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.

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.

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.

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.

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.

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.

Usefulness of Screening Ultrasound for Thyroid Gland

PURPOSE: The purpose of this study was to investigate the usefulness of the ultrasonography as a screening test for thyroid diseases. MATERIALS AND METHODS: For 7 months, thyroid ultrasonography (7.5 MHz linear array) was performed prospectively by radiologists on 1,316 subjects who do not have a history of the thyroid disease. We analyzed the morphological abnormalities of thyroid gland and these were classified as the nodulal, cystic and diffuse types in accordance with the gender and ages of the patients. We performed ultrasound-guided fine needle aspiration in 21 patients who had sonographic features that were suggestive of malignant thyroid nodules. Physical examination was performed for all subjects by clinicians before the thyroid ultrasonography, and we compared the detectability of thyroid lesions between ultrasonography and physical examination. RESULTS: Thyroidal abnormalities were detected in 94 (7.1%) of 1,316 subjects. Among the 94 patients, 72 (5.5%) showed as nodules, 18 (1.4%) showed as cysts and 4 (0.3%) showed as diffuse abnormalities. The result of the ultrasound-guided aspiration on 21 patient showed 4 malignant nodules, 16 benign nodules and 1 undetermined nodule. Physical examination detected abnormalities in only 12 patients (12.8%) of the 94 patients, which were showed as nodules, cysts and the diffuse type by ultrasonography. CONCLUSION: Thyroid disease of the general population was relatively common and the detection rate with performing physical examination for the thyroid nodule, cyst and the diffuse type was lower than that for ultrasonography. Thyroid ultrasonography is a useful screening modality for detecting thyroid diseases.

Ultrasound-Guided Fine-Needle Aspiration Biopsy of Multiple Thyroid Nodules

PURPOSE: To standardize the number of nodules which necessitates ultrasound-guided, fine-needle, aspiration biopsy in patients who have multiple thyroid nodules with the same sonographic characteristics as each other. MATERIALS and METHODS: From February, 2002 to March, 2004, among patients whose diagnosis was confirmed by ultrasound-guided, fine-needle, aspiration biopsy, 545 nodules of 203 patients were found in sonography with more than two thyroid nodules. Each thyroid gland nodule was classified on a score from 0 to 2 points on the basis of the following 5 characteristics: internal content, margin, echogenicity, shape and calcification in sonography. When the score of all characteristics was the same, by deciding on nodules with the same sonographic char-acteristics and with the score of at least one characteristic being different, we divided the nodules with different sonographic characteristics in a patient. By methods such as given in the preceding descriptions, patients with multiple thyroid nodules were separated into two groups: one in which all nodules had the same sonographic characteristics and another in which nodules have at least one different sonographic characteristic. Then, each pathologic result was searched for the same case and different case in each patient group. RESULTS: Among the 203 patients who were diagnosed with multiple thyroid nodules in ultrasonography, 79 patients (38.9%) had nodules with the same ultrasonographic characteristics and 124 patients (61.1%) had nodules with at least one different ultrasonographic characteristic. All 79 patients' nodules with the same ultrasono-graphic characteristics in each patient showed the same pathologic result in all cases (100.0%) and there was no case showing a different pathologic result. Otherwise, among the 124 patients' nodules with different ultrasono-graphic characteristics, each patient showed the same pathologic result in 111 (89.5%) and different pathologic result in 13 (10.5%). CONCLUSION: In patients who have multiple thyroid nodules, if a patient's nodules have the same sonographic characteristics, we can perform ultrasound-guided, fine-needle, aspiration biopsy about only one nodule and if a patient's nodules have different sonographic characteristics from each other, we must perform the biopsy for all nodules.

US Guided Fine-needle Non-suction Technique: A Useful and Comfortable Method for Thyroid Nodule

as useful as the conventional suction technique for the cytopathological evaluation of thyroid nodules.

Patterns and Significance of Peripheral Calcifications of Thyroid Tumors seen on Ultrasound

PURPOSE: We wanted to analyze the peripheral calcification patterns of thyroid tumors that were seen on ultrasound and we also wanted to evaluate the clinical usefulness of the peripheral calcifications of the thyroid tumors. MATERIALS AND METHODS: We retrospectively analyzed 21 peripheral calcifications of the thyroid tumors of 18 patients; these were histopathologically confirmed by fine needle aspiration biopsy, automated gun biopsy and surgery. The peripheral calcification patterns were categorized into three types: type 1, peripheral nodular calcification, type 2, peripheral smooth rim calcification, and type 3, peripheral irregular rim calcification. The histopathologic results obtained during surgery, fine needle aspiration or automated gun biopsy were compared. RESULTS: Of the total 21 peripheral calcifications of thyroid tumors, 5 cases showed as being type 1 (24%), 3 cases showed as being type 2 (14%) and 13 cases showed as being type 3 (62%). Of the total 21 peripheral calcifications of the thyroid tumors, 18 were histopathologically confirmed as papillary carcinoma (86%). Among the type 1 peripheral calcification patterns, 3 cases were coincidentally diagnosed as papillary carcinoma and 2 cases were follicular neoplasm on the preoperative biopsy results and on the surgical results. Two cases of type 2 peripheral calcifications (67%) and three cases of type 3 peripheral calcifications (23%) were diagnosed as benign lesions upon preoperative biopsy, but the postoperative results were papillary carcinoma. CONCLUSION: Peripheral calcifications of thyroid tumors are important feature that suggest malignancy together with the microcalcification and peripheral calcifications of the type 2 and type 3 patterns, and these lesions may be difficult to accurately diagnose with using only biopsy.

Analysis of the Factor which Affect to Acquisiton Rate of Ultrasound-Guided Fine Needle Aspiration of Thyroid Nodules

PURPOSE: The purpose of this study is to evaluate the acquisition rate of adequate specimens in the ultrasoundguided percutaneous needle aspiration biopsy (US-PCNB) of thyroid nodules and to find the factors influencing the acquisition rate. MATERIALS AND METHODS: We conducted a prospective study in 132 patients who had a total of 215 nodules. Aspiration biopsy was performed with 21-gauge fine needles for 111 nodules (62 patients) and with 20-gauge cutting needles for 104 nodules (70 patients). We calculated the overall acquisition rate of adequate specimens of US-PCNB and compared the acquisition rates according to the kind of needle, and the size, nature and palpability of the nodules. RESULTS: The total acquisition rate of adequate specimens was 87.4%. There was no difference in the acquisition rate between the 20-gauge cutting needle and the 21-gauge needle. The acquisition rate of the solid nodules (90.2%) was higher than that of the cystic nodules (78.8%). However, the size and palpability of the nodules did not significantly affect the acquisition rate of the specimens. CONCLUSION: The acquisition rate of adequate specimens in the US-PCNB of thyroid nodules was high. The acquisition rate of the solid nodules was higher than that of the cystic nodules. However, there was no statistically significant difference in the acquisition rate according to the kind of needle, or the size and palpability of the nodules.

Ultrasound-Guided Fine Needle Aspirations of Thyroid Nodules: Assessment of Nondiagnostic Samples

PURPOSE: To determine the frequency of malignancy among the nondiagnostic specimens by ultrasound-guided, fine needle aspiration (US-FNA) and to analyze the factors which cause the nondiagnostic specimens of thyroid nodules. MATERIALS AND METHODS: Data were collected from 425 patients (58 male, 367 female) who underwent US-FNA of the thyroid nodule between February, 2002 and October, 2003. The study included 784 nodules from 425 patients. US-FNA was performed 1 to 3 times by two radiologists using a 10MHz linear probe and a 21-gauge fine needle. The percentage of total nondiagnostic specimens was obtained and the percentage of nondiagnostic specimens according to the thyroid nodule's size and nature was analyzed. Thyroid nodules were classified according to their sizes and natures. The nodules were divided by size as either 1cm or more, or less than 1cm in diameter. Each nodule was classified as cystic (pure cystic), mixed (solid portion of nodule2/3). The percentage of malignancy among nondiagnostic specimens was determined and compared to the malignancy rate among diagnostic specimens. Chi-square test and Fisher's exact test were used for statistical significance. RESULTS: Among the 784 nodules, 95 (12.1%) were nondiagnostic. The percentage of nondiagnostic specimens increased as the cystic content increased (p<0.0001). The malignancy rate of the diagnostic specimens was higher than that of the nondiagnostic specimens, but the difference was not significant. CONCLUSION: The cystic content of each nodule was the only significant predictor of nondiagnostic specimens. There was no significant difference in malignancy rate between nondiagnostic and diagnostic specimens. It is suggested that when evaluating an initially nondiagnostic US-FNA, repetitive US-FNA or follow-up USG should be performed.