FNA Samples and FNA Procedures

The study involved 199 FNA samples of indeterminate cytology obtained from thyroid nodules in 199 consecutive patients referred for surgical excision from December 2012 to May 2016. At our institution, BRAF and H-, K-, and N-RAS mutation analysis in FNA samples is standard procedure for single thyroid nodules and/or those with suspect features on ultrasonography. Molecular analysis for somatic mutations of TERT promoter was performed retrospectively. All studies were performed in accordance with the guidelines proposed in the Declaration of Helsinki. The present study was notified to our Local Ethical Committee (Azienda Ospedaliera di Padova, code number: 42109) and all patients (including the parent/guardian on behalf of the minors) gave their written informed consent to the use of their thyroid cytology findings for research purposes. In this sample of patients, 165/199 (83%) underwent total thyroidectomy, 25/199 (13%) had a lobectomy, and 9/199 (4%) a two-step thyroidectomy.

Of the 199 cases collected, the first 88 were classified according to the SIAPEC 2007 classification, and the remainder (111 cases) according to the revised version published during the course of the study (SIAPEC 2014) (4).