A nomogram based on ultrasound radiomics for predicting the invasiveness of cN0 single papillary thyroid microcarcinoma.

Background: Up to 15.3% of papillary thyroid microcarcinoma (PTMC) patients with negative clinical lymph node metastasis (cN0) were confirmed to have pathological lymph node metastasis in level VI. Conventional ultrasound (US) focuses on the characteristics of tumor capsule and the periphery to determine whether the tumor has invasive growth. However, due to its small size, the typical features of invasiveness shown by conventional 2-dimensional (2D) US are not well visualized. US-based radiomics makes use of artificial intelligence and big data to build a model that can help improving diagnostic accuracy and providing prognostic implication of the disease. We hope to establish and assess the value of a nomogram based on US radiomics combined with independent risk factors in predicting the invasiveness of a single PTMC without clinical lymph node metastasis (cN0). Methods: A total of 317 patients with cN0 single PTMC who underwent US examination and operation were included in this retrospective cohort study. Patients were randomly divided into training and testing set in the ratio of 8:2. The US images of all patients were segmented, and the radiomics features were extracted. In the training dataset, the US with features of minimum redundancy maximum relevance (mRMR) and the least absolute shrinkage and selection operator (LASSO) were selected and radiomics signatures were then established according to their respective weighting coefficients. Univariate and multivariate logistic regression analyses were employed to generate the risk factors of possible invasive PTMC. The nomogram is then made by combining high risk factors and the radiomics signature. The efficiency of the nomogram was evaluated by the receiver operating characteristic (ROC) curve and calibration curve, and its clinical application value was assessed by decision curve analysis (DCA). The testing dataset was used to validate the model. Results: In the model, seven radiomics features were selected to establish the radiomics signature. A nomogram was made by incorporating clinically independent risk factors and the radiomics signature. Both the ROC curve and calibration curve showed good prediction efficiency. The area under the curve (AUC), accuracy, sensitivity, and specificity of the nomogram in the training data were 0.76 [95% confidence interval (CI): 0.71-0.82], 0.811, 0.914, and 0.727, respectively whereas the results of the testing dataset were 0.71 (95% CI: 0.58-0.84), 0.841, 0.533, and 0.868. As such, the efficacy of the nomogram in predicting the invasiveness of PTMC was subsequently validated by the DCA. Conclusions: Nomogram based on thyroid US radiomics has an excellent predictive value of the potential invasiveness of a single PTMC without clinical lymph node metastasis. With these promising results, it can potentially be the imaging marker used in daily clinical practice.

Análisis de características clínicas y ecográficas de nódulos tiroideos con citología Bethesda III y su evolución / Analysis of Clinical and Ultrasound Features of Thyroid Nodules With Bethesda III Cytology and their Evolution

Introducción: Desde la implementación de la clasificación citológica de los nódulos tiroideos por el sistema Bethesda en 6 categorías, el grupo Bethesda III (BIII) es el que genera más controversias en cuanto a la conducta de seguimiento. Según la literatura corresponden a esta categoría entre el 4 y 20 % de los nódulos punzados y conllevan un riesgo de malignidad del 5-15 %. Objetivo: Determinar características clínicas y ecográficas de los nódulos tiroideos clasificados como BIII en nuestra población y analizar su evolución en el tiempo. Materiales y Métodos: Estudio descriptivo de todos los pacientes enviados a PAAF bajo guía ecográfica que resultaron BIII, entre febrero 2011 y diciembre 2013. Se describieron las características clínicas y ecográficas de dichos nódulos y su evolución. La mediana de seguimiento fue 24 meses (rango: 2 a 35 meses). Resultados: Fueron punzados 945 nódulos de 784 pacientes. Se clasificaron como BIII 85 nódulos (8,99 %) de 72 pacientes (69 mujeres y 3 varones), con una media de edad de 71,1 ±7,1 años. La mediana del diáme­tro mayor de los nódulos fue 18 mm (9 a 54 mm). El 76,1 % de los nódulos fueron sólidos, el 22,5 % mixtos y en 1 caso espongiforme. Según el patrón ecográfico: 36,7 % eran hipoecoicos, 54,4 % isoecoicos y 8,9 % hiperecoicos. El 8,33 % presentó microcalcificaciones y el 9,9 % márgenes irregulares. El 39,43 % presentó vascularización periférica, 4,23 % central y 56,34 % mixta. Evolución: De los 72 pacientes, 9 (12,1 %) se perdieron en el seguimiento, a 56 (77,8 %) se los siguió clínica y ecográficamente, y en 7 pacientes (9,7 %) se tomó conducta quirúrgica basándose en criterios clínicos y ecográficos sospechosos de malignidad, o por antecedentes familiares positivos, resultando 3 con carcinoma papilar (CP), y 4 con patología benigna. Durante el seguimiento, Fueron repunzados 40 nódulos de 35 pacientes (48,6 %) que resultaron: 2 BI, 23 BII, 14 BIII y 1 BV. De los 14 nódulos con segunda punción BIII, se operaron 7, 1 CP y 6 patología benigna. El nódulo BV resultó un CP a su cirugía. En total, fueron operados 16 pacientes con BIII (22,2 %) (7 de inicio y 8 luego de la segunda PAAF y 1 en el seguimiento clínico ecográfico), de los cuales 5 (31,25 %) resultaron CP y 11 (68,75 %) patología tiroidea benigna. Conclusión: Si bien para los nódulos tiroideos con categoría BIII se recomienda generalmente una repunción, en nuestra experiencia el hallazgo de características clínicas y ecográficas sospechosas de malignidad y/o antecedentes familiares de cáncer de tiroides permitiría en algunos pacientes optar por la cirugía tiroidea desde el inicio. Rev Argent Endocrinol Metab 52:14-21, 2015 Los autores declaran no poseer conflictos de interés.

Background: Since the implementation of the Bethesda System for cytology classification of thyroid nodules into 6 categories, the Bethesda III group (B III) has been the most controversial as regards follow-up management. Reported data shows that about 4 to 20 % of all biopsied nodules belong to this category, with the risk of malignancy being 5 to 15 %. Objective: To determine clinical and sonographic features of thyroid nodules classified as BIII in our population and analyze their evolution over time. Methods: We determined the clinical and ultrasonographic (US) features of all patients who had undergone fine needle aspiration biopsy (FNAB) in 2011-2013 at our Institution for Retirees and Pensioners. Descriptive study of all patients with nodules classified as BIII with a median follow-up time of 24 months (2 to 35 months). Results: Out of 945 nodules from 784 patients biopsied (age, mean ± SD:71.1±7.1 years), 85 (8.99 %) were classified as BIII. Six patients had received neck radiation, and 5 reported family history of thyroid cancer. The median (range) largest diameter of nodules was 18 mm (9-54 mm). Fifty-four nodules (76.1 %) were solid, 16 (22.5 %) mixed, and 1 spongiform. Based on echogenicity, 36.7 % were hypoechoic, 54.4 % isoechoic and 8.9 % hyperechoic. Twenty-two nodules (25.88 %) were taller than wider, 8.33 % had microcalcifications and 9.9 % had irregular margins. At Doppler evaluation, 39.43 % of nodules had peripheral vascularity, 4.23 % showed central vascularity and 56.34 % had mixed vascularity. In 7 out of 72 patients with BIII classification, surgery was indicated at the start based on suspicious clinical and US findings for malignancy, or family history of thyroid cancer. Out of these 7 patients, 3 were found to have papillary carcinoma (PTC), 1 follicular adenoma (FA), 1 colloid goiter (CG), 1 adenomatous nodule (AN) and 1 chronic lymphocytic thyroiditis (CLT). As regards the follow-up and evolution of the rest of the group, 9 were lost, 21 remained in observation and 35 (48.6 %) with 40 nodules underwent a second FNAB, with the following results: 2 BI, 23 BII, 14 BIII and 1 BV. Out of 14 nodules confirmed as BIII on repeat FNAB, 7 were operated on, resulting in: 2 CLT, 3 CG, 1 FA and 1 PTC. The BV nodule proved to be PTC. A total of 16 patients with BIII nodules underwent surgery (7 initially, 8 after a second FNAB, and 1 during clinical and US follow-up) and 5 (31.25 %) were PTC while 11 (68.75 %) were benign. Conclusion: Even though BIII thyroid nodules generally require a second FNAB, in our experience clinical and US findings suspicious for malignancy, or family history of thyroid cancer could allow some patients to be offered surgery at initial presentation. Rev Argent Endocrinol Metab 52:14-21, 2015 No financial conflicts of interest exist.

Análisis de características clínicas y ecográficas de nódulos tiroideos con citología Bethesda III y su evolución / Analysis of Clinical and Ultrasound Features of Thyroid Nodules With Bethesda III Cytology and their Evolution

Introducción: Desde la implementación de la clasificación citológica de los nódulos tiroideos por el sistema Bethesda en 6 categorías, el grupo Bethesda III (BIII) es el que genera más controversias en cuanto a la conducta de seguimiento. Según la literatura corresponden a esta categoría entre el 4 y 20 % de los nódulos punzados y conllevan un riesgo de malignidad del 5-15 %. Objetivo: Determinar características clínicas y ecográficas de los nódulos tiroideos clasificados como BIII en nuestra población y analizar su evolución en el tiempo. Materiales y Métodos: Estudio descriptivo de todos los pacientes enviados a PAAF bajo guía ecográfica que resultaron BIII, entre febrero 2011 y diciembre 2013. Se describieron las características clínicas y ecográficas de dichos nódulos y su evolución. La mediana de seguimiento fue 24 meses (rango: 2 a 35 meses). Resultados: Fueron punzados 945 nódulos de 784 pacientes. Se clasificaron como BIII 85 nódulos (8,99 %) de 72 pacientes (69 mujeres y 3 varones), con una media de edad de 71,1 ±7,1 años. La mediana del diáme¡tro mayor de los nódulos fue 18 mm (9 a 54 mm). El 76,1 % de los nódulos fueron sólidos, el 22,5 % mixtos y en 1 caso espongiforme. Según el patrón ecográfico: 36,7 % eran hipoecoicos, 54,4 % isoecoicos y 8,9 % hiperecoicos. El 8,33 % presentó microcalcificaciones y el 9,9 % márgenes irregulares. El 39,43 % presentó vascularización periférica, 4,23 % central y 56,34 % mixta. Evolución: De los 72 pacientes, 9 (12,1 %) se perdieron en el seguimiento, a 56 (77,8 %) se los siguió clínica y ecográficamente, y en 7 pacientes (9,7 %) se tomó conducta quirúrgica basándose en criterios clínicos y ecográficos sospechosos de malignidad, o por antecedentes familiares positivos, resultando 3 con carcinoma papilar (CP), y 4 con patología benigna. Durante el seguimiento, Fueron repunzados 40 nódulos de 35 pacientes (48,6 %) que resultaron: 2 BI, 23 BII, 14 BIII y 1 BV. De los 14 nódulos con segunda punción BIII, se operaron 7, 1 CP y 6 patología benigna. El nódulo BV resultó un CP a su cirugía. En total, fueron operados 16 pacientes con BIII (22,2 %) (7 de inicio y 8 luego de la segunda PAAF y 1 en el seguimiento clínico ecográfico), de los cuales 5 (31,25 %) resultaron CP y 11 (68,75 %) patología tiroidea benigna. Conclusión: Si bien para los nódulos tiroideos con categoría BIII se recomienda generalmente una repunción, en nuestra experiencia el hallazgo de características clínicas y ecográficas sospechosas de malignidad y/o antecedentes familiares de cáncer de tiroides permitiría en algunos pacientes optar por la cirugía tiroidea desde el inicio. Rev Argent Endocrinol Metab 52:14-21, 2015 Los autores declaran no poseer conflictos de interés.(AU)

Background: Since the implementation of the Bethesda System for cytology classification of thyroid nodules into 6 categories, the Bethesda III group (B III) has been the most controversial as regards follow-up management. Reported data shows that about 4 to 20 % of all biopsied nodules belong to this category, with the risk of malignancy being 5 to 15 %. Objective: To determine clinical and sonographic features of thyroid nodules classified as BIII in our population and analyze their evolution over time. Methods: We determined the clinical and ultrasonographic (US) features of all patients who had undergone fine needle aspiration biopsy (FNAB) in 2011-2013 at our Institution for Retirees and Pensioners. Descriptive study of all patients with nodules classified as BIII with a median follow-up time of 24 months (2 to 35 months). Results: Out of 945 nodules from 784 patients biopsied (age, mean ± SD:71.1±7.1 years), 85 (8.99 %) were classified as BIII. Six patients had received neck radiation, and 5 reported family history of thyroid cancer. The median (range) largest diameter of nodules was 18 mm (9-54 mm). Fifty-four nodules (76.1 %) were solid, 16 (22.5 %) mixed, and 1 spongiform. Based on echogenicity, 36.7 % were hypoechoic, 54.4 % isoechoic and 8.9 % hyperechoic. Twenty-two nodules (25.88 %) were taller than wider, 8.33 % had microcalcifications and 9.9 % had irregular margins. At Doppler evaluation, 39.43 % of nodules had peripheral vascularity, 4.23 % showed central vascularity and 56.34 % had mixed vascularity. In 7 out of 72 patients with BIII classification, surgery was indicated at the start based on suspicious clinical and US findings for malignancy, or family history of thyroid cancer. Out of these 7 patients, 3 were found to have papillary carcinoma (PTC), 1 follicular adenoma (FA), 1 colloid goiter (CG), 1 adenomatous nodule (AN) and 1 chronic lymphocytic thyroiditis (CLT). As regards the follow-up and evolution of the rest of the group, 9 were lost, 21 remained in observation and 35 (48.6 %) with 40 nodules underwent a second FNAB, with the following results: 2 BI, 23 BII, 14 BIII and 1 BV. Out of 14 nodules confirmed as BIII on repeat FNAB, 7 were operated on, resulting in: 2 CLT, 3 CG, 1 FA and 1 PTC. The BV nodule proved to be PTC. A total of 16 patients with BIII nodules underwent surgery (7 initially, 8 after a second FNAB, and 1 during clinical and US follow-up) and 5 (31.25 %) were PTC while 11 (68.75 %) were benign. Conclusion: Even though BIII thyroid nodules generally require a second FNAB, in our experience clinical and US findings suspicious for malignancy, or family history of thyroid cancer could allow some patients to be offered surgery at initial presentation. Rev Argent Endocrinol Metab 52:14-21, 2015 No financial conflicts of interest exist.(AU)

Radiofrequency ablation of benign thyroid nodules and recurrent thyroid cancers: consensus statement and recommendations.

Thermal ablation using radiofrequency is a new, minimally invasive modality employed as an alternative to surgery in patients with benign thyroid nodules and recurrent thyroid cancers. The Task Force Committee of the Korean Society of Thyroid Radiology has developed recommendations for the optimal use of radiofrequency ablation for thyroid nodules. These recommendations are based on a comprehensive analysis of the current literature, the results of multicenter studies, and expert consensus.

Radiofrequency Ablation of Benign Thyroid Nodules and Recurrent Thyroid Cancers: Consensus Statement and Recommendations

Thermal ablation using radiofrequency is a new, minimally invasive modality employed as an alternative to surgery in patients with benign thyroid nodules and recurrent thyroid cancers. The Task Force Committee of the Korean Society of Thyroid Radiology has developed recommendations for the optimal use of radiofrequency ablation for thyroid nodules. These recommendations are based on a comprehensive analysis of the current literature, the results of multicenter studies, and expert consensus.

Ultrasonography and the ultrasound-based management of thyroid nodules: consensus statement and recommendations.

The detection of thyroid nodules has become more common with the widespread use of ultrasonography (US). US is the mainstay for detecting and making the differential diagnosis of thyroid nodules as well as for providing guidance for a biopsy. The Task Force on Thyroid Nodules of the Korean Society of Thyroid Radiology has developed recommendations for the US diagnosis and US-based management of thyroid nodules. The review and recommendations in this report have been based on a comprehensive analysis of the current literature, the results of multicenter studies and from the consensus of experts.

Ultrasonography and the Ultrasound-Based Management of Thyroid Nodules: Consensus Statement and Recommendations

The detection of thyroid nodules has become more common with the widespread use of ultrasonography (US). US is the mainstay for detecting and making the differential diagnosis of thyroid nodules as well as for providing guidance for a biopsy. The Task Force on Thyroid Nodules of the Korean Society of Thyroid Radiology has developed recommendations for the US diagnosis and US-based management of thyroid nodules. The review and recommendations in this report have been based on a comprehensive analysis of the current literature, the results of multicenter studies and from the consensus of experts.

Ultrasound-Guided Fine-Needle Aspiration Biopsy in Infracentimetric Thyroid Nodules

PURPOSE: The aim of this study is to determine the efficacy of ultrasound-guided fine-needle aspiration biopsy (US-FNAB) of thyroid nodules that are equal to or less than 1 cm at the maximum diameter. MATERIALS AND METHODS: The US-FNABs performed on thyroid nodules from March to August 2009 were included in this study. We retrospectively evaluated the cytopathologic results as well as any complications associated with the procedure. RESULTS: Of the 241 thyroid nodules (range: 0.1 - 1.0 cm, mean size: 5.8 mm) in 184 patients (female: male = 164:20, mean age: 49.0 years, age range: 18 - 77 years old), the incidence of an inadequate sample was 14.1% (34/241) for the US-FNABs. Eighty six nodules were surgically removed in 62 patients, of which 15 were confirmed to be benign nodules and 71 were confirmed to be malignant nodules. The number of true positive, false positive, true negative and false negative results for US-FNAB were 59, 0, 10 and 3%, respectively, and the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 95.2%, 100%, 100%, 76.9% and 95.8%, respectively. All the false negative cases were less than 3 mm at the maximal diameter. There were no serious complications in all the patients. CONCLUSION: US-FNAB was effective for the cases of thyroid nodule under 1 cm at the maximal diameter. However, a false negative result of US-FNAB should be considered for the cases of very small nodules that are less than 3 mm at the maximal diameter.

Ultrasonographic findings of medullary thyroid carcinoma: a comparison with papillary thyroid carcinoma.

OBJECTIVE: This study was designed to evaluate the ultrasonographic (US) findings of medullary thyroid carcinoma (MTC) as compared to findings for papillary thyroid carcinoma (PTC). MATERIALS AND METHODS: The study included 21 cases of MTC that were surgically diagnosed between 2002 and 2007 and 114 cases of PTC that were diagnosed in 2007. Two radiologists reached a consensus in the evaluation of the US findings. The US findings were classified as recommended by the Thyroid Study Group of the Korean Society of Neuroradiology and Head and Neck Radiology (KSNHNR) and each nodule was identified as suspicious malignant, indeterminate or probably benign. The findings of medullary and papillary carcinomas were compared with use of the chi-squared test. RESULTS: The common US findings for MTCs were solid internal content (91%), an ovoid to round shape (57%), marked hypoechogenicity (52%) and calcifications (52%). Among the 21 cases of MTC nodules, 17 (81%) were classified as suspicious malignant nodules. The mean size (longest diameter) of MTC nodules was 19 +/- 13.9 mm and the mean size (longest diameter) of PTC nodules was 11 +/- 7.4 mm; this difference was statistically significant (p < 0.05). An ovoid to round shape was more prevalent for MTC lesions than for PTC lesions (p < 0.05). CONCLUSION: The US criteria for suspicious malignant nodules as recommended by the Thyroid Study Group of the KSNHNR correspond to most MTC cases. The US findings for MTC are not greatly different from PTC except for the prevalence of an ovoid to round shape.

A 7-year follow-up of patients with thyroid cysts and pseudocysts treated with percutaneous ethanol injection: volume change and cost analysis.

Thyroid cysts and pseudocysts, or hemorrhagic cysts, are quite frequent thyroid pathologies. Surgical theraphy has always been the treatment of choice in this pathology, but percutaneous ethanol injection (PEI) is becoming still more common. PEI was originally used in the treatment of liver nodules and subsequently in solid, hyperfunctioning thyroid nodules, but today it is used exclusively in cysts. The aim of this study was to evaluate the efficacy of PEI in reducing thyroid cyst volume 12 and 84 months after treatment and to compare cost-benefit to that of surgical treatment. The study includes 110 consecutive patients, who all underwent PEI after cytological analysis had excluded the presence of neoplasia. All patients had refused surgical treatment. One patient died during the follow-up due to cerebral hemorrhage. Each patient received an average of 5.3 ± 2.7 PEI treatments. After 12 months, volume was reduced by 82.6% and after 84 months by 93.03%. Dysphonia occurred in 2 cases of which one resolved spontaneously and one received cortisone therapy. The cost of PEI treatment is considerably lower than the cost of surgical therapy (the cost saving in our patient population was about €200,000). PEI should therefore be preferred to surgical treatment due to its efficacy and lower cost.

Calcified Thyroid Nodules: Review of the Significance of Peripheral Calcifications

Thyroid calcification may occur in both benign and malignant thyroid disease, but previous literature reports have indicated that calcification is more common in malignant lesions than it is in benign ones. Various patterns of calcification are seen, including microcalcification, coarse dense macrocalcification, and peripheral calcification. Microcalcification and coarse dense macrocalcification are two of the most specific features of thyroid malignancy. However, to date, the clinical significance of peripheral calcification remains unclear and therefore controversial. In this pictorial review, we describe the ultrasonographic features of calcified thyroid nodules and seek to delineate the spectrum and determine the clinical significance of peripheral calcification by correlating it with pathologic results. A broad spectrum of benign to malignant tumors is associated with peripheral calcification. Peripheral calcification in a thyroid nodule should be considered to indicate an indeterminate lesion, and ultrasonography-guided FNAB or core biopsy should be performed in order to exclude malignancy.

Ultrasonographic Findings of Medullary Thyroid Carcinoma: a Comparison with Papillary Thyroid Carcinoma

OBJECTIVE: This study was designed to evaluate the ultrasonographic (US) findings of medullary thyroid carcinoma (MTC) as compared to findings for papillary thyroid carcinoma (PTC). MATERIALS AND METHODS: The study included 21 cases of MTC that were surgically diagnosed between 2002 and 2007 and 114 cases of PTC that were diagnosed in 2007. Two radiologists reached a consensus in the evaluation of the US findings. The US findings were classified as recommended by the Thyroid Study Group of the Korean Society of Neuroradiology and Head and Neck Radiology (KSNHNR) and each nodule was identified as suspicious malignant, indeterminate or probably benign. The findings of medullary and papillary carcinomas were compared with use of the chi-squared test. RESULTS: The common US findings for MTCs were solid internal content (91%), an ovoid to round shape (57%), marked hypoechogenicity (52%) and calcifications (52%). Among the 21 cases of MTC nodules, 17 (81%) were classified as suspicious malignant nodules. The mean size (longest diameter) of MTC nodules was 19 +/- 13.9 mm and the mean size (longest diameter) of PTC nodules was 11 +/- 7.4 mm; this difference was statistically significant (p < 0.05). An ovoid to round shape was more prevalent for MTC lesions than for PTC lesions (p < 0.05). CONCLUSION: The US criteria for suspicious malignant nodules as recommended by the Thyroid Study Group of the KSNHNR correspond to most MTC cases. The US findings for MTC are not greatly different from PTC except for the prevalence of an ovoid to round shape.

Ultrasound-guided Fine-needle Aspiration Biopsy of Thyroid Nodules: Comparison of the Pain Scale according to the Application of Local Anesthesia

PURPOSE: This study was designed to evaluate the difference in the degree of patient pain during an ultrasoundguided fine-needle aspiration biopsy (US-FNAB) with the use of a one-needle puncture for thyroid nodules with the application of local anesthesia. MATERIALS AND METHODS: We prospectively examined patients who simultaneously received US-FNAB for two thyroid nodules, for one nodule in the right lobe and one nodule in the left lobe, where the nodules were larger than 10 mm in the maximum diameter. US-FNAB with or without local anesthesia was performed with the use of a 23-guage needle in all patients. The degree of pain after performing US-FNAB was evaluated by the use of an 11-point numeric rating scale. RESULTS: For all 20 patients, US-FNAB was performed with an alternative selection of the nodules. There were 14 patients with a higher pain score where local anesthesia was administered, two patients with a higher pain score where local anesthesia was not administered and four patients with the same score where both methods were used. There was a statistically significant difference in the pain score between the use of the two methods (Wilcoxon sign rank test, p = 0.014). The mean value of the pain score was 3.1 in patients who received local anesthesia and 2.1 in patients that did not receive local anesthesia, respectively. CONCLUSION: The use of local anesthesia is not superior to the use of no anesthesia regarding pain relief if USFNAB is performed with a one-needle puncture.

Analysis of the Malignancy Rate for Thyroid Nodules based on the Use of a Fine Needle Aspiration Biopsy and Ultrasonography

PURPOSE: This study was designed to analyze the malignancy rate for thyroid nodules determined after a fine needle aspiration biopsy (FNAB) and ultrasonography (US) and to propose follow-up FNAB indications. MATERIALS AND METHODS: A total of 287 patients (265 female, 22 male) who underwent repeated US-guided FNABs were included in the cohort study. The results of the FNABs were classified as inadequate, benign, indeterminate, suspicious for a malignancy and a malignancy. The US findings were assigned five grades according to the possibility of a malignancy present. The frequency of a malignant nodule was evaluated by the use of the Kaplan-Meier method and Cox proportional risk model. RESULTS: The malignancy rates of inadequate, benign, and indeterminate nodules were 12.8%, 8.2% and 37.5%, respectively, for the FNAB findings. The rates of grades 3, 4 and 5 were 38.6%, 50.0% and 53.8%, respectively, for the US findings. Inadequate and indeterminate nodules as determined by an FNAB and grades 3, 4 and 5 assigned after US showed a higher malignancy rate than other nodules and would be regarded as high risk lesions. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 93.3%, 38.4%, 22.0%, 96.9% and 47.0%, respectively, if the nodule was considered a high-risk lesion, based on the FNAB or US findings. CONCLUSION: Thyroid nodules should be evaluated based on an FNAB and US findings. If a thyroid nodule is classified as a high-risk lesion, a follow-up study is needed due to the high malignancy rate.

Killian-Jamieson Diverticulum Mimicking a Thyroid Nodule on Ultrasonography: A Case Report

Thyroid ultrasonography is widely used for diagnosis and cytologic evaluation of thyroid nodules. We encountered a case of Killian-Jamieson diverticulum, which was differentiated from a thyroid nodule using ultrasonography.

Feasibility of an Ultrasonographic Categorical Reporting System for Thyroid Incidentaloma

PURPOSE: To evaluate the feasibility of an ultrasonographic category system for the proper management of incidentally found thyroid nodules. MATERIALS and METHODS: We retrospectively evaluated 2,688 patients who had thyroid nodules and underwent ultrasonography-guided fine needle aspiration biopsy. We made an ultrasonographic categorical reporting system by logistic regression analysis for comparison with the pathologic results of cytology and biopsy. RESULTS: The distribution of malignancy probability for benign nodules was 0.07 to 0.23 and for malignant nodules was 0.37 to 0.91 (95% confidence intervals). We stratified the distribution of the probability of malignancy of each nodule into 6 categories (category 0, no nodule; 1, highly suggestive of benignancy; 2, probably benign; 3, indeterminate; 4, probably malignant; and 5, highly suggestive of malignancy) and summarized the representative US findings. We compared the category of each nodule with the pathological results. In nodules with surgically proven pathologic diagnoses, benign lesions were 96.1% (348/361) in category 1 and malignant lesions were 98.6% (139/141) in category 5. CONCLUSION: We suggest that the ultrasonographic category system for thyroid incidentaloma may provide optimal strategies to manage incidentally found thyroid nodules.

Sonographic Findings of Hashimoto's Thyroiditis and Associated Nodular Lesions

PURPOSE: To evaluate the sonographic findings of Hashimoto's thyroiditis and associated nodular lesions. MATERIALS and METHODS: We retrospectively reviewed the sonographic findings of twenty patients who had surgically confirmed Hashimoto's thyroiditis between 1 March 2005, and 26 November 2005. In these patients, we reviewed the sonographic findings of the associated focal nodular lesion. Assessed were size, homogeneity, and echogenicity of the diseased thyroid gland and shape, echogenicity, margin, rim, microcal cification of the associated nodules. Without knowledge of the pathological diagnosis of the nodular lesions, based on the sonographic criteria, the nodules were classified as either malignant or benign. RESULTS: Hashimoto's thyroiditis demonstrates a variety of sonographic findings for size, homogeneity, and echogenicity. Among the nineteen nodules that were sonographically diagnosed and pathologically confirmed, nine papillary cancers, seven nodular hyperplasias, two Huthle cell adenomas, and one focal hyalinized fibrosing nodule were included. All of the nine papillary cancers showed more than one malignant finding such as marked hypoechogenicity, an irregular shape, a taller than wide shape, a spiculated margin, or microcalcifications that were classified as malignant nodulea, and all of the ten benign nodules showed no malignant findings. Circumscribed isoechoic, hyperechoic, or hypoechoic nodules without calcification were classified as bending nodules. CONCLUSION: Hashimoto's thyroiditis demonstrates various findings on a sonographic examination,and associated various benign and malignant lesions. Moreover, a sonographic examination is helpful to differentiate between malignant and benign lesions in Hashimoto's thyroiditis as in the normal thyroid.

Gray-Scale and Color Doppler US Features Corresponding to Histological Subtypes of Papillary Thyroid Carcinoma

PURPOSE: To compare the gray-scale and color or power Doppler ultrasonographic (US) features according to the histological subtypes of a papillary thyroid carcinoma (PTC). MATERIALS AND METHODS: The gray-scale and color or power Doppler US features of 159 surgically confirmed PTC (classic type of PTC, 69; classic type of papillary microcarcinoma [PMC], 67; and follicular variant of PTC [FVPTC], 23) in 118 patients were analyzed retrospectively. The following US characteristics were evaluated: the type of vascularization, echogenicity, outline, ratio of anteroposterior/transverse (AP/T) diameters, as well as the presence or absence of halo signs, cystic changes, and microcalcification. RESULTS: The most common type of vascularization was penetrating or central (75.4%) for the classic type of PTC, avascular (56.7%) for PMC, and peripheral and central (82.6%) for FVPTC. The echogenicity was most commonly hypoechoic (47.8%) for the classic type, hypoechoic (74.6%) for PMC, and isoechoic (30.4%) for FVPTC. The outline was most often irregular (60.9%) for the classic type, irregular (86.6%) for PMC, and regular (91.3%) for FVPTC. The ratio of the AP/T diameters was 1.0 or more in 31.9%, 55.2%, and 13.0%, a halo sign was observed in 30.4%, 6.0%, and 78.3%, cystic changes was present in 1.4%, 0%, and 21.7%, and microcalcifications were present in 55.1%, 28.4%, and 13.0% of those with the classic type, PMC, and FVPTC, respectively. CONCLUSION: The gray-scale and color Doppler US features corresponding to the histological subtypes of PTC are significantly different from one another. The US features of FVPTC appear to be significantly different from the other subtypes in that they tend to have more benign US characteristics than those of the classic type or PMC.

Gray-Scale and Color Doppler US Features Corresponding to Histological Subtypes of Papillary Thyroid Carcinoma

PURPOSE: To compare the gray-scale and color or power Doppler ultrasonographic (US) features according to the histological subtypes of a papillary thyroid carcinoma (PTC). MATERIALS AND METHODS: The gray-scale and color or power Doppler US features of 159 surgically confirmed PTC (classic type of PTC, 69; classic type of papillary microcarcinoma [PMC], 67; and follicular variant of PTC [FVPTC], 23) in 118 patients were analyzed retrospectively. The following US characteristics were evaluated: the type of vascularization, echogenicity, outline, ratio of anteroposterior/transverse (AP/T) diameters, as well as the presence or absence of halo signs, cystic changes, and microcalcification. RESULTS: The most common type of vascularization was penetrating or central (75.4%) for the classic type of PTC, avascular (56.7%) for PMC, and peripheral and central (82.6%) for FVPTC. The echogenicity was most commonly hypoechoic (47.8%) for the classic type, hypoechoic (74.6%) for PMC, and isoechoic (30.4%) for FVPTC. The outline was most often irregular (60.9%) for the classic type, irregular (86.6%) for PMC, and regular (91.3%) for FVPTC. The ratio of the AP/T diameters was 1.0 or more in 31.9%, 55.2%, and 13.0%, a halo sign was observed in 30.4%, 6.0%, and 78.3%, cystic changes was present in 1.4%, 0%, and 21.7%, and microcalcifications were present in 55.1%, 28.4%, and 13.0% of those with the classic type, PMC, and FVPTC, respectively. CONCLUSION: The gray-scale and color Doppler US features corresponding to the histological subtypes of PTC are significantly different from one another. The US features of FVPTC appear to be significantly different from the other subtypes in that they tend to have more benign US characteristics than those of the classic type or PMC.

Malignant Transformation of Nodular Hyperplasia in the Thyroid: A Case Report

Thyroid carcinogenesis is traditionally thought to originate 'de novo'. However, it is debatable whether a malignant transformation can possibly arise from a benign thyroid nodule, as suggested for the malignant transformation of a thyroid adenoma. To the best of our knowledge, no studies have been performed addressing the malignant transformation of nodular hyperplasia in the thyroid gland. Here, we report a case of nodular hyperplasia with focally malignant degeneration.