O31: CORRELATION BETWEEN THYROID FINE NEEDLE ASPIRATION CYTOLOGY (FNAC) SCORES AND CANCER INCIDENCE ON FINAL HISTOPATHOLOGY – A MULTI-CENTRE RETROSPECTIVE ANALYSIS

Abstract Introduction Fine Needle Aspiration Cytology (FNAC) is the best diagnostic tool for evaluating thyroid nodules pre-operatively. The Bethesda System Reporting Thyroid Cyto-pathology (TBSRTC) in America and THY classification Europe are standardized reporting systems FNAC specimens using six categories. As compared to first edition 2009, a second of TBSRTC published 2017 has revised risk malignancy (ROM) these categories, with focus on atypia unknown significance (Thy3A) upgraded 10-30% from previously 5-15%, suspicion follicular neoplasm (Thy3F) 25-40% previous 15-30%. Method A three-year audit surgeries performed two high volume institutions January 2016 September 2019, was retrospectively. FNAs were by specialist radiologists cytopathology technician attendance rapid on-site evaluation reported as per Thy classification, Consultant Cyto-pathologist single institution. Result total 702 patients examined. There 552 who had corresponding prior surgery (mean age 53.6 years, females 79%). rates were, Thy1: 9.3%, Thy2: 4.6%, Thy3A: 10.8%, Thy3F: 28.7%, Thy4: 82.3% Thy5: 100%. main types Papillary (73.6%), Follicular (14.1%), Medullary (4%), Anaplastic (4.7%) others (3.6%). Conclusion Pre-operative diagnosis comparable criteria helped avoid misinterpretation results. Our results 2009 TBSRTC, revision. Take-home message