A Case of Virilizing Brenner Tumor in a Postmenopausal Woman With Stromal Androgenic Activity

This case report described a rare instance of a virilizing Brenner tumor in a 74-year-old postmenopausal woman, characterized by increased facial hair and elevated serum testosterone and estradiol levels. Bilateral ovarian tumors were identified and surgically removed, leading to a decrease in hormone levels. The tumors were diagnosed as benign Brenner tumors with fibrothecoma-like and luteinized stromal cells. Immunohistochemical analysis revealed that fibrothecoma-like stromal cells were positive for cytochrome P-450 aromatase, facilitating the conversion of androgen to estrogen, while luteinized stromal cells were negative for this enzyme but positive for c-Jun protein, which suppresses aromatase biosynthesis. This suggested that androgen production occurred primarily in the luteinized stromal cells due to the lack of conversion to estrogen.