Fra-1 Expression in Malignant and Benign Thyroid Tumor

BACKGROUND: The differential diagnosis of thyroid nodules is very important in deciding the treatment modality and the fine needle aspiration is the best diagnostic method. But, there are some limitations in use because of inadequate test materials and difficulty in interpreting. According to the study of oncogene and tumor suppressor gene about the origin of thyroid tumor, expression of Fra-1, one of AP-1 complex, is increased in thyroid neoplasm, though not present in the normal tissue. So, there is a possibility that it will be used as a method for the differential diagnosis of thyroid nodules. We tried to know whether presence or absence of Fra-1 expression can be used as a diagnostic method in differential diagnosis of thyroid nodules using the immunohistochemical (IHC) staining method. METHOD: In 4 types of thyroid tumor that were confirmed by histologic diagnosis after operation (18 cases of adenomatous goiter, 16 cases of follicular adenoma, 30 cases of papillary cancer, 10 cases of follicular cancer), IHC staining method was performed to evaluate the expression of Fra-1. RESULT: In papillary and follicular thyroid cancers, the expression of Fra-1 was stronger than in benign thyroid tumor, but there was no difference in Fra-1 expression between the two types of carcinoma. Weak expression of Fra-1 was observed in all cases of follicular adenoma, though it was weaker than in carcinoma, and it was also weakly expressed only in some cases (33%) of adenomatous goiter. CONCLUSION: The expression of Fra-1 was stronger in thyroid cancer than in benign thyroid tumor, but it was impossible to differentiate thyroid cancer from benign thyroid tumor by presence or absence of Fra-1 expression using IHC staining method.

Fra - 1 expression in malignant and benign thyroid neoplasm / 대한내과학회지

BACKGROUND: Differential diagnosis of thyroid nodule is important in deciding treatment modality and fine needle aspiration is a good method to do so. But, sometimes, it has limitation in use because of inadequate test material and difficulty in interpreting it. Among the study of oncogene and tumor suppresor gene on the origin of thyroid tumor, expression of Fra-1, one of AP-1 system, is increased in thyroid neoplasm. So there is a possibility that it would be used as a method for differential diagnosis of thyroid nodule. We tried to know whether presence or absence of Fra-1 expression can be used as a diagnostic method in differential diagnosis of thyroid nodule using immuno- histochemical(IHC) staining method. METHODS: In 4 types of thyroid tumor that was confirmed by histologic diagnosis after operation(30 cases of papillary cancer, 10 cases of follicular cancer, 16 cases of follicular adenoma, 18 cases of adenomatous goiter), IHC staining method was performed to evaluate the expression of Fra-1. RESULTS: In papillary and follicular thyroid cancer, the expression of Fra-1 was stronger than benign thyroid tumor, but there was no difference in Fra-1 expression between two types of carcinoma. Weak expression of Fra-1 was observed in all cases of follicular adenoma, and it was also weakly expressed in 6 out 18 cases of adenomatous goiter. CONCLUSION: The expression of Fra-1 was stronger in thyroid cancer than in benign thyroid adenoma, but it was impossible to differentiate thyroid cancer from benign thyroid adenoma by the presence or absence of Fra-1 expression using IHC staining method.