Yolk Sac Tumors in Postmenopausal Patients Arising in Endometrioid Adenocarcinoma

Abstract: A nulliparous, obese, diabetic 68-year-old woman with a history of pelvic endometriosis presented with an International Federation of Gynecology and Obstetrics stage III 17-cm ovarian mass. Histology showed endometriotic cysts with an intracystic growth of well-differentiated endometrioid adenocarcinoma with squamous morular change. This coexisted with a second papillary epithelial pattern corresponding to a glandular yolk sac tumor (YST) that merged with the endometrioid adenocarcinoma. Immunohistochemistry discriminated between endometrioid adenocarcinoma and glandular YST phenotypes. The expression of traditional YST markers, such as α-fetoprotein and glypican 3, was heterogeneous and irregular, failing to demarcate the YST from the endometrioid carcinoma. However, the coexpression of SALL4 and villin clearly differentiated the positive YST from the negative endometrioid adenocarcinoma. Müllerian epithelial markers, such as epithelial membrane antigen, cytokeratin 7, and PAX8, highlighted endometrioid carcinoma areas but were consistently negative in both glandular and classic variants of YST. Germ cell tumors arising from somatic Müllerian tumors in the female genital tract are aggressive, high clinical stage nondysgerminomatous tumors of both the ovary and endometrium; the most frequent association is endometrioid adenocarcinoma and YST. They likely originate from tumor stem cells. Their endometrioid adenocarcinoma component is usually high grade, although...
Source: Pathology Case Reviews - Category: Pathology Tags: Case Reviews Source Type: research