| Popis: |
The aim of this study was to analyze the expression of proliferative antigens (PCNA and Ki-67), c-erbB-2 oncoprotein, p53 oncoprotein and bcl-2 tumor suppressor protein in follicular adenomas and encapsulated follicular carcinomas of the thyroid gland. The study was carried out by immunohistochemistry on paraffin embedded archival material using primary antibodies purchased from DAKO. Tissue sections of 10 follicular adenomas and 10 encapsulated follicular carcinomas were analyzed. The alkaline phosphatase and horse-radish paroxidase methods were used. The majority of adenomas showed slight to moderate positivity for PCNA, Ki-67, bcl-2, and c-erbB-2 and negative staining for p53. The majority of encapsulated follicular carcinomas showed moderate positivity for PCNA, K-67 and bcl-2 and slight positivity for c-erbB-2. However, strong positive immunostaining for p53 was observed in three cases of encapsulated follicular carcinomas. Data from the literature suggest that the expression of PCNA, Ki-67, c-erbB-2, p53 and bcl-2 is related to the degree of differentiation of thyroid tumors. we observed positive immunostaining for p53 in 30% of cases of encapsulated follicular carcinomas but negative reaction in adenomas. Futhermore, it seems that at present the distinction between follicular adenomas and encapsulated follicular carcinomas should be based on histological analysis. However, it is very difficult to predict behavior of encapsulated thyroid carcinoma on the basis of morphology only. Therefore, future studies on the expression of these and additional markers should be performed. Futher investigation of a larger series of patients with a long-term follow-up is obviously needed. |
