Brenner Tumor of the Ovary: A 10-Year Single Institution Experience and Comprehensive Review of the Literature.

Brenner tumors (BTs) are surface-epithelial stromal cell tumors that are categorized by the World Health Organization as benign, borderline, and malignant. Due to the rarity of BTs, the published literature on these tumors is comprised primarily of case reports and small retrospective studies. We performed a pathology database review spanning the last ten years at our institution revealing nine reported benign BTs. We collected the clinical and pathological data of patients associated with those BTs, describing the clinical presentation and imaging results, and assessing the possible risk factors associated with them. The average age at diagnosis was 58 years. BTs were discovered incidentally in 7/9 cases. The tumor was multifocal and bilateral in 1/9 cases and ranged in size from 0.2 cm to 7.5 cm. Associated Walthard rests were found in 6/9 cases and transitional metaplasia of surface ovarian and/or tubal epithelium was found in 4/9 cases. One patient had an associated mucinous cystadenoma in the ipsilateral ovary. Another patient had an associated mucinous cystadenoma in the contralateral ovary. In conclusion, we found that Walthard rests and transitional metaplasia are common findings in association with BTs. Additionally, pathologists and surgeons need to be aware of the association between mucinous cystadenomas and BTs.