Malignant Brenner Tumor of the Ovary: A Critical Reappraisal.

Malignant Brenner tumors (MBTs) are rare epithelial tumors of the ovary, most likely arising from benign and borderline Brenner tumors. MBTs may be misdiagnosed as other primary carcinomas or nonepithelial tumors of the ovary as well as metastatic carcinomas. Accurate diagnosis usually requires clinical-radiologic correlation, extensive sampling, and immunohistochemical studies. Treatment is not standardized and may include surgery with or without chemotherapy. More than half of MBTs are diagnosed at stage I, with 47.7% and at least 20% recurrence and mortality rates, respectively. Awareness of key diagnostic features and pitfalls is essential to differentiate MBT from its mimics and ensure optimal clinical management. This comprehensive review includes classification, etiopathogenesis, historical overview, epidemiology, clinical features, treatment, prognosis, gross pathology, key morphologic features, ancillary testing, and differential diagnostic considerations for ovarian MBTs.