Detection Of Malignant Thyroid Nodules Research Articles

Value of TI-RADS and elastography strain ratio in predicting malignant thyroid nodules: experience from a single center in Egypt

IntroductionThyroid nodules are highly prevalent in the general population; therefore, it is crucial to discriminate benign from malignant nodules. A practical thyroid imaging reporting and data system (TI-RADS) for thyroid nodules and ultrasound elastography are valuable tools not only for characterization of nodules but also for the selection of tumors for fine-needle aspiration cytology (FNAC).ObjectiveThis study aimed to evaluate the diagnostic accuracy of US evaluation in the prediction of malignant thyroid nodules and evaluate the role of the elastography score, strain ratio (SR), and the TI-RADS scoring system as non-invasive tools in differentiation between malignant and benign thyroid nodules.Material and methodsA total of 1269 patients were evaluated between February 2017 and April 2020 by a single expert thyroid ultrasound operator. The final diagnosis was achieved from cytological and/or histological evaluation and follow-up for at least 1 year.ResultsThere were 1088 females and 181 males with a mean age of 44 ± 10 SD. The final diagnosis was 1197 benign nodules and 72 malignant nodules. Most malignant nodules were scored elastography score 4 (83.3%) and TI-RADS category 5 (86.11%). We found that nodules with antero-posterior to transverse (A-P/T) diameter > 1, have 21 times more risk to be malignant than those with A-P/T diameter < 1, patients with solitary thyroid nodules have 4.5 times to develop malignancy compared to those with multinodular goiter (MNG), nodules with absent halo have 4 times more risk of malignancy. Furthermore, microcalcifications in thyroid nodules increase the risk of malignancy 9 times compared to those without calcifications. SR was found to be an excellent discriminator to differentiate between benign and malignant nodules with P < 0.001. Also, we found that for every unit increase in SR, the risk of malignancy increased by 20%. We reported that the accuracy of ultrasonography in the detection of malignant thyroid nodules had a sensitivity of 89%, specificity of 98%, 70% PPV, and 99.3% NPV, with an overall accuracy of 97.2%.ConclusionThe application of ultrasonographic non-invasive criteria for thyroid nodules in clinical practice might significantly reduce the number of unnecessary FNAC. Elastography, SR, and TI-RADS classification could be good predictors for malignant thyroid nodules.

Thyrotropin/Thyroglobulin ratio in combination with thyroid u/s to assess malignancy risk stratification of thyroid nodules

Objective: we aimed to asses if thyrotropin/thyroglobulin ratio has a significant value in detection of malignant thyroid nodules. Design: Retrospective analysis. Material and Methods: This study included finally 100 subject collected as outpatient’s endocrinology clinic of ALHuessine university hospital or admitted at oncology institute of Tanta. Patients who had history of thyroid diseases or surgery, those with abnormal levels of anti- thyroglobulin antibodies, cases without simultaneous measurement of serum anti Tg., with history of current use of thyroid hormone replacement therapy were excluded from this study. Clinico pathological features, as well as serumTSH, Tg, and TSH/Tg were compared between histopathologically benign and malignant groups. Results: Data related to 100 subjects (40%) normal and 60(60%) patients with thyroid nodules were analyzed, 30 patients (50%) were malignant thyroid nodules and 30 patients (50%) were benign.The malignant patients exhibited significantly higher TSH, TSH/Tg, , and a lower Tg compared to the benign patients (p&lt;0.05 for each). Conclusion: Preoperative TSH/Tg could be used as a predictive marker for differ-entiating between benign and malignant thyroid nodules.

Multi-channel convolutional neural network architectures for thyroid cancer detection.

Early detection of malignant thyroid nodules leading to patient-specific treatments can reduce morbidity and mortality rates. Currently, thyroid specialists use medical images to diagnose then follow the treatment protocols, which have limitations due to unreliable human false-positive diagnostic rates. With the emergence of deep learning, advances in computer-aided diagnosis techniques have yielded promising earlier detection and prediction accuracy; however, clinicians’ adoption is far lacking. The present study adopts Xception neural network as the base structure and designs a practical framework, which comprises three adaptable multi-channel architectures that were positively evaluated using real-world data sets. The proposed architectures outperform existing statistical and machine learning techniques and reached a diagnostic accuracy rate of 0.989 with ultrasound images and 0.975 with computed tomography scans through the single input dual-channel architecture. Moreover, the patient-specific design was implemented for thyroid cancer detection and has obtained an accuracy of 0.95 for double inputs dual-channel architecture and 0.94 for four-channel architecture. Our evaluation suggests that ultrasound images and computed tomography (CT) scans yield comparable diagnostic results through computer-aided diagnosis applications. With ultrasound images obtained slightly higher results, CT, on the other hand, can achieve the patient-specific diagnostic design. Besides, with the proposed framework, clinicians can select the best fitting architecture when making decisions regarding a thyroid cancer diagnosis. The proposed framework also incorporates interpretable results as evidence, which potentially improves clinicians’ trust and hence their adoption of the computer-aided diagnosis techniques proposed with increased efficiency and accuracy.

Use of an Easily Applicable Thyroid Imaging-Reporting and Data System (TI-RADS): Our Kwak TI-RADS Experience

Background: Early detection of malignant thyroid nodules is possible using ultrasonography (US)-guided fine needle aspiration biopsy (US-FNAB), which is a minimally invasive and easily applicable method. There are several guidelines based on the US findings, including the Thyroid Imaging-Reporting and Data System (TI-RADS), to identify patients requiring FNAB or patients with nodules suspicious of malignancy. Objectives: To emphasize the importance of the easily applicable Kwak TI-RADS classification system. Patients and Methods: In this cross-sectional study, the radiological and pathological findings of 641 consecutive patients, who underwent US-FNAB in our center, were retrospectively evaluated. The relationship between the cytological/histopathological results and the US findings was investigated using univariate and multivariate analyses. The results were also compared with the data in the literature. Results: In the univariate analysis, US features, including the presence of a solid component, hypoechogenicity, microlobulation or irregular margins, microcalcifications, and a taller-than-wide shape, were significantly associated with malignancy (P &lt; 0.05). However, in the multivariate analysis, only hypoechogenicity and a taller-than-wide shape significantly contributed to the diagnosis of malignancy (P &lt; 0.05). The malignancy rates of TI-RADS 3, 4a, and 4b lesions were lower in the present study compared to the literature. Conclusions: The US features, including the presence of a solid component, microcalcifications, hypoechogenicity, microlobulation or irregular margins, and a taller-than-wide shape, must be evaluated during US examinations. Besides, the widespread use of Kwak TI-RADS classification system, similar to the Breast Imaging-Reporting and Data System (BI-RADS), should be encouraged to provide a common tool for clinicians and prevent unnecessary surgical procedures.

BRAF V600E mutation and the Bethesda System for Reporting Thyroid Cytopathology of fine-needle aspiration biopsy for distinguishing benign from malignant thyroid nodules.

Background:The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) predicts the risk of malignancy for the different categories of the ultrasound-guided fine-needle aspiration biopsy (FNAB). The objective of this study is to investigate the efficiencies of the v-raf murine sarcoma viral oncogene homolog B1 (BRAF) V600E mutation test and the TBSRTC categories in distinguishing between benign and malignant thyroid nodules.Methods:In this study, 362 ultrasound-guided fine-needle aspiration (FNA) samples from 344 patients aged from 17 to 76 years old were retrospectively reviewed. The patients were classified into six groups (I–VI) according to the TBSRTC system. The amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) was used to evaluate the BRAF V600E mutation level in total 362 samples. Among of the 344 patients, 128 patients (131 thyroid nodules) who underwent surgeries were followed by histopathological examination. The predictive values of the BRAF V600E mutation test and TBSRTC categories were evaluated in these 131 thyroid nodules.Results:The median ages of the patients in the TBSRTC IV–VI group were smaller than those in the TBSRTC I–III groups. The proportion of nodules over 1 cm was larger than it in the TBSRTC IV group compared to the other groups. Significant differences in BRAF V600E mutation were observed (P < .001) among these six groups. The sensitivity (89.57%) for the detection of malignant thyroid nodules, negative predictive value (NPV; 45.45%) for the detection of benign nodules, and accuracy (86.26%) for distinguishing between benign and malignant thyroid nodules increased by combining the BRAF V600E mutation test and TBSRTC system when compared with the BRAF V600E mutation test and TBSRTC system respectively. The BRAF V600E mutation test alone demonstrated the increased positive predictive value (PPV; 98.91%) and specificity (93.75%) for the detection of malignant thyroid nodules compared to the TBSRTC method (alone or in combination with the BRAF V600E method).Conclusion:In summary, significant differences in age, nodule diameter, and BRAF V600E mutation were noted among the six categories of the TBSRTC system. The combination of the BRAF V600E mutation test and TBSRTC system demonstrated increases in the NPV, sensitivity, and accuracy, while the BRAF V600E method proved superiority to the TBSRTC system with regard to the PPV and specificity.

Quantitative Analysis of Galectin-3 Expression in Benign and Malignant Thyroid Nodules.

SUMMARYIn this study, galectin-3 was analyzed as a potential marker for preoperative detection of malignant thyroid lesions. Galectin-3 expression was analyzed by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR) in preoperative thyroid fine-needle aspirates from 245 patients with thyroid nodules. Out of 245 samples, 238 were adequate for analysis by RT-PCR. Galectin-3 was positive in 34 (89.5%) of 38 papillary carcinomas, 3 (89.5%) of 4 follicular carcinomas, 17 (53.1%) of 32 follicular adenomas, 2 (33.3%) of 6 Hurthle cell adenoma, 11 (28.2%) of 39 Hashimoto thyroiditis, and 69 (57.9%) of 119 nodular goiter samples. Galectin-3 showed specificity of 49.5%, sensitivity of 88.1%, positive predictive value of 27.2%, and negative predictive value of 95.1% as a marker for detection of malignant thyroid nodules. Owing to the relatively low positive predictive value due to the relatively high false positive rate, the clinical value of galectin-3 analyzed by quantitative real-time RT-PCR as a marker for preoperative detection of malignant thyroid lesions is limited.

HMGA2 Gene Expression in Fine-needle Aspiration Samples of Thyroid Nodules as a Marker for Preoperative Diagnosis of Thyroid Cancer.

There is a great interest in molecular markers that would help in the preoperative diagnosis of malignant thyroid nodules in cases of indeterminate fine-needle aspiration cytology. The aim of this study was to determine the diagnostic accuracy of HMGA2 gene expression in discriminating benign from malignant thyroid nodules. In this study, 237 preoperative thyroid fine-needle aspiration samples were analyzed prospectively for the expression of the HMGA2 gene by real-time reverse transcription polymerase chain reaction. The results were evaluated against the postoperative histopathologic diagnosis or definitive cytologic diagnosis in cases of nodular goiter and Hashimoto thyroiditis. Among 237 samples from patients with thyroid nodules that were analyzed, 231 were adequate for real-time reverse transcription polymerase chain reaction analysis. With a cutoff value of 8.71 for relative gene expression, HMGA2 was positive in 19 (16.4%) of 116 nodular goiter, 1 (2.6%) of 39 Hashimoto thyroiditis, 9 (28.1%) of 32 follicular adenoma, 0 (0%) of 5 Hurthle cell adenoma, 32 (88.9%) of 36 papillary carcinoma, and 3 (100%) of 3 follicular carcinoma samples. In discriminating between malignant and benign thyroid nodules, HMGA2 has shown specificity of 84.5%, sensitivity of 91.9%, positive predictive value of 53.1%, and negative predictive value of 98.2%. High sensitivity and negative predictive value of HMGA2 for preoperative detection of malignant thyroid nodules shown in this study indicate that it may have a role as an ancillary marker in cytology in the management of patients with thyroid nodules.

The comparison of accuracy of ultrasonographic features versus ultrasound-guided fine-needle aspiration cytology in diagnosis of malignant thyroid nodules

To compare the diagnostic accuracy of sonographic features with ultrasound-guided fine-needle aspiration (FNA) cytology in the detection of malignant thyroid nodules. This analytical cross-sectional study was conducted on patients with the diagnosis of thyroid nodule, who underwent ultrasound-guided FNA in Shahid Beheshti teaching hospital, Babol, northern Iran, between 2015 and 2017. The characteristics of the nodules obtained from ultrasonography were recorded. Regression analysis was used to assess the relation between sonographic findings and malignancy. We also used a receiver operator characteristics analysis to estimate the ability of ultrasound to predict the characteristic features of malignancy, as estimated by the area under the curve. In total, 898 thyroid nodules were included in the study, of which 55 (6.1%) were malignant and 843 (93.9%) were benign. There were significant positive associations between malignancy and hypoechogenicity [odds ratio (OR) 3.577, 95% confidence interval (CI) 2.045-6.256], fine calcification (OR 5.849, 95% CI 2.642-12.949), irregular margin (OR 4.366, 95% CI 2.284-8.345) and taller-than-wide shape (OR 5.199, 95% CI 2.125-12.721). The overall accuracies of hypoechogenicity, irregular margin, taller-than-wide shape and fine calcification were 0.804, 0.729, 0.705 and 0.575, respectively. According to the present study, the use of ultrasonography (along with ultrasound-guided FNA) is very effective in the diagnosis, follow-up, and indication for surgery of a thyroid nodule.

Diffusion-Weighted Magnetic Resonance Imaging for the Detection of Thyroid Cancer

BackgroundNodular thyroid disease possesses the potential to harbor malignancy. Our aim was to evaluate the significance of cervical diffusion-weighted magnetic resonance imaging (DW-MRI) for the detection of malignant thyroid nodules. MethodsSixty-five thyroid nodules from 58 patients who had undergone surgery were evaluated. Preoperative parameters, demographic data, ultrasound findings, fine-needle aspiration biopsy results and apparent diffusion coefficient (ADC) values of the nodules at DW-MRI were compared with the results from postoperative pathology examinations. ResultsThe “benign group” included 50 (76.9%) nodules, while 15 (23.1%) nodules constituted the “malignancy group”. Minimum, maximum and mean ADC values of the nodules were significantly lower in the malignancy group (P<.05). The best cutoff value for the mean ADC value was 1.33×10−3mm2/s, with a sensitivity of 66.67%, a specifity of 89.13%, a positive predictive value of 53.63% and a negative predictive value of 89.13%. A mean ADC value equal to or lower than 1.33×10−3mm2/s was associated with 9 times higher risk of malignancy (odds ratio: 9.111, 95% confidence interval: 2.49–33.21). ConclusionsThe ADC value detected by cervical DW-MRI can be considered a predictive parameter for the detection of thyroid cancer.

Utilidad de la resonancia magnética ponderada por difusión cervical en la detección del cáncer tiroideo

BackgroundNodular thyroid disease possesses the potential to harbor malignancy. Our aim was to evaluate the significance of cervical diffusion-weighted magnetic resonance imaging (DW-MRI) for the detection of malignant thyroid nodules. MethodsSixty-five thyroid nodules from 58 patients who had undergone surgery were evaluated. Preoperative parameters, demographic data, ultrasound findings, fine-needle aspiration biopsy results and apparent diffusion coefficient (ADC) values of the nodules at DW-MRI were compared with the results from postoperative pathology examinations. ResultsThe “benign group” included 50 (76.9%) nodules, while 15 (23.1%) nodules constituted the “malignancy group”. Minimum, maximum and mean ADC values of the nodules were significantly lower in the malignancy group (p < 0.05). The best cutoff value for the mean ADC value was 1.33 × 10-3 mm2/s, with a sensitivity of 66.67%, a specifity of 89.13%, a positive predictive value of 53.63% and a negative predictive value of 89.13%. A mean ADC value equal to or lower than 1.33 × 10-3 mm2/s was associated with 9 times higher risk of malignancy (odds ratio: 9.111, 95% confidence interval: 2.49-33.21). ConclusionsThe ADC value detected by cervical DW-MRI can be considered a predictive parameter for the detection of thyroid cancer.

Quantitative Analysis of Dynamic Power Doppler Sonograms for Patients with Thyroid Nodules

To clarify and determine whether power Doppler sonograms are useful for the detection of malignant thyroid nodules, a computerized quantification method was used to evaluate the vascular density of a thyroid nodule in a prospective setting. Sonographic power Doppler images were collected in consecutive frames (45 frames of images), and a proprietary program (AmCAD-UV) was implemented using methods proposed in this article automatically calculated a quantified power Doppler vascular index (PDVI). The minimum PDVI value (PDVImin) was suggested as a measure of the vascular density of the nodule. The vascular densities of the peripheral and central areas of the nodule, referred to as central PDVImin and Ring PDVImin, respectively, were also evaluated. For 238 tumors (79 malignant and 159 benign) from 208 patients, all of the proposed indices of benign lesions were significantly higher than those of the malignant lesions. The area under the receiver operating characteristic curve (AUC) reaches 71% with the PDVImin. When the vascular patterns were further classified into intra-nodular and peripheral vascularity types, no vascularity type was observed significantly more frequently in malignant nodules than in benign nodules. These proposed computerized vascular indices provide a quantification method to objectively evaluate thyroid nodules and have potential as predictors of thyroid malignancy. The conventional vascular characterizations of malign nodules, that is, more vessels are observed in malignant nodules than in benign nodules, are shown to be unreliable in our study. Instead, a higher value of the quantified power Doppler vascular density was observed in benign nodules.

Accuracy of Ultrasound Elastography in the Diagnosis of Thyroid Cancer in a Low-risk Population

Stiffness has been associated to malignancy in prostate and breast, as well as thyroid. Ultrasound elastography objectively measures tissue elasticity, and previous studies have described it as a high sensitivity and specificity technique for the detection of malignant thyroid nodules in high-risk populations. The aim was to assess the accuracy of elastography in a population with low risk of malignancy. 128 consecutive patients with nodular goiter were recruited. Elastography and ultrasound-guided fine-needle aspiration were performed. When malignancy was suspected by citology, surgery was recommended. Thyroid nodules were classified by elastography according the criteria described by Ueno, and an alternative classification. Sensitivity, specificity, predictive values, and odds ratio were calculated. Most patients were female, aged 56.1 year, with single nodule (52.0%) or multinodular goiter (45.6%), and a few thyroiditis (2.4%). The majority of nodules were mostly elastic. Fine-needle aspiration found 86% of benign nodules, 9.3% of indeterminate, and 4.7% possibly malignant. After surgery, 3 malignant nodules were confirmed, all of them being papillary carcinomas. All the malignant nodules were mostly elastic, as well as 75% of indeterminate nodules. Low values of sensitivity and specificity were found for elastic nodules being benign and hard nodules malignant. In a low-risk population for thyroid cancer, elastography lacks accuracy for the diagnosis of malignant nodules.

Role of Ultrasound Elastography in Prediction of Malignancy in Thyroid Nodules

Background. Ultrasonography is considered useful to distinguish between solid and cystic thyroid nodules and to stratify a nodule’s risk of cancer as low, medium, or high. Ultrasound (US) elastography has been applied to study the hardness/elasticity of nodules to differentiate malignant from benign lesions. Elastography possibly can solve the dilemma in reaching an accurate diagnosis for the cytologically known as indeterminate nodules. Aim. To evaluate the sensitivity and specificity of US elastography in the diagnosis of thyroid cancer. Patients and methods. This prospective study included 40 patients. The total number of nodules was 46, they were all euthyroid. Laboratory investigations were done including FT3, FT4, and TSH to exclude hot nodules. Neck US, US elastography, and fine-needle aspiration were done to all patients, and US elastography scoring system from 1 to 4 was used. Results. Four out of the 46 studied nodules were malignant. The ROC curve for elastography score (E-score) showed high sensitivity, specificity for the diagnosis of malignant thyroid nodules with a cut-off value of E-score 4 and high significance (p < 0.001), the area under curve was 0.92. The sensitivity was 75.0% and specificity was 100%. For E-score more than 2, the sensitivity was 100% and specificity was 85.37%. Conclusion. US elastography can be used to increase both the sensitivity and the specificity of US for the detection of malignant thyroid nodules, and so it seems to have great potential as a new tool for the diagnosis of thyroid cancer.

Utility and Interobserver Agreement of Ultrasound Elastography in the Detection of Malignant Thyroid Nodules in Clinical Care

Utility and Interobserver Agreement of Ultrasound Elastography in the Detection of Malignant Thyroid Nodules in Clinical Care

Utility and Interobserver Agreement of Ultrasound Elastography in the Detection of Malignant Thyroid Nodules in Clinical Care

Malignancy correlates with hardness of tissues and US elastography can potentially analyze the stiffness of lesions. Our aim was to evaluate the utility of US elastography in the detection of malignant nodules and to investigate interobserver agreement with this technique. One-hundred three consecutive patients with 106 thyroid nodules were examined prospectively with conventional B-mode sonography and real-time US elastography. All patients were referred for FNAB. Conventional B-mode sonography and US elastographic examinations were performed, and images were separated and independently interpreted by 2 radiologists blinded to pathologic results. US elastogram evaluation was based on a simplified classification of stiffness based on gray-scale patterns, tumor size compared with B-mode, and margins. Interobserver agreement was studied. FNAB was used as the reference standard for the diagnosis of benign nodules, but histopathologic evaluations were performed when results suspicious for malignancy or malignant results were obtained on FNAB as well as in indeterminate lesions. In our study, pattern of stiffness based on gray-scale and classification proposed were statistically significant and predicted malignancy with 100% sensitivity and 40.6% specificity. Tumor size when compared with B-mode images or margins was not statistically significant in our study. No false-negatives were found, and an NPV of 100% was seen. Interobserver agreement for US elastography was excellent in our study, with a κ index of 0.82 (95% CI). We believe that US elastography is a promising technique that can assist in the evaluation of thyroid nodules and can potentially diminish the number of FNAB procedures needed. We believe that it may be useful to introduce US elastography into routine clinical practice.

Predictive Value of Sonographic Features in Preoperative Evaluation of Malignant Thyroid Nodules in a Multinodular Goiter

The primary goal of ultrasonography (US) in the evaluation of a thyroid nodule is to determine its malignancy, although the diagnosis of a malignant nodule on the basis of US alone is nearly impossible. The aim of this prospective study was to evaluate the predictive value of sonographic features in the preoperative diagnosis of malignant thyroid nodules, and to determine the important features of sonography. This prospective study included 550 consecutive patients with , thyroid nodules. Nodules were divided into two groups on the basis of pathological diagnosis: group 1 consisted of 1,633 nodules with a benign pathology, and group 2 consisted of 293 nodules with a malignant pathology. Microcalcifications, blurred nodular margins, and solid and hypoechoic appearance were more common in malignant nodules compared to benign nodules (89.1% versus 5%; 64.5% versus 4.7%; 81.6% versus 30.6% ; and 62.5% versus 43.1%, respectively; p < 0.001). There was a positive correlation between the detection of malignant thyroid nodules and microcalcification (rs = 0.791, p = 0.0001), blurred nodular margin (rs = 0.625, p = 0.0001), solid appearance (rs = 0.376, p = 0.0001), and hypoechoic appearance (rs = 0.141, p = 0.0001). Microcalcifications, blurred nodular margins, and solid and hypoechoic appearance were independent determinants of malignancy upon US examination of thyroid nodules (OR: 159, OR: 37, OR: 9.9, and OR: 2.2, respectively). Although we did not identify a single feature indicative of malignancy in the sonographic examination of nodules, microcalcification and blurred margin were the strongest correlates for malignancy.

Characterization of Follicular Thyroid Nodules at Fine Needle Aspiration Biopsy Using Double Phase Thallium-201 Imaging: Comparison of Visual and Semiquantitative Analyses

To compare visual and semiquantitative indices of double phase thallium-201 thyroid scintigraphy (DTS) for differentiation of malignant nodules by indeterminate fine needle aspiration biopsy (FNAB) results. DTS (early; 15 minutes; delayed, 2 hour) were performed after injection of 37MBq of thallium-201 in 60 patients with indeterminate FNAB. With grade 4 and 5, sensitivity and specificity were 51.4% and 78.3%, respectively. With early lesion to nonlesion ratio (L/N) 1.49, sensitivity and specificity were 97.3% and 39.1%, respectively. With delayed L/N 1.89, sensitivity and specificity were 70.3% and 78.3%, respectively. With wash-out rate (WR) 18.93%, sensitivity and specificity were 89.2% and 82.6%. Early L/N was superior to delayed L/N and WR for the detection of malignant thyroid nodules. Visual assessment had a limited value for differentiation of follicular nodules. The optimal semiquantitative indices were 1.49 for early L/N and 1.89 for delayed L/N. Also, optimal WR was 18.93%. The early L/N was superior to delayed L/N and WR for the detection of malignant thyroid nodular lesions. However, visual assessment and early L/N of DTS showed similar results. Visual analysis and semiquantitative indices of DTS could not differentiate follicular carcinoma and follicular variant of papillary thyroid cancer.

The Usefulness of High Resolution Ultrasonography in the Differentiation of Thyroid Nodule

Background: Fine needle aspiration (FNA) is regarded as the best procedure in the diagnosis of thyroid malignancies. However, the rate of false negative and indeterminate results are between 5~10 and 10~30%, respectively. Therefore, a new diagnostic tool to assist FNA is required. Recently, high resolution ultrasonography (US) has become a useful tool in the detection of malignant thyroid nodules. Therefore, the sonographic characteristics differentiating malignant from benign nodules were analyzed, and the usefulness of US in the diagnosis of thyroid malignancy assessed. Methods: Of the 212 patients that underwent surgery due to a thyroid nodule, at the Daegu Catholic University Hospital between January 2002 and June 2004, and 181 patients (199 nodules) who underwent high resolution US examination before surgery, were included in this study. The characteristics of the sonographic parameters, such as depth/width ratio, shape, margin, structure, sponge sign, calcification and halo, and the homogeneity and echogenicity of the solid component and invasion, were observed. Results: In a univariate analysis of the nonfollicular neoplasms, the depth/width ratio, shape, margin, structure, calcification and halo, and the homogeneity and echogenicity of the solid component were found to be significant parameters. The “sponge sign”, a new parameter suggested by us, was found only in benign nodules. In a multiple logistic regression analysis, only the depth/width ratio, shape, presence of calcification and echogenicity of the solid component were significant parameters. According to the results of the multiple logistic regression analysis, the point and estimate of each characteristic of the significant parameters were found, and a formula for calculating a score for the prediction of malignancy computed. At a score of 0.44, the sensitivity and specificity of US were 85.9 and 88.7%, respectively. In a univariate analysis of follicular neop-lasms, the shape, calcification and echogenicity were found to be significant parameters. Conclusion: It was conclude that high resolution US is a very useful tool in the differentiation of benign and malignant nodules, especially in nonfollicular neoplasms. It is also suggested that the “sponge sign” might be used as a strong indicator for the confirmation of benign nodules (J Kor Soc Endocrinol 20:242～251, 2005).

Thallium-201 scintigraphy in the evaluation of thyroid nodules. A retrospective study of 246 cases.

There is controversy at present concerning the value of Tl-201 scintigraphy in the diagnosis of malignant thyroid nodules. The usefulness of Tl-201 scintigraphy in differentiating benign from malignant nodules was evaluated retrospectively. Tl-201 scintigraphy was performed in 101 patients with malignant thyroid nodules and in 145 with benign nodules. Early and late images were examined to compare Tl-201 uptake in nodules and normal thyroid tissue. The visual method resulted in 74% of sensitivity and 58% of specificity for the detection of malignant nodules including incidental cancers. Excluding incidental cancers, 87% sensitivity and 58% specificity were achieved. Small cancers, including incidental cancers less than 1.5 cm in diameter and small number of viable tumor cells in a large tumor also gave negative Tl-201 scintigraphic results. Forty-two percent of the benign lesions gave false positive Tl-201 scintigraphic results. It is concluded that Tl-201 scintigraphy is a sensitive and useful method to use in diagnosing malignant thyroid nodules, but is not a specific method even with late scan, for the detection of malignant thyroid nodules.