Post-menopausal ovarian fibroma associated with steroid hormone synthesis: A case report

Ovarian fibromas are benign, sex cord-stromal tumors occurring in both peri- and post-menopausal women. Generally, these tumors are non-functional and do not produce hormones. However, this case report proves the first case of steroid hormone synthesis in an ovarian fibroma by immunohistochemistry.

A 77-year-old post-menopausal woman presented with a left ovarian tumor, abnormal endometrial thickness, and high levels of estradiol (E2). The tumor was found to be a fibroma, which was positive for alpha-inhibin. We examined estrogen-producing enzymes using immunohistochemistry. The tumor was positive for estrogen receptor, progesterone receptor, 17β-hydroxysteroid dehydrogenase (HSD)-1, adrenal 4 binding protein/steroidogenic factor 1, 17β-HSD-5, steroid sulfatase, and P450c17.

This case study shows that E2 can be locally produced from circulating inactive steroids, by estrogen-producing enzymes. This is the first report of steroid hormone synthesis in an ovarian fibroma.