Malignancy rate in sonographically suspicious thyroid nodules of less than a centimeter in size does not decrease with decreasing size

Accuracy of shear wave elastography in characterization of thyroid nodules in children and adolescents

BACKGROUND

Thyroid nodules are an important health problem in children and adolescents. They possess a higher risk of malignancy in comparison to adults. This fact forms a great dilemma for clinicians. The aim of this study was to evaluate the reliability of shear wave elastography (SWE) as a non-invasive technique in the characterization of thyroid nodules in children and adolescents.

METHODS

This prospective study included 56 patients with thyroid nodules. All the patients underwent clinical assessment, laboratory investigations, ultrasound, and Doppler examination, followed by an SWE assessment. Statistical analysis was performed and the best cut-off value to differentiate benign from malignant nodules was determined using the ROC curve and AUC.

RESULTS

Seventy-two nodules were detected in the examined patients (ages ranged from 11 to 19 years, with mean age of 14.89 ± 2.3 years). Fifty-eight nodules (80.6%) were benign, and fourteen nodules (19.4%) were malignant (histopathologically proved). Highly suspicious criteria for prediction of malignancy by ultrasound and Doppler were hypoechoic echopattern, internal or internal and peripheral vascularity, microcalcifications, taller-than-wide dimensions, irregular outlines, and absence of halo (p < 0.05). The diagnostic performance for their summation was 70.69% sensitivity, 82.8% specificity, 80.45% accuracy, a 63.79% positive predictive value (PPV), and 87.9% negative predictive values (NPV). Regarding SWE, our results showed that 42.2 kPa was the best cut-off value, with AUC = 0.921 to differentiate malignant from benign nodules; the diagnostic performance was 85.71% sensitivity, 94.83% specificity, 93.06% accuracy, 76.9% PPV, and 93.2% NPV.

CONCLUSION

Shear wave elastography is a non-invasive technique that can assist in the diagnosis of malignant thyroid nodules among children and adolescents.

The Role of Cytology in the Diagnosis of Subcentimeter Thyroid Lesions

Thyroid nodules are common and typically detected by palpation and/or ultrasound (US). Guidelines have defined the management of large nodules, but controversy exists regarding nodules ≤ 1 cm. We evaluated a cohort of patients with subcentimeter nodules to determine their rate of malignancy (ROM). A total of 475 thyroid FNAs of lesions ≤ 1 cm with available follow-up were identified from January 2015–December 2019. For comparative analysis, we added a control series of 606 thyroid lesions larger than 1 cm from the same reference period. All aspirates were processed with liquid-based cytology and classified according to The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC). Subcentimeter nodules were stratified as 35 category I—non-diagnostic cases (ND; 7.3%), 144 category II—benign lesions (BL; 30.3%), 12 category III—atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS; 2.5%), 12 category IV—follicular neoplasm/suspicious for follicular neoplasm (FN/SFN; 2.5%), 124 category V—suspicious for malignancy (SM; 26.1%), and 148 category VI—positive for malignancy (PM; 31.1%). A total of 307 cases (64.6%) underwent subsequent surgery. Only one ND and three BLs had a malignant outcome. ROM for indeterminate lesions (III + IV) was 3.2%; with 1.6% for category III and 3.2% for category IV. ROM for the malignant categories (V + VI) was 88.2%. The control cohort of lesions demonstrated a higher number of benign histological diagnoses (67.3%). We documented that 57.2% of suspected subcentimeter lesions were malignant, with a minor proportion that belonged in indeterminate categories. There were very few ND samples, suggesting that aspirates of subcentimeter lesions yield satisfactory results. Suspected US features in subcentimeter lesions should be evaluated and followed by an interdisciplinary team for appropriate patient management.

Contrast-enhanced ultrasound: a valuable modality for extracapsular extension assessment in papillary thyroid cancer

OBJECTIVES

To evaluate the diagnostic accuracy of preoperative contrast-enhanced ultrasound (CEUS) to detect extracapsular extension (ECE) and identify the relationship between ECE and nodule enhancement patterns in patients with papillary thyroid cancer (PTC).

METHODS

Patients with suspected thyroid cancer underwent ultrasound (US) and CEUS examinations. The US and CEUS features of the PTC nodules and thyroid capsule were recorded and classified individually. The accuracy of US and CEUS in detecting ECE was compared individually, and its relationship with various tumour enhancement patterns was analysed. The presence or absence of ECE and cervical lymph node metastasis (LNM) was confirmed pathologically.

RESULTS

The final dataset included 119 patients with 124 PTC nodules. Seventy-two (60.5%) of these patients with PTC had no ECE (including 38 patients with single capsule invasion), while the remaining 52 had ECE. A significant difference was found in nodules with non-capsule invasion, single capsule invasion, and ECE between the cervical LNM and non-LNM groups (p < 0.01). Receiver operating characteristic curve analysis demonstrated that area under the curve (AUC) of ECE for cervical LNM was higher than that of capsule invasion (71.9% vs. 49.6%). Moreover, the CEUS images acquired to detect ECE showed higher AUC values than those of US images (79.4% vs. 65.8%) (p = 0.02). Among the PTC nodules with differential enhancement, hyper-enhanced nodules had the highest incidence of capsule invasion (41.9%), while hypo-enhanced ones had a higher incidence of ECE (47.4%).

CONCLUSIONS

Compared with conventional US, CEUS is a more valuable and non-invasive imaging modality to detect ECE.

KEY POINTS

• Single capsular invasion was a poor predictor of cervical lymph node metastasis, while extracapsular extension assessments were clinically significant for predicting cervical lymph node metastasis. • CEUS is better than conventional US in detecting extracapsular extension in papillary thyroid carcinoma (AUC: 79.4% vs. 65.8%) (p = 0.02). • Among the thyroid papillary carcinoma nodules with differential enhancement, hyper-enhanced nodules had the highest incidence of single capsule invasion (41.9%), while hypo-enhanced ones had a higher incidence of ECE (47.4%).

Subcentimetre thyroid nodules: Sonographic features associated with malignancy

Introduction

The aim of this study was to identify the ultrasound features which are associated with malignancy in subcentimetre thyroid nodules.

Methods

This retrospective study included 454 thyroid nodules <10 mm in size in 413 patients from 2012 to 2016, which were subjected to fine needle aspiration cytology. Each nodule was classified according to the ultrasound patterns of the 2015 American Thyroid Association guidelines and the high suspicion ultrasound features (solid, hypo-echogenicity, irregular margins, microcalcifications, taller-than-wide, interrupted rim calcifications, and extrathyroidal extension) were identified for evaluation of their diagnostic performance.

Results

Of the American Thyroid Association high suspicion ultrasound features, univariate analysis showed that hypo-echogenicity (sensitivity 81.6% (95% CI 65.7-92.3%), specificity 50.0% (95% CI 43.4-56.6%)), irregular margins (sensitivity 34.2% (95% CI 19.6-51.4%), specificity 92.2% (95% CI 88.0-95.3%)), microcalcifications (sensitivity 23.7% (95% CI 11.4-40.2%), specificity 91.0% (95% CI 86.5-94.3%)), and taller-than-wide (sensitivity 23.7% (95% CI 11.4-40.2%), specificity 92.2% (95% CI 88.0-95.3%)) were significantly associated with a malignant diagnosis. Amongst the above features, subsequent multivariate analysis identified a combination of hypo-echogenicity and irregular margins as significantly associated with malignancy. Our malignancy rates based on American Thyroid Association ultrasound patterns from benign to high suspicion were 0.0, 8.3, 3.9, 15.7, and 40.4%, respectively. The American Thyroid Association high suspicion ultrasound pattern had a sensitivity of 50.0% (95% CI 33.4-66.7%) and specificity of 84.5% (95% CI 79.2-88.9%).

Conclusion

The presence of both hypo-echogenicity and irregular margins was significantly associated with malignancy in subcentimetre thyroid nodules in our study. Hence, subcentimetre nodules which are hypoechoic with irregular margins may warrant further follow-up.

The Sonographic Findings of Papillary Thyroid Microcarcinomas

The purpose of this research was to compare the sonographic features of papillary thyroid microcarcinomas (micro-PTCs) to those of macro-PTCs. Patients with known PTC were retrospectively reviewed and divided into micro- or macro-PTC groups, according to the largest nodule diameter, ≤10 mm or >10 mm, respectively. Eighty-nine nodules (62 macro-PTCs and 27 micro-PTCs) were evaluated. Contour irregularity was more common in micro-PTCs than macro-PTCs ( P < .05). No significant difference was found in the presence of hypoechogenicity, heterogeneity, microcalcifications, cystic component, and absence of peripheral halo between groups ( P > .05). Internal vascularity was detected in none of the micro-PTCs while being present in 13% of macro-PTCs ( P < .05). Micro-PTCs demonstrated similar sonographic findings as larger PTCs. In micro-PTCs, the presence of irregular contours, in a micro-nodule, should increase suspicion and consideration for biopsy, when clinically indicated. Internal nodular vascularity may not be present in micro-PTCs and therefore not decrease the suspicion of malignancy in the presence of other suspicious sonographic features.

Should we perform fine needle aspiration cytology of subcentimetre thyroid nodules? A retrospective review of local practice

In light of the rising rate of incidentally detected subcentimetre thyroid nodules due to improved surveillance and diagnostic imaging, the decision of whether to perform fine needle aspiration cytology is increasingly pertinent. We aim to assess (1) the sampling adequacy of fine needle aspiration cytology, (2) malignancy rate, (3) thyroidectomy rate and (4) diagnostic accuracy of fine needle aspiration cytology. A total of 245 subcentimetre nodules in 220 patients underwent fine needle aspiration cytology between 2011 and 2014. Medical records were reviewed for cytology results, subsequent management and histopathological results in the event the patient underwent thyroidectomy. Sampling adequacy was calculated as the percentage of diagnostic results (Bethesda II-VI). Malignancy rate was defined as the percentage of Bethesda IV-VI diagnoses. Amongst patients with Bethesda IV-VI diagnoses who underwent thyroidectomy, their cytology reports were correlated with post-operative histopathological findings. The sampling adequacy of fine needle aspiration cytology was 77.1%. Malignancy rate (Bethesda IV-VI) was 9.7%. The respective malignancy rates in the < 5 mm nodule group and ≥ 5 mm nodule group were 6.67 and 10.0%. In total, 79.2% (19/24) of the malignant nodules underwent surgical excision. The rest declined surgery and/or were lost to follow-up. Amongst the malignant nodules which were surgically resected, 84.2% (16/19) had definitive malignant histology. Five of these demonstrated multifocal carcinoma and/or extrathyroidal extension of carcinoma on histology. Initial fine needle aspiration cytology and subsequent histopathological diagnoses matched in all cases except for three that had false-positive fine needle aspiration cytology results. Majority of our patients with suspicious cytology results subsequently underwent thyroidectomy, notwithstanding the relatively lower diagnostic accuracy of fine needle aspiration cytology in subcentimetre thyroid nodules.

Diagnostic value of ultrasound features and sex of fetuses in female patients with papillary thyroid microcarcinoma

Little work has been done on the prediction of papillary thyroid microcarcinoma in female patients who have given birth to children, which may be different from other people. We performed a retrospective review of female patients who underwent thyroidectomy, aiming at identifying special predictors of papillary thyroid microcarcinoma in female patients who have given birth to children. Univariate analysis was used to identify potential covariates for the prediction of papillary thyroid microcarcinoma. Multivariable logistic regression analysis was used to identify independent predictors and construct a regression model based on a training cohort (246 patients) and then the regression model was validated using an independent cohort (80 patients). We found that having not more than one boy, taller-than-wide shape, poorly defined margin, marked hypoechogenicity, and microcalcification were independent risk factors for the papillary thyroid microcarcinoma in multivariate analyses. The combined predictive formula had a high predictive effect for papillary thyroid microcarcinoma (AUC = 0.938 for training cohort and 0.929 for validation cohort, respectively). The combined predictive formula has clinical value in the prognosis of papillary thyroid microcarcinoma and it may be simple and effective to ask fertility condition of patients to increase the US diagnosis accuracy of papillary thyroid microcarcinoma.

Thyroid Papillary Microcarcinoma: Etiology, Clinical Manifestations,Diagnosis, Follow-up, Histopathology and Prognosis

BACKGROUND

Thyroid carcinoma is the most common malignancy of the endocrine system. Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer, accounting for 70-90% of well-differentiated thyroid malignancies. Thyroid papillary microcarcinoma is a subtype of papillary carcinoma that included tumors with less than 10mm diameter. As a result of diagnostic methods improvement, prevalence of this tumor is increasing. In this study we reviewed different characteristics of tumor.

METHODS

We searched various factors about this tumor in different databases (PubMed, Ovid, Google scholar, Iran medex and SID databases, from July 2012 until August 2013), after that, the articles were classified. Data of each article were extracted and sorted in tables. Data of each factor in different articles were summarized.

RESULTS

Etiology, clinical presentation, prognosis, histopathology, follow-up, diagnosis and also age, gender, tumor size and treatment were factors about this tumor described in details here.

CONCLUSION

Awareness and better understanding of the characteristics of this tumor and manage it as an individual and valuable tumor can take an effective step in promoting public health practice.

A taller-than-wide shape is a good predictor of papillary thyroid carcinoma in small solid nodules

OBJECTIVES

The purpose of this study was to evaluate whether a nodule with a taller-than-wide shape (ie, an anteroposterior diameter that is longer than the transverse diameter on a transverse or longitudinal plane [anteroposterior-to-transverse ratio] >1) is a good predictor of papillary thyroid carcinoma (PTC) according to nodule size.

METHODS

We retrospectively examined 207 thyroid nodules in our hospital from September 2011 to February 2013. Nodules were divided into groups by size: small (≤0.5 cm; group A), medium (0.5-1 cm; group B), and large (>1 cm; group C). Sonographic features were defined as an anteroposterior-to-transverse ratio greater than 1, microcalcifications, blurred margins, and hypoechogenicity.

RESULTS

An anteroposterior-to-transverse ratio greater than 1 was the most accurate sonographic feature for predicting PTC in small nodules, with high sensitivity (81.4%) and specificity (96.8%), but it was not accurate in large nodules (>1 cm). Microcalcifications showed higher sensitivity (P< .05) in large nodules (60.0%) than in small ones (27.9%). Hypoechogenicity and blurred margins showed high sensitivity (95.3% and 97.7%, respectively) but low specificity (19.4% and 29.9%) for diagnosis of PTC in small thyroid nodules. An anteroposterior-to-transverse ratio greater than 1 in conjunction with another sonographic feature achieved the highest diagnostic accuracy in small nodules.

CONCLUSIONS

The predictive values of sonographic features depend on nodule size. An anteroposterior-to-transverse ratio greater than 1, especially in conjunction with another sonographic risk factor, showed superior performance for PTC diagnosis in small nodules.

A model to discriminate malignant from benign thyroid nodules using artificial neural network

Objective

This study aimed to construct a model for using in differentiating benign and malignant nodules with the artificial neural network and to increase the objective diagnostic accuracy of US.

Materials and methods

618 consecutive patients (528 women, 161 men) with 689 thyroid nodules (425 malignant and 264 benign nodules) were enrolled in the present study. The presence and absence of each sonographic feature was assessed for each nodule - shape, margin, echogenicity, internal composition, presence of calcifications, peripheral halo and vascularity on color Doppler. The variables meet the following criteria: important sonographic features and statistically significant difference were selected as the input layer to build the ANN for predicting the malignancy of nodules.

Results

Six sonographic features including shape (Taller than wide, p<0.001), margin (Not Well-circumscribed, p<0.001), echogenicity (Hypoechogenicity, p<0.001), internal composition (Solid, p<0.001), presence of calcifications (Microcalcification, p<0.001) and peripheral halo (Absent, p<0.001) were significantly associated with malignant nodules. A three-layer 6-8-1 feed-forward ANN model was built. In the training cohort, the accuracy of the ANN in predicting malignancy of thyroid nodules was 82.3% (AUROC = 0.818), the sensitivity and specificity was 84.5% and 79.1%, respectively. In the validation cohort, the accuracy, sensitivity and specificity was 83.1%, 83.8% and 81.8%, respectively. The AUROC was 0.828.

Conclusion

ANN constructed by sonographic features can discriminate benign and malignant thyroid nodules with high diagnostic accuracy.

Diagnostic accuracy of the ultrasonographic features for subcentimeter thyroid nodules suggested by the revised American Thyroid Association guidelines

BACKGROUND

Recommendations for subcentimeter thyroid nodules that need fine-needle aspiration biopsy are renewed in the revised American Thyroid Association (ATA) guidelines published in 2009. We applied these recommendations to analyze the diagnostic performance of the ATA guidelines and compared it to that of other modified guidelines.

METHODS

We evaluated 1054 nodules with sizes of 6-10 mm in 991 patients. A total of 713 nodules were included in the study population by excluding nodules with insufficient results for deciding whether they had a benign or malignant cytology. Frequencies of ultrasonographic features in benign and malignant nodules were compared, and odds ratios of suspicious ultrasonographic features were obtained with univariate and multivariate analysis. Seven modified guidelines were made based on the revised ATA guidelines and from multivariate analysis results. Diagnostic performances of the guidelines were compared by sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and the area under the receiver operating characteristic curve (Az) value.

RESULTS

In addition to hypoechogenicity, infiltrative margin, microcalcification, and taller-than-wide shape that were suggested by the ATA guidelines, solid composition and macrocalcification were significantly associated with malignancy on multivariate analysis (p=0.001 and 0.003, respectively). Increased vascularity, however, was not significantly associated with malignant nodules (odds ratio 0.729, p=0.212). Among the eight guidelines, the ATA guidelines showed the lowest diagnostic performance (Az=0.616). Excluding increased vascularity and including solid composition with or without macrocalcification to the suspicious ultrasonographic features of the ATA guidelines improved sensitivity (96.6% vs. 97.0%), specificity (26.6% vs. 42.9%), PPV (48.3% vs. 54.7%), and NPV (91.7% vs. 95.2%), thereby resulting in the highest Az value (Az=0.699, p<0.001).

CONCLUSIONS

This study suggests that excluding increased vascularity and adding solid composition to the suspicious ultrasonographic features of the ATA guidelines would significantly improve the diagnostic performance in subcentimeter nodules for the identification of malignant lesions.

Diagnostic performance of combined elastosonography scoring and high-resolution ultrasonography for the differentiation of benign and malignant thyroid nodules

AIM

To evaluate the diagnostic performance of the combined use of elstosonography (USE) scoring and high-resolution ultrasonography (HRUS) for the differentiation of benign and malignant thyroid nodule.

PATIENTS AND METHODS

Forty-seven consecutive patients with 66 thyroid nodules were enrolled in the present study. Thyroid surgery had been already planned for all the patients. All of them were submitted to high-resolution ultrasonography and elastography scoring at the same sitting. The latter was determined with 5-point scoring method. The examination results were compared against pathological findings as the gold standard of reference.

RESULTS

The sensitivity, specificity, accuracy, positive predictive, and negative predictive values of HRUS in the differential diagnosis of thyroid nodules were 92.0%, 72.9%, 60.1%, 95.0%, and 63.1%, respectively, while that of ultrasound elastography scoring were 75.4%, 85.5%, 86.7%, 71.4%, and 90.5%, respectively. Combined use of both US techniques resulted in a higher diagnostic performance as it showed 95.4%, 94.8%, 95.2%, 82.3% and 98.8% sensitivity, specificity, accuracy, positive predictive, and negative predictive values, respectively.

CONCLUSIONS

The use of combined USE and HRS for the differentiation of benign and malignant thyroid nodules resulted in a high diagnostic performance and a significant statistical difference as compared to HRUS or USE alone (P=0.003).