Investigation of EZH1 expression and evaluation of the capsule status in encapsulated follicular patterned thyroid tumors and research of the utility for differential diagnosis

Tumors of the thyroid follicular pattern; follicular adenoma, follicular carcinoma, follicular and encapsulated variants of papillary carcinoma, hurthle cell adenoma, and hurhtle cell carcinoma. Diagnosis of these entities is possible with the histopathological examination. Treatment and prognosis of these lesions are different from each other. Sometimes technical reasons and differences between observers may cause difficulties in histopathological diagnosis. For this reason, there is a need for new studies that will base the distinctions of these entities on a more objective basis. In enhancer of zest, homologous 1 gene (EZH-1) acts as a subunit of the polycomb complex involved in histone H3 trimethylation and is effective in cell proliferation. With reference to these studies, EZH1 expression in thyroid tumors with follicular pattern will be investigated by both immunohistochemistry and real time PCR method, and the relationship of this expression with clinical and histopathological data will be evaluated, and according to the result, the possibilities of use in daily practice and its contribution to differential diagnosis will be investigated. Another aim of the study is to investigate the contribution of the qualitative and quantitative characteristics of the capsules of these tumors to the differential diagnosis.