Diagnostic principles of thyroid tumors in pathology Relevant changes due to the current WHO classification

The current edition of the WHO classification of thyroid tumors (2017) contains a number of very relevant changes with considerable consequences for the diagnostic assessment of thyroid specimens. This applies to both the histomorphological examination of surgical specimens and the preoperative fine needle biopsy (FNB). In addition, molecular pathological examinations are becoming increasingly important in the diagnosis of thyroid tumors. Changes affect practically all areas of thyroid tumor diagnostics. Some of these changes have far-reaching consequences that justify a comprehensive commentary and query of the knowledge acquired in the form of this CME article.

Automated summary

The current edition of the WHO classification of thyroid tumors (2017) has brought about significant changes that greatly impact the diagnostic assessment of thyroid specimens, including both histomorphological examination of surgical specimens and preoperative fine needle biopsy. Additionally, molecular pathological examinations are becoming increasingly important in the diagnosis of thyroid tumors. These changes affect practically all areas of thyroid tumor diagnostics, with some changes having far-reaching consequences that warrant a comprehensive commentary and review of acquired knowledge.