Primary juxtaovarian yolk sac tumor concurrent with an ipsilateral ovarian mature teratoma in an adult woman: a rare association

Objectives: Yolk sac tumor (YST) is a rare neoplasm that primarily occurs in the ovary in children and young women. Previously, it has been reported that the teratomatous components can be recognized in part of YSTs or appear in the contralateral ovary. Here, we report a rare case of an adult woman with a juxtaovarian YST concurrent with an ipsilateral ovarian mature teratoma. Methods: A 47-year-old woman found a pelvic mass for nine days and subsequently underwent debulking operation. The specimens were evaluated for detailed characterizations through gross examination, microscopy and immunohistochemistry. A literature review was performed and the pathogenesis was briefly discussed about the generation of an extraovarian YST concurrent with a teratoma. Results: The right juxtaovarian tumor showed typical histological patterns of YST. Immunostaining demonstrated the YST nature of Gly-3 and AFP positive tumor cells. The ipsilateral ovarian tumor was a common mature cystic teratoma with chronic fibrotic changes. According to the differences of the origin and the differentiation of the two germ cell tumors, we suspect that the occurrence of the teratoma is earlier than the YST. Conclusions: To our knowledge, this is the first report of an adult woman with a juxtaovarian YST concurrent with an ipsilateral ovarian mature teratoma.