Brenner tumor associated with rete ovarii: a histologic and immunohistochemical analysis of six cases exploring the relationship between these entities

The association of Brenner tumor (BT) with rete ovarii (RO) has been rarely alluded to in the literature. Both entities have debatable histogenesis. In this study of six cases of BT associated with RO, we describe the morphologic features and performed immunohistochemical staining for markers of Mullerian, Wolffian, mesothelial, and sex cord stromal derivation to explore the relationship between these entities. Histologically, all BTs were benign, microscopic, and incidental. RO was prominent and hyperplastic with gradual or abrupt transition to BT. In addition, focal areas of rete entrapped between BT nests were seen. All BTs were positive for GATA-3 and negative for PAX-8. Conversely, the RO in all cases was negative for GATA-3 and positive for PAX-8. WT-1 was positive in both entities. Sex cord stromal and mesothelial markers (other than WT-1) were negative in BT and RO. Although morphologically, BTs seem to arise from RO in these cases, they have a distinct immunophenotype. It is possible that at least some BTs arise from metaplastic changes in RO epithelium.

Pathology of the Fallopian Tube: Tubal Involvement by Ovarian Tumors and Incidental Findings in the Nontumoral Setting

The fallopian tube is thought to be the site of origin of most high-grade serous carcinomas (HGSCs). However, how often the tube is abnormal in the setting of other ovarian tumors is unknown. The aim of this study is to define the frequency of tubal abnormalities in the tumoral (n = 245) and nontumoral (n = 184) setting. We found that in ovarian tumors, 52.2% of the tubes were normal, while 39.2% were affected by the tumor. Abnormal tubes were found in 80% of HGSCs, in 21% of mucinous carcinomas, in 83.3% of seromucinous carcinomas, in 33.3% of endometrioid carcinomas, in 20% of clear-cell carcinomas, and in 10.5% of borderline tumors. Among normal tubes, almost 70% were histologically normal; transitional metaplasia was present in 17.4%, endometriosis in 8.1%, and adenofibroma in 2.2%, and 1.1% had an incidental serous intraepithelial tubal carcinoma. To conclude, the fallopian tube is abnormal in most serous carcinomas, and in a smaller number of endometrioid, clear-cell and mucinous carcinomas as well as borderline tumors. It is often abnormal in seromucinous tumors, but larger series are needed to study this rare subtype.