Immunoreactive prekeratin in Brenner tumors of the ovary.

In an attempt to further characterize benign, proliferating, and malignant Brenner tumors, immunoperoxidase staining for prekeratin was undertaken in a group of these neoplasms as well as in a variety of histologically different tumors of the ovary. All Brenner tumors reacted positively for prekeratin, whereas none of the other epithelial or sex cord-stromal tumors of the ovary stained. On the basis of these findings, we conclude that prekeratin might be a useful marker for differentiating malignant Brenner tumors from histologically similar, poorly differentiated ovarian neoplasms.