Metastasis of Right Upper Para-Esophageal Lymph Nodes in Central Compartment Lymph Node Dissection of Papillary Thyroid Cancer

Risk Factors for Right Paratracheal Posterolateral Lymph Node Metastasis in Papillary Thyroid Cancer

Objectives

The incidence of papillary thyroid cancer (PTC) is increasing, and due to the favorable postoperative survival rates, the extent of surgery should be carefully determined, and complications during the operation should be avoided. The recurrent laryngeal nerve (RLN) divides the right paratracheal lymph node (RPTLN) into anteromedial and posterolateral compartments due to its anatomical course on the right and left sides of the neck, and the posterolateral lymph nodes are in close proximity to the RLN. Due to the risk of this complication, in this study, we aimed to determine the risk factors for the development of right paratracheal posterolateral lymph node (RPTPLLN) metastasis in PTC.

Methods

Between 2013 and 2022, patients who underwent central neck dissection (CLND) or central and lateral neck dissection due to the presence of PTC in the right lobe of the thyroid gland were included in the study. Descriptive data, along with preoperative imaging findings and postoperative pathology findings, were retrospectively evaluated.

Results

The data of 55 patients who met the criteria were statistically analyzed. Of these patients, 24 (43.6%) were male and 31 (56.4%) were female. The mean age was 47.9±17.5 years (range: 16-81). The mean tumor size was 2.17±1.43 cm (range: 0.4-7.0). RPTPLLN was observed in 13 patients (23.6%). Univariate analysis revealed that extrathyroidal extension (p=0.008), lymphovascular invasion (p=0.044), presence of right paratracheal anteromedial (RPTAMLN) metastasis (p=0.001), and presence of left paratracheal metastasis (p=0.049) were statistically significant factors. However, in the multivariate analysis, only the presence of RPTAMLN was determined to be a significant variable (p=0.035).

Conclusion

In patients undergoing surgery for PTC, the risk of metastasis in the RPTPLLN should be considered higher when there is metastasis in the RPTAMLN. We believe that formal dissection of the RPTLN should be considered for optimal evaluation in patients with tumors in the right lobe where central dissection is planned. Posterolateral dissection (PLD) should be routinely performed in the presence of clinical lymph nodes in the RPTAMLN. When a decision cannot be made, PLD may not be performed if the anteromedial tissue is examined with frozen pathology and the result is negative.

Preoperative Prediction of Metastatic Lymph Nodes Posterior to the Right Recurrent Laryngeal Nerve in cN0 Papillary Thyroid Carcinoma

Background

The advantages of the dissecting the metastatic lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) remain a great deal of controversies in papillary thyroid carcinoma (PTC) patients without clinical evidence. The purpose of our retrospective research was to investigate the predictive factors of the LN-prRLN in cN0 PTC patients.

Methods and Materials

Altogether 251 consecutive cN0 PTC participants accepted unilateral or bilateral thyroidectomy accompanied with LN-prRLN dissection between June 2020 and May 2023 were included in the research. Then, univariate and multivariate logical regression analysis were conducted to analyze the relationship between the LN-prRLN and these predictive factors, and a predictive model was also developed. Surgical complications of LN-prRLN dissection were also presented.

Results

The rate of LN-prRLN was 17.9% (45/251) in cN0 PTC patients after the analysis of postoperative histology. The age <55 years, multifocality, microcalcification, and BRAFV600E mutation were identified to be predictive factors of LN-prRLN in cN0 PTC patients. The risk score for LN-prRLN was calculated: risk score = 1.192 × (if age <55 years) + 0.808 × (if multifocality) + 1.196 × (if microcalcification in nodule) + 0.918 × (if BRAFV600E mutation in nodule). The rates of the transient hypoparathyroidism and hoarseness were 1.2% (3/251) and 2.0% (5/251), respectively.

Conclusion

The age <55 years, multifocality, microcalcification, and BRAFV600E mutation are independent predictors of the LN-prRLN in cN0 PTC patients. An effective predictive model was established for predicting the LN-prRLN in cN0 PTC patients, with the aim to better guide the surgical treatment of PTC. A thorough inspection of the lateral compartment is recommended in PTC patients with risk factors. The multicenter research with long-term follow-up should be carried out to ascertain the optimal surgical approach for patients with PTC.

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.

Analysis of risk factors for posterior laryngeal recurrent nerve metastasis in micropapillary thyroid carcinoma

Posterior recurrent laryngeal nerve (RLN) lymph node dissection remains controversial in the operation of thyroid cancer, especially in cases of papillary thyroid microcarcinoma (PTMC). The present study aimed to evaluate the risk factors for posterior RLN lymph node metastasis in patients with PTMC. Two hundred and thirty-nine patients pathologically diagnosed with PTMC after surgery between June 2016 and June 2017 were included. Risk factors including age, sex, tumor diameter, multiple tumor focus, membrane invasion and lateral cervical lymph node metastasis condition, were analyzed, and their corresponding OR values were calculated. The results indicated that posterior RLN lymph node metastasis was pathologically identified in 27/239 patients. Membrane invasion (p = 0.024), VIa lymph node metastasis (p < 0.01), and lateral cervical lymph node metastasis (p < 0.01) were considered to be risk factors for posterior RLN lymph node metastasis. It is concluded that membrane invasion, VIa lymph node metastasis, and lateral cervical lymph node metastasis significantly increased the incidence of posterior RLN lymph node metastasis. Complete dissection of the posterior RLN lymph node was essential for patients with these risk factors.

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.

A meta-analysis of risk factors for lymph node posterior to the right recurrent laryngeal nerve metastasis in papillary thyroid carcinoma

Background

Whether the lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) should be dissected is still controversial. This meta-analysis aimed to assess the risk factors for LN-prRLN metastasis in papillary thyroid carcinoma (PTC).

Methods

We retrieved relevant studies published before May 2020 from the Wanfang Data, CNKI, PubMed, Embase, Web of Science and Cochrane Library databases. Heterogeneity was assessed with the Q-test and inconsistency index and sensitivity analysis and subgroup analysis were then used to find the source of heterogeneity. Begg test and generate a funnel chart to assess publication bias.

Results

We retrieved 236 articles, 14 articles were selected as the subjects of our research. Fourteen studies involving 10,580 patients were analysed in this study. The LN-prRLN metastasis rate was 9.22% (975/10,580). The results of the meta-analysis showed that sex (P<0.001), age (P<0.001), tumour size (P<0.001), multifocality (P<0.001), capsular invasion (P=0.04), extrathyroidal extension (P<0.001), superficial central lymph node (VIa-LN) metastasis (P<0.001), and lateral lymph node (LLN) metastasis (P<0.001) were correlated with LN-prRLN metastasis.

Discussion

Male sex, age ≤45 years, tumour size >1 cm, multifocality, capsular invasion or extrathyroidal extension, and VIa-LN metastasis or LLN metastasis in PTC patients were significant risk factors for predicting LN-prRLN metastasis. B ultrasound and CT scans are expected to predict LN-prRLN metastasis in the future.

Registration

This research is registered on the PROSPERO website (registration number: CRD42020200898).

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.

A NOVEL SCORING SYSTEM FOR THE RISK OF PAPILLARY THYROID CANCER METASTASES IN LYMPH NODES POSTERIOR TO THE RIGHT OF THE RECURRENT LARYNGEAL NERVE

OBJECTIVE

Some surgeons believe that dissection posterior to the right recurrent laryngeal nerve lymph node (PRRLN-LN) is unnecessary for the low metastasis rate and high complication risk. However, persistent metastatic lymph nodes may have a higher recurrence rate, surgical risk, and complications. Thus, it is important to distinguish patients who require PRRLN-LN dissection. To identify the risk factors for lymph nodes posterior to the right recurrent laryngeal nerve metastasis (LN-prRLN) and establish a scoring system to help determine whether PRRLN-LN dissection is required in patients with papillary thyroid carcinoma.

METHODS

821 participants were randomly allocated to the development and validation cohorts in a 2:1 ratio. A nomogram-based predictive model for LN-prRLN was established based on the risk factors identified in the development cohort.

RESULTS

LN-prRLN was diagnosed pathologically in 124 of 821 patients (15.1%) from the entire cohort. Multivariate analysis identified age (odds ratio [OR], 0.964; 95% CI, 0.945-0.983; P < .001), tumor size (OR, 1.536; 95% CI, 1.135-2.079; P = .005), extrathyroidal extension (OR 2.271, 95% CI, 1.368-3.770; P = .002), clinically involved right central compartment lymph node metastasis (OR 1.643, 95% CI, 1.055-2.559; P = .028), and right lateral lymph node metastasis (OR 4.271, 95% CI, 2.325-7.844; P < .001) as the predictors of LN-prRLN. A risk model was established and well validated. Calibration curves to evaluate the nomogram in both the development and validation cohorts revealed a concordance index of 0.756 ± 0.058 and 0.745 ± 0.042, respectively.

CONCLUSION

Our scoring system may be useful for helping the surgeons decide which patients should undergo the dissection of PRRLN-LN.

Prophylactic lymph node dissection in clinically N0 differentiated thyroid carcinoma: example of personalized treatment

Considering the 'differentiated thyroid carcinoma (DTC) epidemic', the indolent nature of DTC imposes a treatment paradigm shift toward elimination of recurrence. Lymph node metastases in cervical compartments, encountered in 20-90% of DTC, are the main culprit of recurrent disease, affecting 5-30% of patients. Personalized risk-stratified cervical prophylactic lymph node dissection (PLND) at initial thyroidectomy in DTC with no clinical, sonographic or intraoperative evidence of lymph node metastases (clinically N0) has been advocated, though not unanimously. The present review dissects the controversy over PLND. Weighing the benefit yielded from PLND up against the PLND-related morbidity is so far hampered by the inconsistent profit yielded by PLND and the challenging patient selection. Advances in tailoring PLND are anticipated to empower optimal patient care.

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.

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.

Risk Factors for Predicting Lymph Nodes Posterior to Right Recurrent Laryngeal Nerve (LN-prRLN) Metastasis in Thyroid Papillary Carcinoma: A Meta-Analysis

OBJECTIVE

To evaluate the risk factors for predicting lymph nodes (LN) posterior to right recurrent laryngeal nerve metastasis in thyroid papillary carcinoma.

METHODS

PubMed, PMC, EMBASE, and the Cochrane Library were systematically searched for articles published spanning 30/06/2009-30/8/2018 using multiple search terms. Thirteen articles involving 10,014 patients were reviewed in our meta-analysis. Stata 15.1 software was used for the meta-analysis.

RESULTS

The rate of LN posterior to right recurrent laryngeal nerve (LN-prRLN) metastasis was 8.65%. Univariate analysis showed that age (P = 0.001), gender (P < 0.001), tumour size (P < 0.001), lateral LN metastasis (P < 0.001), extrathyroidal invasion (P < 0.001), multifocality (P = 0.005), capsule invasion (P < 0.001), tumour location (P = 0.076), lymph nodes anterior to right recurrent laryngeal nerve (LN-arRLN) metastasis (P < 0.001), and central LN metastasis (P < 0.001) were significantly associated with the increased incidence of LN-prRLN metastasis in thyroid papillary carcinoma.

CONCLUSION

PTC patients aged <45, male, and with tumours > 1 cm, lateral LN metastasis, extrathyroidal invasion, multifocality, capsule invasion, LN-arRLN metastasis, or central LN metastasis were significantly correlated with lymph nodes posterior to right recurrent laryngeal nerve metastasis, indicating LN-prRLN 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.

Model of lymph node metastasis posterior to the right recurrent laryngeal nerve in papillary thyroid carcinoma

Background

Cervical lymph node metastasis (LNM) is a prognostic factor of papillary thyroid carcinoma (PTC). The way to deal with lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) is controversial. Nevertheless, if metastatic lymph nodes are not removed during the first operation, the subsequent salvage surgery of recurrent tumor in this area would entail high risk and complication. The purpose of this study was to develop a preoperative prediction model for LN-prRLN metastasis in PTC patients using clinicopathological characteristics.

Patients and methods

We performed a prospective study of 595 patients with PTC who underwent LN-prRLN dissection from March 2014 to June 2017. The clinicopathological data were randomly divided into derivation (n=476) and validation sets (n=119). A predictive model was initially established based upon the data of the derivation set via multivariate analyses, and the accuracy of the model was then examined with data of the validation set. The discriminative power of this model was assessed in both sets.

Results

Metastases of the LN-prRLN were identified in 102 (17.14%) of 595 patients. Age (odds ratio [OR] 0.971, 95% CI, 0.949–0.994, p=0.013), tumor size (OR 2.163, 95% CI, 1.431–3.270, p<0.001), capsular invasion (OR 1.934, 95% CI, 1.062–3.522, p=0.031), and right LNM (OR 3.786, 95% CI, 2.012–7.123, p<0.001) were significantly associated with LN-prRLN metastasis. The areas under the curves were 0.790 for the derivation set (sensitivity 71.95%, specificity 78.68%) and 0.878 for the validation set (sensitivity 85.00%, specificity 78.79%).

Conclusion

We developed and validated the first model to predict LN-prRLN metastases in patients with PTC based on clinicopathological parameters.

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.

Clinical value and indication for the dissection of lymph nodes posterior to the right recurrent laryngeal nerve in papillary thyroid carcinoma

Lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) are common sites of nodal recurrence after the resection of papillary thyroid carcinoma (PTC). However, the indication for LN-prRLN dissection remains debatable. We therefore studied the relationships between LN-prRLN metastasis and the clinicopathological characteristics in 306 patients with right or bilateral PTC who underwent LN-prRLN dissection. We found that LN-prRLN metastasis occurred in 16.67% of PTC and was associated with a number of the clinicopathological features. The receiver-operator characteristic (ROC) analysis showed that the areas under the ROC curves for the prediction of LN-prRLN metastasis by the risk factors age < 35.5 years, right tumor size > 0.85 cm, lymph node (right cervical central VI-1) number > 1.5, metastatic lymph node (right cervical central VI-1) size > 0.45 cm, and lymph node number in the right cervical lateral compartment > 0.5 were 0.601, 0.815, 0.813, 0.725, and 0.743, respectively.

In conclusion, the risk factors for LN-prRLN metastasis in patients suffering right thyroid lobe or bilateral PTC include age ≤ 35.5 years, right tumor size ≥ 0.85 cm, capsular invasion, metastatic lymph node (right cervical central VI-1) number ≥ 2, metastatic lymph node (right cervical central VI-1) size ≥ 0.45 cm, and metastatic lymph node number in the right cervical lateral compartment ≥ 1. In patients whose risk factors can be identified pre-operatively or intraoperatively, the dissection of LN-pr-RLN should be considered during right cervical central compartment dissection.

Predictive factors of right paraesophageal lymph node metastasis in papillary thyroid carcinoma: Single center experience and meta-analysis

BACKGROUND

We performed this retrospective study to identify predictors of right paraesophageal lymph node metastasis, and reviewed previous studies related to this topic.

METHODS

Between June 2005 and March 2015, 1107 patients were diagnosed with papillary thyroid carcinoma and underwent surgery at Pusan National University Hospital.

RESULTS

Right paraesophageal lymph node metastasis was observed in 171 (15.4%) patients. Multivariate analyses showed that the risk of right paraesophageal metastasis was significantly associated with tumor size, location, a higher number of metastatic central lymph nodes, and lateral lymph node metastasis. In a meta-analysis of the eligible studies, tumor size, number of metastatic central lymph nodes, and lateral lymph node metastasis showed significant relationships with the risk of right paraesophageal metastasis.

CONCLUSIONS

In patients with risk factors such as those identified in our study, the possibility of right paraesophageal metastasis should be kept in mind, and careful inspection and dissection are required.

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

OBJECTIVES

To study the clinicopathological characteristics and the risk factors of lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) metastasis in differentiated thyroid carcinoma; and to identify the indication for LN-prRLN dissection.

METHODS

We treated 145 patients with differentiated thyroid carcinoma with appropriate surgical intervention. The specimens were examined by the pathologists. The right paratracheal lymph nodes were divided into two groups: anterior or posterior to right recurrent laryngeal nerve (VIa or VIp compartment, respectively). We recorded the clinical characteristics, histopathological features of the primary tumors, and lymph node metastasis of the patients. The results were statistically analyzed.

RESULTS

There were 85 patients (58.6%) with central lymph node metastasis, of whom 61 (42.1%) had metastasis in VIa compartment; 16 patients (11.0%) had VIp subdistrict metastasis; and 25 patients had lateral lymph node metastasis. Multiplicity, larger tumor (≥1 cm), and coexistence of central lymph node metastasis, VIa compartment metastasis, and lateral lymph node metastasis were all significantly related with LN-prRLN metastasis, while sex, age, location of the tumor, and extrathyroid extension of the tumor showed no significant relation (p > 0.05).

CONCLUSION

The incidence of LN-prRLN metastasis was lower than other central lymph nodes, as well as lymph nodes anterior to right recurrent laryngeal nerve. When there were multiple foci of tumors, or the tumor was larger than 1 cm, or central or lateral LN metastasis was indicated by preoperative ultrasound or confirmed by intraoperative frozen sections, it is strongly recommended that exploration and dissection of the LN-prRLN should only be performed by experienced surgeons.

Risk factors and indication for dissection of right paraesophageal lymph node metastasis in papillary thyroid carcinoma

BACKGROUND

Right paraesophageal lymph nodes (RPELNs) are located behind right recurrent laryngeal nerve which often ignored in central compartment lymph nodes (LNs) dissection of papillary thyroid carcinoma (PTC) patients. The aim of this study was to identify the risk factors for RPELN metastasis and indications for RPELN dissection.

METHODS

Medical record of 246 consecutive PTC patients (194 female, 52 male), who underwent total thyroidectomy (244 patients) or right lobectomy (2 patients) with central compartment LN dissection (13 ipsilateral and 233 bilateral), were reviewed. The RPELNs were kept separately during the operation. The clinical pathology data was collected and analyzed.

RESULTS

RPELN metastasis was confirmed in 33 patients (13.4%) and were discovered in 18.5% (31/168) of right lesion, 34.4% (31/90) of right central group LN (rCLN) metastasis, 33.3% (18/54) of lateral compartment LN (LLN) metastasis, 25.7% (9/35) of local recurrent patients respectively. The ultrasound suspected metastatic LNs, tumor diameter, tumor number, tumor location, and numbers of metastatic Delphian LNs, central group LNs (CLNs), rCLNs, and LLNs between patients with and without RPELN metastasis showed significant differences in univariate analysis (P < 0.05). In multivariate analysis, number of metastatic rCLNs (1-2: OR 13.6, 95% CI, 2.7-67.5; ≧3: OR39.4, 95% CI, 7.7-200.9), right side tumor (OR 6.4, 95% CI, 1.1-35.6), and three or more metastatic LLNs (OR 3.5, 95% CI, 1.2-10.2) were independent risk factors for RPELN metastasis.

CONCLUSIONS

PTC patients with right lobe lesions, especially with potential rCLN metastasis, are at considerable risk of RPELN metastasis. RPELN dissection should be considered in these patients.

Central neck dissection in the treatment of well-differentiated thyroid cancer

Therapeutic central compartment neck dissection (CCND) is required for confirmed nodal metastasis in patients with differentiated thyroid cancer. The need for routine prophylactic CCND in patients with papillary thyroid cancer is controversial. This article presents the current evidence to inform the debate against the background of the recommendations of US and British thyroid cancer guidelines. Potential advantages of pCCND include reduced local recurrence, preventing the need for further central compartment surgery and improved staging. Opponents claim that there is no proven patient benefit and that there is increased risk of recurrent laryngeal nerve injury and hypocalcemia.

Metastatic lymph node status in the central compartment of papillary thyroid carcinoma: A prognostic factor of locoregional recurrence

BACKGROUND

The purpose of this study was to present our focus on the lymph node status in the central compartment and evaluate the relevant factors and disease recurrence.

METHODS

Between January 2004 and December 2009, 1040 patients were diagnosed with papillary thyroid carcinoma (PTC) and underwent surgery.

RESULTS

The number of metastatic lymph nodes was a significant predictor for recurrence conferring a hazard ratio of 1.36 (confidence interval = 1.103-1.680; p = .004). The receiver operating characteristic (ROC) curve was calculated to determine the cutoff number of lymph nodes that predicted recurrence with the highest sensitivity and specificity (area under the ROC curve, 0.794; SE, 0.077; p = .001). The sensitivity/specificity of >3 metastatic lymph nodes for predicting recurrence was 63.6%/77.0%, respectively.

CONCLUSION

The number of metastatic lymph nodes in the central compartment was a statistical significant predictive factor associated with disease recurrence. Further study is required to confirm the relationship between the number of lymph nodes and disease recurrence. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1172-E1176, 2016.

Ultrasonographic findings relating to lymph node metastasis in single micropapillary thyroid cancer

Background

In thyroid cancer, preoperative ultrasonography (US) is performed to detect the primary tumor and lymph node metastasis (LNM), which are related to prognosis. This study examined the relationships between specific US findings and LNM in micropapillary thyroid cancer (MPTC).

Methods

Data on 220 patients with solitary MPTC who underwent total thyroidectomy and neck dissection between 2008 and 2009 were evaluated retrospectively. We classified the US findings according to the nature, shape, echogenicity, extent, margin, and calcification of the primary tumor and evaluated the correlations between these findings and those of LNM.

Results

Hypoechogenicity (odds ratio = 2.331, P = 0.025) and marked hypoechogenicity (OR = 4.032, P = 0.016) of MPTC were risk factors for central LNM. All of the patients with lateral cervical LNM showed hypoechogenicity or marked hypoechogenicity. Hypoechogenicity (odds ratio = 5.349, P = 0.047) and other types of calcification (odds ratio = 2.495, P = 0.010) were significant risk factors for lateral cervical LNM.

Conclusions

Specific sonographic findings (hypoechogenicity or marked hypoechogenicity, and calcification) suggest LNM.

Risk factors and clinical indication of metastasis to lymph nodes posterior to right recurrent laryngeal nerve in papillary thyroid carcinoma: a single-center study in China

BACKGROUND

Lymph nodes posterior to right recurrent laryngeal nerve (PRRLN) may be frequently overlooked during central compartment dissection (CCD) for papillary thyroid carcinoma (PTC). The purpose of this study was to investigate risk factors of lymph node PRRLN metastasis in right-sided PTC, thereby to identify the indications for lymph node PRRLN dissection.

METHODS

We conducted a retrospective study of patients with right-sided PTC who underwent a thyroidectomy plus lymph node PRRLN dissection during ipsilateral CCD.

RESULTS

Overall, 108 patients (26.7%) had lymph node PRRLN metastases, including 26 (6.4%) who presented with solely lymph node PRRLN positivity. Factors of extrathyroidal extension, multifocality, larger tumor (≥1 cm), level VIa positivity (p < .0001 for each), and lateral compartments positivity (p = .0002) significantly predicted lymph node PRRLN metastasis in right-sided PTC.

CONCLUSION

Lymph node PRRLN should be routinely explored during CCD because of the possibility of only involvement in PTC. Factors of tumors larger than 1 cm, multifocality, and extrathyroidal extension were independent predictors of lymph node PRRLN metastasis in right-sided PTC, and suggested the clinical indications of lymph node PRRLN dissection.

Surgical management of the lateral neck compartment for metastatic thyroid cancer

PURPOSE OF REVIEW

The lateral neck compartment is the second most frequent target region for metastatic papillary thyroid cancer (PTC) and medullary thyroid cancer (MTC). Lateral lymph node metastases are associated with locoregional recurrence and, when they involve either side of the neck, with mediastinal and distant metastases.

RECENT FINDINGS

For tumors originating from the upper thyroid pole, the first nodal basin is not invariably the central compartment (as for primaries arising from the inferior thyroid pole) but often the upper part of the ipsilateral lateral compartment. Lymph node dissection of the first basin may differ depending on the location of the primary tumor. Involvement of the contralateral lateral compartment is seen in PTC with extensive central compartment involvement, and in MTC with preoperative basal calcitonin levels more than 200  pg/ml (normal limit <10  pg/ml).

SUMMARY

After lateral lymph node dissection for metastatic thyroid cancer, dysfunction of lateral neck nerves is fairly common. This observation underpins the importance of striking a balance between oncological benefit and surgical risk. Lateral lymph node dissection may be warranted for an upper thyroid pole primary, for a tumor with extensive involvement of the central compartment, and for an MTC with increased basal calcitonin level of 20-200  pg/ml (ipsilateral dissection) or more than 200  pg/ml (bilateral dissection).

Incidence and predictors of right paraesophageal lymph node metastasis of N0 papillary thyroid carcinoma located in the right lobe

Papillary thyroid carcinoma (PTC) frequently metastasizes to the regional lymph nodes and, thus, guidelines edited by Japan Association of Endocrine Surgeons/Japanese Society of Thyroid Surgery routinely recommend central node dissection even for patients with no clinically detectable node metastasis (N0). However, in the central compartment, metastasis to the right paraesophageal node has not been intensively investigated. We investigated the incidence and predictors of right paraesophageal node metastasis based on pre- and intraoperative findings in 922 patients with N0 PTC in the right lobe. Fourteen percent of patients were microscopically positive for right paraesophageal node metastasis, and the incidence was smaller than that for pre- and right paratracheal node metastasis (46%). On multivariate analysis, a tumor size ≥ 2 cm and significant extrathyroid extension were independent predictors of metastasis. Microscopically pre- and right paratracheal node-positive PTC more often (p < 0.0001) metastasized to the right paraesophageal node. Taken together, in N0 PTC in the right lobe, right paraesophageal node dissection should be considered in tumors 2 cm or larger and/or with significant extrathyroid extension, or when pre- and right paratracheal node metastasis is suspected based on the intraoperative findings.

Right paraesophageal lymph node dissection in papillary thyroid carcinoma

BACKGROUND

This study was designed to identify the patients with papillary thyroid carcinoma (PTC) who would benefit from RPELN dissection.

SUMMARY BACKGROUND DATA

The value of the right paraesophageal lymph nodes (RPELNs), which are located posterior to the right recurrent laryngeal nerve, may be underestimated. Although the RPELNs are common sites of nodal recurrence, few related studies have been reported.

METHODS

We retrospectively reviewed the medical records of 369 patients (286 female, 83 male) who underwent total thyroidectomy (327 patients) or right lobectomy (42 patients) with therapeutic or prophylactic central lymph node dissection for primary PTC between August 2008 and January 2010 at the Department of Surgery, Samsung Medical Center.

RESULTS

Central lymph node (CLN) metastases were present in 51.2% (189 of 369) of the patients, and RPELN metastases were present in 12.2% (45 of 369) of the patients. The rate of RPELN metastasis was 19.6% (37 of 189) in patients with CLN metastases, but only 4.4% (8 of 180) in patients with no CLN metastases (P < .001). A univariate analysis revealed that RPELN metastasis was significantly correlated with the size of the tumor, the perithyroidal extent (capsular invasion), CLN metastasis, and lateral lymph node metastases. There were no significant differences in terms of gender, mean age, or number of tumors between groups. A multivariate analysis revealed that tumor size (>1 cm) and number of CLN metastases (≥ 3) were significantly correlated with RPELN metastasis.

CONCLUSIONS

RPELN dissection should be considered in patients with right thyroid cancer, tumors larger than 1 cm, or multiple CLN metastases.