Ovarian clear cell adenocarcinoma has a relatively poor prognosis among the ovarian cancer subtypes because of its high chemoresistance. Differential diagnosis of clear cell adenocarcinoma from other ovarian surface epithelial tumors is important for its treatment. Napsin A is a known diagnostic marker for lung adenocarcinoma, and expression of napsin A is reported in a certain portion of thyroid and renal carcinomas. However, napsin A expression in ovarian surface epithelial tumors has not previously been examined. In this study, immunohistochemical analysis revealed that in 71 of 86 ovarian clear cell adenocarcinoma patients (83%) and all of the 13 patients with ovarian clear cell adenofibroma, positive napsin A staining was evident. No expression was observed in 30 serous adenocarcinomas, 11 serous adenomas or borderline tumors, 19 endometrioid adenocarcinomas, 22 mucinous adenomas or borderline tumors, 10 mucinous adenocarcinomas, or 3 yolk sac tumors of the ovary. Furthermore, expression of napsin A was not observed in the normal surface epithelium of the ovary, epithelia of the fallopian tubes, squamous epithelium, endocervical epithelium, or the endometrium of the uterus. Therefore, we propose that napsin A is another sensitive and specific marker for distinguishing ovarian clear cell tumors (especially adenocarcinomas) from other ovarian tumors.
在所有卵巢癌中，透明细胞腺癌因其化疗耐药性而预后明显较差。透明细胞腺癌与其它卵巢上皮源性肿瘤的鉴别诊断对其治疗很重要。Napsin A 已知是肺腺癌的一个诊断标记，也表达于一部分甲状腺癌和肾癌。但是，napsin A 在卵巢上皮性肿瘤的表达不清楚。本研究表明 71/86 卵巢透明细胞腺癌患者(83%) 和全部13例卵巢透明细胞腺纤维瘤表达napsin A。30 例浆液性腺癌，11 例浆液性腺瘤或交界性肿瘤，19 例子宫内膜样腺癌， 22 例黏液性腺瘤或交界性肿瘤，10 例黏液性腺癌，3 例卵黄囊肿瘤均不表达。而且，napsin A 在卵巢正常上皮、输卵管上皮、鳞状上皮、子宫颈上皮或者子宫内膜均不表达。因此，我们推测napsin A 是将卵巢透明细胞肿瘤（尤其是腺癌）区别于其他卵巢肿瘤的又一个敏感和特异的标记物。