Brenner tumours of the ovary: a study of the histology, immunohistochemistry and cellular DNA content in benign, borderline and malignant ovarian tumours.

Brenner tumours are now generally regarded as being of ovarian epithelial origin. Most have a limited growth potential and are benign. For this reason they are usually found incidentally at hysterectomy. In common with other epithelial ovarian tumours there is a histopathological spectrum of appearances ranging from benign through borderline to invasive malignancy. In this series all 54 tumours were graded according to the degree of cytological atypia, presence of mitoses and tumour necrosis. Heterogeneity of DNA content was observed in the higher grade tumours, two of the four being diploid and two being aneuploid (all benign tumours being diploid). The presence of aneuploidy correlated with the histological features and a poor clinical prognosis. Immunohistochemical staining for keratoprotein was found to be of limited value in the diagnosis of Brenner tumours and their metastases.