Ovarian yolk sac tumor in a postmenopausal woman: case report and review of the literature

Ovarian yolk sac tumor (YST) is a malignant germ cell tumor generally arising in young females and occurs very rarely after menopause. We describe a case of ovarian YST in a 60-year-old postmenopausal woman. The patient underwent total abdominal hysterectomy, bilateral salpingo-oophorectomy, and retroperitoneal lymphadenectomy for a right ovarian tumor 10 cm in diameter. Microscopic examination revealed that the tumor had the polyvesicular vitelline pattern and the glandular pattern of YST. There were no other types of germ cell tumor or any components of surface epithelial tumors, excluding ‘‘heterodifferentiation’’ of these. Immunohistochemically, tumor cells were positive for a-fetoprotein (AFP), SALL4, and only occasionally positive for cytokeratin 7, and negative for CD15 (leu-M1), and hepatocyte nuclear factor-1 beta. After surgery, the patient received 10 cycles of cisplatin-based chemotherapy. Preoperatively elevated serum AFP decreased to within the normal range after chemotherapy; however, the disease recurred and progressed rapidly, and she died of the disease 21 months after the operation. This case implies that the histogenesis of postmenopausal YST is quite different from that of a germ cell neoplasm in young females and this different histogenesis may cause the resistance to chemotherapy and poor prognosis.