细胞角蛋白表达在甲状腺乳头状癌诊断中的应用

目的 探讨CK19、CK20在甲状腺乳头状癌中的表达及在诊断中的价值。方法 采用免疫组化SP法检测71例甲状腺病变中CK19、CK20蛋白的表达。结果 CK19在甲状腺乳头状癌中的阳性表达率分别为96．3％(26／27，经典型)和83．3％(5／6，滤泡变异型)，且多为强阳性表达；结节性甲状腺肿(0／23)和甲状腺腺瘤(1／15)基本不表达或仅弱阳性表达。与CK19相比，CK20在甲状腺乳头状癌中阳性率低且其阳性病例CK19也均阳性。结论 CK19阳性表达对甲状腺乳头状癌，特别是滤泡变异型具有辅助诊断作用，并对结节性甲状腺肿及甲状腺腺瘤有鉴别诊断作用。而CK20对甲状腺乳头状癌诊断价值则有限。

Expression of cytokeratins in papillary thyroid carcinoma and its diagnostic application

Objective To study the expression of cytokeratin 19 and 20 in papillary thyroid carcinomas and to evaluate its diagnostic utility. Methods Expression of cytokeratin 19 and 20 in seventy-one cases of thyroid lesions were studied by means of immunohistochemistry (SP method). Results 96.3% (26/27) and 83.3% (5/6) positive staining was observed in classic and follicular variant of papillary thyroid carcinoma, respectively. But in nodular goiters (0/23) and thyroid adenomas (1/15), no or weakly expression of cytokeratin 19 were detected. Compared with CK19 the positive rate of CK20 was lower in papillary thyroid carcinomas and CK20 positive cases also showed positive staining for CK19. Conclusions Expression of CK19 may be not only helpful in the diagnosis of papillary thyroid carcinomas, especially for the follicular variant, but also useful in the differential diagnoses with nodular goiters and thyroid adenomas. However, lower positive rate of CK20 in papillary thyoid carcinoma limits its diagnostic implication.