| Popis: |
The incidence of papillary thyroid carcinoma is characterised with increasing tendency, with unknown reasons. Frequently the co-occurrence of papillary thyroid carcinoma and Hashimoto's thyroiditis has been observed. The aim of our study was to analyse the expression of hormone receptors, lymphocytic infiltration and thyreocyte/lymphocyte proliferation index in thyroid papillary carcinoma and in Hashimoto's thyroiditis. Study included 115 formalin-fixed and paraffin-embedded tissue material from the teaching, research and diagnostic laboratory of Tbilisi State Medical University. Study material was divided into following groups: normal thyroid gland (n=15), Non-invasive Follicular Thyroid Neoplasm with Papillary-Like Nuclear Features (NIFTP) (n=15), classic papillary carcinoma (CPC)(n=20), follicular variant of papillary carcinoma (FPC) (n=17), cylindric-cell variant of papillary carcinoma (CCPC)(n=9), Hashimoto's thyroiditis (HT) (n=25) and the co-occurrence of Hashimoto's thyroiditis and papillary carcinoma (HTPC) (n=14). Standard immunohistochemistry was used to detect ER, PR, Ki67, CK19, CD56. In addition, lymphocytic infiltration was evaluated in HE stained specimens. Study results showed that ER and PR expression is higher in FPC, CCPC and HTPC compared to CPC (p0.001), whilst lymphocytic infiltrate is lower in FPC and CCPC compared to CPC (p0.05). In addition, ER and PR expression is higher in HTPC compared to HT only (p0.001). The thyreocyte/lymphocyte proliferation index is increased in FPC and CCPC compared to CPC and it is also higher in HTPC compared to only HT and CPC (p0.05). The expression of sex steroid hormones plays an important role in the pathogenesis of papillary thyroid carcinoma. The expression level of ER and PR is even higher in cases where Hashimoto's thyroiditis and papillary carcinoma co-occur. Therefore, we can conclude that Hashimoto's thyroiditis may play an important role in the development of papillary thyroid carcinoma. |
