The relationship of histopathological characteristics of thyroid tumors with prognosis and diagnostic utility of Annexin A1 and TROP2

Introduction and Objective: Thyroid cancers constitute approximately 3.1% of all human cancers, of which 80-85% are papillary thyroid carcinoma (PTC). Although PTC has a very good prognosis, it rarely shows aggressive behavior. In our study, it is aimed to reveal the relationship between the histopathological features of PTC and prognosis and to understand the diagnostic usefulness of annexin A1 and TROP2 in thyroid tumors. Materials and Methods: Between 2005 and 2020, 2660 cases registered in Gaziantep University Medical Faculty Hospital, Department of Pathology, diagnosed with papillary thyroid carcinoma, were included in the study. The cases were divided into two groups according to the aggressive clinical course as general list and main list (n = 293). In the immunohistochemical study, 306 cases for TROP2 and 150 cases for Annexin A1, including malignant tumors and benign neoplastic and non-neoplastic cases, were selected. Results: Of the 293 cases in the main list, 98 (33.4%) were male, 195 (66.6%) were female, and the female/male ratio was 1.99. Lymph node metastasis was present in 264 cases (90%) and distant organ metastasis in 11 cases (3.7%). Disease-related death was seen in 33 cases (11%). The tumor was bilateral in 162 (55%) cases and multifocal in 149 (51%) cases. Microscopic extrathyroidal extension (ETE) was observed in 204 of the cases and macroscopic ETE was observed in 7 of the cases. A total of 173 cases had a "tall cell" variant component. In the immunohistochemical study, the sensitivity and specificity were calculated as 63.5% and 100% in PTC with TROP2, while the sensitivity was found as 83.8% and specificity as 82.8% in all thyroid malignancies with annexin A1. Conclusion: In histopathological examination of thyroid tumors; Male gender, tumor diameter >1cm, bilaterality, microscopic extrathyroidal invasion, lymph node metastasis, distant metastasis and aggressive tumor variants, mainly the "tall cell" variant, were found to be effective on prognosis and recurrence. Immunohistochemically, it was concluded that annexin A1 and TROP2 can be used for diagnostic purposes in thyroid carcinomas.