This review summarises molecular pathological techniques applicable to thyroid FNA. The molecular pathology of thyroid tumours is now fairly well understood. Molecular methods may be used as a rule-in test for diagnosis of malignancy in thyroid nodules e.g. BRAF V600E point mutation, use of a 7 gene mutational panel (BRAF V600E, RAS genes, RET/PTC or PAX8/PPARG rearrangement), or as a comprehensive multigene next-generation sequencing panel e.g. ThyroSeq v2. Molecular methods can also be applied as rule-out tests for malignancy in thyroid nodules e.g. Afirma or ThyroSeq v2 or as markers of prognosis e.g. TERT promoter mutation or other gene mutations including BRAF V600E, TP53 & AKT1 and as tests for newly defined tumour entities such as NIFTP, or as a molecular marker(s) for targeted therapies. This review describes practical examples of molecular techniques as applied to thyroid FNA in routine clinical practice.
- fine-needle aspiration