Diagnostic value of elastosonographically determined strain index in the differential diagnosis of benign and malignant thyroid nodules

The role of elastography in the assessment of thyroid nodules in acromegaly

BACKGROUND

Nodular thyroid disease is a frequent finding seen in patients with acromegaly. Ultrasound-elastography (US-E) appears to be a helpful tool for the diagnosis of thyroid cancer. The aims of this study were to evaluate thyroid nodules in acromegaly and to assess the diagnostic accuracy of US-E in detecting thyroid cancer in this population.

METHODS

US-E was applied to 166 nodules detected in 102 acromegalic patients and to 105 nodules found in 95 nonacromegalic subjects. The lesions were classified according to the elasticity scores (ES) as soft (ES 1-2) or hard (ES 3-4).

RESULTS

: Mean age was 55.1 ± 12.47 years [59 (58%) women]. The prevalence of hard nodules (ES 3 and 4) was significantly higher in the group of acromegalic patients than in control subjects (48% to 20%, p < 0.001). Mean ES was higher in patients with acromegaly (2.45 to 2.22, p: 0.001), however, the mean strain index (SI) was similar between groups (1.53 to 1.65, p: 0.204).

DISCUSSION

Thyroid nodules in acromegaly patients have a higher elasto score and the prevalence of hard nodules is higher in active disease. However, increased stiffness of nodules by US-E in patients with acromegaly does not seem to estimate the malignancy of the nodules.

US-Elastography With Different Techniques for Thyroid Nodule Characterization: Systematic Review and Meta-analysis

Background

Thyroid nodules are frequent in adult population and thyroid cancer incidence has increased dramatically over the past three decades. The aim of this systematic review and meta-analysis was to evaluate the US-Elastosonography (USE) diagnostic performance in assessing the thyroid nodules malignancy risk.

Methods

PubMed and Embase databases were searched from January 2011 to July 2021. We extracted data from selected studies and calculated the overall diagnostic accuracy of qualitative USE, semi-quantitative USE and quantitative USE. Summary receiver operating characteristic (ROC) curve was elaborated to show the results. All statistical tests were performed using Metadisc and Medcal software package.

Results

Finally 72 studies with 13,505 patients and 14,015 thyroid nodules (33% malignant) undergoing elastography were included. The pooled sensitivity, specificity and AUC were 84%, 81%, and 0.89 respectively for qualitative USE; 83%, 80%, and 0.93 for semi-quantitative USE and 78%, 81% and 0.87, for quantitative USE. The qualitative and semiquantitative USE present very similar diagnostic accuracy values and both better than the quantitative USE.

Conclusions

USE is a useful imaging tool for thyroid nodule characterization. In accordance with recent guidelines and meta-analyses, the USE could be used daily in thyroid nodule malignancy risk stratification.

Systematic Review Registration

PROSPERO: CRD42021279257.

Ultrasound Parameters of Thyroid Nodules and the Risk of Malignancy: A Retrospective Analysis

Ultrasonography-guided fine-needle aspiration biopsy is the common choice for diagnosis of the suspected thyroid nodule. An algorithm(s) that finds the malignant potential of a nodule preoperatively, to overcome unnecessary diagnostic methods, does not exist. The objective of the study was to correlate thyroid nodule sizes measured by ultrasonography and risk of malignancy assessed by cytologic and histologic examinations. Data regarding fine-needle aspiration cytology and the results of histologic examinations of surgical specimens of 260 nodules were collected and analyzed. The macro or multiple calcifications, the complex echo pattern, and posterior region homogeneity were considered suspicious in ultrasonography. Bethesda system for classification of thyroid nodules was used for cytopathology. Histopathology performed as per the 2004 World Health Organization classification system. The benefit score analysis was performed for determination of clinical usefulness. Twenty-eight of 49 malignant nodules and 46 of 68 malignant nodules detected through ultrasound following fine-needle aspiration cytopathology and histopathology were <2 cm in size. A correlation was found for malignancy rate detected by ultrasonography-guided fine-needle aspiration cytology and those of the surgical specimen (r = 0.945, P = .015, R² = 0.894). Ultrasonography-guided fine-needle aspiration cytology had 0.994 sensitivities, 0.721 accuracies, and 0.08 to 0.945 diagnostic confidence for the detection of malignant nodules. Nodule size less than 2 mm (P = .011) was associated with the malignancy potential of thyroid nodules. Ultrasonography-guided fine-needle aspiration cytology had 19 (7%) results as a false negative and 1 (1%) results were false positive. Ultrasound-guided fine-needle aspiration cytopathology reported oversize of thyroid nodule than original but can predict the risk of malignancy. Level of Evidence: III.

Can the unnecessary operations for suspected thyroid nodules be avoided by the combined use of the strain ratio and elastography score?

Introduction

Only 5%–15% of thyroid surgical specimens are reported as malignant. Most of the operations are performed due to suspicion of malignancy as a result of fine needle aspiration biopsy but invasiveness, non-diagnostic results and potential repeat biopsies are disadvantages of fine needle aspiration biopsy.

Objective

The aim of this study was to investigate the effectiveness of simultaneously using both the strain ratio and elasticity score in the differential diagnosis of thyroid nodules, as well as to assess the compatibility of these two methods.

Methods

A total of 144 nodules were included in the study. The final histopathologic diagnosis was used as the reference standard. The area under the curve sensitivity, specificity, and cut-off values of the strain ratio and elasticity score were determined using receiver operating characteristic curve analysis. The compatibility and comparison of strain ratio and elasticity score were also performed.

Results

Twenty eight nodules (19.4%) were malignant. The strain ratio and elasticity score results were found to be significantly successful in predicting thyroid malignancy (p < 0.001 for both). Moreover, the area under the curve for the strain ratio and elasticity score were found to be 0.944 and 0.960, respectively. The diagnostic accuracy of the elasticity score was found to be superior to that of the strain ratio, but this difference was not statistically significant (p = 0.456). When the compatibility of the strain ratio and elasticity score was examined, the two evaluations were revealed to be statistically consistent with each other (Kappa = 0.767; p < 0.001). When the strain ratio and the elasticity score were used together, the specificity of capturing the correct diagnosis increased from 84.5% to 93.1%.

Conclusion

When the strain ratio an elasticity score were used together for the differential diagnosis of thyroid nodules, more accurate results were obtained. Thus, combining both methods may be a promising alternative to fine needle aspiration biopsy in order to prevent unnecessary surgical interventions for suspected thyroid nodules.

Biomechanical properties of optic nerve and retrobulbar structures with 2D and 3D shear wave elastography in patients affected by glaucoma

This study consists of an elastosonography evaluation of both eyes of 40 glaucomatous patients and 40 healthy subjects. We used shear wave elastography with a one-dimensional-array probe to capture two-dimensional images in order to study the optic nerve near the papilla, chorioretinal complex, lateral rectus muscle, and periorbital fat tissue. Furthermore, we used a two-dimensional array probe to capture three-dimensional images to study the optic nerve in toto with multilevel sampling. We obtained qualitative and quantitative data ("absolute" stiffness values). Then, we have investigated these tissue also measuring the "stiffness ratio" values. Statistically significant differences (p < 0.05), between glaucomatous patients and healthy patients, were noted in "absolute" stiffness values in the two-dimensional analysis at the emergence of the optic nerve and chorioretinal complex, and in the three-dimensional analysis at the emergence of the optic nerve (level I°). This result was supported by the statistically significant differences in the "stiffness ratio" values between the optic nerve and the adjacent adipose tissue, obtained both in two- and three-dimensional analyses. Data were subsequently compared with diagnostic tests currently used for glaucoma, which showed a sensitivity of 83% and specificity of 80% relative to those of elastosonography. We propose the use of elastosonography to verify the existence of pathological changes in the mechanical and elastic properties of peri-ocular structures and their variations as a complementary tool in the diagnosis of glaucoma and for follow-up during treatment.

Use of strain ultrasound elastography versus fine-needle aspiration cytology for the differential diagnosis of thyroid nodules: a retrospective analysis

OBJECTIVE

Fine-needle aspiration cytology is the risk stratification tool for thyroid nodules, and ultrasound elastography is not routinely used for the differential diagnosis of thyroid cancer. The current study aimed to compare the diagnostic parameters of ultrasound elastography and fine-needle aspiration cytology, using surgical pathology as the reference standard.

METHODS

In total, 205 patients with abnormal thyroid function test results underwent ultrasound-guided fine-needle aspiration cytology on the basis of the American College of Radiology Thyroid Imaging-Reporting and Data System classification and strain ultrasound elastography according to the ASTERIA criteria. Histopathological examination of the surgical specimens was performed according to the 2017 World Health Organization classification system. Moreover, a beneficial score analysis for each modality was conducted.

RESULTS

Of 265 nodules, 212 measured ≥1 cm. The strain index value increased from benign to malignant nodules, and the presence of autoimmune thyroid diseases did not affect the results (p>0.05 for all categories). The sensitivities of histopathological examination, ultrasound elastography, and fine-needle aspiration cytology for detection of nodules measuring ≥1 cm were 1, 1, and 0.97, respectively. The working area for detecting nodule(s) in a single image was similar between strain ultrasound elastography and fine-needle aspiration cytology for highly and moderately suspicious nodules. However, for mildly suspicious, unsuspicious, and benign nodules, the working area for detecting nodule(s) in a single image was higher in strain ultrasound elastography than in fine-needle aspiration cytology.

CONCLUSION

Strain ultrasound elastography for highly and moderately suspicious nodules facilitated the detection of mildly suspicious, unsuspicious, and benign nodules.

Ultrasound elastography score and strain index in different parathyroid lesions

BACKGROUND

Despite significant improvement in imaging quality and advanced scientific knowledge, it may still sometimes be difficult to distinguish different parathyroid lesions. The aims of this prospective study were to evaluate parathyroid lesions with ultrasound elastography and to determine whether strain index can help to differentiate parathyroid lesions.

METHODS

Patients with biochemically confirmed hyperparathyroidism and localised parathyroid lesions in ultrasonography were included. All patients underwent B-mode US and USE examination. Ultrasound elastography scores and strain index of lesions were determined. Strain index was defined as the ratio of strain of the thyroid parenchyma to the strain of the parathyroid lesion.

RESULTS

Data of 245 lesions of 230 patients were analysed. Histopathologically, there were 202 (82.45%) parathyroid adenomas, 26 (10.61%) atypical parathyroid adenomas, and 17 (6.94%) cases of parathyroid hyperplasia. Median serum Ca was significantly higher in atypical parathyroid adenoma patients than parathyroid hyperplasia patients (P = 0.019) and median PTH was significantly higher in APA compared to PA patients (P < 0.001). In 221 (90.2%) of the parathyroid lesions, USE score was 1 or 2. The median SI of atypical parathyroid adenomas was significantly higher than parathyroid adenomas and hyperplasia lesions (1.5 (0.56-4.86), 1.01 (0.21-8.43) and 0.91 (0.26-2.02), respectively, P = 0.003).

CONCLUSION

Our study revealed that SI of parathyroid lesions as well as serum calcium, parathyroid hormone levels, and B-mode US features may help to predict the atypical parathyroid adenoma. Ultrasound elastography can be used to differentiate among parathyroid lesions and guide a surgical approach.

Which Is the Best Reference Tissue for Strain Elastography in Predicting Malignancy in Thyroid Nodules, the Sternocleidomastoid Muscle or the Thyroid Parenchyma?

OBJECTIVES

This study aimed to compare 2 types of strain ratios (SRs) in thyroid nodules. Two reference points were used: the sternocleidomastoid (SCM) muscle and the thyroid parenchyma.

METHODS

A total of 101 nodules in 83 patients were prospectively enrolled in the study. For the semiquantitative analysis, 2 types of SRs were used: SR1, the ratio of the SCM muscle strain to the thyroid nodule strain; and SR2, the ratio of the surrounding normal thyroid tissue strain to the thyroid nodule strain. For each nodule, the SR1 and SR2 elastographic values were calculated, and their averages were compared.

RESULTS

Eighty-one (80.2%) of 101 thyroid nodules were benign, and 20 (19.8%) were malignant. In both benign and malignant histopathologic types, the SR1 averages were significantly higher than the SR2 averages (P = .001; P < .001, respectively). Both the SR1 and SR2 values were found to be significantly successful in differentiating benign from malignant histopathologic types (P < .001 for both). The areas under the curve were then compared for the methods, and the difference was found to be statistically significant (P = .046). The diagnostic accuracy of the SR1 was superior to that of the SR2.

CONCLUSIONS

The SR1 and SR2 are effective adjunctive diagnostic tools for identifying malignant thyroid nodules. Using the SCM muscle as a reference point instead of thyroid tissue may be a more valuable way to measure SRs.

Qualitative and Semiquantitative Elastography for the Diagnosis of Intermediate Suspicious Thyroid Nodules Based on the 2015 American Thyroid Association Guidelines

OBJECTIVES

To evaluate qualitative and semiquantitative elastography for the diagnosis of intermediate suspicious thyroid nodules based on the 2015 American Thyroid Association (ATA) guidelines.

METHODS

Through a retrospective search of our institutional database, 746 solid thyroid nodules found on grayscale ultrasonography, strain elastography, and ultrasound-guided fine-needle aspiration between June and November 2009 were collected. Among them, 80 nodules from 80 patients with an intermediate suspicion of malignancy based on the 2015 ATA guidelines that were 10 mm or larger were recruited as the final study nodules. Elastographic findings were categorized according to the criteria of Rago et al (J Clin Endocrinol Metab 2007; 92:2917-2922) and Asteria et al (Thyroid 2008; 18:523-531), and strain ratio values were calculated and recorded. The independent 2-sample t test and χ² test (or Fisher exact test) were used to evaluate differences in clinical parameters between benign and malignant thyroid nodules. All variables were compared by univariate and multivariate logistic regression analyses, and odds ratios with 95% confidence intervals were calculated.

RESULTS

Of the 80 nodules, 6 (7.5%) were malignant, and 74 (92.5%) were benign. No significant differences were observed in age, sex, nodule size, elasticity score, and strain ratio between benign and malignant nodules. No variables significantly predicted thyroid malignancy on the univariate analysis. On the multivariate logistic regression analysis, there were no independent variables associated with thyroid malignancy, including the elasticity score and strain ratio (all P > .05).

CONCLUSIONS

Elastographic analysis using the elasticity score and strain ratio has limited ability to characterize the benignity or malignancy of thyroid nodules with an intermediate suspicion of malignancy based on the 2015 ATA guidelines.

Application of high-resolution ultrasound, real-time elastography, and contrast-enhanced ultrasound in differentiating solid thyroid nodules

High-resolution ultrasound (HRUS) is a sensitive tool for identifying thyroid nodules. Real-time elastography (RTE) and contrast-enhanced ultrasound (CEUS) are newly developed methods which could measure tissue elasticity and perfusion features. The aim of the present study was to evaluate and compare the diagnostic efficiency of HRUS, RTE, CEUS and their combined use in the differentiation of benign and malignant solid thyroid nodules.In total, 111 consecutive patients with 145 thyroid nodules who were scheduled for surgery were included in the study. All of them underwent HRUS, RTE, and CEUS examination. The independent ultrasound (US) predictors for malignancy were determined and quantified using logistic regression analysis, based on which a risk-scoring model was established for each method. The diagnostic efficiency of each method was assessed by receiver operating characteristic (ROC) curve analysis.HRUS showed the best diagnostic efficiency among the 3 US methods, with 74.6% sensitivity and 87.8% specificity. CEUS had higher sensitivity (85.7%), whereas RTE alone did not show much advantage. Combined use of RTE and HRUS increased the sensitivity (92.1%). The HRUS-RTE-CEUS combination could increase both the sensitivity and specificity (87.3%, 91.5%), with the best AUC (0.935) among all the methods.The overall diagnostic value of HRUS in predicting malignancy is the best among the 3 US methods. Combined use of RTE and CEUS and HRUS could improve the diagnostic efficiency for solid thyroid nodules.

Ultrasound Strain Elastography for Circumscribed Solid Thyroid Nodules without Malignant Features Categorized as Indeterminate by B-Mode Ultrasound

The aim of this study was to evaluate the diagnostic performance of ultrasound strain elastography (USE) for circumscribed solid thyroid nodules without malignant or benign features seen on US. This retrospective study included 197 thyroid nodules in 196 patients who underwent USE with color mapping and strain ratio measurement between 2010 and 2014. Of the 197 nodules, 24 (12.2%) were malignant. No significant differences in color mapping or strain ratio were observed between benign and malignant nodules. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 29.2% (95% confidence interval [CI]: 13.8%-49.4%), 77.5% (95% CI: 75.3%-80.3%), 15.2% (95% CI: 7.2%-25.8%), 88.7% (95% CI: 86.3%-92.0%), and 71.6% (95% CI: 67.8%-76.5%) for color mapping and 50.0% (95% CI: 30.%-69.5%), 57.2% (95% CI: 54.5%-59.9%), 14.0% (95% CI: 8.5%-18.4%), 89.2% (95% CI: 85.0%-93.4%) and 56.3% (95% CI: 51.6%-61.1%) for strain ratio measurement, respectively. USE with color mapping and strain ratio measurement has a limited ability to differentiate benign from malignant nodules for circumscribed solid thyroid nodules without definite malignant features categorized as indeterminate by B-mode US.

Virtual Touch Tissue Imaging for Differential Diagnosis of Thyroid Nodules: Additional Value of the Area Ratio

OBJECTIVES

To evaluate the additional value of the area ratio on Virtual Touch tissue imaging (VTI; Siemens Medical Solutions, Mountain View, CA) for diagnosis of thyroid nodules referred to surgery.

METHODS

From April 2013 to February 2014, 205 consecutive patients with 225 histologically proven thyroid nodules were enrolled in this retrospective study. Virtual Touch tissue imaging and area ratio measurements were performed for each nodule. The area ratio was defined as the area of the nodule on VTI divided by the area on B-mode sonography. Nodule stiffness on VTI was graded from I (soft) to VI (hard). Receiver operating characteristic curve analyses of VTI, area ratio, and the combination of VTI and area ratio were performed. The sensitivity, specificity, accuracy, positive predictive value (PPV), negative predictive value (NPV), and Youden index were also evaluated.

RESULTS

By receiver operating characteristic curve analyses, the cutoff values were VTI grade IV and area ratio of 1.09, respectively. Nodules with VTI grade IV or higher or area ratio of 1.09 or higher were more likely to be malignant. The sensitivity, specificity, accuracy, PPV, NPV, and Youden index were 78.6%, 92.3%, 88.0%, 82.1%, 90.5%, and 0.709 for VTI and 81.4%, 87.1%, 85.3%, 74.0%, 91.2%, and 0.685 for area ratio (all P > .05). However, when using the criterion of VTI grade IV or higher and area ratio of 1.09 or higher as a combination, the sensitivity, specificity, accuracy, PPV, NPV, and Youden index increased to 94.3%, 97.4%, 96.4%, 94.3%, 97.4%, and 0.917 (all P< .05 compared to VTI or area ratio alone, except for specificity between VTI and the combination).

CONCLUSIONS

The diagnostic performance of VTI grading and the area ratio for differentiation between benign and malignant thyroid nodules is equivalent. The performance is further improved with a combination of VTI grading and area ratio analysis.

Sonographic Elastography of the Thyroid Gland

Thyroid gland disorders include benign and malignant thyroid nodules and diffuse thyroid disorders. The incidence of malignant thyroid nodules is low and the prognosis is good. The diagnosis of thyroid cancer and diffuse parenchymal disorders is generally based on clinical manifestations and histopathological evaluation. Ultrasonography has its place in the diagnostics and follow-up of thyroid disorders. Ultrasonographic elastography is a new, developing method that shows increase in clinical practice. In this study, we aimed to review the data on thyroid ultrasound elastography.

Application of Sonoelastography in Differential Diagnosis of Benign and Malignant Thyroid Nodules

Background:

Sonoelastography is a new ultrasound method which could be helpful to determine which thyroid nodule is malignant. We designed this study to evaluate the accuracy of sonoelastography in differentiating of benign and malignant thyroid nodules in Iranian patients.

Methods:

Forty thyroid nodules in forty consecutive patients who had been referred for sonography-guided fine-needle aspiration biopsy were evaluated. Gray scale ultrasound and elastosonography by real-time, freehand technique applied for all patients. Elastography findings were classified into four groups. Nodules which were classified as patterns 1 or 2 in elastogram evaluation were classified as benign and probably malignant if elastogram scans were patterns 3 and 4 of elastogram scan.

Results:

Mean age ± standard deviation (SD) was 42.2 ± 12.6 years, and mean ± SD thyroid-stimulating hormone level was 1.4 ± 1.9 IU/ml. Thirty-five cases (87.5%) were female and 5 (12.5%) were male. Histological examination indicated 27 (67.5%) benign and 13 (32.5%) malignant nodules. The most elastogram score was 2 (50%) followed by score 3. The cut-off point of 2 considered as the best value to differentiate benign and malignant thyroid nodules with sensitivity and specificity of 61% and 78% (area under the curve = 0.76, 95% confidence interval: 0.6–0.92, P = 0.007).

Conclusions:

Sonoelastography could help to differentiate benign and malignant thyroid nodules. As our sample size was limited, larger studies are recommended.

Comparison of Diagnostic Accuracy of Real-Time Elastography and Shear Wave Elastography in Differentiation Malignant From Benign Thyroid Nodules

Thyroid nodules are relatively more prevalent in iodine-deficiency area, and the incidence increased sharply in the past decade in these areas. Workup of malignant from benign nodules in clinic was the main problem for managing thyroid nodules.An overall search for the articles about the diagnostic performance of real-time elastography (RTE) and shear wave elastography (SWE) before April 2015 in the databases of PubMed, Embase, and Google scholar. The pooled sensitivity, specificity, and summary receiver operating characteristic (SROC) curve were obtained from individual studies with a random-effects model. Subgroup and meta-regression analysis were also performed.Fifty-six studies involved in 2621 malignant nodules and 7380 benign nodules were contained in our meta-analysis. The pooled sensitivity and specificity of RTE was 83.0% and 81.2%, which is higher than SWE (sensitivity: 78.7%, specificity: 80.5%). The areas under the SROC curve of RTE and SWE were 0.885 and 0.842 respectively. RTE had higher diagnostic value for Caucasians than Asians. Stran ratio (SR) assessment had higher diagnostic performance than elasticity score (ES) system. Similarly, it had higher diagnostic value when malignant nodules were more than 50.In summary, the results revealed that RTE had higher diagnostic performance than SWE in differentiating malignant from benign nodules. However, future international multicenter studies in the region of thyroid risk need to further assess the diagnostic performance of RTE.

Ultrasound scoring in combination with ultrasound elastography for differentiating benign and malignant thyroid nodules

OBJECTIVE

The aim of this study was to evaluate the value of ultrasound scores obtained by conventional ultrasonography and ultrasound elastography in the differentiation of benign and malignant thyroid nodules in Chinese patients.

METHODS

This study included 297 patients who were referred for surgery for compressive symptoms or suspicion of malignancy. Five hundred and twelve thyroid nodules were examined by ultrasonography. The final diagnosis was based on histological findings. A seven-point ultrasound scoring system based on conventional ultrasonography and a five-point scoring system based on ultrasound elastography were applied independently or in combination. The receiver operating characteristic (ROC) curves were graphed, and the areas under the curves (AUCs) were compared using the χ(2) -test.

RESULTS

Solid composition, hypo-echoic appearance, an irregular or blurred margin, an aspect ratio ≥1, intranodular blood flow and presence of microcalcifications were significant predictors of malignant thyroid nodules. The AUC (95% CI) was 0·9067 (0·8817-0·9318) for the ultrasound scores based on conventional ultrasonography and 0·9080 (0·8842-0·9317) for the elasticity scores. The combination of these two scoring systems provided good accuracy with an AUC (95% CI) of 0·9415 (0·9223-0·9606), which was significantly higher than that obtained with the conventional ultrasound scores (χ(2)  = 36·03, P < 0·001) or the elasticity scores (χ(2)  = 12·80, P < 0·001) individually. When we set the cut-point to ≥5, the sensitivity and specificity were 85·22% and 87·38%, respectively.

CONCLUSIONS

Elastography in combination with conventional ultrasonography is a promising imaging-based approach that can assist in the differential diagnosis of thyroid cancer.

Elastography in the differential diagnosis of thyroid nodules

Despite the publication of a recent meta-analysis of elastography in thyroid nodules, further work is necessary on this issue in different populations. In this study, we aimed to evaluate the clinical value of elastography on nodular goiters in mild iodine-deficient regions without excluding patients according to nodule characteristics. This prospective study was conducted between April 2010 and December 2011 in Yıldırım Beyazıt Dıskapı Research Hospital Endocrinology outpatient clinic. Five hundred twenty-eight nodular goiter patients who underwent thyroid fine-needle aspiration biopsy were included in our study. Elastography scores and indexes were measured with real-time ultrasound elastography (Hitachi® EUB 7000 HV machine with 13 MHz linear transducer). There were 471 females and 57 males and their ages ranged from 45 years to 78 years. A total of 601 nodules were evaluated in these patients. The area under the curve (AUC) for the elasto score was 0.91 (p < 0.0001) and AUC for the strain index (SI) was 0.96 (p < 0.0001). We suggest that the SI reflects malignancy better than the elasto score. We conclude that elastography scores greater than 3 have 76% sensitivity and 96% specificity for diagnosing malignancy. For SI, we conclude that 3.75 (83% sensitivity and 95% specificity) is the cutoff point. Elasto score and SI measurements of thyroid nodules in our population are efficient and increase the diagnostic performance of the sonography.

Diagnostic performance of elastography in cytologically indeterminate thyroid nodules

Cytological examination of material from fine-needle aspiration biopsy is the mainstay of diagnosis of thyroid nodules, thanks to its remarkable accuracy and scarcity of complications. However, follicular lesions (also called indeterminate lesions or Thy3 in the current classification), a heterogeneous group of lesions in which cytology is unable to give a definitive diagnosis to, represent its main limit. Elastography has been proposed as a potential diagnostic tool to define the risk of malignancy in the aforementioned nodules, but at present there is no conclusive data due to the small number of specifically addressed studies and the lack of concordance among them. The objective of our study was to evaluate the role of real-time elastography (RTE) for refining diagnosis of Thy3 nodules, by integrating diagnostic information provided by traditional ultrasound (US). The study included 108 patients with Thy3 nodules awaiting for surgery, which were evaluated by US (considering hypoecogenicity, irregular margins, microcalcifications, halo sign, and intranodular vascularization) and RTE. Nodules were classified at RTE using a four-class color scale. At histologic examination, 75 nodules were benign and 33 malignant. As expected, none of the ultrasound parameters alone was adequate in predicting malignancy or benignity of the nodules; in the presence of at least two US risk factors, we obtained 61 % sensitivity, 83 % specificity, and 77 % accuracy with 6.8 OR (95 % CI 2.4-20.4). RTE scores 3 and 4 showed 76 % sensitivity, 88 % specificity, 74 % PPV, and 89 % NPV with diagnostic accuracy of 84 %; the data are statistically significant (p < 0.0001) with a OR of 21.9 (95 % CI 7.1-76). By combining RTE with US parameters, the presence of at least 2 characters of suspicion had 88 % sensitivity and 94 % NPV with 23.8 OR (95 % CI 7-106.3). The use of combined RTE and US leads to the identification of two patients subpopulations which have a significantly different malignancy risk (6 vs. 63 %); further studies are needed to verify if it is possible to send only the first group to thyroidectomy and the other to follow-up.

Thyroid ultrasound features and risk of carcinoma: a systematic review and meta-analysis of observational studies

BACKGROUND

Thyroid nodules are a common finding in the general population, and their detection is increasing with the widespread use of ultrasound (US). Thyroid cancer is found in 5-15% of cases depending on sex, age, and exposure to other risk factors. Some US parameters have been associated with increased risk of malignancy. However, no characteristic seems sufficiently reliable in isolation to diagnose malignancy. The objective of this meta-analysis was to evaluate the diagnostic performance of US features for thyroid malignancy in patients with unselected thyroid nodules and nodules with indeterminate fine-needle aspiration (FNA) cytology.

METHODS

Electronic databases were reviewed for studies published prior to July 2012 that evaluated US features of thyroid nodules and reported postoperative histopathologic diagnosis. A manual search of references of review and key articles, and previous meta-analyses was also performed. A separate meta-analysis was performed including only nodules with indeterminate cytology. Analyzed features were solid structure, hypoechogenicity, irregular margins, absence of halo, microcalcifications, central vascularization, solitary nodule, heterogeneity, taller than wide shape, and absence of elasticity.

RESULTS

Fifty-two observational studies (12,786 nodules) were included. Nine studies included nodules with indeterminate cytology as a separate category, comprising 1851 nodules. In unselected nodules, all US features were significantly associated with malignancy with an odds ratio varying from 1.78 to 35.7, and microcalcifications, irregular margins, and a taller than wide shape had high specificities (Sp; 87.8%, 83.1%, 96.6%) and positive likelihood ratios (LHR; 3.26, 2.99, 8.07). Absence of elasticity was the single feature with the best diagnostic performance (sensitivity 87.9%, Sp 86.2%, and positive LHR 6.39). The presence of central vascularization was the most specific US feature in nodules with indeterminate cytology (Sp 96% and positive LHR 2.13).

CONCLUSIONS

US features in isolation do not provide reliable information to select nodules that should have a FNA performed. A combination of US characteristics with higher likelihood ratios and consequently with higher post-test probabilities of malignancy-microcalcifications, or a taller than wide shape, or irregular margins, or absence of elasticity-will probably identify nodules with an increased risk for malignancy. Further studies are required to standardize elastography techniques and evaluate outcomes, especially in nodules with an indeterminate cytology.

Strain US Elastography for the Characterization of Thyroid Nodules: Advantages and Limitation

Thyroid nodules, with their high prevalence in the general population, represent a diagnostic challenge for clinicians. Ultrasound (US), although absolutely reliable in detecting thyroid nodules, is still not accurate enough to differentiate them into benign and malignant. A promising novel modality, US elastography, has been introduced in order to further increase US accuracy. The purpose of this review article is to assess the thyroid application of US strain elastography, also known as real-time elastography or quasistatic elastography. We provide a presentation of the technique, and of up-to-date literature, analyzing the most prominent results reported for thyroid nodules differentiation. The practical advantages and limitations of strain elastography are extensively discussed herein.

The value of real-time ultrasound elastography in chronic autoimmune thyroiditis

OBJECTIVE

Chronic autoimmune thyroiditis (CAT) (chronic lymphocytic thyroiditis-Hashimoto's thyroiditis), which is the most common inflammatory disorder of the thyroid gland, causes hypothyroidism. Ultrasound elastography is a newly developed sonographic technique that provides an estimation of tissue elasticity by measuring the degree of tissue displacement under the application of an external force. In this study, our aim was to evaluate the accuracy of strain index ratio with real-time ultrasound elastography and to calculate the cut-off point for the diagnosis of CAT. Our aim was also to lead further studies on other pathological changes such as lymphoma, malign nodules etc. based on CAT by using this cut-off point. The gains from this study and further studies will assist clinical diagnoses and follow-up.

METHODS

Aplio™ 500 ultrasound machine (Toshiba Medical Systems Co. Ltd, Otawara, Japan) with linear 4.8-11.0 MHz transducers and elastography software was used. Routine B-mode (dimensions and parenchymal echogenicity) ultrasound evaluation was performed prior to the ultrasound elastography.

RESULTS

A total of 31 randomized patients (3 males, 28 females) with a mean age of 39.13 ± 10.16 years (range, 16-58 years) with CAT and 21 healthy controls (6 males, 15 females) with mean age of 34.67 ± 16.31 years (range, 14-81 years) were prospectively examined. The mean values of thyroid-stimulating hormone (TSH; normal TSH value is 0.27-4.20 IU ml(-1)) and anti-thyroid peroxidase (anti-TPO; normal anti-TPO value is 0-34 IU ml(-1)) were 3.40 ± 2.70 and 373.66 ± 148.94 IU ml(-1), respectively. No correlation was detected between serum TSH and thyroid tissue strain index (Spearman r coefficient of TSH was -0.290). Positive-sided correlation was detected between anti-TPO values and thyroid tissue strain index ratio (Spearman r coefficient of anti-TPO was 0.682). The median strain index ratio of patients with CAT (1.39 ± 0.72) was significantly higher than the mean ratio of the controls (0.76 ± 0.55). The area under the receiver operating characteristic curve was 0.775 (95% confidence interval). The optimal cut-off value (in which the sum of sensitivity and specificity was highest) for the prediction of diffuse thyroid pathology was 0.677. For this cut-off ratio, thyroid stiffness had 96% sensitivity and 67% specificity. A total of 30 of 31 patients (96%) and a total of 7 of 21 healthy controls (33%) exceeded the cut-off points.

CONCLUSION

The strain index ratio was higher in CAT than in normal thyroid parenchyma in real-time ultrasound elastography. Thus, it seems to be a useful method for the assessment of CAT with real-time ultrasound elastography, and further studies assessing the correlation of sonoelastography findings and histopathological subtypes of CAT would enrich the findings of the present study.

ADVANCES IN KNOWLEDGE

In our study, we detected the stiffness ratio of the thyroid tissue in patients with CAT. The cut-off value should be helpful for diagnosis or follow-up of the recently developed lesions such as lymphoma, malign nodule, etc. based on CAT. This study should also encourage new studies about CAT and ultrasound elastography.

Correlation between semiquantitative sonoelastography and immunohistochemistry in the evaluation of testicular focal lesions

BACKGROUND

Sonoelastography is a novel and promising imaging tool, which has been applied to breast, thyroid, and prostate tissues. The aim of this study was to evaluate focal lesions of the testes with diameters of <10 mm using sonoelastography, B-mode sonography (US), and colour Doppler ultrasonography (CDU).

METHODS

Thirty patients who were referred to our outpatient clinics for varicocoeles, scrotal pain, scrotal enlargements, epididymitis, palpable testicular nodules, or infertility, were prospectively enrolled into this study. Ultrasound evaluations had revealed that 27 subjects had focal testicular lesions with diameters of <10 mm and 3 subjects had 10-mm spherical non-homogeneous testicular nodules. All lesions were evaluated using semiquantitative sonoelastography, and the patients underwent orchifunicolectomies. The testicular lesions were examined histopathologically. The vascularization of the lesions and the surrounding testicular parenchyma was evaluated by analysing the immunohistochemical distribution of the cluster of differentiation 31 and by calculating the vascular indices (VI). Potential associations between the strain ratios (stiffness of the lesions) and the VI were tested.

RESULTS

Analyses of the strain fields obtained using semiquantitative sonoelastography yielded different values for the masses and the surrounding tissues, which led to significant increases in the strain ratios. Sonoelastography upheld all of the diagnoses that were suspected when the patients were physically examined, when the serum markers were analysed, and after the patients had undergone US and CDU. Histopathological examinations confirmed the neoplastic characteristics of these masses. A significant inverse correlation was determined between the sonoelastographic strain ratio and the VI (Pearson correlation coefficient, r, = - 0.93; P < 0.001).

CONCLUSION

Our investigation shows that semiquantitative sonoelastography may provide additional objective information to support the algorithm used to diagnose testicular lesions. This might be of crucial diagnostic importance for lesions with diameters of <10 mm, particularly if they are not palpable, are negative for serum tumour markers, and if the findings from ultrasonography and CDU are equivocal. The findings from semiquantitative sonoelastography might indicate the need for surgical exploration. Further investigations with larger numbers of patients are required to corroborate these data and to support the use of semiquantitative sonoelastography in the evaluation of testicular lesions.

Malignancy rate of thyroid nodules defined as follicular lesion of undetermined significance and atypia of undetermined significance in thyroid cytopathology and its relation with ultrasonographic features

Fine-needle aspiration biopsy (FNAB) has been widely accepted as the most accurate, safe, and cost-effective method for evaluation of thyroid nodules. The most challenging category in FNAB is atypia of undetermined significance (AUS) and follicular lesion of undetermined significance (FLUS). The Bethesda system (BS) recommends repeat FNAB in that category due to its low risk of malignancy. In our study, we aimed to investigate the malignancy rate of thyroid nodules of AUS and FLUS and whether there were different malignancy rates among the different patterns in this category, and to evaluate the presence of biochemical, clinical, and echographic features possibly predictive of malignancy related to AUS and FLUS. Data of 268 patients operated for AUS and FLUS cytology were screened retrospectively. Ultrasonographic features and thyroid function tests, thyroid antibodies, scintigraphy, and histopathological results were evaluated. Of the 268 patients' results, 276 nodules are evaluated. Malignancy rates were 24.3 % in the AUS group, 19.8 % in the FLUS group, and 22.8 % in both groups. In the evaluation of all nodules, the predictive features of malignancy are hypoechogenicity and peripheral vascularization of the nodule. We determined that the malignancy rates in these nodules are higher than that in the literature rate. This high ratio may be due to the fact that we studied only patients who underwent surgery. The ultrasonographic features alone may be insufficient to predict the malignancy; therefore, all the clinical and ultrasonographic features must be considered in the evaluation of the thyroid nodules. In addition, we think that the recommended management of repeat FNAB in these groups must be reconsidered with the clinical and ultrasonographic features.

Diagnostic role of ultrasound and elastosonography in nodular goiter

Among several ultrasound patterns, thyroid nodule hypoechogenicity, spot microcalcifications, and an absent halo sign are used for predicting increased risk of thyroid malignancy. The predictive value of ultrasound, however, increases at the expense of its sensitivity, and malignancy is predicted with high specificity only when multiple ultrasound features are simultaneously present. Ultrasound features are important in determining the strength of the indication for carrying out fine needle aspiration. To this end, a system for standardization of ultrasound features (Thyroid Imaging Reporting and Data System) aids in establishing risk of malignancy. Ultrasound elastosonography is a technique that assesses hardness as an indicator of malignancy risk. It has been carried out in selected studies of patients with thyroid nodules, and has been shown to have a high predictive value for malignancy, which is also maintained in cytologically indeterminate and non-diagnostic nodules. Although conventional ultrasound maintains its pivotal role in defining which nodules are candidates for ultrasound elastosonography characterization, the latter seems to have considerable potential in the diagnosis, or exclusion, of thyroid cancer. This especially concerns thyroid nodules with indeterminate cytology at fine-needle aspiration.

Diagnostic performance of ultrasound and ultrasound elastography with respect to physician experience

The aim of this study was to compare the diagnostic performance of gray-scale ultrasound (US), elastography and a combination of gray-scale ultrasound and elastography (US-E) in differentiating benign and malignant thyroid nodules with respect to the level of physician experience. Three hundred fifty-eight patients with 367 thyroid nodules who underwent both gray-scale US and elastography, from November 2011 to January 2012, were included in this study. The diagnostic performance of US performed by experienced and less experienced physicians was compared. Comparisons of the diagnostic performance of US, elastography and US-E were evaluated for each group separately. Of 367 nodules, 121 were malignant and 246 were benign. When we compared the diagnostic performance of the experienced and less experienced physician groups, specificity was statistically higher in the experienced physician group for both US alone (p = 0.001) and US-E (p = 0.048). However, the experienced and less experienced physician groups did not differ significantly on other measures of diagnostic performance, regardless of modality. For the experienced physicians, the specificity and positive predictive value US were 88.0% and 76.8%, respectively; both of them were significantly higher than the corresponding values for US-E. For the less experienced physicians, specificity was significantly higher on elastography (93.8%) than on US (71.4%) (p < 0.001). However, diagnostic performance did not differ significantly between US and US-E for the less experienced physicians. Experienced physicians had superior specificity compared with less experienced physicians. The diagnostic performance of elastography and US-E was inferior compared with that of US alone, irrespective of the level of experience of the physician.

The frequency of malignancy and the relationship between malignancy and ultrasonographic features of thyroid nodules with indeterminate cytology

Various approaches are available for the management of nodules that are evaluated to be indeterminate according to the results of thyroid fine needle aspiration biopsy. The present study aimed to determine the rate of malignancy and the ultrasonographic features that could be used as predictor of malignant pathologies at the nodules with indeterminate cytology. A total of 201 patients who underwent total thyroidectomy and whose fine needle aspiration biopsy results were evaluated to be Hurthle cell lesion (n = 99), follicular neoplasm (n = 61) and [corrected] suspicious for malignancy (n = 41) were enrolled in this study. Of these patients, 178 were females (88.6 %) and 23 were males (11.4 %). The rates of malignancy were found to be 33.3 % in the Hurthle cell lesion group, 23.0 % in the follicular neoplasm group and 53.7 % in the suspicious for malignancy group (p = 0.006). The comparison of the ultrasonographic characteristics of the malignant and benign nodules revealed hypoechogenicity and microcalcification to be more common in malignant nodules (34.3 vs. 16.9 %, p = 0.005; 27.1 vs. 13.1 %, p = 0.014; respectively). While 92.3 % of the malignant nodules were ≥1 cm, 82.9 % of the benign nodules were ≥1 cm (p = 0.042). We believe that as the patients at Hurthle cell lesion group have higher risk of malignancy than the patients with Follicular Neoplasia so total thyroidectomy will be suitable for these patients. [corrected]. In addition, microcalcification and hypoechoic nodules at patients with indeterminate cytology can be related with increased risk of malignancy. [corrected].

Elastosonographic strain index in thyroid nodules with atypia of undetermined significance

AIM

In this study, we aimed to evaluate the diagnostic accuracy of elastosonography (ESG) scoring and strain ratio in patients who had atypia of undetermined significance (AUS) cytology and underwent surgery for thyroid nodules.

MATERIALS AND METHODS

250 patients were included in this study. They had at least one nodule in thyroid USG, underwent USG-guided FNAC according to the current guidelines and had AUS cytology according to the Bethesda system. Both elastosonographic color scoring and strain index were evaluated.

RESULTS

A total of 270 nodules in 250 patients were evaluated. Histopathologically, 81 (30 %) nodules were malignant and 189 (70 %) were benign. According to the ESG, 10 (3.7 %) nodules were assigned a score of 1, while 13 (4.8 %) nodules were assigned a score of 5. All of the nodules with an ESG score of 1 were histopathologically benign and 92.3 % of the patients with ESG score 5 were in the malignant group. Median SI in the benign histopathologic group was significantly lower compared to malignant group [(2.58 (IQR = 2.35) vs. 14.54 (IQR = 10.71)]. The optimal SI cut-off value to distinguish between the benign and malignant nodules was 6.66, with a sensitivity of 98.77 % and specificity of 96.30 %.

CONCLUSION

Our study is one of the first studies evaluating the role of SI for discriminating malignant and benign nodules with AUS cytology. Malignant nodules had a significantly higher stiffness compared to benign ones and SI had high sensitivity, specificity, positive predictive value, negative predictive value and accuracy for these nodules. We think SI may be helpful for the presurgical selection of nodules with AUS cytology.

Comparison of elastographic strain index and thyroid fine-needle aspiration cytology in 631 thyroid nodules

CONTEXT

Ultrasound (US) elastography (USE) was recently been reported as a sensitive, noninvasive tool for identifying thyroid cancer. However, the accuracy of this technique is hampered by the intra- and interoperator variability, some US features of the nodule, and the coexistence of autoimmune thyroid disease (ATD).

OBJECTIVES

The purpose of this article was to assess the accuracy of USE findings in the differential diagnosis of thyroid nodules compared with other US features to evaluate its feasibility in the presence of ATDs and identify the strain index (SI) cutoff with the highest diagnostic performance.

DESIGN

We evaluated 528 consecutive patients for a total of 661 thyroid nodules. All nodules underwent fine-needle aspiration cytology (FNAC) and USE evaluation. The SI was calculated as a ratio of the nodule strain divided by the strain of the softest part of the surrounding normal tissue.

RESULTS

The median SI value was significantly higher in THY4 and THY5 than in THY2 nodules in ATD-positive, ATD-negative, and ATD-unknown patients. The cutoff of SI for malignancy was estimated to be 2.905 by receiver operating characteristic curve analysis in a screening set (379 FNAC results), and then tested in a replication set (252 FNAC results). In all cases, a SI value of ≥ 2.905 conferred to the nodule a significantly greater probability of being malignant. This SI cutoff had the greatest area under the curve, sensitivity, and negative predictive value, compared with the conventional US features of malignancy.

CONCLUSION

The elastographic SI has a high sensitivity, specificity, and negative predictive value for the diagnosis of thyroid malignancy both in the presence and in the absence of ATD. If our data on USE are also confirmed in THY3 nodules, FNAC could be avoided in a number of thyroid nodules with certain features.

Is there a real diagnostic impact of elastosonography and contrast-enhanced ultrasonography in the management of thyroid nodules?

Ultrasonography (US) and the new applications US elastography (USE) and contrast-enhanced US (CEUS) are used in the screening of thyroid nodules, for which fine-needle aspiration biopsy (FNAB) is the best single diagnostic test. The aim of the study was to compare the sensitivity, specificity, positive predictive value (PPV), and accuracy of the four examinations in nodules with cytological and histological diagnoses. The study used data from US, FNAB, USE (elasticity (ELX 2/1) index), and CEUS (Peak index and time to peak (TTP) index) evaluated in 73 thyroid nodules in 63 consecutive patients likely to undergo surgery. Cytological-histological correlation was available for 38 nodules. No correlation emerged between nodule size and cytological results. A significant (P=0.03) positive correlation between cumulative US findings and cytological results was found. In addition, significant correlations between cumulative US findings and cytology (P=0.02) and between cumulative US findings and histology (P<0.0001) were found. US showed the best specificity and PPV, and FNAB the best sensitivity. There was no significant difference in the ELX 2/1 index, Peak index, or TTP index among nodules subdivided according to cytological scores. No significant correlation was found between ELX 2/1 index, Peak index, and TTP index, on the one hand, and nodule size, US cumulative findings, cytology, and histology on the other hand. The sensitivity of the ELX 2/1 index was high, but its specificity was very low. The accuracy and PPV of USE were lower than those of the other procedures. Only the correlation between Peak index and cumulative US findings reached a value close to significance. Our ultimate aim is to minimise unnecessary thyroidectomy. US and FNAB continue to play a central diagnostic role. The use of a US score showed high specificity and PPV. The specificity of FNAB was low in this selected series because of the numbers of indeterminate cytological responses. USE and CEUS are innovative techniques that need to be standardized. The ELX 2/1 index, Peak index, and TTP index seem to be unrelated to histology. The best statistical data on USE and CEUS concerned their sensitivity and PPV, respectively. At present, USE and CEUS are too time-consuming and of limited utility in selecting patients for surgery.

Ultrasound elastography in the head and neck. Part II. Accuracy for malignancy

Ultrasound elastography (USE) describes a variety of ultrasound-based imaging techniques that measure tissue stiffness properties, and is currently under intense investigation for tissue characterization in several anatomic sites. This article summarizes the evidence regarding the accuracy of USE for malignancy in the head and neck. Currently, most published data pertains to small pilot studies with varied methodologies. Encouragingly, most studies have documented promising results for USE in terms of high accuracy for malignancy in thyroid nodules and cervical lymph nodes, which have surpassed conventional sonographic criteria. However, a minority of studies have documented opposite findings. USE seems to be suboptimal for salivary malignancies, and some evidence suggests that USE does not provide useful diagnostic information compared with conventional ultrasonography for miscellaneous neck masses. Further larger studies are required to validate these findings although, in view of the predominance of highly optimistic results for thyroid nodules and cervical lymph nodes, USE may become a useful ancillary technique in the routine diagnostic work-up of lesions in these tissues in the near future.

Prospective evaluation in 123 patients of strain ratio as provided by quantitative elastosonography and multiparametric ultrasound evaluation (ultrasound score) for the characterisation of thyroid nodules

PURPOSE

This study was done to compare quantitative elastosonography and ultrasound analysis in the characterisation of thyroid nodules.

MATERIALS AND METHODS

From July 2009 to September 2011, 123 patients with 147 thyroid nodules were included in our study. All patients enrolled had to undergo thyroidectomy because of nodular thyroid disease (goitre or nodules). After preliminary examination with conventional ultrasound (US) and colour Doppler US, the patients were examined with elastosonography, using high-level equipment (Toshiba Aplio XG) and quantitative software (Elasto-Q). Each lesion was characterised using an US score (echogenicity, borders, microcalcifications and colour Doppler pattern), and then by elastosonographic strain ratio. Each patient subsequently underwent thyroidectomy. Histological results were used as the gold standard.

RESULTS

Histological examination demonstrated 89 benign and 58 malignant lesions. On average, the strain ratio value was 2.84±2.69 (range, 0.05-14.5; p=0.001). Sensitivity and specificity of the US score were about 56% and 72%, respectively, whereas those of the strain ratio were 93% and 89%, using a cut-off of 2 obtained with receiver operating characteristic (ROC) curve analysis. Elastosonography was more accurate than US and colour Doppler US in characterising thyroid nodules (p=0.002).

CONCLUSIONS

Quantitative elastosonography is a useful diagnostic tool in the evaluation of thyroid lesions, and can be used to limit fine-needle aspiration cytology and improve the selection of patients for thyroidectomy.

Thin core biopsy should help to discriminate thyroid nodules cytologically classified as indeterminate. A new sampling technique

Indeterminate neoplasms (IN) represent the gray zone of thyroid cytology in which malignant and benign tumors cannot be discriminated. Recently, the approach by thin core needle biopsy has been proposed. Here we report a new thin core needle biopsy approach in 40 consecutive patients with thyroid IN at cytology. In this study, a 21-G needle was inserted into the nodule, advanced within the lesion, and moved ahead reaching extranodular tissue. The resulting sample allowed to evaluate the cytomorphology of nodular tissue, its relationship with extranodular parenchyma, and the nodule's capsule when present. All biopsies were adequate for diagnosis but one. Of the 39 adequate samples, 5 cases were papillary cancer as confirmed at histology, while 14 nodules avoided surgery because of Hürthle cell hyperplasia in thyroiditis (n = 6) and microfollicular adenomatous hyperplasia (n = 8). The remaining 20 cases were assessed as follicular neoplasms because of encapsulation and were evaluated by immunohistochemistry. Of these, 6 had positive markers in different degree and 1/6 has follicular cancer at histology, while the other 14 were benign after surgery. Overall, this approach by thin core needle biopsy identified benignancy in 14/40 (35 %) IN avoiding surgery. As a conclusion, thin core biopsy should help to discern the nature of thyroid lesions cytologically classified as indeterminate, and it should be used as a complementary test in thyroid nodule assessment.

Q-elastography in the presurgical diagnosis of thyroid nodules with indeterminate cytology

Quantitative ultrasound (US) elastography (Q-USE), able to evaluate tissue stiffness has been indicated as a new diagnostic tool to differentiate benign from malignant thyroid lesions. Aim of this prospective study, conducted at the Department of Surgical Sciences, of the “Sapienza” University of Rome, was to evaluate the diagnostic accuracy of Q-USE, compared with US parameters, in thyroid nodules with indeterminate cytology (Thy3).The case study included 140 nodules from 140 consecutive patients. Patient’s thyroid nodules were evaluated by Q-USE, measuring the strain ratio (SR) of stiffness between nodular and surrounding normal thyroid tissue, and conventional US parameters prior fine-needle aspiration cytology. Those with Thy3 diagnosis were included in the study. Forty of the nodules analyzed harbored a malignant lesion. Q-USE demonstrated that malignant nodules have a significant higher stiffness with respect to benign one and an optimun SR cut-off value of 2.05 was individuated following ROC analysis. Univariate analysis showed that hypoechogenicity, irregular margins and SR >2.05 associated with malignancy, with an accuracy of 67.2%, 81,0% and 89.8%, respectively. Data were unaffected by nodule size or thyroiditis. These findings were confirmed in multivariate analysis demonstrating a significant association of the SR and the irregular margins with thyroid nodule’s malignancy. In conclusion, we demonstrated the diagnostic utility of Q-USE in the differential diagnosis of thyroid nodules with indeterminate cytology that, if confirmed, could be of major clinical utility in patients’ presurgical selection.

Comparison of the diagnostic accuracy of combined elastosonography and BRAF analysis vs cytology and ultrasonography for thyroid nodule suspected of malignancy

OBJECTIVE

Diagnosing thyroid nodules preoperatively using traditional diagnostic tools - ultrasonography (US) and cytology - still carries a considerable degree of uncertainty, and surgery is recommended for a far from negligible number of patients simply for diagnostic purposes. Thyroid elastosonography (USE) and BRAF analysis have recently proved useful in detecting thyroid malignancies. The aim of this study is to establish whether combining USE and BRAF testing ameliorates preoperative diagnosis of thyroid nodule candidates for intervention by conventional approaches, thereby avoiding the need for diagnostic surgical procedures.

DESIGN AND PATIENTS

We retrospectively analysed the files of 155 consecutive patients with 164 nodules, all assessed by ultrasonography, cytology, USE and BRAF testing, who underwent thyroid surgery.

RESULTS

Of the 164 nodules, 74 (45%) were benign and 90 (55%) were malignant at final histology. Combining ultrasonography and cytology identified 21 (13%) as benign, 93 (57%) as malignant or probably malignant and 50 (30%) as 'suspended' (when the combined test was not able to classify the node as benign or malignant) with a 99% sensitivity, 28% specificity, 63% PPV, 95% NPV and 67% accuracy. Combining USE and BRAF testing indicated that 59 (36%) were benign, 74 (45%) were malignant and 31 (19%) were in a 'suspended' category, with a 95% sensitivity, 74% specificity, 82% PPV, 93% NPV and 86% accuracy.

CONCLUSIONS

In assessing thyroid nodules suspected of malignancy, the combined analysis of USE and BRAF is equally sensitive and more specific than conventional procedures, achieving more accurate preoperative diagnoses than US and cytology combined. USE and BRAF analysis for thyroid nodule evaluation might reduce the number of unnecessary surgical procedures.

Ultrasound elastography is not superior to grayscale ultrasound in predicting malignancy in thyroid nodules

BACKGROUND

Several studies have evaluated the ability of ultrasound elastography (USE) to diagnose malignant nodules. However, these studies had important limiting factors, selection bias and small sample size. The aims of the present study were to prospectively assess, in a large group of patients, the diagnostic power of USE for detecting malignancy in thyroid nodules, and to compare this technique with B-mode grayscale ultrasonography (BUS) and power Doppler ultrasonography (PD).

METHOD

There were 194 patients with 237 thyroid nodules who were examined using BUS, PD, and USE. USE scores were classified according to the elasticity: score 1 as high, score 2 as intermediate, and score 3 as low (i.e., a high degree of stiffness). Fine-needle aspiration cytology (FNAC) was performed in all nodules at least two different times. Nodules having two benign FNAC readings that did not change the diameter during a 6-month follow-up period were classified as benign. Patients having thyroid nodules with indeterminate, suspicious, or malignant cytology had total or hemithyroidectomy to remove the nodule and treat the malignancy.

RESULTS

Fifty eight (25%) nodules in 45 (23%) patients were found to be malignant. USE had a limited sensitivity and a positive predictive value in detecting malignant thyroid nodules and was not superior to BUS. USE had almost the same specificity and a negative predictive value as BUS. A power Doppler type-3 pattern was not of sufficient sensitivity to detect malignancies in thyroid nodules.

CONCLUSIONS

In contrast to earlier reports, this current study noted a lower sensitivity and specificity of USE for the diagnosis of malignancy in thyroid nodules than previously reported.

High diagnostic accuracy and interobserver reliability of real-time elastography in the evaluation of thyroid nodules

Elastography is a new diagnostic tool in the evaluation of thyroid nodules. Aim of the study was to evaluate the accuracy and reliability of elastography in discriminating thyroid lesions and the interobserver variability. One hundred thirty-two nodules in 115 patients selected for thyroid surgery underwent conventional ultrasound and elastographic evaluation. Elastography score was divided in four categories (totally elastic nodule, mainly elastic, mainly rigid and totally rigid) according to signal distribution. Three independent operators conducted the study. Final histology showed 92 benign nodules and 40 malignant. On elastography, 77/92 benign nodules were classified as score 1 or 2 and 34/40 malignant nodules as score 3 or 4 (sensitivity 85%, specificity 83.7%, positive predictive value [PPV] 69.3%, negative predictive value [NPV] 92.7%). Rate of concordance between operators was good (K test: 0.64, p < 0.0001). Simple to use, with good interobserver agreement, elastography has all the requisites to become an important complement of conventional US examination in the near future.