Yolk sac tumor in postmenopausal patients: pure or associated with adenocarcinoma, a rare phenomenon.

Yolk sac tumors (YSTs) of the ovary usually present in young women and have been rarely reported in postmenopausal patients. Most of the cases in young patients are pure or associated with other germ cell components; however, in older patients there is an unusual association with Müllerian epithelial elements, for the most part malignant. We report two cases, both in older patients. One of the YSTs was associated with high-grade serous and endometrioid carcinoma, while the other case showed pure YST. The YST component showed positivity for SALL4, AFP and Glypican-3 and negative staining for PAX8 supporting a germ cell tumor differentiation; SALL4 and PAX8 markers have not been previously analyzed in this setting. Both tumors recurred within 7 months despite systemic chemotherapy.