OBJECTIVE: The high incidence of nodular thyroid pathology has led to growing concern about the economic impact that this pathology represents on the healthcare system. There are conclusive data about the cost-effectiveness of high-resolution units for nodular thyroid pathology; however, their implementation is not homogeneous in the Endocrinology and Nutrition services of our country. The objective of the present study was to evaluate the economic impact of the implementation of the high-resolution thyroid nodule unit (HRTNU) in our center.
METHODS: The present work is a prospective, observational and descriptive study carried out in 1314 patients (82% women, mean age 58 years ds = 11) evaluated at the HRTNU during the period of August 2022-August 2023. Demographic data (age and sex) were analyzed, referral center and consultation type, number of total consultations and neck ultrasound performed, number of fine needle aspiration (FNAB) performed, and cytology results were analyzed.
RESULTS: In the period from August 2022 to August 2023, a total of 1314 patients were evaluated (neck ultrasound and clinical consultation) and a total of 133 FNAB were performed, of which only 2.26% were non-diagnostic. Compared to the percentage of unsatisfactory FNAB from the previous year August 2021-July 2022 of 25%, a mean saving of 9931.43 euros was estimated. 84.47% of the patients evaluated for the first time by the HRTNU were discharged, estimating a mean saving of 133,200 euros.
CONCLUSIONS: The implementation of a HRTNU at the Endocrinology and Nutrition departments, coordinated with primary and specialized care, is a cost-effectiveness alternative, as it reduces the number of medical consultations and is accompanied by a higher rate of diagnostic FNAB.

OBJECTIVE: The study aimed to assess the predictive significance of inflammatory parameters as potential markers for malignancy in individuals with thyroid nodules.
METHODS: Nine hundred and ninety-one patients with thyroid nodules who had undergone thyroid fine-needle aspiration biopsy were included and classified according to the Bethesda system. Neutrophil lymphocyte ratio (NLR) and systemic immune-inflammation index (SII) values obtained from hemogram parameters were determined for each patient. The study examined the correlation between the Bethesda classification and NLR/SII levels. In addition, a comparison was made between the inflammatory parameters of the benign and malignant Bethesda groups.
RESULTS: Five hundred and seventy-three patients were classified as Bethesda 2 (benign), 34 as Bethesda 6 (malignant). A correlation was observed between the Bethesda classification and NLR and SII levels (r: 0.230, p < 0.001; r: 0.207 p < 0.001, respectively). NLR and SII values were significantly higher in the malignant group (p < 0.001). The cutoff value for SII in predicting benign and malignant thyroid nodules was 489.86 × 103/mm3 with a sensitivity of 88.2% and a specificity of 63.7%. The cutoff value for NLR for the same prediction was 2.06 with a sensitivity of 82.4% and a specificity of 83.4%.
CONCLUSIONS: The findings of this study indicate that SII and NLR may be valuable prognostic markers for predicting the malignancy of thyroid nodules.
OBJECTIVE: Evaluar parámetros inflamatorios como posibles marcadores de malignidad en individuos con nódulos tiroideos.
UNASSIGNED: Se incluyeron 991 pacientes con nódulos tiroideos que se sometieron a biopsia por aspiración con aguja fina y se clasificaron según el sistema de Bethesda. Se determinaron los valores de la relación neutrófilo-linfocito (NLR) y el índice de inflamación inmunitaria sistémica (SII). El estudio exploró la correlación entre la clasificación de Bethesda y los valores de NLR/SII, y comparó los parámetros inflamatorios de los grupos benignos y malignos de Bethesda.
RESULTS: Se clasificaron 573 pacientes como Bethesda 2 (benigno) y 34 como Bethesda 6 (maligno). Se observó una correlación entre la clasificación de Bethesda y los valores de NLR y SII (r: 0.230; r: 0.207). Los valores de NLR y SII fueron mayores en el grupo maligno (p < 0.001). El valor de corte para SII en la predicción de nódulos tiroideos benignos y malignos fue de 489.86 × 103/mm3, con una sensibilidad del 88.2% y una especificidad del 63.7%; para NLR fue de 2.06, con una sensibilidad del 82.4% y una especificidad del 83.4%.
CONCLUSIONS: El SII y el NLR pueden ser valiosos marcadores pronósticos para predecir la malignidad de los nódulos tiroideos.

OBJECTIVE: Thyroid nodules are among the most frequent conditions, with a 10% risk of malignancy. The objective is to describe the frequency of demographic, clinical, and ultrasonographic characteristics of thyroid nodule pathology in adults and to explore the relationship with tumor malignancy.
METHODS: An analytical, retrospective cross-sectional study in adults with thyroid nodules and nodular fine-needle aspiration performed in adult patients from a Colombian reference center between 2009-2019. Data were obtained from the clinical history, descriptive measures of the patient\'s demographic, clinical, and ultrasound variables were estimated, and their relationship with the malignancy of the tumor was explored.
RESULTS: A total of 445 patients and 515 nodules were included. The median age was 55 years (IQR 44-64), 86.8% of women, and 54.8% had a single lesion. Percentages of 80.2 and 19.8 were benign and malignant nodules, with a median of 15.7mm (IQR 11-25) and 12.7mm (IQR 8.5-18.3), respectively (p<0.001). Hypothyroidism and levothyroxine consumption were higher in those with malignant nodules (p<0.001). The echographic characteristics were statistically different between the nodules. In the malignant ones, there was a higher frequency of solid composition, hypoechogenicity, and irregular margins. In contrast, in the benign ones, the absence of echogenic focus stood out (p<0.001).
CONCLUSIONS: The ultrasound characteristics are essential to define the risk of malignancy of a thyroid nodule. Therefore, considering the most frequent ones can help in the most appropriate approach to primary care.

OBJECTIVE: Thyroid nodules frequently require ultrasound and Fine Needle Aspiration Cytology (FNAC) evaluation. However, FNA cytology does not allow differentiation between follicular adenoma and carcinoma on Bethesda type IV lesions. This situation leads to many unnecessary surgical procedures because it is not possible to assure the benignity of the lesions, even when most of the specimens correspond to adenomas or even other benign lesions. The objective is this study is to establish if there are any US characteristics that would help us to predict the risk of malignancy of nodules with a pathological diagnosis of follicular neoplasm in order to achieve a more conservative management for non-suspicious nodules.
METHODS: We studied 61 nodules in 61 patients (51 women and 10 men) that underwent thyroid surgery and had histopathological results of either follicular adenoma or carcinoma. Different US characteristics of the nodules were analysed (composition, echogenicity, margin, calcification status, the presence of halo and overall observer suspicion of malignancy) and were correlated with the histopathological analysis.
RESULTS: We have found a statistically significant association between the presence of calcifications, ill-defined borders and overall observer suspicion or impression (defined by well-known suspicious for malignancy ultrasonographic features, such as calcification, poorly defined margin, and a markedly hypoechoic solid nodule; and benign ultrasonographic features, such as predominantly cystic echogenic composition and the presence of a perinodular hypoechogenic halo) with follicular carcinoma. However all those features have shown low sensitivities in the present study (30%, 30% and 50%, respectively). On the other hand, the absence of halo sign has shown a sensitivity of 100% and a negative predictive value (NPV) of 100% in our study.
CONCLUSIONS: The presence of calcifications, ill-defined borders and the overall impression or suspicion of malignancy associate with a higher risk for follicular carcinoma in Bethesda type IV thyroid nodules but their absence do not allow to predict benignity in these nodules. Inversely, when a halo sign lesion is observed, benign follicular neoplasm should be considered.

BACKGROUND: Several ultrasound-based systems for classification of thyroid nodules are available. They allow for a better triage of the nodules that require cytological assessment, and lead to standardized recommendations. Our aim was to compare patients and nodules referred to fine-needle aspiration (FNA) before and after the introduction of these systems.
METHODS: A retrospective study comparing two cohorts of patients referred for FNA was performed (386 patients and 463 nodules in 2015; 220 patients and 263 nodules in 2021).
RESULTS: The sex distribution (89.1% vs 85.9% females, p=0.243), number of nodules referred to FNA per patient (median of 1), and the distribution of the Bethesda categories (p=0.082) was similar in both years. In 2021, patients were older (53.4±14.5 years vs 57.8±13.2 years, p<0.001) and nodules over one centimetre were larger (median 17.0mm vs 19.0mm, p=0.002), especially the ones categorized as Bethesda III (median size 11mm vs 23mm, p=0.043). In 2021, at least 23.1% of the nodules referred to FNA did not have any criteria, and 38.8% of the nodules were not categorized by any system.
CONCLUSIONS: This analysis draws attention to the importance of systematically applying ultrasound-based classification systems. It seems that, by not being focused mainly on size thresholds, they allow for longer surveillance periods, without aggravating the cytology results when FNA becomes indicated. Nevertheless, greater efforts are needed to ensure more standardized reports, and to increase adherence to the resulting recommendations to reduce clinical uncertainty, unnecessary FNA, and overtreatment.

Intrathyroidal thymus tissue (ITTT) is a rare, benign condition; its diagnosis can prove challenging due to unfamiliarity with this entity. However, it has ultrasonographical and cytological characteristics which can suggest its presence and thus should be considered in the differential diagnosis of thyroid nodules. Presently, immunohistochemistry can be used with fine needle aspiration (FNA) cytology, thus decreasing the need for unnecessary surgery. We discuss the usefulness of immunohistochemistry in thyroid cytology, with reference to a case of a 10-year-old patient, who underwent partial thyroidectomy for a suspicious thyroid nodule which was eventually diagnosed as ITTT by the histopathology of the surgical specimen.

Radiofrequency ablation is a well-known, safe, and effective method for treating benign thyroid nodules and recurring thyroid cancer as well as parathyroid adenomas that has yielded promising results in recent years. Since the Korean Society of Thyroid Radiology introduced the devices and the basic techniques for radiofrequency ablation in 2012, radiofrequency ablation has been approved all over the world and both the devices and techniques have improved. This review aims to instruct interventional radiologists who are doing or intend to start doing radiofrequency ablation of thyroid and parathyroid lesions, as well as thyroid and parathyroid specialists who provide pre- and post-operative care, in the training, execution, and quality control for radiofrequency ablation of thyroid nodules and parathyroid adenomas to optimize the efficacy and safety of the treatment.

OBJECTIVE: To determine the diagnostic performance of ultrasound-guided core-needle biopsy in thyroid nodules after two inconclusive fine-needle aspiration biopsies. To assess the complications of core-needle biopsy. To analyze the reliability of diagnoses obtained with core-needle biopsy. To measure the economic impact of avoiding lobectomies in patients with benign core-needle biopsy findings.
METHODS: This retrospective study reviewed 195 core-needle biopsies in 178 patients. To determine the reliability of the core-needle biopsy findings, we compared the diagnosis from the core-needle specimen versus the histologic findings in the surgical specimens when core-needle biopsy findings indicated malignancy or follicular proliferation and versus the stability of the nodule on ultrasound follow-up for one year when core-biopsy findings indicated benignity.
RESULTS: Core-needle biopsy yielded a diagnosis for 179 (91.7%) nodules, of which 122 (62.5%) were classified as benign, 50 (25.6%) as follicular proliferation, and 7 (3.6%) as malignant. The findings were inconclusive for 16 (8.3%) nodules. Minor complications were observed in 4 (2%) patients; no major complications were observed. The sensitivity of core-needle biopsy for the diagnosis of thyroid cancer was low (42.8%) because the technique was unable to detect capsular or vascular invasion, although the specificity and positive predictive value (PPV) were 100%. However, when we considered histologic findings of malignancy and follicular proliferation positive because both require surgical resection, the sensitivity increased to 97.5% and the PPV decreased to 83.3%. There were 79 nodules with ultrasound follow-up for at least one year; 76 (96.2%) had negative core-needle biopsy findings, and 74 (97.3%) of these remained stable. The negative predictive value (NPV) for malignancy of the benign nodules was 98.6%, although no malignant transformation was observed. Nevertheless, the results of the statistical analysis do not allow us to recommend forgoing ultrasound follow-up in patients with benign core-biopsy findings. The cost savings of avoiding lobectomy in patients with benign nodules and stability of the nodule on ultrasound follow-up for at least one year was about 90%.
CONCLUSIONS: Core-needle biopsy of thyroid nodules is effective because it diagnoses more than 90% of nodules with inconclusive findings after fine-needle aspiration biopsy. It is safe if done by experienced professionals. It is reliable because it yields 100% specificity and 100% PPV for malignant nodule, 97.5% sensitivity for the detection of nodules that require surgery, and 98.6% NPV for benign nodules. It is efficient because it reduces the costs of diagnosis compared to lobectomy in benign nodules.

BACKGROUND: Ultrasonography (US) is the method of choice for evaluating thyroid nodules. In 2017, the American College of Radiology (ACR) created a classification system based on US characteristics. For the system to be adopted, it must be reproducible.
OBJECTIVE: To determine the intraobserver and interobserver variability of the ACR TI-RADS.
METHODS: Cross-sectional study; three radiologists with different levels of experience used the ACR TI-RADS to classify 100 nodules on two occasions one month apart, and we calculated the intraobserver and interobserver variability.
RESULTS: Regarding intraobserver variability, the first radiologist had nearly perfect concordance for composition, echogenicity, shape, and margins and substantial concordance for echogenic foci; the second radiologist had nearly perfect concordance for composition, echogenicity, shape, and margins and substantial concordance for echogenic foci, and the third radiologist had nearly perfect concordance for composition, echogenicity, and shape and substantial concordance for margins and echogenic foci. The interobserver concordance was calculated for the two readings; the concordance was substantial except for shape in the first reading and for echogenicity and margins in the second reading, which had moderate concordance.
CONCLUSIONS: The ACR TI-RADS classification system is reproducible.

BACKGROUND: Shear-wave elastography (SWE) has been shown to be predictive of malignancy in thyroid nodules.
OBJECTIVE: To determine, by SWE, the stiffness cutoff point with the highest specificity and sensitivity to detect thyroid nodules that require surgery.
METHODS: Cross-sectional study of ultrasonographically-evaluated patients for thyroid nodules over a period of three years; the TI-RADS classification system was used, and nodule stiffness was determined by SWE. Histopathological specimens were classified using the Bethesda system, and the stiffness cutoff point with the highest specificity and sensitivity was obtained using ROC curves.
RESULTS: Forty-one percent of the nodules were classified as TI-RADS 5, and 59 %, as TI-RADS 1-4. In TI-RADS 5 nodules, median stiffness of those in Bethesda system IV-VI categories was 35.9 kPa; in nodules with TI-RADS 1-4, 21.6 kPa. In TI-RADS 5 nodules, a cutoff point > 32.5 kPa had a specificity of 75 % and sensitivity of 57 % to detect those requiring surgery; in TI-RADS 1 to 4 nodules, a cutoff point of 21.5 kPa had a specificity of 63 % and sensitivity of 51 %.
CONCLUSIONS: SWE-determined stiffness is useful to detect nodules that require surgical evaluation.
UNASSIGNED: La elastografía por ondas de corte (SWE) ha demostrado ser predictiva de malignidad en nódulos tiroideos.
UNASSIGNED: Determinar mediante SWE, el punto de corte de la rigidez con mayor especificidad y sensibilidad para detectar nódulos tiroideos que requieren cirugía.
UNASSIGNED: Estudio transversal de pacientes con nódulos tiroideos evaluados ultrasonográficamente en un periodo de tres años; se empleó la clasificación TI-RADS y mediante SWE se determinó la rigidez de los nódulos. Con el sistema Bethesda se clasificaron las muestras histopatológicas y mediante curva ROC se obtuvo el punto de corte de la rigidez con mayor especificidad y sensibilidad.
UNASSIGNED: 41 % de los nódulos fue TI-RADS 5 y 59 %, TI-RADS 1-4. En los TI-RADS 5, la mediana de rigidez de los nódulos con categoría IV-VI del sistema Bethesda fue de 35.9 kPa y en los nódulos con TI-RADS 1-4, 21.6 kPa. En los nódulos TI-RADS 5, la rigidez > 32.5 kPa tuvo especificidad de 75 % y sensibilidad de 57 % para detectar los que requieren cirugía; en los TI-RADS 1-4, el valor de corte de 21.5 kPa tuvo especificidad de 63 % y sensibilidad de 51 %.
UNASSIGNED: La rigidez determinada por SWE es útil para detectar nódulos que requerirán exploración quirúrgica.