Abstract
BACKGROUND: A high serum estradiol (E2) level is occasionally detected in postmenopausal women with common epithelial ovarian tumors with functioning stroma. It has been proven that functioning stroma has the capacity to convert androgens to estrogens. However, the mechanism of the initiation and development of functioning stroma remains unclear. CASE PRESENTATION: We present two cases of elevated E2 levels in elderly women with ovarian mucinous adenocarcinomas that contained functioning stroma. Immunohistochemical evaluation revealed high expression levels of aromatase and steroidogenic factor-1 (SF-1), which is considered to be a master regulator of steroidogenesis, in their ovarian stroma. CONCLUSIONS: These cases suggest that overexpression of SF-1 may promote estrogen biosynthesis through regulation of P450 aromatase expression in ovarian tumors with functioning stroma; this in turn induces high serum E2 levels in postmenopausal women with common epithelial ovarian tumors.