Contralateral Paratracheal Lymph Node Research Articles

Comparative Study between Total Thyroidectomy with Ipsilateral versus Bilateral Prophylactic Central Neck Dissection in Patients with Clinically Node – Negative Papillary Thyroid Carcinoma. A Meta-Analysis

Abstract Background Papillary thyroid carcinoma (PTC) accounts for > 80% of all thyroid malignancies. It is generally slow-growing and the overall prognosis is excellent, with 5-year, 10-year, and 20-year survival rates of 94%, 89%, and 87%, respectively. Aim of the Work The aim of this study is to compare between unilateral PCND and bilateral PCND in patients with clinically unifocal cN0 PTC using meta-analysis approach Methodology A Systemic review and meta-analysis Study was performed after the data extraction process. Five studies comparing the out-comes of unilateral PCND and bilateral PCND procedures in adult patients with PTC CN0 were included in this study. The publicly available literature on PubMed, and, the Web of Knowledge, and the China Journal Net, EMBASE, Cochrane Library, and Scopus databases and the ClinicalTrials.gov registry. Published from January 2005 to December 2020 concerning TT plus ipsilateral PCND versus TT plus bilateral PCND for PTC CN0 will be retrieved by searching the national and international online databases. Results The result of our study revealed that: Bilateral central neck dissection had higher insignificant operative time than ipsilateral one, bilateral central neck dissection had higher overall significant complications rate than ipsilateral one, bilateral central neck dissection had higher significant permanent hypo PTH and insignificant hematoma, seroma, and transient hypo PTH rate than ipsilateral one, ipsilateral central neck dissection had higher insignificant PRLNP, TRLNP rate nearly equal with bilateral one, ipsilateral CND appears to be sufficient in patients with tumors<1 cm as bilateral central neck dissection had higher insignificant tumor size than ipsilateral one, there was no statistically significant difference found between unilateral PCND and bilateral PCND regarding rate of recurrence. Conclusion We suggest that, ipsilateral central neck dissection may be a reasonable surgical option for prophylactic CND in unilateral PTC with clinically negative lymph nodes because of its lower rates of contralateral paratracheal node metastasis and transient hypoparathyroidism and lower complications than bilateral pCND. and effective for selected patients undergoing a total thyroidecto- my for cN0 unilateral PTC.

Prelaryngeal and/or pretracheal lymph node metastasis could help to identify papillary thyroid carcinoma with intermediate risk from unilateral lobe cT1-2N0 papillary thyroid carcinoma.

The study aims to explore the possibility of prelaryngeal and/or pretracheal lymph node metastasis in identifying papillary thyroid carcinoma with more than 5 metastatic central lymph nodes from unilateral lobe cT1-2N0 papillary thyroid carcinoma. A retrospective analysis was conducted on patients who underwent the initial thyroid surgery for unilateral lobe cT1-2N0 PTC in a single tertiary center between July 2018 to December 2022. Multivariable binary logistic regression analysis was used to identify risk factors for unilateral lobe cT1-2N0 papillary thyroid carcinoma with more than 5 metastatic central lymph nodes. A total of 737 patients were included in the study and 399 patients were confirmed to suffer from occult central lymph node metastasis. The larger size of the largest diameter of tumor (> 1cm; OR = 3.3, 95%CI 1.6 - 6.83; p = 0.001), pretracheal lymph node metastasis (OR = 5.91, 95%CI 2.73 - 12.77; p < 0.001), prelaryngeal lymph node metastasis (OR = 3.74, 95%CI 1.73 - 8.1; p = 0.001), ipsilateral paratracheal lymph node metastasis (OR = 12.22, 95%CI 3.43 - 43.48; p < 0.001), and contralateral paratracheal lymph node metastasis (OR = 7.68, 95%CI 3.86 - 15.3; p < 0.001) were confirmed to be risk factors for unilateral lobe cT1-2N0 PTC with more than 5 metastatic central lymph nodes. When more than two metastatic prelaryngeal and/or pretracheal lymph nodes occurred, the incidence of more than 5 metastatic central lymph nodes was 71.2%. Prelaryngeal and/or pretracheal lymph node metastasis could help to identify papillary thyroid carcinoma with more than 5 metastatic central lymph nodes from unilateral lobe cT1-2N0 papillary thyroid carcinoma. When more than two metastatic pretracheal and/or prelaryngeal lymph nodes occurred, total thyroidectomy and ipsilateral central lymph node dissection should be performed and contralateral paratracheal lymph node dissection might be also necessary.

Relationship between pretracheal and/or prelaryngeal lymph node metastasis and paratracheal and lateral lymph node metastasis of papillary thyroid carcinoma: A meta-analysis

ObjectiveWe conducted a meta-analysis to study the relationship between pretracheal and/or prelaryngeal lymph node metastasis and paratracheal and lateral lymph node metastasis in papillary thyroid carcinoma.MethodA systematic literature search was conducted using PubMed, Embase, and the Cochrane Library electronic databases for studies published up to February 2022. The reference lists of retrieved articles were also reviewed. Two authors independently assessed the methodological quality and extracted the data. A random-effects model was used to calculate the overall pooled relative risk. Publication bias in these studies was evaluated using Egger’s test and Begg’s test.ResultsTwenty-five independent studies involving 10,525 patients were included in the meta-analysis. The pooled relative risk for ipsilateral and contralateral paratracheal lymph node metastasis was 3.01 (95% confidence interval [CI]: 1.66, 5.45) and 5.68 (95% CI: 2.50, 12.88), respectively, in patients with pretracheal lymph node metastasis. Among patients with prelaryngeal lymph node metastasis, the pooled relative risk for ipsilateral paratracheal and/or pretracheal contralateral paratracheal, and lateral lymph node metastasis was 2.02 (95% CI: 1.90, 2.14), 2.22 (95% CI: 1.34, 3.67), and 3.85 (95% CI: 2.89, 5.14), respectively.ConclusionPretracheal lymph node metastasis and prelaryngeal lymph node metastasis were significantly associated with an increased likelihood of both ipsilateral lymph node metastasis and contralateral paratracheal lymph node metastasis in papillary thyroid carcinoma. Prelaryngeal lymph node metastasis was positively correlated with the incidence of lateral lymph node metastasis.

Role and extent of neck dissection for neck lymph node metastases in differentiated thyroid cancers

Differentiated thyroid cancers (DTC) consist of 95% of thyroid tumors and include papillary thyroid cancer (PTC), follicular thyroid cancer (FTC), and Hurthle cell thyroid cancer (HTC). Rates of lymph node metastases are different depending on histologic subtypes and <5% in FTC and between 5% and 13% in HTC. Lymph node metastasis is more frequent in PTC and while rate of clinical metastasis can be seen approximately 30% rate of routine micrometastasis can be seen up to 80%.Lymph node metastasis of DTC mostly develops first in the Level VI lymph nodes at the central compartment starting from the ipsilateral paratracheal lymph nodes and then spreading to the contralateral paratracheal lymph nodes. Spread to the Level VII is mostly after Level VI invasion. Subsequent spread is to the lateral neck compartments of Levels IV, III, IIA, and VB and sometimes to the Levels IIB and VA. Occasionally skip metastasis to the lateral neck compartments develop without spreading to the central compartments and this situation is more frequent in upper pole tumors.Although application of prophylactic central neck dissection (pCND) in DTC increases the rate of complication, due to its unclear effects on oncologic results and quality of life, the interest to the pCND is decreasing and debate on its surgical extent is increasing. pCND is not essential in DTC and characteristics of patient and tumor and experience of surgeon should be considered when deciding for pCND. Due to lower complication rate of one sided pCND compared to bilateral central neck dissection (CND), low possibility of contralateral central neck metastasis and low risk of recurrence, application of one-sided CND is logical. Although therapeutic CND (tCND) is the standart treatment when there is a clinically involved lymph node, extent of dissection is a matter of debate. A case-based decision for the extent of tCND can be made by considering patient and tumor characteristics and experience of the surgeon.Due to the higher complication risk of bilateral CND, unilateral tCND can be performed if there is no suspicious lymph node on the contralateral side and bilateral tCND can be applied when there is a suspicion for metastasis only on the contralateral side or there are features for risk of metastasis to the contralateral side. In patients with clinical central metastasis owing to intra-operative pathology results by frozen section procedure are compatible with post-operative pathology results, when there is a suspicion for contralateral metastasis, a decision for one- or two-sided dissection can be made using frozen section procedure. In DTC, it can be stated that there is a consensus in the literature about not performing prophylactic lateral neck dissection (LND), but performing therapeutic LND (tLND). In addition, there is a debate on the extent of tLND.In a meta-analysis about lateral metastasis, the rates of metastasis to the Levels IIA, IIB, III, IV, VA, and VB were 53.1%, 15.5%, 70.5%, 66.3%, 7.9%, and 21.5%, respectively. Ultrasonography (USG) is an effective procedure for detection of cervical nodal metastasis on lateral compartment. Pre-operative imaging with USG and/or combination with the fine needle aspiration biopsy (cytology/molecular test/Thyroglobulin test) can allow pre-operative detection and verification of lateral lymph node metastasis.Extent of tLND can be determined to minimize morbidity considering pre-operative USG findings, pre-operative tumor and clinical features of lateral metastasis. Especially in the presence of limited lateral metastases, limited selective LND such as Levels III, IV or Levels IIA, III, IV can be applied according to the patient. Levels IIB and VB should be added to the dissection in the presence of metastases in these regions. In cases that increase the risk of Level IIB involvement, such as presence of metastasis at Level IIA, extranodal tumor involvement, presence of multifocal tumor, and in cases that increase the risk of Level VB involvement such as macroscopic extranodal spread, and simultaneous metastases at Levels II, III, IV; Levels IIB and VB can be added to dissection material. Levels I and VA should be added to the dissection in the presence of clinically detected metastases.

The Extent of Therapeutic Central Compartment Neck Dissection in Unilateral cT1N1a or cT2N1a Papillary Thyroid Carcinoma.

PurposePapillary thyroid carcinomas (PTCs) frequently metastasize to the central neck compartment. Therapeutic central compartment neck dissection (CCND) is a well-established treatment for PTC nodal metastases; however, the extent to which therapeutic CCND should be performed remains controversial. In this study, we investigated the predictive risk factors for contralateral paratracheal lymph node metastasis (LNM) in unilateral cT1N1a or cT2N1a PTC.Patients and MethodsIn this case–control study, which was conducted at a single center, demographic and pathological data from unilateral cT1N1a or cT2N1a PTC patients were collected from January 2017 to March 2019. All patients were treated with total thyroidectomy and bilateral CCND.ResultsTwo hundred thirty-seven patients met the inclusion criteria. Forty-nine patients (20.7%) were diagnosed with positive lymph nodes in the contralateral paratracheal region. Male sex (p=0.003), T2 disease (21–40 mm) (p<0.001), inferior pole tumor (p=0.011), near isthmus tumor (p<0.001), aggressive pathology (p<0.001), intraglandular dissemination (p=0.009), pretracheal LNM (p<0.001), >5 metastatic lymph nodes (p<0.001) and extranodal invasion (p=0.003) were significantly associated with contralateral paratracheal LNM in univariate analysis. Multivariate analysis showed that male sex (p=0.005, OR=17.545), T2 disease (p=0.003, OR=34.317), inferior pole tumor (p=0.022, OR=8.289), near isthmus tumor (p=0.001, OR=40.229), aggressive pathology (p=0.027, OR=48.063), pretracheal LNM (p=0.002, OR=14.235) and >5 metastatic lymph nodes (p=0.025, OR=23.426) were independent risk factors for contralateral paratracheal LNM.ConclusionMale sex, T2 disease, a tumor located near the isthmus or inferior pole, aggressive pathology, pretracheal LNM and >5 metastatic lymph nodes were predictive factors for contralateral paratracheal LNM in unilateral cT1N1a or cT2N1a PTC. These data may be useful to identify targets for surveillance or develop therapeutic interventions for patients with CCND.

Pretracheal–laryngeal lymph nodes in frozen section predicting contralateral paratracheal lymph nodes metastasis

BackgroundThere has been an ongoing debate concerning the predictors of contralateral paratracheal lymph nodes metastasis (LNM) in unilateral papillary thyroid cancer (PTC). This study aimed to explore the value of pretracheal–laryngeal lymph nodes (LNs) in frozen section in predicting contralateral paratracheal LNM. MethodsA total of 242 patients with unilateral PTC were enrolled in this prospective study. Patients who underwent total thyroidectomy and bilateral central lymph nodes dissection (LND) were divided into two groups according to positive or negative contralateral paratracheal LNs. Patients’ demographics and clinicopathological features were compared between the two groups. Validity indexes and consistency of pretracheal–laryngeal LNs in frozen sections were calculated. ResultsLNM rates in central, ipsilateral paratracheal, pretracheal–laryngeal, and contralateral paratracheal regions were 55.37%, 47.03%, 23.55% and 14.05%, respectively. Only pretracheal–laryngeal LNM, regardless of whether detected in frozen or paraffin sections, were independent risk factors for contralateral paratracheal LNM (OR = 2.707; 95% CI 1.062–6.902; P = 0.037 in frozen section; OR = 3.072; 95% CI 1.248–7.560; P = 0.015 in paraffin section). The sensitivity, specificity, false-negative rate, false-positive rate, accuracy rate, and Kappa value of pretracheal–laryngeal LNM in frozen sections for predicting pretracheal–laryngeal LNM were 87.72%, 100%, 12.28%, 0%, 97.11% and 0.916 respectively, while those for predicting contralateral paratracheal LNM were 85,29%, 89.90%, 14.71%, 10.10%, 89.22%, and 0.618 respectively. ConclusionPretracheal–laryngeal LNs in frozen section accurately predicted contralateral paratracheal LNM, which could allow the identification of patients who can benefit from an extended central LND.

Rabbit VX2 lung tumor models can form early nodal metastases

BackgroundThe rabbit squamous cell cancer line, VX2, has been used to generate various tumor models in rabbits. It is notable for its ability to generate nodal metastases. However, the timing and extent of nodal metastases vary by primary inoculation site and methodology. The development of metastases specifically in lung cancer models has not been well-described. We sought to characterize the generation of nodal metastases in rabbit transbronchial VX2 lung tumor models.MethodsRabbit VX2 lung tumor models were created in the right lung via transbronchial injection and serially imaged by computed tomography. Rabbits (n = 15) were sacrificed from between 5 and 24 days post-inoculation for collection of the ipsilateral and contralateral paratracheal lymph nodes. These underwent histopathological evaluation for metastases using hematoxylin and eosin as well as cytokeratin AE1/AE3 immunohistochemical staining.ResultsNodal metastases were detectable as early as 1 week after inoculation but were more prevalent with longer inoculation; all rabbits at > 2 weeks post-inoculation had nodal metastases. Contralateral metastases were in general seen later than ipsilateral metastases. Lymph node volume did not predict the likelihood of nodal metastases (p = 0.4 and p = 0.07 for ipsilateral and contralateral nodal metastases, respectively), but primary tumor volume was significantly associated with the likelihood of nodal metastases (p = 0.001 and p = 0.005 for ipsilateral and contralateral nodal metastases, respectively). Ipsilateral metastases were detectable at a tumor diameter of 1 cm; contralateral metastases were more variable but in general required a tumor diameter of 2 cm.ConclusionsRabbit transbronchial VX2 lung tumor models generate nodal metastases relatively early after inoculation. These results suggest such models may be valuable tools in the investigation of novel therapeutic modalities relevant for the treatment of both early-stage and locally advanced lung cancer.

Optimal extent of prophylactic central neck dissection for papillary thyroid carcinoma: Comparison of unilateral versus bilateral central neck dissection

The aim of the study was to determine the optimal extent of prophylactic central neck dissection (pCND) in papillary thyroid carcinoma (PTC). We studied 384 patients with clinically node-negative unilateral PTC who had undergone total thyroidectomy with pCND. Of these, 169 patients underwent unilateral pCND, and 215, bilateral pCND. Age, sex, and TNM stage did not differ between the two groups. The rates of occult central lymph node metastasis were 34.3% and 37.2% in the unilateral and bilateral pCND groups, respectively (p=0.558). Metastasis to the contralateral paratracheal lymph node occurred in 4.2% of the bilateral pCND group. Major complication rates did not differ between the two groups, except for transient hypoparathyroidism, which was higher in the bilateral group (43.7% vs. 33.7%, p=0.047). Stimulated thyroglobulin and RAI ablation uptake rates were similar in the two groups, as were recurrence and disease-free survival. Contralateral paratracheal node dissection may be not indicated for prophylactic central neck dissection in clinically node-negative unilateral PTC because the rate of contralateral paratracheal node metastasis is low and transient hypoparathyroidism is higher following bilateral dissection.

The risk factors for contralateral paratracheal lymph node metastases in papillary thyroid cancer

The risk factors for contralateral paratracheal lymph node metastases in papillary thyroid cancer Objective: Lymph node metastasis is frequently seen in papillary thyroid cancer. In the present study, we aimed to evaluate the rate and risk factors for the contralateral paratracheal lymph node metastasis in papillary thyroid cancer and to evaluate the effect of risk factors on the extent of the lymphatic dissection. Materials and Methods: Twenty-seven patients (19 female, 8 male) with a median age of 44 (range 16-75), who underwent total thyroidectomy with central neck dissection with or without therapeutical lateral neck dissection were examined. The effects of the age, gender, extrathyroidal extension, multifocality, bilaterality, lymphovascular invasion, T stage, prelaryngeal, pretracheal, ipsilateral paratracheal and lateral lymph node metastasis on the contralateral paratracheal metastasis were evaluated. ‘Chi-square’ and ‘Fisher’s exact’ tests were used for statistical analyses. Results: All patients underwent total thyroidectomy with bilateral central neck dissection. Additionally 12 patients out of 27 underwent therapeutical lateral neck dissection. T stages were classified as T1: 16 (59.3%), T2: 7 (25.9%), T3: 4 (14.8%) respectively. The occurance of contralateral paratracheal metastasis was found significantly higher in the cases having lateral metastasis (100% vs 47.6; p=0.05). Conclusions: Lymph node metastasis is frequently seen in papillary thyroid cancer and primarily occurs in the ipsilateral paratracheal area. The rate of contralateral paratracheal metastasis is higher in the patients with lateral lymph node metastasis. The lateral lymph node metastases detected pre or peroperatively should be considered for the bilateral central neck dissection.

Occult Nodal Disease Prevalence and Distribution in Recurrent Laryngeal Cancer Requiring Salvage Laryngectomy.

The indications for neck dissection concurrent with salvage laryngectomy in the clinically N0 setting remain unclear. Our goals were to determine the prevalence of occult nodal disease, analyze nodal disease distribution patterns, and identify predictors of occult nodal disease in a salvage laryngectomy cohort. Case series with planned data collection. Tertiary academic center. Patients with persistent or recurrent laryngeal squamous cell carcinoma (LSCC) after radiation/chemoradiation failure undergoing salvage laryngectomy with neck dissection. We analyzed a single-institution retrospective case series of patients between 1997 and 2014 and identified those who had clinically N0 (cN0) necks (n = 203). Clinical and pathologic data, including nodal prevalence and distribution, were collected and statistical analyses performed. Overall, cN0 necks had histologically positive occult nodes in 17% (n = 35) of cases. Univariate predictors of occult nodal positivity included recurrent T4 stage (34% T4 vs 12% non-T4; P = .0003) and supraglottic subsite (28% supraglottic vs 10% nonsupraglottic; P = .0006). Histologically positive nodes associated with supraglottic primaries were most frequently positive in ipsilateral levels II and III (17% and 16%). Positive nodes for glottic LSCC were most frequently positive in the ipsilateral and contralateral paratracheal nodes (11% and 9%). Histologically positive occult nodes are identified in 17% of cN0 patients undergoing salvage laryngectomy with neck dissection. Occult nodal disease varies in frequency and distribution based on tumor subsite. Predictors of high (>20%) occult nodal positivity include T4 tumors and supraglottic subsite. In glottic LSCC, the most frequent sites of occult nodal disease are the paratracheal nodal basins.

Predictive factors and pattern of central lymph node metastasis in unilateral papillary thyroid carcinoma.

Prophylactic central neck dissection (CND) for papillary thyroid carcinoma (PTC) remains controversial. The aim of this study was to evaluate the patterns and predictive factors of central lymph node metastasis in cases of PTC that were clinically determined to be node negative. We studied 485 patients who have unilateral PTC without clinical lymph node metastasis and underwent total thyroidectomy and prophylactic bilateral CND from 2003 to 2012, retrospectively. The frequency, subsite and predictive factors of central lymph node metastasis were analyzed. In total, 166 (32.4%) patients had occult central lymph node metastases. The most common subsite of central node metastases was the ipsilateral paratracheal lymph node (26.0%), followed by pretracheal (12.5%), prelaryngeal (5.0%), and contralateral paratracheal (3.9%) lymph nodes. The tumor size larger than 0.5cm (p=0.003), age under 45 (p<0.001) and extrathyroidal extension (p=0.028) were associated with ipsilateral central compartment metastasis in multivariate analysis. Contralateral central node metastasis was associated with tumor size >3cm, age under 45, and multifocality and ipsilateral central node metastasis in univariate analysis, but it was associated with only ipsilateral central node metastasis in multivariate analysis (p=0.001). Prophylactic CND might be considered for PTC patients with large tumor size or extrathyroidal extension based on rates of lymph node metastasis. Unilateral CND might be appropriate as prophylactic CND due to the low metastatic rate to the contralateral paratracheal node.

Predictive factors of contralateral paratracheal lymph node metastasis in unilateral papillary thyroid carcinoma.

e17005 Background: Most of unilateral papillary thyroid carcinoma (PTC) metastasize to ipsilateralparatracheal lymph nodes(LNs) while some had contralateral paratracheal LN involved. The aim of thi...

Predictive factors of contralateral paratracheal lymph node metastasis in unilateral papillary thyroid carcinoma

BackgroundMost of unilateral papillary thyroid carcinoma (PTC) metastasize to ipsilateral paratracheal lymph nodes (LNs) while some had contralateral paratracheal LN involved. The aim of this study was to analyze the predictive factors of contralateral paratracheal LN metastasis in unilateral PTC. MethodsData on 332 patients with unilateral PTC who underwent total/near total thyroidectomy and bilateral central neck dissection (CND) with/without lateral neck dissection were collected retrospectively. Patients' demographics, the extent of surgeries, and the pathological status of LNs and primary tumor were analyzed. ResultsA total of 332 patients (67 male and 265 female) were included. Contralateral paratracheal LN metastasis was found in 68 (68/332, 20.5%) patients. Tumor size (>1 cm) (P < .001), capsular/extracapsular invasion (P < .001), pretracheal/prelaryngeal LN metastasis (P < .001), lateral neck LN metastasis (P < .001) and ipsilateral paratracheal LN metastasis (P < .001) was significantly associated with contralateral paratracheal LN metastasis on univariate analysis. Multivariate analysis showed that tumor size (>1 cm) (P = .013), capsular/extracapsular invasion (P = .009), pretracheal/prelaryngeal LN metastasis (P = .021) and lateral neck LN metastasis (P = .002) were independent risk factors of contralateral paratracheal LN metastasis. ConclusionPrimary tumor size >1 cm, capsular/extracapsular invasion, pretracheal/prelaryngeal LN metastasis and lateral neck LN metastasis are predictive factors of contralateral paratracheal LN metastasis in unilateral PTC, which may help to determine the optimal extent of CND in patients with PTC.

Predictive Factors of Contralateral Paratracheal Lymph Node Metastasis in Papillary Thyroid Cancer: Prospective Multicenter Study

To analyze patterns of central lymph node (LN) metastasis to specific compartments in the neck and predictive factors of contralateral paratracheal LN metastasis in patients who underwent prophylactic bilateral central LN dissection for papillary thyroid cancer (PTC). Prospective study. Multitertiary centers. One hundred forty consecutive patients underwent total thyroidectomy and prophylactic bilateral central LN dissection for unilateral PTC without evidence of central LN metastatic disease based on preoperative ultrasound imaging. The central LN compartment was divided into prelaryngeal, ipsilateral/contralateral paratracheal, and pretracheal regions. The patterns of central LN metastasis and clinicopathologic variables for predicting contralateral metastasis were analyzed. Fifty-one (36.4%) of 140 patients had nodal involvement in the central compartment. Twelve (23.5%) patients had ipsilateral paratracheal LN metastasis, 17 (33.3%) had ipsilateral paratracheal and pretracheal LN metastasis, 14 (27.5%) had bilateral paratracheal LN metastasis, 9 (17.6%) had pretracheal-only LN metastasis, and 8 (15.7%) had prelaryngeal LN metastasis. Ipsilateral paratracheal LN metastasis was found to independently predict contralateral paratracheal LN metastasis in patients without central LN metastatic disease. Contralateral paratracheal LN metastasis is associated with ipsilateral paratracheal LN metastasis. This information may help to determine the optimal extent of prophylactic central LN dissection in patients with PTC.

Complications of Central Neck Dissection in Patients with Papillary Thyroid Carcinoma: Results of a Study on 1087 Patients and Review of the Literature

Prophylactic central neck dissection (CND) has been proposed in the treatment of patients affected by papillary thyroid carcinoma (PTC) with clinically negative neck lymph nodes. The procedure allows pathologic staging of lymph nodes of the central compartment and treatment of the micrometastases. Nevertheless, the morbidity that its routine use adds to the total thyroidectomy must be taken into account. The aim of this study was to characterize the morbidity that CND adds to the total thyroidectomy. This was a retrospective study of 1087 patients with PTC and clinically negative neck lymph nodes. Patients were divided into three study groups: Group A, total thyroidectomy; Group B, total thyroidectomy and ipsilateral CND; Group C, total thyroidectomy and bilateral CND. Primary endpoints of the study were evaluated by comparing the rates of transient and permanent recurrent laryngeal nerve (RLN) injury and hypoparathyroidism in the three study groups. Analysis of data showed no significant differences in the rate of transient (Group A: 3.6%, Group B: 3.9%, and Group C: 5.5%; p=0.404) and permanent (Group A: 1%, Group B: 0.5%, and Group C: 2.3%; p=0.099) RLN injury between the three study groups. Both ipsilateral CND and bilateral CND were associated with a higher rate of transient hypoparathyroidism (Group: A 27.7%, Group B: 36.1%, and Group C: 51.9%; p=0.014; odds ratio [OR]: 1.477; 95% confidence interval [CI]: 1.091-2.001; p<0.001; OR: 2.827; 95% CI: 2.065-3.870, respectively). Bilateral CND had a higher rate of permanent hypoparathyroidism (Group A: 6.3%, Group B: 7%, and Group C: 16.2%; p<0.001; OR: 2.860; 95% CI: 1.725-4.743). The increased rates of transient and permanent hypoparathyroidism in our series suggest a critical review of indications for the routine use of prophylactic CND for PTC. Prophylactic CND ipsilateral to the tumor associated with total thyroidectomy may represent an effective strategy for reducing the rate of permanent hypoparathyroidism. Concomitant completion contralateral paratracheal lymph node neck dissection should be performed in presence of lymph node metastasis on intraoperative frozen-section pathology. This approach limits the use of bilateral CND to patients with intraoperative pathological findings of lymph node metastases.

The impact of paratracheal lymph node metastasis in squamous cell carcinoma of the hypopharynx

The aim of this study was to analyze the prevalence and prognostic importance of paratracheal lymph nodes in squamous cell carcinoma of the hypopharynx. A retrospective review of 64 previously untreated patients with squamous cell carcinoma (SCC) of the hypopharynx that underwent surgery was performed. Ipsilateral paratracheal lymph node metastases occurred in 22% (14 out of 64) and the mean number of paratracheal lymph nodes dissected per side was 2.3 (range 1–6). Contralateral paratracheal lymph node metastases were present in 2% (1 out of 42). Sixty-seven percent with postcricoid SCC and 22% with pyriform sinus SCC developed clinical node-positive ipsilateral paratracheal lymph node metastases, whereas 11% with posterior pharyngeal wall SCC developed paratracheal metastases. There was a significant correlation between paratracheal lymph node metastasis and cervical metastasis (p = 0.005), and the primary tumor site (postcricoid, 57.1%; pyriform sinus, 20.0%; posterior pharyngeal wall, 8.3%) (p = 0.039). Patients with no evidence of paratracheal lymph node metastasis may have a survival benefit (5-year disease-specific survival rate, 60 vs. 29%). However, this result did not reach statistical significance (p = 0.071). The patients with SCC of the postcricoid and/or pyriform sinus were at risk for ipsilateral paratracheal lymph node metastasis; furthermore, patients with paratracheal node metastasis had a high frequency of cervical metastasis and a poorer prognosis. Therefore, routine ipsilateral paratracheal node dissection is recommended during the surgical treatment of patients with SCC of the postcricoid and/or pyriform sinus with clinical node metastases.

Central Cervical Nodal Metastasis from Papillary Thyroid Microcarcinoma: Pattern and Factors Predictive of Nodal Metastasis

Although several factors are thought to predict the occurrence of lymph node metastases from papillary thyroid microcarcinoma (PTMC), the pattern of nodal metastasis has been rarely studied. We evaluated the pattern and factors predictive of central cervical metastasis from PTMC. Seventy-two patients with PTMC underwent total thyroidectomy and central neck dissection, including three who underwent therapeutic modified radical neck dissection. Lymph node involvement was analyzed by neck subsite, and clinicopathologic variables predictive of nodal metastasis were determined. Central and lateral nodal metastases were found in 29 (40.3%) and 3 (4.2%) patients, respectively, and ipsilateral paratracheal, pretracheal, superior mediastinal, and contralateral paratracheal lymph node metastases in 27 (37.5%), 8 (11.1%), 4 (5.6%), and 1 (1.4%), respectively. Sex, age, tumor size, multifocality, bilaterality, extracapsular invasion, lymphovascular invasion, and MACIS (metastases, age, completeness of resection, invasion, size) for central node metastasis were not predictive of metastasis (P > .1). Temporary and permanent hypocalcemia was observed in 17 (23.6%) and 1 (1.4%) patients, respectively, and transient vocal fold paralysis in 1 (1.4%). Despite the absence of palpable neck nodes, PTMC is associated with a high rate of central lymph node metastasis to ipsilateral and pretracheal subsites. No clinicopathologic factor predicted nodal metastasis. In patients with PTMC involving one lobe and positive nodes, neck dissection may exclude the contralateral side.

Extent of Prophylactic Lymph Node Dissection in the Central Neck Area of the Patients with Papillary Thyroid Carcinoma: Comparison of Limited Versus Comprehensive Lymph Node Dissection in a 2-Year Safety Study

To compare the "comprehensive" (including bilateral paratracheal, pretracheal, prelaryngeal lymph nodes) (CCND) with "limited" (saving contralateral paratracheal lymph nodes) central node dissection (LCND) for postoperative complications and disease recurrence rate in sonographically node-negative papillary thyroid carcinomas. From 2003 to 2005, 114 consecutive patients, diagnosed as sonographically node-negative thyroid papillary carcinomas, were included retrospectively. Among them, the LCND was performed in 56 patients and CCND in 58 patients, in combination with total thyroidectomy, based on the operator-dependent decision. We compared the complication rates and the recurrence rates between these two groups with a mean follow-up duration of 2 years. Transient hypocalcemia was more frequent in the CCND group than in the LCND group (48.3% vs 26.8%, P = .02, odds ratio [OR] = 2.55). However, the other complication rates were similar in the two groups. In addition, the immediate postoperative reduction of parathyroid hormone (PTH) was more evident in the CCND group. The postoperative PTH levels increased up to a similar level (12.4 vs 11.8 pg/mL) over 6 months. The incidence of permanent hypocalcemia did not differ significantly between the two groups. Four (7.1%) and five recurrences (8.6%) were found in two groups, respectively, implying similar oncological safety during the 2-year follow-up. The LCND with total thyroidectomy could be an alternative treatment option for node-negative papillary thyroid carcinomas, because LCND had fewer short-term hypocalcemia and similar oncological outcomes during the 2-year follow-up. Further study enrolling a large number of patients with long-term follow-up is needed.

Localization of cervical node metastasis of papillary thyroid carcinoma.

Precise localization of cervical node metastasis of papillary thyroid carcinoma is rarely described. The aim of this retrospective study was to map their cervical involvement. Between 1974 and 1996 a series of 119 patients had total thyroidectomy with bilateral cervical lymph node dissection. Patients who had secondary node dissection for a cervical recurrence were excluded. Eight node sites were distinguished (ipsilateral and contralateral): paratracheal, mid-jugular, supraclavicular, subdigastric. All pathologic specimens were reviewed by a single pathologist. Twenty-five patients had lymph node involvement clinically before surgery. Seventy-two (60.5%) had cervical metastasis (N+: node positive patients), with bilateral involvement in 28 cases. In cases of bilateral thyroid tumor localization, ipsilateral dissection designated the side with the largest nodule. The main ipsilateral involved sites were paratracheal (60 patients), mid-jugular (44 patients), and supraclavicular (26 patients). Contralateral paratracheal nodes were involved in 25 patients and mid-jugular nodes in 12. Among the N+ patients, node involvement was absent in 11 cases at paratracheal, 28 jugular, and 46 subclavicular sites. Cervical node metastases concerned 60.5% of the patients, with bilateral involvement in 40.8% of the N+ patients. Ipsilateral paratracheal and jugular sites were most frequently involved. The lateral compartment was sometimes involved independent of the central compartment.

Risk of bilateral cervical lymph node metastases in papillary thyroid cancer

We evaluated the risk of bilateral or contralateral cervical lymph node metastases in 135 patients with papillary thyroid cancer who underwent bilateral neck dissection. We confirmed that bilateral jugular lymph node metastases were frequent in patients with obvious carcinoma in both lobes of the gland, in those with cancers arising in the isthmus, in those with clinically detectable bilateral lymphadenopathy, and in those with recurrent thyroid cancer. However, only 24% of the patients who had cancer clinically confined to one lobe with no bilateral or contralateral lymphadenopathy had histologically detected bilateral or contralateral jugular lymph node metastases. But the occurrence of contralateral jugular lymph node metastases was significantly correlated with both clinical lymphadenopathy in the ipsilateral neck and contralateral paratracheal lymph node metastases. Bilateral lymph dissection might be beneficial for these patients.