Napsin-A, a Possible Diagnostic Marker for Differentiating Clear Cell Ovarian Carcinoma From Other High-grade Ovarian Carcinomas

Abstract

Ovarian clear cell carcinoma (CCC) is divergent from other types of epithelial ovarian carcinoma in terms of clinicopathologic and molecular features. It should be separated from other high-grade carcinomas of the ovary for appropriate treatment. Napsin A is a reliable marker for adenocarcinoma of the lungs, but its role in ovarian epithelial carcinomas is vague. We investigated the expression of a panel of TTF-1, paired box 8, estrogen receptor, Wilms tumor 1, and Napsin A in 100 cases of high-grade ovarian carcinomas. All the examined cases were TTF-1 negative and paired box 8 positive. The 2 biomarkers estrogen receptor together with Wilms tumor 1 can separate CCC from endometriod carcinoma, yet this cannot be carried out in the case of serous and mucinous carcinomas of high grade. Napsin A can differentiate CCC with high sensitivity and specificity. It can be concluded that Napsin A is a sensitive and specific marker for CCC of the ovary. However, an entire marker panel may be useful for distinguishing ovarian CCC from other mimics.