliferative potential tend to be invasive.