Predictors of metastasis to lymph nodes posterior to the right recurrent laryngeal nerve in differentiated thyroid carcinoma: A prospective study

Prediction of papillary thyroid metastases to the central compartment: proposal of a model taking into consideration other thyroid conditions

Objective

To construct risk prediction models for cervical lymph node metastasis (CLNM) of papillary thyroid carcinoma (PTC) under different thyroid disease backgrounds and to analyze and compare risk factors among different groups.

Methods

This retrospective study included 518 patients with PTC that was pathologically confirmed post-operatively from January 2021 to November 2021. Demographic, ultrasound and pathological data were recorded. Univariate and multivariate logistic regression analyses were performed to identify factors associated with CLNM in the whole patient cohort and in patients grouped according to diagnoses of Hashimoto's thyroiditis (HT), nodular goiter (NG), and no background disease. Prediction models were constructed for each group, and their performances were compared.

Results

Analysis of the whole PTC patient cohort identified NG as independently associated with CLNM. The independent risk factors for patients with no background disease were the maximum thyroid nodule diameter and American College of Radiology Thyroid Imaging Reporting & Data System score; those for patients with HT were the maximum thyroid nodule diameter, ACR TI-RADS score, and multifocality; and those for patients with NG were the maximum thyroid nodule diameter, ACR TI-RADS score, multifocality and gender.

Conclusion

Background thyroid disease impacts CLNM in PTC patients, and risk factors for CLNM vary among PTC patients with different background diseases. Ultrasound is useful for diagnosing background thyroid disease, which can inform treatment planning. Different prediction models are recommended for PTC cases with different thyroid diseases.

Multimodal predictive factors of metastasis in lymph nodes posterior to the right recurrent laryngeal nerve in papillary thyroid carcinoma

Objective

The lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) is a crucial component of the central lymph nodes (LNs). We aimed to evaluate multimodal predictive factors of LN-prRLN metastasis in patients with papillary thyroid carcinomas (PTCs), including the clinical data, pathologic data, and preoperative sonographic characteristics of PTCs.

Methods

A total of 403 diagnosed PTC patients who underwent unilateral, sub-total, or total thyroidectomy with central neck dissection were enrolled in this retrospective study. The clinical data, pathologic data, conventional ultrasound (US) and contrast-enhanced ultrasound (CEUS) characteristics of PTCs were collected and evaluated for predicting LN-prRLN metastasis.

Results

In this study, 96 PTC patients with LN-prRLN metastasis and 307 PTC patients without LN-prRLN metastasis were included. Univariate analysis demonstrated that PTC patients with LN-prRLN metastasis more often had younger age, larger size, multifocal cancers, A/T < 1, well-margins, microcalcification, petal-like calcification, internal vascularity, centripetal perfusion pattern and surrounding ring enhancement. Multivariate logistic regression analysis revealed that the CEUS centripetal perfusion pattern, central LN detected by ultrasound and LN-arRLN metastasis were independent characteristics for predicting LN-prRLN metastasis in PTC patients.

Conclusion

According to our research, it is essential for clinicians to thoroughly dissect central LNs, particularly LN-prRLNs.

Construction and Validation of a Predictive Nomogram Based on Ultrasound for Lymph Node Metastasis of Papillary Thyroid Carcinoma in the Cervical Central Region

ABSTRACT

To establish and validate a nomogram for predicting lymph node metastasis (LNM) of papillary thyroid carcinoma (PTC) in the cervical central region. This retrospective study included 287 PTC patients with 309 nodules treated from December 2018 to May 2020 at our hospital. The cohort was divided randomly into a training set and a testing set according to a 7:3 ratio. The training set contained 216 nodules, and the testing set contained 93 nodules. The nomogram was developed using the training set, and the data of the testing set were used to validate the performance of nomogram. The predictive accuracy and discriminative ability of the nomogram were determined by concordance index (C-index) and calibration curve. The study showed multifocality, thyroid lesion size, and American College of Radiology Thyroid Imaging, Reporting and Data System (TI-RADS) score were significantly independently associated with LNM in the cervical central region. In the testing set, the calibration curve showed that the nomogram had good discrimination with a C-index of 0.775 (95% confidence interval, 0.680-0.869) and adequate calibration ( P = 0.808). By decision curve analysis and clinical impact curve analysis, the nomogram was shown to have a satisfactory net benefit between thresholds of 0.40 and 0.75. The nomogram can be used for predicting LNM of PTC in the cervical central region and may provide valuable guidance for planning the surgical treatment of PTC patients.

Lymph Node Posterior to the Right Recurrent Laryngeal Nerve Metastasis in Right Lobe T1a Papillary Thyroid Carcinoma: A Retrospective Cohort Study

INTRODUCTION AND OBJECTIVES

This study analyzed the incidence and predictors of lymph node posterior to the right recurrent laryngeal nerve metastasis in T1a papillary thyroid carcinoma of the right lobe.

METHODS

This was a retrospective cohort study. Patients were selected from those who had received surgical treatment for primary papillary thyroid carcinoma between January 2019 and December 2020. The association between clinicopathologic variables and lymph node posterior to the right recurrent laryngeal nerve metastasis was assessed using univariate and multivariate analyses. Postoperative complications were also described.

RESULTS

Lymph node posterior to the right recurrent laryngeal nerve metastasis was present in 6.0% of the 402 study patients. It was the most likely to occur when there were other lymph node metastases, particularly in the lymph node anterior to the recurrent laryngeal nerve. Independent predictors for lymph node posterior to the right recurrent laryngeal nerve metastasis were a tumor size of ≥5.0 mm, a lower pole location, and lymph node anterior to the right recurrent laryngeal nerve metastasis. The rate of persistent vocal cord paralysis was .5%, and no patient developed permanent hypoparathyroidism.

CONCLUSIONS

Although lymph node posterior to the right recurrent laryngeal nerve metastases of the right lobe T1a papillary thyroid carcinoma is uncommon, the possibility of metastasis should be investigated when there is a positive lymph node anterior to the right recurrent laryngeal nerve in a tumor >5.0 mm in size located in the lower pole. Lymph node posterior to the right recurrent laryngeal nerve dissection is recommended for such tumors.

Pattern and Predictive Factors of Metastasis in Lymph Nodes Posterior to the Right Recurrent Laryngeal Nerve in Papillary Thyroid Carcinoma

OBJECTIVE

The right cervical central lymph nodes include lymph nodes anterior to the right recurrent laryngeal nerve (LN-arRLN) and lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN), and are separated by the right recurrent laryngeal nerve (RLN). LN-prRLN is a common site of nodal recurrence after the resection of papillary thyroid carcinoma (PTC). However, the complexity in anatomical structure brings difficulties in determining the surgical scope, so it is necessary to assess the pattern and predictive factors of right cervical central lymph nodes, especially LN-prRLN metastasis in papillary thyroid carcinoma.

METHODS

A total of 562 diagnosed PTC patients who underwent right or total thyroidectomy were enrolled in this retrospective study. The clinicopathological features were collected, univariate and multivariate analyses were performed to determine predictive factors of the right central lymph node metastasis.

RESULTS

In this study, the metastatic rates of the right CLN, the LN-arRLN and the LN-prRLN were 59.6% (335/562), 51.8% (291/562) and 30.4% (171/562), respectively. And 22.6% (127/562) of patients had both LN-arRLN and LN-prRLN metastasis. Among patients without LN-arRLN metastasis, the rate of LN-prRLN metastasis was 16.2% (44/271), accounting for 25.7% of the LN-prRLN metastasis group. Factors associated with an increased risk of LN-arRLN metastasis include male, age below 55 years, tumor size > 1cm, extrathyroidal extension (ETE), clinical lymph nodes metastasis(cN1), lateral lymph node metastasis, and left CLN metastasis. In addition, ETE, lateral lymph node metastasis, and LN-arRLN metastasis were independent factors of LN-prRLN metastasis. The predictive factors of LN-prRLN in cN0 PTC were further explored, revealing that tumor size ≥1.5cm, ETE, and LN-arRLN metastasis were independent predictors of LN-prRLN metastasis in cN0 PTC.

CONCLUSION

The LN-prRLN should not be ignored in surgery because of its high rate of metastasis. Our findings indicate that thorough dissection of central lymph nodes, especially LN-prRLN is crucial in clinical work.

Unnecessity of Routine Dissection of Right Central Lymph Nodes in cN0 Papillary Thyroid Carcinoma Located at the Left Thyroid Lobe

Objective

The lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) is an important part of the central lymph nodes (LNs). We aimed to explore the rate and predictors of LN-prRLN metastasis in cN0 papillary thyroid carcinoma (PTC) located at the left thyroid lobe.

Methods

Patients with surgically treated primary left lobe PTC were retrospectively enrolled. The metastatic distribution of LN-prRLN and postoperative complications were assessed. The association between LN-prRLN metastasis and clinicopathological variables was evaluated by univariate and multivariate analyses.

Results

A total of 857 patients were included for the analysis. Central LN metastasis was noted in 310 (35.3%) cases. The most (27.6%) and least (1.7%) commonly involved LNs were the left paratracheal LN and the LN-prRLN. In the univariate analysis, the tumor size, multifocality, the extent of extrathyroidal extension (none vs. macroscopic vs. macroscopic maximal), and perineural invasion were associated with positive LN-prRLN. In the multivariate analysis, tumor size of >40.0 mm and macroscopic maximal invasion were found as the only two independent predictors. Transient and permanent hypoparathyroidism were noted in 90 (10.2%) and 13 (1.5%) patients, respectively. Voice change was noted in 40 (4.6%) patients, and 20 patients recovered.

Conclusions

In cN0 PTC located at the left lobe, LN-prRLN metastasis was very uncommon. We found that LN-prRLN dissection is not required routinely, but should be performed if the tumor size is >40.0 mm and macroscopic maximal extrathyroidal extension is present.

Dynamic Nomogram for Predicting Lateral Cervical Lymph Node Metastasis in Papillary Thyroid Carcinoma

OBJECTIVE

To establish a dynamic nomogram based on preoperative clinical data for prediction of lateral lymph node metastasis (LLNM) of papillary thyroid carcinoma.

STUDY DESIGN

Retrospective study.

SETTING

The Sixth Affiliated Hospital of Sun Yat-Sen University.

METHODS

The data of 477 patients from 2 centers formed the training group and validation group and were retrospectively reviewed. Preoperative clinical factors influencing LLNM were identified by univariable and multivariable analysis and were to construct a predictive dynamic nomogram for LLNM. Receiver operating characteristic analysis and calibration curves were used to evaluate the predictive power of the nomogram.

RESULTS

The following were identified as independent risk factors for LLNM: male sex (odds ratio [OR] = 4.6, P = .04), tumor size ≥10.5 mm (OR = 7.9, P = .008), thyroid nodules (OR = 6.1, P = .013), irregular tumor shape (OR = 24.6, P = .001), rich lymph node vascularity (OR = 9.7, P = .004), and lymph node location. The dynamic nomogram constructed with these factors is available at https://zxh1119.shinyapps.io/DynNomapp/. The nomogram showed good performance, with an area under the curve of 0.956 (95% CI, 0.925-0.986), a sensitivity of 0.87, and a specificity of 0.91, if high-risk patients were defined as those with a predicted probability ≥0.3 or total score ≥200. The nomogram performed well in the external validation cohort (area under the curve, 0.915; 95% CI, 0.862-0.967).

CONCLUSIONS

The dynamic nomogram for preoperative prediction of LLNM in papillary thyroid carcinoma can help surgeons identify high-risk patients and develop individualized treatment plans.

Carbon nanoparticle-guided intraoperative lymph node biopsy predicts the status of lymph nodes posterior to right recurrent laryngeal nerve in cN0 papillary thyroid carcinoma

BACKGROUND

The lymph nodes in the right central compartment can be divided into 2 parts by the right recurrent laryngeal nerve (RLN), and there is a lack of an accurate and convenient method for assessing metastases in the lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) in cN0 thyroid papillary carcinoma patients.

METHODS

Patients diagnosed with cN0 thyroid papillary carcinoma and underwent intraoperative carbon nanoparticle-guided lymph node biopsy from January 2017 to November 2020 at the Center for Thyroid and Breast Surgery of Xuanwu Hospital were retrospectively analyzed. The intraoperative frozen section examination and postoperative LN-prRLN status should have been comprehensively recorded. The participants were divided into the LN-prRLN positive group and LN-prRLN negative group according to their recorded LN-prRLN status.

RESULTS

In total, 189 cases (LN-prRLN positive group, n=30; LN-prRLN negative group, n=159) were included in the analysis. The univariate and multivariate regression analyses revealed that the number of metastatic lymph nodes during intraoperative lymph node biopsy was the potential predictor for LN-prRLN metastasis [odds ratio (OR): 1.320, 95% confidence interval (CI): 1.057 to 1.649, P=0.014]. The receiver operating characteristic (ROC) curve showed that the area under the curve (AUC) reached 0.7 upon a combined analysis of multiple lymph node statuses located at pre-laryngeal (Delphian), pre-tracheal, and para-tracheal lymph nodes ipsilateral to the tumor in predicting the metastasis of LN-prRLN, and the cut-off value was 0.5.

CONCLUSIONS

Number of metastatic lymph nodes in intraoperative biopsy was an indicator of LN-prRLN metastasis in cN0 thyroid carcinoma patients. Patients staging in cN0 with negative intraoperative lymph node status might be considered not to require LN-prRLN dissection during central lymph nodes dissection.

Endoscopic Left Central Lymph Node Dissection of Thyroid Cancer: Safe, Feasible, and Relatively Easy

Purpose. The purpose of this study was to explore the feasibility of left central lymph node dissection (CLND) in endoscopic thyroidectomy via chest-breast approach (ETCB). Methods. Retrospective analysis of 57 cases of left CLND (group A) via ETCB, 35 cases of open left CLND (group B), and 90 cases of right CLND via ETCB (Group C) were performed from October 2014 to October 2019. Surgical data, complications, and follow-up data were compared among group A and group B, group A and group C, respectively. Results. There were no significant differences between group A and group B in intraoperative blood loss, tumor size, lymph node (LN) metastasis rate, dissected LN number, metastatic LN number, serum thyroglobulin (sTg), radioactive iodine uptake (RAIU), radioactive technetium uptake (RATU), radionuclide imaging of the residual area (RITRA), and radionuclide imaging of suspicious lymph node metastasis (RISLNM). There were no significant differences between group A and group C in age, operation time, intraoperative blood loss, postoperative hospital stay, tumor size, LN metastasis rate, dissected LN number, metastatic LN number, hypoparathyroidism, sTg, RAIU, RATU, RITRA, and RISLNM. There were 5 cases of temporary recurrent laryngeal nerve (RLN) palsy and 1 case of recurrence in group C. Besides, 1 case of lymphatic leakage was in group A. Conclusion. For selected cases, endoscopic left CLND is safe, feasible, efficient, and more easier than endoscopic right CLND.

A Novel Scoring System for Predicting the Metastases of Posterior Right Recurrent Laryngeal Nerve Lymph Node Involvement in Patients With Papillary Thyroid Carcinoma by Preoperative Ultrasound

OBJECTIVE

Our goal was to investigate the correlation between papillary thyroid carcinoma (PTC) characteristics on ultrasonography and metastases of lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN). There is still no good method for clinicians to judge whether a patient needs LN-prRLN resection before surgery, and we also wanted to establish a new scoring system to determine whether patients with papillary thyroid carcinoma require LN-prRLN resection before surgery.

PATIENTS AND METHODS

There were 482 patients with right or bilateral PTC who underwent thyroid gland resection from December 2015 to December 2017 recruited as study subjects. The relationship between the PTC characteristics on ultrasonography and the metastases of LN-prRLN was analyzed by univariate and logistic regression analyses. Based on the risk factors identified in univariate and logistic regression analysis, a nomogram-based LN-prRLN prediction model was established.

RESULT

LN-prRLN were removed from all patients, of which 79 had LN-prRLN metastasis, with a metastasis rate of 16.39%. Multivariate logistic regression analysis revealed that LN-prRLN metastasis was closely related to sex, age, blood supply, larger tumors (> 1 cm) and capsular invasion. A risk prediction model has been established and fully verified. The calibration curve used to evaluate the nomogram shows that the consistency index was 0.75 ± 0.065.

CONCLUSION

Preoperative clinical data, such as sex, age, abundant blood supply, larger tumor (> 1 cm) and capsular invasion, are positively correlated with LN-prRLN metastasis. Our scoring system can help surgeons non-invasively determine which patients should undergo LN-prRLN resection before surgery. We recommend that LN-prRLN resection should be performed when the score is above 103.1.

Metastasis of cN0 Papillary Thyroid Carcinoma of the Isthmus to the Lymph Node Posterior to the Right Recurrent Laryngeal Nerve

OBJECTIVE

The association between metastasis to the lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) and cN0 papillary thyroid carcinoma (PTC) located in the thyroid isthmus remains unknown; therefore, our goal was to analyze the characteristics of LN-prRLN metastasis of cN0 PTCs of the thyroid isthmus and determine its potential predictors.

PATIENTS AND METHODS

This retrospective study included patients who underwent bilateral central neck dissection between January 2018 and January 2021. The specimen was divided into five groups of prelaryngeal lymph node (LN), pretracheal LN, left paratracheal LN, lymph node anterior to the right recurrent laryngeal nerve (LN-arRLN), and LN-prRLN. Univariate and multivariate analyses were used to assess the association between the clinical pathologic variables and LN-prRLN metastases. Surgical complications were presented descriptively.

RESULTS

A total of 357 patients were included, LN-prRLN metastasis occurred in 23 (6.4%) patients, and LN-prRLN was positive only when there were other LN metastases, especially LN-arRLN metastases. Other independent risk factors for LN-prRLN included foci numbers ≥2, tumor size ≥5.0 mm, and extrathyroidal extensions. The rates of permanent hypoparathyroidism and vocal cord paralysis were 1.1% and 2.0%, respectively.

CONCLUSION

LN-prRLN metastases should not be ignored in cN0 PTC located in the thyroid isthmus; however, its dissection is a safe procedure, and the status of LN-arRLN can be a reliable predictor for LN-prRLN metastases.

Clinical and sonographic features for the preoperative prediction of lymph nodes posterior to the right recurrent laryngeal nerve metastasis in patients with papillary thyroid carcinoma

OBJECTIVE

To evaluate clinical and sonographic features predictive of lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) metastasis in patients diagnosed with papillary thyroid carcinoma (PTC).

METHODS

We retrospectively reviewed the clinical records and ultrasound (US) images of 479 consecutive PTC patients who received total thyroidectomy or right lobectomy with central neck dissection (CND) between October 2017 and October 2019. Univariate and multivariate analyses were performed to identify clinical and sonographic features associated with LN-prRLN metastasis. Receiver operating characteristic (ROC) analysis was applied to evaluate the efficacy of clinical and sonographic features in the preoperative prediction of LN-prRLN metastasis.

RESULTS

Overall, 127 (26.5%) patients had LN-prRLN metastasis. Multivariate logistic regression analysis showed that age < 45 years (p = 0.005; OR 2.155; 95% CI 1.262-3.683), male sex (p = 0.043; OR 1.657; 95% CI 1.016-2.704), tumor diameter > 1 cm (p = 0.042; OR 1.702; 95% CI 1.019-2.842), microcalcifications (p = 0.022; OR 1.980; 95% CI 1.104-3.551), and US-detected lateral compartment lymph node (LLN) metastasis (p = 0.001; OR 2.578; 95% CI 1.500-4.430) were independent risk factors for LN-prRLN metastasis. ROC analysis revealed that the multivariate logistic regression model had good accuracy in predicting LN-prRLN metastasis, with an area under the ROC curve of 0.758.

CONCLUSIONS

Age less than 45 years, male sex, tumor diameter larger than 1 cm, microcalcifications, and US-detected LLN metastasis may preoperatively predict LN-prRLN metastasis.

A Comparison of Two Operation Methods Revealed the Risk Factors and the Necessity of LN-prRLN Dissection in Papillary Thyroid Carcinoma: A Retrospective Cohort Study in FUSCC

BACKGROUND

Although the American Thyroid Association (ATA) guidelines indicate that central lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) should be routinely dissected, pr-RLN dissection is often neglected due to the high risk of injury to the recurrent laryngeal nerve (RLN). The purpose of this study was to investigate the risk factors associated with LN-prRLN metastasis in patients with papillary thyroid carcinoma (PTC) by preoperative examination and the indications for LN-prRLN dissection.

METHODS

A total of 1487 consecutive patients with PTC who underwent total thyroidectomy or right lobectomy plus isthmic resection with central LN dissection (CLND) were divided into two groups: patients with LN-prRLN dissection (group A) and patients without LN-prRLN dissection (group B). Clinicopathologic data were reviewed of the patients who were operated on by the same thyroid surgery team in the Department of Head Neck Surgery, Fudan University Shanghai Cancer Center (FUSCC) between August 2011 and May 2019. The relationships of LN-prRLN metastasis with clinicopathologic characteristics were analyzed by univariate and multivariate logistic regression.

RESULTS

The incidence of LN-prRLN metastasis was 34.1% (129/378). Univariate analysis showed that sex (P ≤ 0.001), tumor size (P ≤ 0.001), extrathyroidal extension (P=0.002), concurrent Hashimoto's thyroiditis (P=0.009), cLNMa (central lymph nodes anterior to the right recurrent laryngeal nerve) (P ≤ 0.001), cLNMa number (P ≤ 0.001), and lateral LN metastasis (LLNM) (P ≤ 0.001) were significantly associated with LN-prRLN metastasis in PTC. Multivariate logistic regression analysis revealed that tumor size (P=0.039), cLNMa (P=0.001), and LLNM (P=0.025) were independent risk factors for LN-prRLN metastasis in patients with PTC. Although there was no significant difference between the two groups in recurrence, we found that 4 cases relapsed in the LN-prRLN compartment in group B, while none relapsed in group A.

CONCLUSION

LN-prRLN metastasis is often identified in patients with PTC. Patients with large tumor sizes, cLNMa and LLNM are at a high risk of LN-prRLN metastasis and should be recommended for careful LN-prRLN dissection.

Risk factors of metastasis to the lymph nodes posterior to the right recurrent laryngeal nerve in papillary thyroid carcinoma

PURPOSE

To investigate the risk factors of lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) metastasis in papillary thyroid carcinoma.

METHODS

Clinicopathologic feature data of 427 patients with right or double lobes who underwent surgery between January 2014 to August 2019 in the Department of General Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, were retrospectively analyzed. The risk factors of LN-prRLN metastasis were analyzed by the Chi-squared test and multivariate logistic regression.

RESULTS

LN-prRLN metastasis was detected in 96 patients. Univariate analysis showed that age, right-side tumor diameter, capsular invasion, comorbid adenoma, and VIa compartment LN metastasis were significantly associated with LN-prRLN metastasis (all P < 0.05). Multivariate logistic regression analysis showed that right-side tumor diameter, capsular invasion, and VIa compartment LN metastasis were independent risk factors of LN-prRLN metastasis (all P ≤ 0.001). The receiver operating characteristic curve showed that the cutoff value of the right tumor diameter for predicting LN-prRLN metastasis was 1.25 cm (sensitivity = 0.5, specificity = 0.819, area under the curve = 0.720, P < 0.001).

CONCLUSION

The incidence of LN-prRLN metastasis cannot be ignored, and our findings indicate that prophylactic LN-prRLN dissection should be performed in patients with right-side tumor diameter ≥ 1.25 cm, capsular invasion, and VIa compartment LN metastasis.

Risk factors for right paraesophageal lymph node metastasis in papillary thyroid carcinoma: A meta-analysis

OBJECTIVE

Prophylactic dissection of the right paraesophageal lymph node (RPELN) in thyroid cancer is controversial. We performed a meta-analysis to provide evidence for RPELN dissection in thyroid cancer.

METHODS

We searched the PubMed and Science Citation Index Expanded (SCIE) databases for relevant studies published up to January 31, 2019. The patients involved all had a pathological diagnosis of papillary thyroid cancer (PTC) and had undergone total thyroidectomy or right lobectomy with central compartment lymph node dissection. The RPELNs had been kept aside during the operation.

RESULTS

Fourteen cohort studies involving 11,090 patients with PTC were included in the meta-analysis. There was RPELN metastases (RPELNM) in 1038 patients (9.36%). The factors related to RPELNM were: age <45 years, male sex, right lobe tumor, tumor >1 cm, extrathyroidal extension, capsular invasion, right paratracheal lymph node metastasis (RPTLNM), central lymph node metastasis (CLNM), lateral lymph node metastasis (LLNM), and tumor multifocality. There was no association between RPELNM and Hashimoto's thyroiditis (HT) and inferior pole tumors or tumor in the middle of the gland. With superior pole tumors, there was even less RPELNM.

CONCLUSIONS

The clinical features related to RPELNM are age <45 years, male sex, tumor >1 cm, tumor diameter >2 cm, right lobe tumor, RPTLNM, extrathyroidal extension, capsular invasion, CLNM, CLNM ≥3, LLNM and multifocality, which should be considered when evaluating RPELN dissection.

Clinicopathologic risk factors for right paraesophageal lymph node metastasis in patients with papillary thyroid carcinoma

OBJECTIVES

To investigate risk factors associated with right paraesophageal lymph node (RPELN) metastasis in patients with papillary thyroid carcinoma (PTC) and to determine the indications for right lymph node dissection.

METHODS

Clinicopathologic data from 829 patients (104 men and 725 women) with PTC, operated on by the same thyroid surgery team at the First Affiliated Hospital of Harbin Medical University from January 2013 to May 2017, were analyzed. Overall, 309 patients underwent total thyroidectomy with bilateral lymph node dissection, 488 underwent right thyroid lobe and isthmic resection with right central compartment lymph node dissection, and 32 underwent near-total thyroidectomy (ipsilateral thyroid lobectomy with contralateral near-total lobectomy) with bilateral lymph node dissection.

RESULTS

The overall rate of central compartment lymph node metastasis was 43.5% (361/829), with right central compartment lymph node and RPELN metastasis rates of 35.5% (294/829) and 19.1% (158/829), respectively. Tumor size, number, invasion, and location, lymph node metastasis, right central compartment lymph node metastasis, and right lateral compartment lymph node metastasis were associated with RPELN in the univariate analysis, whereas age and sex were not. Multivariate analysis identified tumors with a diameter ≥ 1 cm, multiple tumors, tumors located in the right lobe, right central compartment lymph node metastasis, and right lateral compartment lymph node metastasis as independent risk factors for RPELN metastasis.

CONCLUSIONS

Lymph node dissection, including RPELN dissection, should be performed for patients with PTC with a tumor diameter ≥ 1 cm, multiple tumors, right-lobe tumors, right central compartment lymph node metastasis, or suspected lateral compartment lymph node metastasis.

Predictors of lymph nodes posterior to the right recurrent laryngeal nerve metastasis in patients with papillary thyroid carcinoma: A retrospective study

The aim of this study was to identify the risk factors associated with lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) metastasis in patients with papillary thyroid carcinoma (PTC).A total of 81 PTC patients who underwent total/near-total thyroidectomy with LN-prRLN dissection in the Department of General Surgery at Guangdong General Hospital between June 2015 and August 2016 were assessed retrospectively. The relations of LN-prRLN metastasis with clinicopathologic characteristics of PTC were analyzed by univariate and multivariate logistic regression.The incidence of LN-prRLN metastasis in patients with PTC was 51.9% (42 of 81 cases). Univariate analysis showed that lateral LN metastasis (P = .005), VIa central LN metastasis (P = .000), pathologic tumor size (P = .000), capsular invasion (P = .002), and extrathyroidal invasion (P = .018) (P < .05) were significantly associated with the increased incidence of LN-prRLN metastasis in PTC. No significant correlations were found between LN-prRLN metastasis and other variables such as gender (P = .056), age (P = .448), clinical N stage (cN) (P = .063), tumor location (P = .336), tumor site (P = .909), right tumor existence (P = .793), and multifocality (P = .381). Multivariate logistic regression analysis revealed that VIa central LN metastasis (OR: 4.490, P = .027) was independent risk factors of LN-prRLN metastasis in patients with PTC.LN-prRLN metastasis is often indentified in patients with PTC. VIa central LN metastasis is an independent predictors of LN-prRLN metastasis, which allow for selective LN-prRLN dissection in patients with PTC.