Can increased tumoral vascularity be a quantitative predicting factor of lymph node metastasis in papillary thyroid microcarcinoma?

Ultrasound Combined With FNA-Tg Predicts the Lateral Cervical Lymph Node Metastasis in Papillary Thyroid Carcinoma

OBJECTIVE

The present study analyzed typical ultrasound manifestations and fine-needle aspiration thyroglobulin (FNA-Tg) levels to investigate their association with cervical lymph node metastasis in patients with papillary thyroid carcinoma (PTC).

METHODS

The data of 139 PTC patients with ultrasonically suspected cervical lymph node metastasis treated in our hospital from December 2022 to November 2023 were retrospectively analyzed. All included patients underwent ultrasound examination of cervical lymph nodes, fine needle aspiration cytology (FNA-C) examination, and ultrasound-guided lymph node aspiration eluent thyroglobulin (FNA-Tg). Typical ultrasound signs for diagnosing cervical lymph node metastasis (US-M) and ultrasound-guided FNA-Tg for diagnosing cervical lymph node metastasis were compared and analyzed.

RESULTS

Results indicate that 71 patients were diagnosed with cervical lymph node metastasis through surgery and subsequently included in the metastatic group; the remaining 68 patients were included in the nonmetastatic group. The FNA-Tg value in the metastatic group was higher than that in the nonmetastatic group; the difference was significant (p < 0.001). The AUC values for diagnosing cervical lymph node metastasis in PTC patients using US-M, FNA-Tg, and US-M+FNA-Tg were 0.854, 0.927, and 0.952. When the cut-off value of FNA-Tg was 229.1 ng/mL, the sensitivity and specificity for diagnosing cervical lymph node metastasis in PTC patients were 84.5% and 89.5%.

CONCLUSIONS

Ultrasound-guided FNA-Tg level is closely related to cervical lymph node metastasis in patients with PTC. The combination of ultrasound examination and FNA-Tg testing significantly enhances the accuracy of predicting lateral cervical lymph node metastasis in patients with PTC.

Predictive Values of Clinical Features and Multimodal Ultrasound for Central Lymph Node Metastases in Papillary Thyroid Carcinoma

Papillary thyroid carcinoma (PTC), the predominant pathological type among thyroid malignancies, is responsible for the sharp increase in thyroid cancer. Although PTC is an indolent tumor with good prognosis, 60-70% of patients still have early cervical lymph node metastasis, typically in the central compartment. Whether there is central lymph node metastasis (CLNM) or not directly affects the formulation of preoperative surgical procedures, given that such metastases have been tied to compromised overall survival and local recurrence. However, detecting CLNM before operation can be challenging due to the limited sensitivity of preoperative approaches. Prophylactic central lymph node dissection (PCLND) in the absence of clinical evidence of CLNM poses additional surgical risks. This study aims to provide a comprehensive review of the risk factors related to CLNM in PTC patients. A key focus is on utilizing multimodal ultrasound (US) for accurate prognosis of preoperative CLNM and to highlight the distinctive role of US-based characteristics for predicting CLNM.

Lateral neck dissection for the treatment of synchronous and metachronous lateral neck metastasis of N1b papillary thyroid cancer

Introduction

Metachronous lateral neck recurrence after thyroidectomy for N1b papillary thyroid cancer is accompanied by high morbidity and increased difficulty of reoperation. From the perspective of recurrence, the objective of this study was to compare patients who underwent metachronous lateral neck dissection (mLND) despite initial thyroidectomy and patients who underwent synchronous lateral neck dissection (sLND) for papillary thyroid cancer and analyze the risk factors for recurrence after mLND.

Method

This retrospective study involved 1,760 patients who underwent lateral neck dissection for papillary thyroid cancer at the Gangnam Severance Hospital, a tertiary medical center in Korea, from June 2005 to December 2016. The primary outcome was structural recurrence, and secondary outcome measures were risk factors of recurrence in the mLND group.

Result

A total of 1,613 patients underwent thyroidectomy and sLND at diagnosis. In 147 patients, thyroidectomy alone was performed at the time of diagnosis, and mLND was performed when recurrence to the lateral neck lymph node was confirmed. During a median follow-up of 102.1 months, 110 (6.3%) patients experienced a recurrence. There was no significant difference in the recurrence between the sLND and mLND groups (6.1% vs 8.2%, P=.32). The period from lateral neck dissection to recurrence was longer in the mLND group than in the sLND group (113.6 ± 39.4 months vs 87.0 ± 33.8 months, respectively, P<.001). Age ≥50 years (adjusted HR=5.209, 95% CI=1.359-19.964; P=.02), tumor size >1.45 cm (adjusted HR=4.022, 95% CI=1.036-15.611; P=.04), and lymph node ratio in the lateral compartment (adjusted HR=4.043, 95% CI=1.079-15.148; P=.04) were independent variables predictive of recurrence after mLND.

Conclusion

mLND is suitable for treating lateral neck recurrence in patients with N1b papillary thyroid cancer who previously underwent thyroidectomy. Lateral neck recurrence after treatment in patients who underwent mLND was predicted by age, tumor size, and lymph node ratio in the lateral compartment.

What Are the Characteristics of Papillary Thyroid Microcarcinoma Prone to High-Volume Lateral Lymph Node Metastasis? - An Analysis of 2981 Consecutive Cases

PURPOSE

To identify candidate factors for predicting high-volume lateral lymph node metastasis (LLNM) in papillary thyroid microcarcinoma (PTMC).

METHODS

We retrospectively studied 2981 patients with PTMC who underwent thyroidectomy from 2013 to 2016. LLNM was identified by histopathology. Patients with different LLNM statuses were compared according to clinical, sonographic and pathological parameters. A multivariate logistic model was established to predict high-volume LLNM (number of metastatic lymph nodes >5).

RESULTS

High-volume LLNM of PTMC was independently associated with age < 40 years (OR = 1.791, P = 0.023), male sex (OR = 2.401, p = 0.001), tumor size > 0.5 cm (OR = 4.839, p < 0.001), extrathyroidal extension (OR = 2.097, p = 0.007) and microcalcification (OR = 2.894, p = 0.002). These five factors were incorporated together to develop a multivariate analysis, which showed good predictive ability (AUC = 0.78, 95% CI 0.72-0.83), with a sensitivity of 80.0% and a specificity of 61.4%. Moreover, more level II or V lateral regions were involved in patients with high-volume LLNM than in those with small-volume LLNM (69.2% vs. 25.0%, p < 0.001; 10.8% vs. 4.7%, p < 0.001).

CONCLUSION

Multilevel LLNM tended to be more common in patients with PTMC who had high-volume LLNM. The high-volume LLNM rates of patients with PTMC with age < 40 years, male sex, tumor size > 0.5 cm, extrathyroidal extension and microcalcification were relatively higher than those without. These findings may be useful for identifying patients at higher high-volume LLNM risk who may require more aggressive treatment or intensive follow-up management.

Advanced Ultrasound Techniques for Differentiation of Benign Versus Malignant Thyroid Nodules: A Review

ABSTRACT

Grayscale ultrasound (US) is decisive in stratifying which thyroid nodules benefit from fine-needle aspiration to evaluate for malignancy. Unfortunately, a significant percentage of nodules remain indeterminate.Herein, we review the clinical considerations and diagnostic accuracy of advanced US, Doppler US, contrast-enhanced US, and US elastography techniques in the evaluation of indeterminate nodules.We conclude that these techniques may be used in combination with grayscale US to improve the assessment of lesion vascularity and tissue property.

Analysis of vascularization in thyroid gland nodes with superb microvascular imaging (SMI) and CD34 expression histology: a pilot study

Background

The Doppler sonography technique known as "superb microvascular imaging" (SMI) is advancing sonographic micro vascularization imaging in various disciplines. In this study, we aimed to determine whether SMI could reliably reproduce the blood flow in thyroid nodes and whether malignancy could be diagnosed, based on vascularization properties. Immunhistochemical staining by CD34 and SMI where used to determine the vascularization of nodes in terms of quantified vascularization parameters gained by computational evaluation.

Methods

We used image analysis programs to investigate whether the quantitative value for vascularization strength in the thyroid node, measured with SMI, was correlated with the actual degree of vascularization, determined microscopically. We included 16 patients that underwent thyroid resections. We prepared thyroid gland tissue slices for immunohistochemistry and labelled endothelial cells with CD34 to visualize blood vessels microscopically. We used image analysis programs, ImageJ, to quantify SMI Doppler sonographic measurements and CellProfiler to quantify CD34 expression in histological sections. We evaluated the numeric values for diagnostic value in node differentiation. Furthermore, we compared these values to check for correlations.

Results

Among the 16 nodes studied, three harboured malignant tumours (18.75%): two papillary and one follicular carcinoma. Among the 13 benign lesions (81.25%), four harboured follicular adenomas. Malignant and benign nodes were not significantly different in sonographic (0.88 ± 0.89 vs. 1.13 ± 0.19; p = 0.2790) or immunohistochemical measurements of vascularization strength (0.05 ± 0.05 vs. 0.08 ± 0.06; p = 0.2260).

Conclusion

We found a positive, significant correlation (r = 0.55588; p = 0.0254) between SMI (quantitative values for vascularization strength) and immunohistochemistry (CD34 staining) evaluations of thyroid nodes.

Risk Factors for Lymph Node Metastasis in Papillary Thyroid Carcinoma: A Systematic Review and Meta-Analysis

Purpose: To explore the risk factors that may predict the lymph node metastasis potential of these lesions and new prevention strategies in papillary thyroid carcinoma patients. Materials and Methods: In total, 9,369 papillary thyroid carcinoma patients with 37.17% lymph node metastasis were analyzed (Revman 5.3 software) in this study. The PubMed and Embase databases were used for searching works systematically that were published through to January 22, 2020. Results: Several factors were related to the increased risk of lymph node metastasis in patients with papillary thyroid carcinoma: age <45 years (pooled OR = 1.52, 95% CI = 1.14-2.01, p <0.00001); gender = male (pooled OR = 1.68, 95% CI = 1.51-1.87, p <0.00001); multifocality (pooled OR = 2.05, 95% CI = 1.45-2.89, p <0.0001); tumor size ≥1.0 cm (pooled OR = 3.53, 95% CI = 2.62-4.76, p <0.00001); tumor location at the upper pole 1/3 (pooled OR =1.46, 95% CI = 1.04-2.04, p = 0.03); capsular invasion + (pooled OR = 3.48, 95% CI = 1.69-7.54, p = 0.002); and extrathyroidal extension + (pooled OR = 2.03, 95% CI= 1.78-2.31, p <0.00001). However, tumor bilaterality (pooled OR = 0.85, 95% CI = 0.54-1.34, p = 0.49) and Hashimoto's thyroditis (pooled OR = 1.08, 95% CI = 0.79-1.49, p = 0.62) showed no correlation with lymph node metastasis in papillary thyroid carcinoma patients. Conclusion: The systematic review and meta-analysis defined several significant risk factors of lymph node metastasis in papillary thyroid cancer patients: age (<45 years), gender (male), multifocality, tumor size (>1 cm), tumor location (1/3 upper), capsular invasion, and extra thyroidal extension. Bilateral tumors and Hashimoto's thyroiditis were unrelated to lymph node metastasis in patients with papillary thyroid cancer.

Clinical and Ultrasonic Risk Factors for Lateral Lymph Node Metastasis in Papillary Thyroid Microcarcinoma: A Systematic Review and Meta-Analysis

Background: Clinical and ultrasonic risk factors for lateral lymph node metastasis (LLNM) in papillary thyroid microcarcinoma (PTMC) are not well-defined. Herein, a systematic review and meta-analysis was conducted to investigate clinicopathologic and ultrasonic risk features for LLNM in PTMC.

Methods: A systematic search of electronic databases (PubMed, Embase, Cochrane Library, and Web of Science) for studies published until April 2019 was performed. Case–control studies and randomized controlled trials that studied clinical and ultrasonic risk factors of LLNM in PTMC were included.

Results: Fourteen studies (all retrospective studies) involving 43,750 patients met final inclusion criteria. From the pooled analyses, younger age<45 (OR, 1.55; 95% CI, 1.16–2.07; P = 0.003), male patients (OR, 1.94; 95% CI, 1.55–2.42; P < 0.00), extrathyroidal extension (OR, 3.63; 95% CI, 2.28–5.77; P <0.00), tumor multifocality (OR, 2.24; 95% CI, 1.53–3.28; P <0.00), tumor > 0.5 cm (OR, 2.24; 95% CI, 1.53–3.28; P < 0.00), central lymph node metastasis (OR, 5.61; 95% CI, 4.64–6.79; P < 0.00), >25% tumor contact with thyroid capsule (OR, 6.66; 95% CI, 1.96–22.65; P = 0.002), tumor calcification (OR, 2.90; 95% CI, 1.71–4.93; P < 0.00), upper tumor (OR, 3.18; 95% CI, 2.23–4.55; P < 0.00) were significantly associated with increased risk of LLNM in PTMC, while Hashimoto's thyroiditis and other ultrasonic features (solid tumor, hypoechoic tumor, smooth margin, and taller than wide tumor) were not significantly associated with LLNM in PTMC.

Conclusions: Our analysis identified several clinicopathologic and ultrasonic factors associated with LLNM in PTMC. This finding highlights the need for a cautious and frequent postoperative surveillance of the lateral neck in high-risk PTMC patients. Moreover, high-risk ultrasonic features also need to be considered during selection of PTMC for active surveillance.

Risk Factors of Metastatic Lymph Nodes in Papillary Thyroid Microcarcinoma

INTRODUCTION

Papillary thyroid microcarcinoma (PTMC) usually has an indolent course, but some have worse prognostic factors, such as the presence of central (6.9%-51.5%) and lateral (3%-49.6%) lymph node metastases. The aim of this study is to analyze the factors associated with PTMC with metastatic lymph nodes and its long-term prognosis.

METHODS

Retrospective study whose study population consists of patients with PTMC (size ≤1cm). Patients with previous thyroid surgery, other synchronous malignancies and ectopic location of the PTMC were excluded. Two groups were compared: PTMC without metastatic lymph nodes (group 1) and PTMC with metastatic lymph nodes (group 2). A multivariate analysis using a logistic regression model and a Kaplan-Meier survival analysis with log-rank test were performed.

RESULTS

Out of the 161 selected patients, 9.3% (n=15) had metastatic lymph nodes. Multifocality (OR 5.284, 95%CI 1.056-26.443; P=.043) and extrathyroidal extension (OR 7.687, 95%CI 1.405-42.050; P=.019) were associated with the presence of metastatic lymph nodes. In PTMC with metastatic lymph nodes, more aggressive treatments were performed: lymphadenectomy (4.8% vs. 100%; P<.001) and radioactive iodine (24.7% vs. 100%; P<.001). During a mean follow-up of 119.8±65 months, one recurrence was detected in group 2 (0% vs. 6.7%; P=.093). No patients died due to the disease.

CONCLUSIONS

Multifocality and extrathyroidal extension of PTMC were associated with the presence of metastatic lymph nodes. Metastatic PTMC, with more aggressive treatments, presents an excellent long-term prognosis.

Establishing a prediction model for lateral neck lymph node metastasis in patients with papillary thyroid carcinoma

This study aimed to establish a model for predicting lateral neck lymph node metastasis in patients with papillary thyroid carcinoma. A total of 106 patients with papillary thyroid carcinoma undergoing initial treatment of neck lymph node dissection (including central and lateral neck lymph nodes) at the thyroid surgery department were enrolled from January 2009 to April 2017. Logistic regression analysis was used to screen the factors influencing lateral neck lymph node metastasis and develop a prediction model. The receiver operating characteristic curve was used to evaluate the predictive power and boundary value of the model for lateral neck lymph node metastasis. Prediction model: Logistic(P) = -5.699 + 0.681 × (TSH) + 0.342 × (Metastatic rate of central lymph nodes) + 1.463 × (Combined with Hashimoto's disease) + 1.525 × (Number of tumors). When logistic (P) was ≥ 0.821, it was predicted that lateral neck lymph node metastasis occurred in patients with papillary thyroid carcinoma. When logistic (P) was <0.821, it was predicted that no metastasis was found in the lateral neck lymph node. The prediction accuracy was 78.3%. The model helped in evaluating lateral neck lymph node metastasis in patients with papillary thyroid carcinoma. Also, it had significance in determining reasonable surgical range, reducing unnecessary lateral neck lymph node dissection, and further improving the quality of life of patients.

Overview of advances in vasculogenic mimicry - a potential target for tumor therapy

Vasculogenic mimicry (VM) describes the process utilized by highly aggressive cancer cells to generate vascular-like structures without the presence of endothelial cells. VM has been vividly described in various tumors and participates in cancer progression dissemination and metastasis. Diverse molecular mechanisms and signaling pathways are involved in VM formation. Furthermore, the patterning characteristics of VM, detected with molecular imaging, are being investigated for use as a tool to aid clinical practice. This review explores the most recent studies investigating the role of VM in tumor induction. Indeed, the recognition of these advances will increasingly affect the development of novel therapeutic target strategies for VM in human cancer.

Lateral lymph node metastasis in papillary thyroid carcinoma: A systematic review and meta-analysis for prevalence, risk factors, and location

BACKGROUND

Lymph node metastasis (LNM) is frequent in papillary thyroid carcinoma (PTC) and is associated with a poor prognosis. Unlike central LNM (CLNM), there are few studies focusing on LLNM. We aimed to investigate the prevalence and the risk factors for LLNM, with its most prevalent sites.

METHODS

We performed a comprehensive literature search using the PubMed and EMBASE databases for relevant studies published prior to November 2016 that examined the risk factors for LLNM.

RESULTS

Twenty-three studies, including 18,741 patients, were included. The prevalence of LLNM was 20.9% in all patients. CLNM (pooled OR = 7.84, 95% CI = 6.13-10.02, p < .0001), extrathyroidal extension (pooled OR = 3.22, 95% CI = 2.21-4.70, p < .0001), tumor multifocality (pooled OR = 2.19, 95% CI = 1.67-2.89, p < .0001), male sex (pooled OR = 1.72, 95% CI = 1.50-1.98, p < .0001), upper pole location (pooled OR = 2.96, 95% CI = 1.93-4.53, p < .0001), tumor size ≥1.0 cm (pooled OR = 2.49, 95% CI = 1.71-3.61, p < .0001), lymphovascular invasion (pooled OR = 3.96, 95% CI = 2.61-6.03, p < .0001) and tumor bilaterality (pooled OR = 1.31, 95% CI = 1.12-1.53, p = .0006) were significantly associated with LLNM. Most frequently affected areas were levels III and IV.

CONCLUSIONS

The prevalence of LLNM was high although the prognostic impact is unknown. The significant risk factors for LLNM were not much different from known risk factors for CLNM.

Clinicopathological features for predicting central and lateral lymph node metastasis in papillary thyroid microcarcinoma: Analysis of 66 cases that underwent central and lateral lymph node dissection

Currently the surgical approach for papillary thyroid microcarcinoma (PTMC), particularly the range of lymph node dissection, remains controversial. The present study aims to evaluate the risk factors for central and lateral lymph node metastasis (CLNM and LLNM) for appropriate clinical decision of neck lymph node dissection in PTMC. A total of 66 cases of PTMC that underwent unilateral or bilateral lobectomy plus prophylactic cervical lymph node dissection were collected for clinicopathological evaluation, including age, gender, tumor size, subtypes, extrathyroidal invasion, multifocality, calcifications, loss of cellular polarity/cohesiveness (LOP/C) in the invasive front, CLNM and LLNM, and retrospectively analysis. Univariate analysis revealed that LOP/C was significantly associated with CLNM (P=0.001) and LLNM (P<0.0001). The male gender was a risk factor of CLNM (P=0.04), while the age <45 years, tumor size >0.5 cm and multifocality were high-risk factors of LLNM (P=0.022, 0.044 and 0.005, respectively). Multivariable analysis revealed that LOP/C was significantly associated with CLNM [P=0.007, odds ratio (OR)=7.765, 95% confidence interval (CI)=1.773–33.996] and LLNM [P=0.029, OR=5.717, 95% CI=1.190–27.470]. Both multivariable analysis and χ² test revealed that CLNM was another important high-risk factor of LLNM (P=0.021, OR=5.444, 95% CI=1.290–22.969, χ²=17.867, P<0.001). The present study revealed that prophylactic central lymph node dissection is essential for PTMC surgery and that prophylactic lateral lymph node dissection is recommend for patients with LOP/C and CLNM, which can be performed by intraoperative frozen section pathological examination. This must be considered discreetly in the case of patients with age <45 years, tumor size >0.5 cm and multifocal lesions.

Predicting lymph node metastasis in patients with papillary thyroid carcinoma by vascular index on power Doppler ultrasound

BACKGROUND

For patients with papillary thyroid carcinoma (PTC), lymph node metastasis is associated with an increased recurrence rate. The purpose of this study was to investigate whether the vascular endothelial growth factor (VEGF), microvessel density (MVD), and vascular index (VI) can predict lymph node metastasis in patients with PTC.

METHODS

From January 2011 to October 2011, 202 patients with PTCs underwent preoperative staging ultrasound evaluation. To evaluate vascularity, we measured the VI, VEGF expression, and MVD.

RESULTS

The VI was significantly correlated with MVD (p = .009). On multivariate analysis, young age showed a significant correlation with lymph node metastasis (p < .001; p < .001; p < .001). However, the other clinicopathologic features, VEGF, MVD, and VI failed to show any significant correlations with lymph node metastasis.

CONCLUSION

Although the VI showed significant correlation with MVD, it was not significantly correlated to lymph node metastasis. © 2016 Wiley Periodicals, Inc. Head Neck 39: 334-340, 2017.

Prognostic Impact of Ultrasonography Features and (18)F-Fluorodeoxyglucose Uptake in Patients With Papillary Thyroid Microcarcinoma

Objectives

To evaluate the prognostic impact of ultrasonography (US) features and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) uptake in patients with papillary thyroid microcarcinoma (PTMC).

Methods

This study included 74 patients with a single PTMC diagnosed pathologically. Patients underwent total thyroidectomy, or near-total thyroidectomy and staging thyroid US and positron emission tomography (PET) were performed prior to surgery. US features of thyroid nodules were reviewed retrospectively and the maximum standard uptake value (SUV) of nodules was semiquantitatively analyzed on ¹⁸F-FDG PET/computed tomography (CT). Patients were followed-up for recurrence, which was defined as PTC on cytology results, elevated serum thyroglobulin (Tg) or anti-Tg antibody levels, or uptake on whole-body scintigraphy. We used univariate and multivariate analyses to evaluate whether poor prognostic outcomes were associated with US features or SUV values derived from PET/CT of nodules. In addition, subjects were divided into 2 groups for subgroup analyses: one with nodules equal to or larger than 5 mm and one with nodules smaller than 5 mm.

Results

Among the 74 patients, there was no recurrence. Thus we evaluated the correlation between SUV value and US features with poor prognostic factors of PTMC which included extrathyroid extension, central and lateral lymph node (LN) metastasis. However no clinicopathologic factors were associated with extrathyroid extension, central LN metastasis, or lateral LN metastasis.

Conclusion

In patients with PTMC, US features and SUV values on FDG-PET were not related to extrathyroid extension or LN metastasis. However, future studies with a larger sample size and longer follow-up should be performed to verify the results of this study.

Value of additional von Kossa staining in thyroid nodules with echogenic spots on ultrasound

PURPOSE

To evaluate the clinical value of additional von Kossa staining on cytology in thyroid nodules with echogenic spots on ultrasound (US).

MATERIALS AND METHODS

342 thyroid nodules were analyzed for cytology and von Kossa staining was performed to detect microcalcifications. We compared diagnostic performances and accuracies of FNA and FNA with von Kossa staining to detect malignancy. We evaluated associations of aggressive pathologic features and von Kossa positivity in the surgically confirmed papillary thyroid carcinoma (PTC) group.

RESULTS

Two hundred and thirty two (67.8%) nodules were malignant and 110 (32.2%) were benign on cytopathology. Compared to cytology alone, additional von Kossa staining slightly improved sensitivity from 89.7% to 90.9% (P=0.081). In 207 cases of surgically confirmed PTC, von Kossa positivity was an independent predictor of central lymph node metastasis in PTCs by multivariate analysis (odds ratio, 2.218; P=0.021).

CONCLUSIONS

Adding von Kossa staining to cytology improved the sensitivity of thyroid nodules with echogenic spots on US. Positive von Kossa stains in PTCs may also be useful in predicting central lymph node metastasis.

Quantitative Evaluation of Vascularity Using 2-D Power Doppler Ultrasonography May Not Identify Malignancy of the Thyroid

The purpose of this study was to evaluate the usefulness of a quantitative vascular index in predicting thyroid malignancy. A total of 1309 thyroid nodules in 1257 patients (mean age: 50.2 y, range: 18-83 y) were included. The vascularity pattern and vascular index (VI) measured by quantification software for each nodule were obtained from 2-D power Doppler ultrasonography (US). Gray-scale US + vascularity pattern was compared with gray-scale US + VI with respect to diagnostic performance. Of the 1309 thyroid nodules, 927 (70.8%) were benign and 382 (29.2%) were malignant. The area under the receiver operating characteristics curve (Az) for gray-scale US (0.82) was significantly higher than that for US combined with vascularity pattern (0.77) or VI (0.70, all p < 0.001). Quantified VIs were higher in benign nodules, but did not improve the performance of 2-D US in diagnosing thyroid malignancy.

A Meta-analysis of Central Lymph Node Metastasis for Predicting Lateral Involvement in Papillary Thyroid Carcinoma

OBJECTIVE

Whether central lymph node metastasis is a reliable indicator of lateral lymph node metastasis in papillary thyroid carcinoma remains obscure. To investigate the value of central lymph node metastasis for predicting lateral compartment involvement, we performed a meta-analysis of published studies.

DATA SOURCES

A systematic literature search of PubMed, EMBASE, and Chinese National Knowledge Infrastructure databases was completed, and the reference lists of the identified articles and prior relevant reviews were examined.

REVIEW METHODS

Two reviewers extracted data and assessed the quality of eligible studies independently. Odds ratios and 95% confidence intervals were pooled through a random effects meta-analysis model.

RESULTS

Twenty-one studies were eligible and further analyzed in this meta-analysis. The risk of lateral lymph node metastasis was significantly higher in the central lymph node-positive group than in the negative group (odds ratio = 7.64, 95% confidence interval: 5.59-10.44), with moderate heterogeneity across studies (P = .007, I(2) = 48.6%). Subgroup analyses and sensitivity analysis suggested that the results were consistent and credible. However, Begg's funnel plot and Egger linear regression test revealed a likelihood of publication bias (P = .000).

CONCLUSION

This meta-analysis suggests that central lymph node metastasis is valuable for predicting lateral compartment involvement in patients with papillary thyroid carcinoma. For those patients with central lymph node metastasis, additional attention should be paid to the lateral neck, as the risk of lateral lymph node metastasis was significantly higher in the central lymph node-positive group than in the negative group. Further studies regarding appropriate management for patients with high risk of lateral involvement are needed.

Thyroid Nodules: Nondiagnostic Cytologic Results according to Thyroid Imaging Reporting and Data System before and after Application of the Bethesda System

PURPOSE

To compare the malignancy rates and the effectiveness of the Thyroid Imaging Reporting and Data System (TIRADS) for risk stratification of nodules with nondiagnostic results classified before and after application of the Bethesda System for Reporting Thyroid Cytopathology.

MATERIALS AND METHODS

This retrospective study was approved by an institutional review board, with waiver of informed consent. A total of 763 patients with 790 thyroid nodules and nondiagnostic cytologic results were included (mean age ± standard deviation, 52.3 years ± 11.5), 485 nodules from the pre-Bethesda period (from March 2007 to December 2008) and 305 nodules from the post-Bethesda period (from May 2011 to May 2012). A TIRADS category was assigned to each thyroid nodule on the basis of the number of features that appeared suspicious for cancer at ultrasonography (US). Malignancy rates and TIRADS categories during the two periods were compared. Correlation between TIRADS category and malignancy risk between the two periods was evaluated and compared.

RESULTS

The malignancy rates of nodules with nondiagnostic cytologic results were not significantly different between the two periods (P = .148). Malignancy risk of TIRADS category 3, 4a, 4b, 4c, and 5 was 1.8%, 5.7%, 4.1%, 29.8%, and 16.7%, for the pre-Bethesda period, and 1.6%, 3.0%, 7.1%, 16.3%, and 25.0% for the post-Bethesda period, respectively. Near-perfect correlation was seen between the TIRADS category and malignancy risk in the post-Bethesda period (r = 0.961, P = .009), while no significant correlation was found in the pre-Bethesda period (r = 0.731, P = .161).

CONCLUSION

Malignancy risk stratification with TIRADS was more effective for nodules with nondiagnostic cytologic results classified according to the Bethesda System. When these Bethesda-classified nodules with nondiagnostic results are evaluated as TIRADS category 3 or 4a, they may be treated conservatively with follow-up US, but when other cytologic classifications are applied, follow-up US and fine- needle aspiration must be considered for nodules showing one or more features suspicious for cancer at US.

Intraoperative ultrasonography is useful in surgical management of neck metastases in differentiated thyroid cancers

Differentiated thyroid carcinomas are the most common malignancies of endocrine organs. Metastases to cervical lymph nodes occur in 20-50% of cases. Recurrence and survival rates are closely related to the type of surgery performed. High-resolution ultrasonography (USG) is a sensitive imaging method used to detect occult lymph node metastases in patients with thyroid cancer. We evaluated how intraoperative USG affected surgical success. This was a retrospective study comparing two groups of patients with thyroid carcinoma who underwent cervical lymph node dissection. A total of 101 patients (33 males and 68 females) were included. Group 1 included 53 patients who underwent surgery with intraoperative USG guidance. Group 2 included 48 patients who underwent surgery without the use of USG. All patients were followed up (mean 23 months; range 5-44 months) with thyroglobulin measurements and USG evaluations. Group 1 (intraoperative USG) had a residual/recurrent tumor rate of 1.9% (1/53 patients). Group 2 had a residual/recurrent tumor rate of 12.5% (6/48 patients). A statistically significant difference appeared between the residual/recurrent tumor rates in Groups 1 and 2 (p<0.05). In addition to its classical use in diagnosis and follow-up, intraoperative use of high-resolution USG can improve surgical success and may decrease the number of residual/recurrent tumors encountered during follow-up.