ABSTRACT
PURPOSE: The expressions of Cytokeratin7 (CK7) and CK20 have been studied by a lot of cancer researchers, and these 2 protein markers are often used to find the primary foci of metastatic cancers. There have been numerous studies on vimentin, p53 and Ki-67 as prognostic factors for different cancers. However, it seems that there are a few investigations on the expression of CK7 and CK20 in papillary carcinoma of the thyroid. This study aimed to investigate the expressions of CK7, CK20, vimentin, p53 and Ki-67 in papillary thyroid carcinoma, and we wanted to determine whether the expressions of vimentin, p53, and Ki-67 are related to such prognostic factors as age, the tumor size, nodal metastasis or perithyroidal tissue invasion. METHODS: Paraffin slices of 44 papillary thyroid carcinomas from 44 patients were used for immunohistochemistry with using monoclonal antibody against CK7, CK20, vimentin, p53 and Ki-67. The expressions of CK7, CK20 and vimentin were determined simply by the staining competence, and more than 5% positive cells out of 1,000 cells in a highpowered microscopic view was considered as positive for the p53 and Ki-67 expressions. The expressions of vimentin, p53 and Ki-67 were investigated for their correlation with age, perithyroidal tissue invasion, the size of the tumor and metastasis to the cervical lymph nodes. RESULTS: Total of 44 patients (7 men and 37 women) were examined. The average size of tumor was 1.3 cm, and 28 (63.6%) out of 44 patients had perithyroidal tissue invasion. 29 (65.9%) patients had cervical lymph node metastases. The expression of CK7 was observed in all 44 (100%) patients, but only three (6.8%) among them had the expression of CK20. The expression of vimentin was shown in 43 (97.7%) patients. The expressions of p53 and Ki-67 were seen in 33 (75%) patients and 12 (27.7%) patients, respectively. The expressions of vimentin, p53 and Ki-67 were not significantly related with age (P=1.0, 0.084), perithyroidal tissue invasion (P=1.0, 0.798), the size of the tumor (P=0.234, 0.313) and cervical lymph node metastases (P=0.582, 0.948). CONCLUSION: As expected, papillary thyroid carcinoma showed a CK7(+)/CK20(-) pattern. Further research is needed to find the meaning of the expression of vimentin because it was meaningless analyzing the relationship between the prognostic factors due to fact that 97.7% of the patients had the expression of vimentin. There was no statistically significant relation between the expressions of p53 and Ki-67 and age, the size of thyroid tumor, perithyroidal tissue invasionand cervical lymph node metastasis.