In vivo and in vitro investigations on a fast growing Brenner tumor

In vivo and in vitro investigations performed on a fast growing Brenner tumor show the following peculiarities of this tumor: 1. wide epithelial islands embedded in connective ovarian stroma, 2. rich proliferation of epithelial cells in organ cultures with the presence of mitotical figures, 3. numerical variations of chromosomes in certain metaphases. All these peculiarities reveal the tumor borderline stage.