Thyroid FNA terminology: The case for a single unified international system for thyroid FNA reporting

Abstract

The use of reporting terminologies for thyroid FNA cytology enables standardisation and international alignment of the reporting of thyroid cytology results, which is essential. There are currently three major internationally recognised systems: Bethesda (TBS), UK RCPath (Thy), and Italian (TIR). A fourth terminology system used in Japan has identical categories to TBS but with different nomenclature. The aim of this review is to discuss the strengths and weaknesses of the TBS, UK RCPath, and TIR systems, and to make the case for international terminology harmonisation and standardisation.