The diagnostic and prognostic role of miR-146b-5p in differentiated thyroid carcinomas

Introduction

Samples classified as indeterminate correspond to 10-20% of cytologies obtained by fine needle biopsy of thyroid nodules, preventing an adequate distinction between benign and malignant lesions and leading to diagnostic thyroidectomies that often prove unnecessary, as most cases are benign. Furthermore, although the vast majority of patients with differentiated thyroid cancer (DTC) have such a good prognosis that active surveillance is permitted as an initial therapeutic option, relapses are not rare, and a non-negligible number of patients experience poor outcomes. MicroRNAs (miR) emerge as potential biomarkers capable of helping to define more precise management of patients in all these situations.

Methods

Aiming to investigate the clinical utility of miR-146b-5p in the diagnostic of thyroid nodules and evaluating its prognostic potential in a realworld setting, we studied 89 thyroid nodule samples, correlating miR-146b-5p expression with clinical tools such as the 8th edition from the American Joint Committee on Cancer (AJCC/UICC) and the American Thyroid Association Guideline Stratification Systems for the rate of recurrence (RR).

Results

miR-146b-5p expression levels distinguished benign from malignant thyroid FNA samples (p< 0.0001). For indeterminate nodules, overexpression of miR-146b-5p with a cut-off of 0.497 was able to diagnose malignancy with a 90% accuracy; specificity=87.5%; sensitivity=100%. An increased expression of miR-146b-5p was associated with greater RR (p=0.015). A cut-off of 2.21 identified cases with more vascular involvement (p=0.013) and a cut-off of 2.420 was associated with a more advanced TNM stage (p-value=0.047).

Discussion

We demonstrated that miR-146b5p expression in FNA samples is able to differentiate benign from malignant indeterminate nodules and is associated with an increased risk of recurrence and mortality, suggesting that this single miRNA may be a useful diagnostic and prognostic marker in the personalized management of DTC patients.

Bilateral papillary thyroid cancer: pitfalls of ACR TI-RADS and evaluation of modified parameters

PURPOSE

To explore modified parameters of the American College of Radiology Thyroid Imaging Reporting and Data System (TI-RADS) for evaluating contralateral nodules based on preoperative ultrasound features of papillary thyroid carcinoma (PTC) in the suspected lobe, thus guiding the management of bilateral PTC.

METHODS

We retrospectively analyzed 389 consecutive patients with PTC (272 in training set, 117 in validation set) who underwent total thyroidectomy from March 2020 to March 2022. According to their postoperative pathological data, the patients were divided into unilateral and bilateral PTC groups. The clinicopathological features and sonographic characteristics of suspected nodules were compared between the groups, and further ultrasonic characteristics of TI-RADS grade (TR grade)-underestimated nodules were analyzed.

RESULTS

Patients with a body mass index of ≥25 kg/m2 (P < 0.001), multifocality in the suspected lobe (P < 0.001), and TR > 3 isthmus nodules (P = 0.003) tended to have bilateral PTC. After modifying the TI-RADS classification for contralateral nodules using these three parameters, the area under the curve for diagnosing contralateral lesions increased from 0.79 (95% confidence interval, 0.74-0.84) to 0.83 (0.78-0.87) in the training set. The missed diagnosis rate of contralateral PTC decreased in both the training set [21.1% (28/133) to 4.5% (6/133)] and validation set [11.4% (8/70) to 2.9% (2/70)]. Preoperative ultrasound tended to underestimate the contralateral nodules with the presence of cystic components [100% (6/6)] and halo sign [73.3% (11/15)].

CONCLUSION

The modified TI-RADS classification based on the suspected lobe may facilitate effective preoperative malignant risk stratification of contralateral nodules in bilateral PTC.

Incidence and Clinicopathological Features of Differentiated High-Grade Thyroid Carcinomas: An Institutional Experience

Differentiated high-grade thyroid carcinoma (DHGTC) is a new entity in the 2022 WHO classification. We aimed to investigate the incidence and clinicopathological features of differentiated HG thyroid carcinoma (DHGTC) and compare the clinicopathological parameters of DHGTC, DTC without HG features, and poorly differentiated thyroid carcinoma (PDTC). A total of 1069 DTCs including papillary thyroid carcinomas (PTCs) and follicular thyroid carcinomas (FTCs) were included in this study. Consecutive 22 PDTCs were also included for comparative purposes. There were a total of 14 (1.3%) cases of DHGTCs, with 13 HGPTCs (1.2% of PTCs) and one HGFTC (6.7% of FTCs). Compared to DTCs without HG features, DHGTCs were associated with larger tumor size, presence of blood vessel invasion, gross extrathyroidal extension, distant metastasis at the time of diagnosis, higher American Joint Committee on Cancer stage, high American Thyroid Association risk, and TERT promoter mutations. DHGTC and PDTC showed a significantly shorter recurrence-free survival (RFS) than DTC without HG features. Multivariate Cox regression analysis revealed that blood vessel invasion, lateral node metastasis, TERT promoter mutations, and HG features were independent prognostic factors (all p < 0.05). When tumor necrosis and increased mitotic count were evaluated separately, tumor necrosis, but not increased mitotic counts, was found to be an independent prognostic factor (p = 0.006). This study confirmed that DHGTC is significantly associated with aggressive clinicopathological features and poor clinical outcomes, similar to PDTC. Although the incidence is low, careful microscopic examination of HG features in DTC is required.

Should multifocality be an indication for prophylactic central neck dissection in papillary thyroid cancer?

Although multifocality is common in patients with papillary thyroid cancer, its effects on lymphatic metastasis and the necessity of central dissection in the presence of multifocality are still controversial. In our clinic, 258 patients who underwent thyroidectomy between 2015 and 2020 and were found to have papillary thyroid cancer in postoperative pathology reports were analyzed. The tumor characteristics contributing to central lymph node metastasis positivity were evaluated. Lymph node metastases were not significantly increased in the presence of multifocality. In cases with bilateral multifocal tumors, compared to cases with unilateral multifocal tumors, capsular invasion (p = 0.02), vascular invasion (p = 0.01) and cervical lymphatic metastasis (p = 0.004) were observed to increase. Bilateral multifocal tumors have more aggressive clinicopathological features than unilateral tumors. We found that the risk of central lymph node metastasis increased significantly in bilateral multifocal tumors in our study. Prophylactic central lymph node dissection may be considered in patients with no preoperative or intraoperative lymph node metastasis but thought to have a multifocal tumor.

Construction of prediction models for determining the risk of lateral lymph node metastasis in patients with thyroid papillary carcinoma based on gender stratification

BACKGROUND

Lateral lymph node metastasis (LLNM) is associated with poor prognosis in patients with papillary thyroid cancer (PTC). The purpose of this study was to determine the risk factors for LLNM and establish prediction models that could individually assessed the risk of LLNM.

METHODS

A total of 619 PTC patients were retrospectively analyzed in our study. Univariate and multivariate analysis were performed for male and female patients, respectively, to assess relationships between clinicopathological features and LLNM. By integrating independent predictors selected by binary logistic regression modeling, preoperative and postoperative nomograms were developed to estimate the risk of LLNM.

RESULTS

LLNM was detected in 80 of 216 male patients. Of 403 female patients, 114 had LLNM. The preoperative nomogram of male patients included three clinical variables: the number of foci, tuner size, and echogenic foci. In addition to the above three variables, the postoperative nomogram of male patients included extrathyroidal extension (ETE) detected in surgery, central lymph node metastasis (CLNM) and high-volume CLNM. The preoperative nomogram of female patients included the following variables: age, chronic lymphocytic thyroiditis (CLT), BRAF V600E, the number of foci, tumor size and echogenic foci. Variables such as CLT, BRAF V600E, the number of foci, tumor size, ETE detected in surgery, CLNM, high-volume CLNM and central lymph node ratio were included in the postoperative nomogram. Above Nomograms show good discrimination.

CONCLUSIONS

Considering the difference in the incidence rate of LLNM between men and women, a separate prediction system should be established for patients of different genders. These nomograms are helpful in promoting the risk stratification of PTC treatment decision-making and postoperative management.

Bilateral multifocality is an independent predictor of patients' outcome in Middle Eastern papillary thyroid carcinoma

Background

Tumor multifocality is frequently seen in Papillary thyroid carcinoma (PTC). However, few studies have analysed the impact of bilateral multifocality in PTC. The incidence of bilateral multifocality, its clinico-pathological associations and prognostic impact in PTC from Middle Eastern ethnicity remains unestablished.

Methods

We retrospectively evaluated 1283 patients who underwent total thyroidectomy for PTC. Bilateral and unilateral multifocality were decided based on the final pathology result. Primary outcome was recurrence free survival (RFS). Risk factors for bilateral multifocality were analyzed by multivariate logistic regression analysis.

Results

Multifocal PTC was found in 54.3% (697/1283) of patients. Among the 697 multifocal PTCs, 210 patients (30.1%) had unilateral multifocal PTC and 487 patients (69.9%) had bilateral multifocality. Bilateral multifocality was significantly associated with older age at diagnosis (p = 0.0263), male gender (p = 0.0201), gross extrathyroidal extension (p = 0.0332), larger primary tumor size (>4cm; p = 0.0002), lateral lymph node metastasis (p = 0.0008), distant metastasis at diagnosis (p = 0.0195) and recurrence (p = 0.0001). Bilateral multifocality was also found to be an independent predictor of RFS (Hazard ratio = 1.60; 95% Confidence Interval = 1.05 - 2.55; p = 0.0300). Multivariate logistic regression analysis demonstrated tumor diameter >4cm to be the only independent risk factors for bilaterality in multifocal PTC (Odds ratio = 1.86; 95% Confidence Interval = 1.13 - 3.07; p = 0.0155).

Conclusions

Incidence of bilateral multifocality is high in Middle Eastern PTC. Tumor diameter >4cm can be considered as a predictive factor for bilateral multifocal PTC. Bilateral multifocality appears to be an important prognostic factor for PTC and an independent predictor of RFS. Therefore, patients with bilateral multifocal PTC may benefit from more frequent follow-up to identify recurrences earlier.

An integrated nomogram combining deep learning, clinical characteristics and ultrasound features for predicting central lymph node metastasis in papillary thyroid cancer: A multicenter study

OBJECTIVE

Central lymph node metastasis (CLNM) is a predictor of poor prognosis for papillary thyroid carcinoma (PTC) patients. The options for surgeon operation or follow-up depend on the state of CLNM while accurate prediction is a challenge for radiologists. The present study aimed to develop and validate an effective preoperative nomogram combining deep learning, clinical characteristics and ultrasound features for predicting CLNM.

MATERIALS AND METHODS

In this study, 3359 PTC patients who had undergone total thyroidectomy or thyroid lobectomy from two medical centers were enrolled. The patients were divided into three datasets for training, internal validation and external validation. We constructed an integrated nomogram combining deep learning, clinical characteristics and ultrasound features using multivariable logistic regression to predict CLNM in PTC patients.

RESULTS

Multivariate analysis indicated that the AI model-predicted value, multiple, position, microcalcification, abutment/perimeter ratio and US-reported LN status were independent risk factors predicting CLNM. The area under the curve (AUC) for the nomogram to predict CLNM was 0.812 (95% CI, 0.794-0.830) in the training cohort, 0.809 (95% CI, 0.780-0.837) in the internal validation cohort and 0.829(95%CI, 0.785-0.872) in the external validation cohort. Based on the analysis of the decision curve, our integrated nomogram was superior to other models in terms of clinical predictive ability.

CONCLUSION

Our proposed thyroid cancer lymph node metastasis nomogram shows favorable predictive value to assist surgeons in making appropriate surgical decisions in PTC treatment.

Intraoperative MET-receptor targeted fluorescent imaging and spectroscopy for lymph node detection in papillary thyroid cancer: novel diagnostic tools for more selective central lymph node compartment dissection

Purpose

Patients undergoing prophylactic central compartment dissection (PCLND) for papillary thyroid cancer (PTC) are often overtreated. This study aimed to determine if molecular fluorescence-guided imaging (MFGI) and spectroscopy can be useful for detecting PTC nodal metastases (NM) and to identify negative central compartments intraoperatively.

Methods

We used a data-driven prioritization strategy based on transcriptomic profiles of 97 primary PTCs and 80 normal thyroid tissues (NTT) to identify tumor-specific antigens for a clinically available near-infrared fluorescent tracer. Protein expression of the top prioritized antigen was immunohistochemically validated with a tissue microarray containing primary PTC (n = 741) and NTT (n = 108). Staining intensity was correlated with 10-year locoregional recurrence-free survival (LRFS). A phase 1 study (NCT03470259) with EMI-137, targeting MET, was conducted to evaluate safety, optimal dosage for detecting PTC NM with MFGI, feasibility of NM detection with quantitative fiber-optic spectroscopy, and selective binding of EMI-137 for MET.

Results

MET was selected as the most promising antigen. A worse LRFS was observed in patients with positive versus negative MET staining (81.9% versus 93.2%; p = 0.02). In 19 patients, no adverse events related to EMI-137 occurred. 0.13 mg/kg EMI-137 was selected as optimal dosage for differentiating NM from normal lymph nodes using MFGI (p < 0.0001) and spectroscopy (p < 0.0001). MFGI identified 5/19 levels (26.3%) without NM. EMI-137 binds selectively to MET.

Conclusion

MET is overexpressed in PTC and associated with increased locoregional recurrence rates. Perioperative administration of EMI-137 is safe and facilitates NM detection using MFGI and spectroscopy, potentially reducing the number of negative PCLNDs with more than 25%.

Clinical trial registration.

NCT03470259.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-022-05763-3.

Bibliometric insights in advances of papillary thyroid microcarcinoma: Research situation, hot points, and global trends

BACKGROUND

Thyroid cancer has been on the rise over the last decade. Papillary thyroid microcarcinoma (PTMC) accounts for more than half of all thyroid cancers. Micropapillary carcinoma of the thyroid is a common but non-fatal form of thyroid cancer. To better comprehend, nearly two decades of scientific outputs were analyzed and summarized using bibliometric methods in this study.

METHODS

Approximately 1098 publications from 2000 and 2021 were included in WoS database through systematic retrieval. The general information was characterized, and developmental skeleton and research frontiers were explored. CiteSpace, VOSviewer, and R, Tableau were used to evaluate and visualize the results.

RESULTS

A total of 1098 publications from across 75 countries were identified. The annual number of publications showed an increasing trend in the past 21 years. China, Korea, the United States of America (USA), Italy, and Japan made remarkable contributions to the research of PTMC. Thyroid was the most productive journal. Miyauchi Akira published maximum articles. The utmost productive institution was the University of Ulsan. Risk stratification, active surveillance, and thermal ablation garnered the attention of researchers leading to novel approaches in the clinical diagnosis and treatment of micropapillary thyroid carcinoma.

CONCLUSIONS

This bibliometric study provides a comprehensive analysis of global productivity, collaboration, and research hotspots within PTMC field, which will aid in directing research toward PTMC in the coming years.

Nomogram model based on preoperative serum thyroglobulin and clinical characteristics of papillary thyroid carcinoma to predict cervical lymph node metastasis

OBJECTIVE

Preoperative evaluation of cervical lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC) has been one of the serious clinical challenges. The present study aims at understanding the relationship between preoperative serum thyroglobulin (PS-Tg) and LNM and intends to establish nomogram models to predict cervical LNM.

METHODS

The data of 1,324 PTC patients were retrospectively collected and randomly divided into training cohort (n = 993) and validation cohort (n = 331). Univariate and multivariate logistic regression analyses were performed to determine the risk factors of central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM). The nomogram models were constructed and further evaluated by 1,000 resampling bootstrap analyses. The receiver operating characteristic curve (ROC curve), calibration curve, and decision curve analysis (DCA) of the nomogram models were carried out for the training, validation, and external validation cohorts.

RESULTS

Analyses revealed that age, male, maximum tumor size >1 cm, PS-Tg ≥31.650 ng/ml, extrathyroidal extension (ETE), and multifocality were the significant risk factors for CLNM in PTC patients. Similarly, such factors as maximum tumor size >1 cm, PS-Tg ≥30.175 ng/ml, CLNM positive, ETE, and multifocality were significantly related to LLNM. Two nomogram models predicting the risk of CLNM and LLNM were established with a favorable C-index of 0.801 and 0.911, respectively. Both nomogram models demonstrated good calibration and clinical benefits in the training and validation cohorts.

CONCLUSION

PS-Tg level is an independent risk factor for both CLNM and LLNM. The nomogram based on PS-Tg and other clinical characteristics are effective for predicting cervical LNM in PTC patients.

Male Gender Is Associated with Lymph Node Metastasis but Not with Recurrence in Papillary Thyroid Carcinoma

BACKGROUND

The incidence of papillary thyroid carcinoma (PTC) is higher in females than in males, but it remains unclear whether gender is associated with the aggressiveness of this disease. We aimed to clarify the influence of gender on the risk of developing lymph node metastasis (LNM) and on the prognosis of PTC patients. Study Design. Retrospective cohort study. Setting. Academic tertiary care center.

METHODS

Clinical data of PTC patients who were admitted to the Department of Endocrine and Breast Surgery, the First Affiliated Hospital of Chongqing Medical University, between January 2013 and December 2018 were retrospectively reviewed. The differences in clinical features and outcomes between female and male patients were compared. Univariate and multivariate logistic regression analyses were conducted to assess the impact of gender on LNM. Kaplan-Meier curves were used to estimate recurrence-free survival (RFS).

RESULTS

A total of consecutive 2536 patients were enrolled in this study. Males accounted for 25.2% (639 cases) of all patients. Central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM) rates were 52.5% (1346/2536) and 22.0% (558/2536), respectively. Male presented with higher LNM rates than female patients (65.7% vs. 51.2%; P < 0.001). Male gender was independently associated with LNM (OR = 1.93, 95% CI: 1.59-2.35; P < 0.001). After full adjustment, male gender still remained significantly associated with CLNM in all subgroups; however, subgroup analyses indicated no significant relationship between gender and LLNM. In addition, after a median follow-up period of 30 months, no significant difference was found in RFS between female and male patients (P=0.15).

CONCLUSIONS

This observational cohort study revealed that male gender was significantly associated with CLNM; whereas, LLNM was not different between female and male PTC patients in southwestern China. Moreover, currently, there is insufficient evidence to justify that male gender is an independent prognostic factor for recurrence.

Impact of Multifocality on the Recurrence of Papillary Thyroid Carcinoma

The incidence of thyroid cancer has dramatically increased over the last few decades, and up to 60% of patients have multifocal tumors. However, the prognostic impact of multifocality in patients with papillary thyroid carcinoma (PTC) remains unestablished and controversial. We evaluate whether multifocality can predict the recurrence of PTC. A total of 1249 patients who underwent total thyroidectomy for PTC at the Ewha Medical Center between March 2012 and December 2019 were reviewed. In this study, multifocality was found in 487 patients (39.0%) and the mean follow-up period was 5.5 ± 2.7 years. Multifocality was associated with high-risk features for recurrence, including extrathyroidal extension, lymph node metastasis, and margin involvement. After adjustment of those clinicopathological features, 10-year disease-free survival was 93.3% in patients with multifocal tumors, whereas those with unifocal disease showed 97.6% (p = 0.011). Multivariate Cox regression analysis indicated that male sex (HR 2.185, 95% CI 1.047–4.559), tumor size (HR 1.806, 95% CI 1.337–2.441), N1b LN metastasis (HR 3.603, 95% CI 1.207–10.757), and multifocality (HR 1.986, 95% CI 1.015–3.888) were independent predictors of recurrence. In conclusion, multifocality increased the risk of recurrence in patients with PTC. Patients with multifocal PTCs may need judicious treatment and follow-up approaches.

Association of Multifocality With Prognosis of Papillary Thyroid Carcinoma: A Systematic Review and Meta-analysis

Importance

Multifocality is common in papillary thyroid carcinoma (PTC), but it is unclear whether multifocal tumors are associated with tumor recurrence or cancer-specific survival.

Objective

To compare tumor recurrence rates in patients with multifocal vs unifocal PTCs.

Data Sources

We searched PubMed, SCOPUS, Web of Science Core Collection, and Cochrane Database of Systematic Reviews for pertinent studies published in English from inception to June 30, 2020.

Study Selection

The search strategy yielded 26 studies that compared tumor recurrence in patients with multifocal vs unifocal PTC.

Data Extraction and Synthesis

Data was extracted in accordance with the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline. Characteristics of study populations and hazard ratio (HR) of multifocality were independently extracted by 2 investigators.

Main Outcomes and Measures

The primary outcome was tumor recurrence and the secondary outcome was cancer-specific survival. Subgroup analysis of the primary outcome was based on primary tumor size, number of tumor foci, and patient age.

Results

Among 26 studies with a total of 33 976 patients, recurrence rates were significantly higher in patients with multifocal PTC than in those with unifocal PTC (pooled HR, 1.81; 95% CI, 1.52-2.14). Cancer-specific survival was comparable between the groups (HR, 1.19; 95% CI, 0.85-1.68). In subgroup analyses, the HRs of multifocality for recurrence were associated with primary tumor size (HRs for PTC ≤1 cm and >1 cm were 1.81 and 1.90, respectively), number of tumor foci (HRs for 2 foci and ≥3 foci were 1.45 and 1.95, respectively), and patient age (HRs for pediatric and adult patients were 3.19 and 1.89, respectively).

Conclusions and Relevance

This systematic review with meta-analysis found that multifocality was significantly associated with an increased risk of recurrence in patients with PTC, while cancer-specific survival showed no difference. Differences in tumor size, number of tumor foci, and patient age should be considered when interpreting the multifocality and the risk of recurrence.

A prediction model incorporating the BRAFV600E protein status for determining the risk of cervical lateral lymph node metastasis in papillary thyroid cancer patients with central lymph node metastasis

BACKGROUND AND OBJECTIVES

Cervical lateral lymph node metastasis (LLNM) is a predictor of poor prognosis for papillary thyroid carcinoma (PTC) patients. However, the risk factors for LLNM remain unclear. The purpose of the study was to examine the risk factors for LLNM and construct a prediction model.

METHODS

With Ethics Committee approval, a total of 1198 PTC patients were retrospectively included in our study. Univariate and multivariate analyses were performed to explore the relationship between clinicopathological characteristics and LLNM. A nomogram for predicting LLNM in PTC patients with central lymph node metastasis (CLNM) was constructed and validated.

RESULTS

The negative BRAF^V600E protein expression was significantly correlated with positive LLNM status in PTC patients. In PTC patients with CLNM, the number of metastatic central lymph nodes (LNN) ≥ 3 and the ratio of metastatic central lymph nodes (LNR) ≥ 0.565 were found to be significantly associated with positive LLNM status. The nomogram for predicting LLNM risk in PTC patients with CLNM incorporated four risk factors: tumor size, the BRAF^V600E protein expression, LNN and LNR. The prediction model showed excellent discrimination, with a C-index of 0.714.

CONCLUSIONS

The negative BRAF^V600E protein expression was more likely to lead to LLNM. LNN ≥3 and LNR ≥0.565 were associated with LLNM risk in PTC patients with CLNM. Our nomogram might assist clinicians in developing individual suitable follow-up strategies for PTC patients with CLNM.

Using ultrasonographic features to predict the outcomes of patients with small papillary thyroid carcinomas: a retrospective study implementing the 2015 ATA patterns and ACR TI-RADS categories

BACKGROUND

The aim of this study was to evaluate whether risk stratification systems using ultrasonographic (US) features show associations with the outcomes of patients with small papillary thyroid carcinomas (PTCs).

METHODS

This retrospective study received institutional review board approval. From March 2007 to February 2010, 775 patients who underwent surgery for small PTCs (10-20 mm) were included. Based on preoperative US features, PTCs were categorized according to the 2015 American Thyroid Association (ATA) guideline and the American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS). The associations of clinicopathological and US features with postoperative patient outcomes were evaluated.

RESULTS

In total, 61 patients had high-volume central lymph node metastasis (CLNM, 7.9%) and 100 patients had lateral lymph node metastasis (LLNM, 12.9%). In univariable analyses, a high number of suspicious US features and higher ACR TI-RADS point totals were significantly associated with both high-volume CLNM (P=0.001, each) and LLNM (P<0.001, each). In multivariable analyses of preoperative features, a higher number of suspicious US features and higher ACR TI-RADS point totals were independently associated with high-volume CLNM (odds ratio [OR], 1.516 and 1.201; P=0.002 and P=0.001, respectively) and LLNM (OR, 1.763 and 1.293; all P<0.001). Individual US features, ATA categories, and ACR TI-RADS point totals were not significantly associated with recurrence or distant metastasis.

CONCLUSION

The number of suspicious US features and the ACR TI-RADS point total are potential risk factors for cervical lymph node metastasis in patients with small PTCs.

Papillary Thyroid Carcinoma Tissue miR-146b, -21, -221, -222, -181b Expression in Relation with Clinicopathological Features

We analyzed miR-146b, miR-21, miR-221, miR-21, and miR-181b in formalin fixed paraffin-embedded papillary thyroid carcinoma (PTC) tissue samples of 312 individuals and evaluated their expression relationship with clinicopathological parameters. A higher expression of miR-21 was related to unifocal lesions (p < 0.011) and autoimmune thyroiditis (0.007). miR-221, miR-222 expression was higher in the PTC tissue samples with extrathyroidal extension (p = 0.049, 0.003, respectively). In a group of PTC patients with pT1a and pT1b sized tumors, the expression of miR-146b, miR-21, miR-221, and miR-222 in PTC tissue samples was lower than in patients with pT2, pT3, and pT4 (p = 0.032; 0.0044; 0.003; 0.001; 0.001, respectively). Patients with lymph node metastases had higher expression of miR-21, -221, -222, and -181b (p < 0.05). A high expression of miR-146b, miR-21, miR-221 panel was associated with decreased overall survival (OS) (Log rank p = 0.019). Univariate analysis revealed that presence of metastatic lymph nodes and high expression of miR-146b, miR-21, and miR-221 panels were associated with increased hazard of shorter OS. After multivariate analysis, only sex (male) and age (≥55 years) emerged as independent prognostic factors associated with shorter OS (HR 0.28 (95% CI 0.09–0.86) and HR 0.05 (95% CI 0.01–0.22), respectively). In conclusion, 5 analyzed miRs expression have significant relations to clinicopathologic parameters so further investigations of these molecules are expedient while searching for prognostic PTC biomarkers.

Role of Sonographic Characteristics of Thyroid Bed Lesions Identified Following Thyroidectomy in the Diagnosis or Exclusion of Recurrent Cancer

Background US of the thyroid bed in patients with thyroid cancer often depicts small lesions, but it is unclear whether US characteristics of lesions can help predict cancer recurrence. Purpose To determine whether size or US features of lesions in the thyroid bed after thyroidectomy in conjunction with clinical features can help predict thyroid cancer recurrence. Materials and Methods With use of a US reporting database, all patients imaged between July 2006 and June 2016 with an indication of post-thyroidectomy follow-up were retrospectively identified. Recorded data included patient demographic characteristics; date of thyroidectomy; thyroid cancer type; presence, size, and US characteristics of thyroid bed lesions; and results of fine-needle aspiration (FNA). Images were reviewed for lesions that underwent FNA. The Fisher exact test was used for analysis. Results A total of 1885 patients (mean age ± standard deviation, 48 years ± 15; 1493 female patients) underwent 5732 US examinations. Most patients (1541 of 1885 [82%]) had papillary cancer. Overall, 3163 thyroid bed lesions were reported in 5732 US examinations (40.4%). More than half of these lesions (1860 of 3163 [58.8%]) had a maximum measurement of 6 mm or greater. FNA was performed in 144 of the 3163 lesions (4.6%), of which 61 (42.4%) were malignant, 33 (22.9%) were benign, and 50 (34.7%) were nondiagnostic. Five nondiagnostic lesions eventually proved malignant. Only the presence of punctate echogenicities in the lesion (28 of 61 malignant lesions [45.9%]; three of 33 benign lesions [9%]; 12 of 50 nondiagnostic lesions [24%]; P < .001) or the history of positive lymph nodes at thyroidectomy (44 of 61 malignant lesions [72.1%]; 10 of 33 benign lesions [30%]; 19 of 50 nondiagnostic lesions [38%]; P < .001) were associated with malignancy. Of 3019 thyroid bed lesions that did not undergo FNA, three were malignant and 2248 showed no growth at follow-up US ranging from 6 months to 10 years and are presumed benign. Of the 1303 lesions smaller than 6 mm, only two (0.2%) were malignant. Conclusion Small lesions are commonly found in the thyroid bed after thyroidectomy, and most are likely to be benign. Lesions smaller than 6 mm with no punctate echogenicities had a minimal risk for malignancy. © RSNA, 2021 See also the editorial by Grant and Malhi in this issue.

Microscopic positive surgical margins in thyroid carcinoma: a proposal for thyroid oncology teams

PURPOSE

In the case of well-differentiated thyroid cancer, the importance of microscopic margin status remains controversial. We discuss the relevance of the effect of microscopic positive surgical margins in the early stages of differentiated thyroid cancer.

METHODS

A comprehensive literature search and review of available evidence in English literature was undertaken.

RESULTS

A previous meta-analysis did not find an association between microscopic positive surgical margins and local recurrence. Heterogeneity of definitions and differences between microscopic surgical margins and extrathyroid extension are discussed. Impact on clinical decision-making is explored.

CONCLUSION

The finding of microscopic positive surgical margins in a patient with a thyroid tumor without intraoperative evidence of macroscopic invasion to adjacent structures, with complete resection made by the surgeon and without pathological report of extrathyroid extension, does not have a worse prognostic effect. We present a classification of surgical margins that may help thyroid oncology teams to tailor further management in patients with thyroid cancer.

Blood-Rich Enhancement in Ultrasonography Predicts Worse Prognosis in Patients With Papillary Thyroid Cancer

Contrast-enhanced ultrasound (CEUS) can be used to evaluate microcirculation in cancers, which in turn is associated with the biologic features and ultimately patient prognosis. We conducted a retrospective analysis to examine potential association between CEUS parameters and prognosis in patients with papillary thyroid cancer (PTC). The analysis included 306 patients who underwent CEUS prior to thyroidectomy at our center during a period from 2012 to 2019. Subjects with excellent response (ER) were compared to the non-ER group (including indeterminate response, biochemical incomplete response and structural incomplete response). During the median follow-up of 34 months, ER was observed in 195 (63.7%) subjects. The remaining 111 (36.3%) patients developed non-ER events, with distant metastasis in five (1.6%) cases. In a multivariate COX regression, non-ER event was associated with the male sex (OR = 1.83, 95%CI: 1.21-2.76) and blood-rich enhancement in CEUS (OR = 1.69, 95%CI: 1.04-2.75). Based on this finding, we developed a predictive model: high risk for developing non-ER events was defined as having both risk factors; low risk was defined as having none or only one risk. In receiver operating characteristic (ROC) analysis, the area under the curve was 0.59 (95%CI: 0.52-0.66). The sensitivity and specificity were 17.1 and 95.4%, respectively. The positive and negative predictive values were 67.9 and 66.9%, respectively. In conclusion, blood-rich enhancement in CEUS is associated with non-ER events after thyroidectomy in patients with PTC.

Large-Volume Lateral Lymph Node Metastasis Predicts Worse Prognosis in Papillary Thyroid Carcinoma Patients With N1b

We aimed to evaluate the relevance of large-volume lateral lymph node metastases (LLNMs) at risk of recurrence/persistence in papillary thyroid carcinoma (PTC) with LLNMs (N1b). This retrospective study included 448 PTC patients, who had positive LLNMs confirmed by histology and suspected of LLNMs by preoperative ultrasound. According to the number of pathological LLNMs, patients were divided into large-volume LLNM (number of LLNMs >5) and low-volume LLNM (number of LLNMs ≤5). Risk factors of recurrence/persistence in PTC patients with N1b were analyzed. Preoperative ultrasound features of PTC with large-volume LLNM were analyzed. For the patients with a mean follow-up of 44.0 months, the risk of recurrence/persistence was 25.1% in PTC patients with N1b. The recurrence/persistence rate was significantly higher in patients with large-volume LLNM than in patients with low-volume LLNM by multivariate analysis (37.3% vs. 17.1%; HR = 2.451, 95% CI 1.41-4.261, p = 0.001). The 3-year and 5-year recurrence/persistence-free survival for those with large-volume LLNM were 93.2% and 47.2%, respectively. Moreover, we found that multilevel suspected LLNMs and loss of fatty hilum were independent preoperative indicative factors of large-volume LLNM (OR = 6.239, 95% CI 3.547-10.977, p < 0.001; OR = 5.149, 95% CI 1.859-14.261, p = 0.002). In conclusion, multilevel suspected LLNM and loss of fatty hilum on ultrasound tended to be more common in patients with large-volume LLNM. PTC patients with large-volume LLNM are at a higher recurrent/persistent risk than those with low-volume LLNM. Large-volume LLNM may be used to stratify the risk of recurrence/persistence in PTC.

Role of Postoperative Radiotherapy in Nonmetastatic Head and Neck Adenoid Cystic Carcinoma

BACKGROUND

Head and neck adenoid cystic carcinoma (ACC) is a rare malignant tumor that is prone to local recurrence. The NCCN Guidelines for Head and Neck Cancers recommend that all patients with ACC receive postoperative radiotherapy (PORT). However, whether PORT can improve local control and which patients can benefit from PORT are unknown. This study aimed to assess the role of PORT and provide individualized suggestions for postoperative therapy in patients with ACC.

PATIENTS AND METHODS

We retrospectively reviewed patients with nonmetastatic head and neck ACC who underwent surgery with or without PORT. Recursive partitioning analysis (RPA) was performed to categorize the patients and predict local recurrence-free survival (LRFS). The survival outcome was compared between non-PORT and PORT groups.

RESULTS

A total of 319 patients were included. PORT was identified as a prognostic factor for LRFS in univariate (P=.01) and multivariate analysis (P<.01). However, it did not improve distant metastasis-free survival, disease-free survival, or overall survival in univariate analysis. RPA categorized patients into 3 prognostic groups: low-risk (negative margin, T1-T2, primary location = major or minor salivary gland), intermediate-risk (negative margin, T1-T2, primary location = other locations instead of a major or minor salivary gland; negative margin, T3-T4; positive margin, without bone invasion), and high-risk (positive margin, with bone invasion). Significant LRFS improvements in the PORT group were observed among intermediate-risk (P<.01) and high-risk patients (P<.05). LRFS improvements among low-risk patients were relatively insignificant (P=.10).

CONCLUSIONS

PORT was shown to be a positive prognostic factor for improved LRFS in ACC. Furthermore, PORT could significantly improve LRFS in intermediate-risk and high-risk patients with ACC, but whether low-risk patients could benefit from PORT needs further study.

Prognosis of papillary thyroid cancer in patients with Graves' disease: a propensity score-matched analysis

Background

Patients with Graves’ disease (GD) are at a 2.5 times higher risk of developing thyroid cancer than the general population. Previous studies reported conflicting results about the prognosis of thyroid cancer concomitant with GD. This study aimed to investigate the effect of GD to the recurrence rates of papillary thyroid carcinoma (PTC).

Methods

We reviewed 3628 patients who underwent total thyroidectomy for PTC at the Ewha Womans University Medical Center from January 2006 to June 2014. Of those, 114 patients had non-occult PTC with concomitant GD. To reduce potential confounding effects and selection bias, we conducted 1:5 propensity score matching and analyzed the recurrence-free survival.

Results

Thyroid cancer in patients with GD showed lower rate of lymphatic invasion (1.8% vs. 6.7%; p = 0.037), microscopic resection margin involvement (0.9% vs. 5.8%; p = 0.024), and lymph node metastasis (29.8% vs. 37.3%; p = 0.001) than in patients without GD, respectively. During the median follow-up of 94.1 months, recurrence occurred in one patient (0.9%) with GD. After propensity score matching for adjusting clinicopathological features, 5-year recurrence-free survival was comparable between patients with GD and euthyroid patients (100% vs. 98.4%, p = 0.572). Both tumor size [hazard ratio (HR) 1.585, p < 0.001] and lymph node metastasis (HR for N1a 3.067, p = 0.024; HR for N1b 15.65, p < 0.001) were predictive factors for recurrence-free survival, while GD was not associated with the recurrence.

Conclusions

Our data suggest that GD does not affect the prognosis of PTC. Thyroid cancer in patients with GD is not more aggressive than in euthyroid patients.

Lymphovascular invasion and risk of recurrence in papillary thyroid carcinoma

BACKGROUND

Lymphovascular invasion (LVI) is an established adverse prognostic factor in many cancers, however, there are few studies assessing its significance in papillary thyroid carcinoma (PTC). We aimed to determine if LVI is an independent prognostic factor in PTC.

METHODS

We conducted a single institution retrospective analysis of 610 patients with PTC treated between 1987 and 2016. LVI was defined as the presence or absence of cancer cells in blood vessels and/or lymphatics on histopathology. Multivariate Cox regression analysis was used to evaluate the association between LVI and recurrence-free survival (RFS).

RESULTS

The study cohort included 481 (78.9%) females and 129 (21.1%) males, with a median age of 47.6 years and median follow-up of 3.4 years. LVI was present in 56 (9.2%) patients and was associated with nodal metastases (P < 0.001), extrathyroidal extension (P < 0.001), extranodal extension (P < 0.001), multifocality (P = 0.018) and microscopic positive margins (P < 0.001). On univariate analysis, LVI was associated with reduced RFS (hazard ratio (HR) 2.3; 95% confidence interval (CI) 1.3-4.3; P = 0.007). However, after adjusting for nodal stage (pN0, pN1a, pN1b) there was no association between LVI and RFS (HR 1.3; 95% CI 0.7-2.5; P = 0.398). Similar results were obtained in full multivariate models adjusting for additional prognostic factors (HR 1.2; 95% CI 0.6-2.4; P = 0.627).

CONCLUSION

LVI is strongly associated with other adverse prognostic factors in PTC, particularly the presence and extent of nodal metastases. However, after adjusting for these, LVI is not an independent predictor of recurrence.

Lymphovascular invasion of papillary thyroid carcinoma revisited in the era of active surveillance

INTRODUCTION

Lymphovascular invasion (LVI) is associated with disease recurrence and compromised survival in patients with thyroid cancer. Nonetheless, LVI is not identifiable on preoperative ultrasound or cytologic assessment. We aimed to explore the clinicopathological features associated with LVI.

PATIENTS AND METHODS

We conducted a retrospective review of our prospectively maintained database from 2009 to 2018. Multivariate analyses were performed to determine the associations between clinicopathological parameters and LVI. Generalized additive models were used to examine the nonlinear relationship between continuous variables and LVI.

RESULTS

A total of 795 patients were included in the analysis, and 174 (22%) had LVI. Patients' age (odds ratio [OR] = 0.982), tumor size (OR = 1.466), clinical lymphadenopathy (OR = 6.975), and advanced extrathyroidal extension (OR = 2.938) were independently associated with LVI. In the subset analysis of 198 patients with available genetic information, tumor size (OR = 1.599), clinical lymph node metastasis (OR = 3.657), and TERT promoter mutation (OR = 4.726) were predictive of LVI. Among 573 patients who had no clinical lymphadenopathy or advanced extrathyroidal extension, tumor size was the only predictor of LVI. Tumor size >1.5 cm had an increased risk of LVI based on the generalized additive model plot and receiver operating characteristic curve analysis.

CONCLUSION

Tumor size is positively associated with the risk of LVI in papillary thyroid cancer. To avoid delayed treatment in patients with LVI, a tumor size of 1.5 cm may be considered as the safe upper limit for active surveillance.

Nomogram Based on Shear-Wave Elastography Radiomics Can Improve Preoperative Cervical Lymph Node Staging for Papillary Thyroid Carcinoma

Background: Accurate preoperative prediction of cervical lymph node (LN) metastasis in patients with papillary thyroid carcinoma (PTC) provides a basis for surgical decision-making and the extent of tumor resection. This study aimed to develop and validate an ultrasound radiomics nomogram for the preoperative assessment of LN status. Methods: Data from 147 PTC patients at the Wuhan Tongji Hospital and 90 cases at the Hunan Provincial Tumor Hospital between January 2017 and September 2019 were included in our study. They were grouped as the training and external validation set. Radiomics features were extracted from shear-wave elastography (SWE) images and corresponding B-mode ultrasound (BMUS) images. Then, the minimum redundancy maximum relevance algorithm and the least absolute shrinkage and selection operator regression were used to select LN status-related features and construct the SWE and BMUS radiomics score (Rad-score). Multivariate logistic regression was performed using the two radiomics scores together with clinical data, and a nomogram was subsequently developed. The performance of the nomogram was assessed with respect to discrimination, calibration, and clinical usefulness in the training and external validation set. Results: Both the SWE and BMUS Rad-scores were significantly higher in patients with cervical LN metastasis. Multivariate analysis indicated that the SWE Rad-scores, multifocality, and ultrasound (US)-reported LN status were independent risk factors associated with LN status. The radiomics nomogram, which incorporated the three variables, showed good calibration and discrimination in the training set (area under the receiver operator characteristic curve [AUC] 0.851 [CI 0.791-0.912]) and the validation set (AUC 0.832 [CI 0.749-0.916]). The significantly improved net reclassification improvement and index-integrated discrimination improvement demonstrated that SWE radiomics signature was a very useful marker to predict the LN metastasis in PTC. Decision curve analysis indicated that the SWE radiomics nomogram was clinically useful. Furthermore, the nomogram also showed favorable discriminatory efficacy in the US-reported LN-negative (cN0) subgroup (AUC 0.812 [CI 0.745-0.860]). Conclusions: The presented radiomics nomogram, which is based on the SWE radiomics signature, shows a favorable predictive value for LN staging in patients with PTC.

Elective Central Compartment Lymph Node Dissection Does not Increase the Risk of Postoperative Hypoparathyroidism in Patients Treated for Differentiated Thyroid Cancer

Aim

The aim of this study was to compare the incidence of postoperative hypoparathyroidism in two groups of patients who were treated for differentiated thyroid cancer.

Methods

A retrospective analysis of 179 patients who were treated for differentiated thyroid cancer in our institution from January 2011 until December 2018 was performed. Only patients initially treated with total thyroidectomy and those who did not have preoperatively confirmed central compartment and lateral neck lymph node metastases were included in this study. Two main groups of patients were analysed. The patients who were treated with total thyroidectomy and elective central compartment lymph node dissection simultaneously were included in the first group. The patients who were treated only with total thyroidectomy were included in the second group. The rate of transitory and persistent postoperative hypoparathyroidism was compared between the two groups.

Results

A total of 117 patients (65.4%) underwent total thyroidectomy and elective central compartment lymph node dissection simultaneously (TT + CCLNd group). The remaining 62 patients (34.6%) underwent total thyroidectomy only (TT group). A total of 22.6% patients in the TT group developed postoperative hypoparathyroidism compared with 25.6% in the TT + CCLNd group. The rate of persistent hypoparathyroidism in the TT and TT + CCLNd groups was 3.2% and 6.0%, respectively. The difference in the rate of transient and persistent postoperative hypoparathyroidism was not statistically significant between the two groups. Within the TT + CCLNd group, 82.9% of patients underwent ipsilateral paratracheal lymph node dissection and 17.1% underwent bilateral paratracheal lymph node dissection. The rate of postoperative hypoparathyroidism was analysed in those two subgroups of patients and did not prove to be statistically significant.

Discussion

While its impact on the local recurrence rate is still controversial, elective central compartment lymph node dissection could be a great tool for selection of patients who could profit from adjuvant radioiodine treatment. On the other hand, central compartment lymph node dissection could potentially increase the risk of hypoparathyroidism due to involuntary injury to parathyroid glands and/or their blood supply. Our study did not find a statistically significant difference regarding postoperative hypoparathyroidism between patients who underwent central compartment lymph node dissection compared with patients who underwent total thyroidectomy only. Our data are not in accordance with some of the previously published studies.

Conclusion

Our results demonstrated that elective central compartment lymph node dissection is a safe procedure and does not significantly increase the risk of postoperative hypoparathyroidism when it is performed simultaneously with total thyroidectomy.

Clinicopathologic characteristics and outcomes of papillary thyroid carcinoma in younger patients

In the 7th edition of AJCC staging system, cervical lymph node metastases (LNM) in papillary thyroid carcinoma (PTC) is considered as a poorer prognostic indicator only in patients aged 45 years or older, but as a low-risk factor in patients younger than 45 years. The objective of this study is to investigate the influence of cervical LNM on prognostic outcomes of young patients (<45 years' old) with PTC.We carried out a retrospective analysis of 1896 PTC patients younger than 45 years' old at diagnosis, who were firstly treated in our department between January 2005 and December 2014. Clinicopathologic features, recurrences, disease-free survival (DFS) were recorded and analyzed.A total of 1896 consecutive patients were identified, comprising of 426 males and 1470 females after a median follow-up period of 40 months (3-129 months) from initial surgery to disease recurrence or to the end of follow-up. The rate of recurrence was 2.16% (n = 41). The DFS rates for a 1-year, 3-year, or 5-year team were 99.1%, 97.8%, or 97.4%, respectively. Univariate analysis showed that diagnosed age ≤30 years, tumor size >1.0 cm, extrathyroidal extension, multifocal lesions, lesions in bilateral lobes, central neck LNM, and lateral neck LNM were associated with a worse DFS. Multivariate analysis showed that only central neck LNM and lateral neck LNM were significant independent prognostic factors for DFS (P < .001). For patients with papillary thyroid microcarcinoma, cervical LNM were also identified as independent risk factors for DFS (P < .001).LNM have prognostic significance for DFS in PTC patients younger than 45 years. It indicated that PTC patients (<45 years old) with LNM, especially lateral neck LNM, were understaged by the 7th edition of AJCC staging system. Thus, radical resection of primary tumor and metastatic lymph nodes, frequent follow-up, and strict TSH suppression should be taken for young patients with PTC.

Preoperative Sonographic and Clinicopathological Predictors for Solitary Lateral Neck Node Metastasis in Papillary Thyroid Carcinoma: A Retrospective Study

Background

Cervical lymph node metastasis (LNM) is an independent risk factor for poor prognosis of papillary thyroid carcinoma (PTC), but the scope of PTC lateral neck dissection (LND) is controversial. Solitary lateral lymph node metastasis (SLNM) is a special type of PTC with lateral LNM. Currently, study on the preoperative clinical characteristics of SLNM has been seldomly reported. This study evaluated the preoperative characteristics for predicting the SLNM of PTC.

Methods

We included 391 patients diagnosed with PTC between May 2011 and July 2017. Among those patients, 44 had SLNM and 347 had multiple lateral neck node metastasis (MLNM). The clinicopathologic characteristics and other central lymph node metastasis risk factors were retrospectively analyzed.

Results

Univariate analysis revealed that age and tumor size (≤1 cm) were significantly correlated with SLNM. In ROC curve analysis, the optimal cutoff age of preoperative predictors for the prediction of SLNM was 46.5 years (AUC=0.623, 0.536–0.710). Besides, the frequency and mean number of CLNM was significantly less in the SLNM than MLNM group. The oval and round tumor shape and well-defined margin of the tumor were more common in the SLNM group (p =0.001; p=0.024, respectively). In addition, multivariate analysis revealed that age ≥47, capsular invasion, no extrathyroidal extension, with central lymph node metastases and irregular shape were independent SLNM predictors of PTCs (odds ratio 2.386, 0.173, 0.284, 0.239, 0.188; 95% CI 1.07–5.140, 0.058–0.840, 0.066–0.926, 0.091–0.437, 0.167–0.864, respectively).

Conclusion

This study supported that SLNM is more likely to happen in PTC patients with age ≥47 years, capsular invasion, no extrathyroidal extension, with central lymph node metastases and irregular shape. That denotes, selective single level neck dissection can be considered as an alternative to systemic lateral neck dissection in those patients.

Recurrence following hemithyroidectomy in patients with low- and intermediate-risk papillary thyroid carcinoma

BACKGROUND

This study evaluated the incidence, patterns and risk factors for recurrence after hemithyroidectomy in patients with low- and intermediate-risk papillary thyroid carcinoma (PTC), and verified the predictive role of the risk staging systems in current use.

METHODS

The clinicopathological characteristics and risk categories were analysed according to recurrence in patients who underwent hemithyroidectomy for low- and intermediate-risk conventional PTC, and were followed up for at least 24 months. Five risk staging systems were used to stratify risk: the 2015 American Thyroid Association (ATA) system; Age, Metastases, Extent and Size (AMES) system; Metastases, Age, Complete resection, Invasion and Size (MACIS) system; Grade, Age, Metastases, Extent and Size (GAMES) system; and the eighth AJCC system.

RESULTS

The study included 561 patients; 93·9 per cent of the study population (527 of 561) had a papillary thyroid microcarcinoma 1 cm or smaller in size. At a mean follow-up of 83 months, 25 patients (4·5 per cent) had recurrence; among these patients, 23 (92%) presented with a remaining thyroid lobe. Multifocality was significantly associated with recurrence in univariable and multivariable analyses (adjusted hazard ratio 3·16, 95 per cent c.i. 1·25 to 7·98; P = 0·015). Disease-free survival (DFS) varied according to multifocality (P = 0·010). The five risk staging systems were not associated with recurrence, and their Harrell's C-index ranged from 0·500 to 0·531. DFS rates did not differ between the risk categories in each system.

CONCLUSION

Although the recurrence rate after hemithyroidectomy in patients with low- and intermediate-risk PTC was low, meticulous follow-up focusing on the remaining thyroid lobe is needed for early detection and timely management of recurrence. The risk scoring systems in current use have no predictive role in these patients.

Oncological impact of hypothyroidism and levothyroxine supplementation following hemithyroidectomy in patients with papillary thyroid carcinoma

BACKGROUND

We aimed to evaluate the oncological impact of hypothyroidism and levothyroxine (LT) supplementation after hemithyroidectomy in patients with papillary thyroid carcinoma (PTC).

METHODS

We retrospectively examined 401 patients who underwent hemithyroidectomy for classic PTC and who were postoperatively followed-up with ≥3 thyroid function measurements for ≥24 months.

RESULTS

During 77.4 months of follow-up, 268/401 patients (66.8%) developed hypothyroidism and 19/401 patients (4.7%) showed recurrence. Recurrence rates did not differ between the euthyroidism and hypothyroidism development groups. Recurrence rates were significantly lower in the LT group than in the no-LT group, although mean postoperative thyroid-stimulating hormone (TSH) levels were not different between the two groups. Univariate and multivariate analysis showed that tumors sized >1 cm and lack of LT supplementation were significantly associated with recurrence.

CONCLUSIONS

Postoperative hypothyroidism development was not a risk factor for PTC recurrence after hemithyroidectomy. Nevertheless, LT supplementation reduced recurrence risk without suppressing TSH.

Prognostic implications of the BRAF-V600E mutation in papillary thyroid carcinoma based on a new cut-off age stratification

The BRAF-V600^E mutation is the most common and specific oncogenic event known in papillary thyroid carcinoma (PTC). However, it remains controversial whether there is an association between the BRAF-V600^E mutation and clinicopathologically aggressive characteristics of PTC. The purpose of the present retrospective study was to investigate the significance of the BRAF-V600^E mutation in predicting prognostic and aggressive clinicopathological characteristics according to a new age-based stratification. Clinical data and the BRAF-V600^E mutation status of 475 patients with PTC were downloaded from The Cancer Genome Atlas database. The association between BRAF-V600^E status and clinicopathological characteristics was analyzed by χ² test or Fisher's exact test. Recurrence-free survival rate (RFS) was analyzed using the Kaplan-Meier method. Aggressive clinicopathological factors associated with recurrence were analyzed by Cox multivariate regression. This study was conducted on 219 cases of patients with PTC with a known BRAF-V600^E mutational status. In the ≥55 years age group, BRAF-V600^E was found to be significantly associated with aggressive PTC characteristics, including tumor size, PTC subtype, radioactive iodine (RAI) dose, follow-up time, recurrence, recurrence risk stage, advanced T stage, advanced N stage and American Joint Committee on Cancer (III/IV) stage (all P<0.05). RFS was analyzed by the log-rank test and exhibited statistically significant differences in the ≥55 years group (P=0.041), but there was no significant difference in the <55 group (P=0.757), according to the BRAF-V600^E mutation status. The BRAF-V600^E gene was excluded from the recurrence Cox multivariate regression model. The BRAF-V600^E mutation was found to better predict aggressive and recurrent PTC based on age stratification with the cut-off age of 55 years. The synergistic interaction between BRAF-V600^E mutation and the new age stratification may help clinicians reach the optimal decision in terms of surgical approach and the extent of surgery.

Individualized Prediction Of Metastatic Involvement Of Lymph Nodes Posterior To The Right Recurrent Laryngeal Nerve In Papillary Thyroid Carcinoma

Purpose

We aimed to establish a prediction model based on preoperative clinicopathologic features and intraoperative frozen section examination for precise prediction of metastatic involvement of lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) in patients with papillary thyroid carcinoma (PTC).

Methods

Clinicopathologic data pertaining to patients with PTC who underwent initial thyroid surgery between July 2015 and December 2017 were collected from electronic medical records. Multivariate logistic regression analysis was performed to identify independent predictors of LN-prRLN metastasis for incorporation in the nomogram. The performance of the model was assessed using discriminative ability, calibration, and clinical application.

Results

A total of 592 patients were enrolled in this study. The LN-prRLN metastatic positivity was 19% (95% confidence interval [CI], 15.61–21.89%). On multivariate analysis, ultrasonography-reported LN status, extrathyroid extension, Delphian lymph node metastasis, and number of metastatic pretracheal and paratracheal lymph nodes were independent predictors of LN-prRLN metastasis. The nomogram showed good discriminative ability (C-index: 0.87; [95% CI, 0.84–0.91]; bias-corrected C-index: 0.86 [through bootstrapping validation]) and was well calibrated. The decision curve analysis indicated potential clinical usefulness of the nomogram.

Conclusion

This study demonstrates that the risk of LN-prRLN metastasis in individual patients can be robustly predicted by a nomogram that integrates readily available preoperative clinicopathologic features and intraoperative frozen section examination. The nomogram may facilitate intraoperative decision-making for patients with PTC.

Right posterior paratracheal lymph nodes metastasis is one of the predictive factors in right-sided papillary thyroid carcinoma

BACKGROUND

Lymph nodes in the right paratracheal region are separated as anterior and posterior on the basis with right recurrent laryngeal nerve. Dissection of the right posterior paratracheal lymph nodes is sometimes overlooked during a central neck dissection. Therefore, this study was designed to assess the clinicopathologic risk factors and prognostic implication for recurrence related to the presence of right posterior paratracheal lymph nodes metastasis in patient with right-sided papillary thyroid carcinoma.

METHODS

Records from 763 patients with papillary thyroid carcinoma who underwent total thyroidectomy with central neck dissection, including the right posterior paratracheal lymph nodes, between January 2007 and March 2015 were reviewed retrospectively.

RESULTS

Among 763 patients (120 men and 643 women; mean age 49.04 years) with right-sided papillary thyroid carcinoma, 127 exhibited right posterior paratracheal lymph nodes metastases. In multivariate analysis, central-compartment lymph nodes metastases (odds ratio 5.203; 95% confidence interval, 2.864-9.453) and lateral cervical lymph nodes metastases (odds ratio 3.668; 95% confidence interval, 2.375-5.667) were independently correlated with right posterior paratracheal lymph nodes metastases. Twenty-three patients (3.0%) showed loco-regional recurrence. The loco-regional recurrence rate was greater in the groups for males (P = .012), larger tumor size (>10 mm; P = .044), extrathyroidal extention (P = .002), and right posterior paratracheal lymph nodes metastasis (P < .001).

CONCLUSION

Right posterior paratracheal lymph nodes metastases are predictive factors of loco-regional recurrence, and these lymph nodes should be removed completely during a right central neck dissection in patients with right-sided papillary thyroid carcinoma with central or lateral cervical lymph node metastasis.

Microscopically positive surgical margins and local recurrence in thyroid cancer. A meta-analysis

BACKGROUND

Microscopically positive surgical margins are a prognostic factor of recurrence in advanced thyroid carcinoma. However, information on early and completely resected thyroid tumors is scarce. Some studies do not identify any association between positive margin and local recurrence. The objective of this study was to perform a meta-analysis to measure the association of microscopically positive surgical margins and local recurrence in patients who underwent total thyroidectomy.

METHODS

Clinical trials assessing the association between microscopically positive surgical margin and local recurrence in patients with early-stage, well-differentiated thyroid carcinoma who underwent total thyroidectomy were evaluated. The outcome measured was local recurrence in the thyroid bed. A systematic review and meta-analysis was done using a random-effects model.

RESULTS

Six studies with 7696 patients were identified. Methodological quality was good, and we did not identify statistical heterogeneity or publication bias. The risk difference for microscopically positive surgical margin and local recurrence was 0% (95% CI 0 to 1).

CONCLUSION

Meta-analysis did not find a statistically significant association between microscopically positive surgical margin and local recurrence in this population. A finding of microscopically positive surgical margin in the absence of other adverse factors is not an indication for adjuvant treatment.

The role of two tumor foci for predicting central lymph node metastasis in papillary thyroid carcinoma: A meta-analysis

BACKGROUND AND OBJECTIVE

Two tumor foci are the most common in multifocal papillary thyroid carcinoma, but whether they should be regarded as the indicator of central lymph node metastasis remains unclear. To investigate the role of two tumor foci for predicting central lymph node metastasis, we performed a meta-analysis of published studies.

METHODS

We performed a systematic literature search of PubMed, Embase and Web of Science prior to September 29, 2017. The relevant articles were examined and the eligible studies were included to assess the metastatic risk of central lymph node in papillary thyroid carcinoma with one, two and more than two (>2) tumor foci.

RESULTS

Five eligible studies included 4045 patients in this meta-analysis. Two tumor foci were the most common in multifocal papillary thyroid carcinoma (63.8%, 939/1471). Multifocality group showed a higher risk of central lymph node metastasis compared with unifocality group (odds ratio: 1.58, 95% confidence interval: 1.37-1.81). The risk of central lymph node metastasis was higher in two tumor foci group than unifocality group (odds ratio: 1.38, 95% confidence interval: 1.17-1.62). However, this risk in two tumor foci group was lower than >2 tumor foci group (odds ratio: 0.62, 95% confidence interval: 0.42-0.92). Begg's test revealed no obvious publication bias.

CONCLUSION

This meta-analysis suggested that two tumor foci should be regarded as the predictive factor of central lymph node metastasis, but the role of it was less important than three or more than three tumor foci. Understanding the role of two tumor foci for predicting central lymph node metastasis may help clinicians make an optimal decision of treatment and the extent of surgery for multifocal papillary thyroid carcinoma.

The synergic effect of BRAFV600E mutation and multifocality on central lymph node metastasis in unilateral papillary thyroid carcinoma

The purpose of this study is to evaluate the potential synergic effect of BRAF^V600E mutation and multifocality on central lymph nodes metastasis (CLNM) in the patients with unilateral papillary thyroid carcinoma (PTC). We enrolled 413 patients with unilateral PTCs who accepted prophylactic unilateral or bilateral central lymph node dissection (LND). Univariate and multivariate analyses were made to determine the association between related factors and CLNM. Then, all patients were divided into 4 groups based on their status of BRAF^V600E mutation and multifocality. Relative excess risk of interaction (RERI), attributable proportion (AP) of interaction and synergy index (SI) were applied to evaluate the interactive effect of these two factors on CLNM. Results showed that BRAF^V600E mutation and multifocality were independent risk factors for CLNM. A further study revealed that unilateral PTCs accompanying multifocality with BRAF^V600E mutation had the highest incidence of CLNM compared with other subgroups. Besides, RERI was 4.323 (95% CI = 1.276-7.369), AP was 0.523 (95% CI = 0.364-0.682) and SI was 2.469 (95% CI = 1.607 to 3.794), indicating a significant additive interaction of BRAF^V600E mutation and multifocality on CLNM. The present study has confirmed that BRAF^V600E mutation and multifocality are risk factors for CLNM in unilateral PTC. Additionally, unilateral PTC patients accompanying multifocality with BRAF^V600E mutation may have an increased risk of CLNM in clinically negative CLNM.

Prognostic impact of vascular invasion in differentiated thyroid carcinoma: a systematic review and meta-analysis

BACKGROUND

The role of vascular invasion (VI) as a prognostic marker in thyroid cancer is continuously debated among investigators. In this systematic review and meta-analysis, we aimed to investigate the association of VI with tumor recurrence and patient mortality in differentiated thyroid cancers (DTCs).

METHODS

We searched five electronic databases for cases of DTC matching our criteria. Data of tumor persistence, locoregional recurrence (LRR), distant recurrence (DR) and overall recurrence/persistence (RP) were extracted and pooled into odds ratios (OR) and corresponding 95% confidence intervals (CIs) using random effect model. Pooled hazard ratio (HR) for disease-specific survival (DSS) was calculated using random effect model weighted by inverse variance method. Publication bias was examined by using Egger's test and funnel plot.

RESULTS

From 1650 studies, we included 26 studies comprising 11 961 DTCs for meta-analyses. In DTC patients, we found significant associations of VI with tumor persistence (OR = 2.75; 95% CI = 1.46-5.18), LRR (OR = 4.44; 95% CI = 2.94-6.71), DR (OR = 5.08; 95% CI = 2.95-8.75), overall RP (OR = 3.53; 95% CI = 2.09-5.96) and worse DSS (HR = 2.47; 95% CI = 1.45-4.21). Our results also demonstrated that the presence of extensive VI is associated with a significantly higher risk for DR in follicular thyroid carcinomas as compared with focal VI.

CONCLUSION

Our study demonstrated a significant impact of VI on tumor recurrence and patient survival in DTC patients. The presence and extent of VI should be considered an adverse prognostic factor in DTCs.

BRAFV600E mutation is not associated with central lymph node metastasis in all patients with papillary thyroid cancer: Different histological subtypes and preoperative lymph node status should be taken into account

The association between central lymph node metastasis (LNM) and risk factors, including the presence of the BRAF mutation, BRAF^V600E, in patients with papillary thyroid cancer (PTC) requires further investigation. A potent risk factor that can indicate LNM in different histological subtypes of PTC and in different preoperative central lymph node statuses also requires further research. A total of 287 patients with PTC who accepted thyroidectomy were included in the present study. Clinicopathological data of these patients were reviewed to examine the risk factors for central LNM through univariate and multivariate analyses. Overall, BRAF^V600E in patients with cN0 (subclinical nodal disease) and cN1 (other than cN0) PTC was associated with central LNM. However, multivariate analyses demonstrated that BRAF^V600E was not an independent risk factor in patients with cN1 or cN0 PTC. For patients with classical variant PTC (CVPTC), BRAF^V600E was independently associated with central LNM. However, on further analysis, the association was only significant in patients with cN0 CVPTC. For patients with follicular variant PTC (FVPTC) or aggressive variant PTC (AVPTC), the BRAF^V600E mutation rate was not significantly different between patients with and without central LNM. In conclusion, BRAF^V600E was an independent risk factor for central LNM overall in patients with PTC and in patients with CVPTC, particularly in patients with cN0 CVPTC. However, BRAF^V600E was not an independent risk factor for patients with FVPTC and AVPTC. Therefore, BRAF^V600E provides varied clinical significance in different histological subtypes and preoperative central lymph node status.

Dynamic monitoring of circulating microRNAs as a predictive biomarker for the diagnosis and recurrence of papillary thyroid carcinoma

Circulating microRNAs (miRNAs/miRs) are considered to be potential biomarkers for numerous types of cancer. However, previous investigations into the expression of miRNAs in the serum of patients with papillary thyroid carcinoma (PTC) to predict diagnosis, prognosis and recurrence have reported conflicting results, and the role of miRNAs remains unclear. The present study dynamically assessed the circulating miRNA profile in patients with PTC and determined whether miRNAs in the serum could be used as biomarkers for the diagnosis, prognosis and recurrence of PTC. The expression levels of 3 reportedly upregulated miRNAs (miR-222, miR-221 and miR-146b) were analyzed using reverse transcription-quantitative polymerase chain reaction in 106 patients with PTC, 35 patients with benign thyroid nodules (BTN) and 40 paired controls. Patients with either newly diagnosed PTC or BTN who were undergoing thyroidectomies were recruited for a dynamic analysis of preoperative and postoperative serum miRNA levels. The results indicated that the expression levels of serum miR-222, miR-221 and miR-146b were significantly increased in patients with newly diagnosed PTC compared with controls and patients with BTN. Receiver operating characteristic curve analysis indicated that these miRNAs had a high diagnostic sensitivity and specificity for PTC prior to surgery. The expression of these three miRNAs in serum was significantly associated with poorer prognostic variables, including extrathyroidal invasion, metastatic lymph nodes and high-risk or advanced tumor node metastasis stage. More notably, the present study identified 2.36-, 2.69- and 5.39-fold reductions in the serum levels of miR-222, miR-221 and miR-146b, respectively, subsequent to patients undergoing a thyroidectomy. In addition, miR-222, miR-221 and miR-146b were overexpressed in the PTC with recurrence group compared with the PTC without recurrence group. Collectively, dynamic monitoring of circulating miRNAs may serve as a non-invasive biomarker for the diagnosis of PTC and the postoperative monitoring of its progression and recurrence.

Practical Performance of the 2015 American Thyroid Association Guidelines for Predicting Tumor Recurrence in Patients with Papillary Thyroid Cancer in South Korea

BACKGROUND

The 2015 American Thyroid Association (ATA) management guidelines for adult patients with differentiated thyroid cancer propose the use of the modified initial risk stratification and response to therapy re-stratification systems. This study was conducted to validate the practicality of the revised guidelines for predicting tumor recurrence in patients with differentiated thyroid cancer.

METHODS

Patients with papillary thyroid cancer (n = 2425) who underwent total thyroidectomy with central neck node dissection with or without modified radical neck node dissection at a single institution between October 1985 and July 2009 were retrospectively enrolled. The accuracy of three different risk-stratification strategies for predicting disease-free survival, set out in the 2009 and 2015 ATA management guidelines, was assessed: the initial risk stratification (ATA 2009-RSS), the modified initial risk stratification (ATA 2015-RSS), and the response to therapy re-stratification (ATA 2015-RTR).

RESULTS

After applying the ATA 2015-RSS, 258/1913 (13.5%) of patients originally designated as intermediate risk by the ATA 2009-RSS were designated as low risk. This was mainly due to the small number of metastatic lymph nodes. Recurrence was detected in 136 (5.6%) patients during follow-up. Of the 2425 cases examined, 375 were designated as low risk by the ATA 2009-RSS, with a recurrence rate of 1.1%. However, the ATA 2015-RSS designated 633 (26.1%) cases as low risk, with a recurrence rate of 0.9%. Implementing the ATA 2015-RTR predicted an excellent response in 1597 (65.9%) cases, with a recurrence rate of 1.1%. According to the proportion of variance explained (PVE), the Akaike information criterion, Harrell's c index, and integrated area under the curve, comparing the predictive accuracy of the ATA 2009-RSS, ATA 2015-RSS, and ATA 2015-RTR revealed that the ATA 2015-RTR was a superior predictor of recurrence.

CONCLUSIONS

A proportion of patients designated as intermediate risk by the ATA 2009-RSS were designated as low risk by the ATA 2015-RSS. The ATA 2015-RTR may be the most accurate predictor of risk of recurrence.

MiR-221, a potential prognostic biomarker for recurrence in papillary thyroid cancer

Background

Many studies have reported several transcriptionally deregulated microRNAs (miRNAs) in papillary thyroid cancer (PTC) tissue in comparison with benign thyroid nodules and normal thyroid tissues. However, the correlation between miRNA expressions and PTC recurrence still remains unclear.

Methods

The PTC patients who scheduled to undergo total thyroidectomy by the same surgical team in Ningbo NO.2 Hospital from March 1998 to March 2008 were enrolled in this study. The clinical and pathological characteristics of each patient were recorded in detail. The selected miRNA expressions were detected using quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Potential predictive factors for cancer recurrence were evaluated by univariate and multivariate Cox proportional hazard analysis.

Results

A total of 78 patients were enrolled with 49 females at a mean age of 45.8 years. Enrolled patients were divided into two groups: nonrecurrent group (n = 54) and recurrent group (n = 24). The results from the univariate Cox proportional hazard analysis revealed that primary tumor size, TNM stage, extrathyroid extension, miR-221, and miR-222 expressions were significantly associated with PTC recurrence (P < 0.05). The tissue expression of miR-221 was the only independent risk factor for PTC recurrence (HR 1.41; 95%CI 1.14–1.95, P = 0.007) by multiple Cox proportional hazard analysis.

Conclusions

This study identified the potential role of miR-221 as a prognostic biomarker for the recurrence in PTC.

Intraoperative Real-Time Localization of Normal Parathyroid Glands With Autofluorescence Imaging

CONTEXT

This biomedical investigation is valuable for identification and localization of parathyroid glands during thyroidectomy, which can provide an intraoperative real-time visual guidance.

OBJECTIVE

The objective of the study was to investigate the feasibility of real-time autofluorescence imaging of the parathyroid glands without exogenous contrast dye for their localization and demonstration of relation to the background tissues.

SETTING

This research was undertaken at Kosin University Gospel Hospital.

METHODS

Sixteen normal parathyroid glands from eight patients with papillary thyroid carcinoma were enrolled. Photo images of the surgical field including the parathyroid and background tissues were taken with a digital camera, 780 nm light-emitting diode to excite the parathyroid, and infrared illuminator to visualize the entire neck. The area-averaged autofluorescence intensity of parathyroid over the area-averaged fluorescence intensity of background tissues was measured.

MAIN OUTCOME MEASURE

The location of the parathyroid gland was verified with a single image.

RESULTS

The area-averaged autofluorescence intensity of parathyroid over the area-averaged fluorescence intensity of background tissues for all parathyroid glands was higher than 1, with a minimum of 1.95 and a maximum of 5.20 (average 2.76, SD 0.79). By our technique, all 16 parathyroid glands were detected (positive predictive value of 100%), and the entire surgical field including the parathyroid and background tissues was visualized as well. The parathyroid glands that were exposed or even covered by connective tissues or blood vessels could be detected with strong emission.

CONCLUSIONS

This method showed the precise localization of the parathyroid glands and demonstrated their relation to background tissue. We believe that this simple, nonexogenous dye technique of anatomical guidance can aid surgeons to preserve parathyroid glands during thyroidectomy.

WITHDRAWN: Serum miRNA-203 expression, a potential biomarker for recurrence and prognosis in papillary thyroid carcinoma

Ahead of Print article withdrawn by publisher.

The thyroid imaging reporting and data system on US, but not the BRAFV600E mutation in fine-needle aspirates, is associated with lateral lymph node metastasis in PTC

The majority of patients with papillary thyroid carcinoma (PTC) have an excellent prognosis, but some show poorer outcomes and would benefit from adjunctive prognostic tools. The B-Raf proto-oncogene, serine/threonine kinase (BRAF) mutation, either based on both its presence or its quantitative measurement, and ultrasound (US) features may serve as a prognostic marker. The aim of this study was to investigate (1) the association between clinical-pathologic prognostic factors and the BRAF mutation found in fine-needle aspirates, based on both its presence and its corresponding cycle threshold (Ct) value, and (2) the association between prognostic factors and suspicious US features classified by the thyroid imaging reporting and data system (TIRADS) in PTC.Two-hundred fifty-eight consecutive patients with PTC > 1 cm and who underwent preoperative US-guided fine-needle aspiration were included in this retrospective study. Clinical-pathologic variables were compared between patients with and without the BRAF mutation. Multivariate analyses were performed to investigate (1) the association between clinical-pathologic prognostic factors and the BRAF mutation found in fine-needle aspirates, based on both its presence and corresponding Ct values, and (2) the association between prognostic factors and suspicious TIRADS US features.BRAF-positive patients had a higher proportion of multiple tumors (P = 0.017). The number of suspicious US features classified by the TIRADS was an independent factor for predicting lateral lymph node metastasis, both in all 258 patients (odds ratio [OR] = 1.902, P = 0.005) and in 214 BRAF-positive patients (OR = 1.686, P = 0.037). The BRAF mutation status or BRAFCt values were not associated with any of the clinical-pathologic prognostic factors.In conclusion, a higher number of suspicious US features classified by the TIRADS, but not the BRAF mutation, are associated with lateral lymph node metastasis in patients with PTC, and can aid in the preoperative identification of patients at increased risk of lateral lymph node metastasis.

Soft tissue invasion of papillary thyroid carcinoma

Extrathyroidal extension (ETE) of papillary thyroid carcinoma (PTC) is common and clinical presentation can vary from minimal to extensive locoregional involvement. Although PTC is generally considered the most benign among all thyroid carcinomas, it may present with local invasion with poor prognosis. Our retrospective study involved 3267 PTC patients undergoing regular follow-up at Chang Gung Medical Center in Linkou, Taiwan. Among them, 269 were PTC cases with ETE, having tumors greater than 1 cm in size and treated with total or complete thyroidectomy with or without lymph node dissection for which the follow-up period was over 10 years. The mean age of 269 cases was 46.8 ± 15.1 (range 11-83 years) years. The number of females was 204 (75.8 %). Patients were categorized into minimal ETE (175 cases) and extensive ETE (94 cases) groups according to surgical findings and pathological reports. Mean follow-up period was 13.3 ± 5.5 (range 0.2-29.3) years, during which 28 (10.4 %) patients died of thyroid cancer; and 63 (23.4 %) of all-cause mortality. Multivariate analysis showed that age, gender, extensive ETE, and lymph node metastasis had a statistically significant effect on thyroid cancer mortality. Survival rates were significantly different between minimal ETE and extensive ETE groups (p < 0.0001). In conclusion, perithyroidal soft tissue involvement by PTC is an important factor that determines patient prognosis and a closer follow-up and more aggressive treatment is necessary for patients who are old, male, extensive ETE, and with lymph node involvement.

Prophylactic central lymph node dissection in cN0 patients with papillary thyroid carcinoma: A retrospective study in China

OBJECTIVE

The objective of the study was to assess the patterns of central cervical lymph node metastasis (CLNM) and evaluate the prophylactic central lymph node dissection (CLND) in papillary thyroid carcinoma (PTC) patients without clinical positive lymph nodes.

METHODS

We retrospectively reviewed 1555 patients with PTC between 2003 and 2008. Lymph node metastatic risk factors and the pattern of lymph node metastasis in PTC were studied using multivariate analysis.

RESULTS

Male patients, aged ≤ 45 years, the presence of extrathyroidal extension, and a primary tumor size > 10 mm were identified as risk factors for CLNM with odds ratios of 2.089, 2.417, 1.534, and 3.079, respectively. Among 1555 patients, 97 cases (6.24%) had transient hypoparathyroidism, and only two patients (0.13%) had permanent hypoparathyroidism. Recurrent laryngeal nerve injury after thyroidectomy occurred in 14 patients (0.9%). In this group, nine cases were transient injury and the remaining five were permanent. During the period of follow-up, ranging from 5 years to 10 years, 18 patients (1.16%) were found with locoregional recurrence.

CONCLUSION

Taken together, in terms of the high incidence rate of CLNM in cN0 PTC patients, we believe that routine prophylactic CLND is optimal for clinically negative PTC patients, during their first treatment, especially for those with risk factors for CLNM.