Case 61

A 65-year-old female presented with a large ovarian mass.

1. What's the diagnosis?

   A: Clear cell carcinoma

   B: HG serous carcinoma

   C: Yolk sac tumor

   D: Clear cell carcinoma with yolk sac differentiation

Answer

This case represent a clear cell carcinoma with yolk sac differentiation. The clear cell carcinoma region shows positivity for CK7, Pax-8, NapsinA, and HNF1-β, with wild-type p53 expression, and is negative for CA125, ER, PR, GPC-3, SALL4, Lin28A, and AFP, with a Ki67 proliferation index of about 30%. In contrast, the yolk sac tumor region is positive for GPC-3, SALL4, Lin28A, AFP, and HNF1-β, shows focal positivity for CA125, and maintains wild-type p53 expression while being negative for WT-1, NapsinA, ER, PR, and P16, with a high Ki67 index of approximately 90%. Case was proven to be somatic origin by STR analysis.

A paper in 1996

References: Kuwashima Y, Uehara T, Kurosumi M, Era H, Sano Y, Takahashi M, Shiromizu K, Matsuzawa M, Kishi K. Cytological distinction between clear cell carcinoma and yolk sac tumor of the ovary. Eur J Gynaecol Oncol. 1996;17(5):345-50. PMID: 8933827.

Case credit: https://qp-qp.91360.com/pc/9ad481c0394c38c2e3a2da2a55b808bc?userKey=&lang=en&cname=qpLib

Author: Wangpan Jackson Shi, MD