Abstract
Fine needle aspiration (FNA) is considered the gold standard in the diagnostic of thyroid nodules. Using the recommended BETHESDA reporting system, up to 20% of results are classified as intermediate cytology. As there is no consensus whether ultrasound evaluation, lobectomy or surgery is the best treatment option, intermediate cytology results are considered a grey zone of the FNA. The main aim of our study was to evaluate the performance of combined advanced ultrasound techniques in the process of diagnosis and evaluation of the intermediate cytology cases after FNA. We evaluated 54 consecutive cases with intermediate cytology on FNA, using conventional B-mode ultrasound (2B), and strain elastography, using a linear multifrequency 6–13 MHz linear probe (Hitachi Prerius Machine, Hitachi Inc, Japan). All nodules were classified with our Thyroid Imaging Report and Data System (TI-RADS) proposed model, considering: vertical appearance, with antero-posterior diameter bigger than the transvers diameter, the so called taller than wide shape, irregular borders, intranodular inhomogeneity, marked hypoecogenicity, micro calcifications, the presence of suspect lymph nodes, and increased stiffness as suspicious for malignancy. The classification outcomes were compared with the pathology results, considered the gold standard diagnosis. The prevalence of cancer was 28.8%, with 13/45 cases having a clear diagnostic of cancer. Six cases were diagnosed with borderline follicular neoplasia, a category with unclear evolution, also considered as malignant in the analysis of the imaging results. In total, 16/19 cancer cases had increased stiffness on elastography. The cancer prevalence increased with TI-RADS category, being 25% in TI-RADS 4b category and 92.8% in TI-RADS 5 category. The AUROC (Area Under Receiver Operating Curve) of elastography alone, in differentiation of malignant thyroid nodules was 74.9%; the combination of elastographic and conventional ultrasound characteristics generated an even better AUROC, of 84.5%. The combined conventional ultrasound and elastography identified thyroid cancer in cases with intermediate cytology with a sensitivity of 89.5% with a specificity of 50%. High risk thyroid nodules, identified by combined high risk conventional ultrasound characteristics and increased stiffness, on strain elastography, are highly predictive for malignancy, in the intermediate cytology cases.
Highlights
Thyroid nodules are very common in the population and most of them are benign
Fine needle aspiration (FNA) has a pivotal role in pre-surgical selection of the patients as it is the best procedure for differentiating benign from malignant nodules, and is considered the gold standard in the diagnosis of thyroid malignancy [2,3]
As follicular neoplasia “with unclear risk” is a borderline lesion that needs watchful waiting [22,23,24,25], due to uncertain risk and evolution, we considered it malignant, even if postsurgical radioactive iodine treatment was not required in all cases
Summary
Thyroid nodules are very common in the population and most of them are benign. High-resolution ultrasound (US) is the method of choice for the investigation of thyroid nodules, allowing the selection of the cases that need to be punctured [1]. Fine needle aspiration (FNA) has a pivotal role in pre-surgical selection of the patients as it is the best procedure for differentiating benign from malignant nodules, and is considered the gold standard in the diagnosis of thyroid malignancy [2,3]. The management of the patients with indeterminate cytology is a great challenge for the clinicians [6], active follow up, radical or diagnostic surgery being recommended [2,3]. The problem of this special diagnostic category is a relatively wide range of cancer risk, mean of 16%, comprised between 6–48% of cases [7,8,9]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
