Ovarian epithelial carcinoma with estrogen-producing stroma

Malignant ovarian neoplasms derived from ovarian epithelium that produce estrogen are rare among postmenopausal women. Presented herein is a case of stage Ic(a) endometrioid adenocarcinoma in the right ovary of an 81-year-old woman, who complained of mammary tenderness, pain and atypical genital bleeding. Her serum estradiol (E₂) concentration was 83 pg/mL before treatment, and the endometrial thickness measured by transvaginal ultrasonography was 5 cm, much thicker than that expected for a woman in her 80s. After surgery, her complaints disappeared and her serum E₂ level decreased to normal postmenopausal levels. Immunohistochemical studies demonstrated that the enzymes required to produce estrogen were present in the tumor. Immunohistological data indicated that this epithelial ovarian cancer could produce estradiol by itself, through potential interactions between cancer cells and stromal cells, and that the high level of estradiol in the patient's serum was caused by intratumoral production. This case indicates that in addition to stromal tumors, such as granulosa cell tumors, theca cell tumors, adenofibroma and so on, malignant epithelial tumors with a functioning stroma should also be considered when evaluating ovarian tumors with estrogen production in the elderly.