Optimal extent of lateral neck dissection for well-differentiated thyroid carcinoma with metastatic lateral neck lymph nodes: A systematic review and meta-analysis

Preoperative Ultrasonography Predicts Level II Lymph Node Metastasis in N1b Papillary Thyroid Carcinoma: Implications for Surgical Planning

PURPOSE

To investigate whether preoperative ultrasonographic (US) features of the index cancer and metastatic lymph nodes (LNs) are associated with level II LN metastasis in N1b papillary rmfthyroid carcinoma (PTC) patients.

MATERIALS AND METHODS

We enrolled 517 patients (mean age, 42 [range, 6-80] years) who underwent total thyroidectomy and lateral compartment LN dissection between January 2009 and December 2015. We reviewed the clinicopathologic and US features of the index cancer and metastatic LNs in the lateral neck. Logistic regression analysis was performed to analyze features associated with level II LN metastasis.

RESULTS

Among the patients, 196 (37.9%) had level II metastasis on final pathology. In the preoperative model, larger tumor size (odds ratios [ORs], 1.031; 95% confidence interval [CI]: 1.011-1.051, p = 0.002), nonparallel tumor shape (OR, 1.963; 95% CI: 1.322-2.915, p = 0.001), multilevel LN involvement (OR, 1.906; 95% CI: 1.242-2.925, p = 0.003), and level III involvement (OR, 1.867; 95% CI: 1.223-2.850, p = 0.004), were independently associated with level II LN metastasis. In the postoperative model, non-conventional pathology remained a significant predictor for level II LN metastasis (OR, 1.951; 95% CI: 1.121-3.396; p = 0.018), alongside the presence of extrathyroidal extension (OR, 1.867; 95% CI: 1.060-3.331; p = 0.031), and higher LN ratio (OR, 1.057; 95% CI: 1.039-1.076; p < 0.001).

CONCLUSIONS

Preoperative US features of the index tumor and LN may be helpful in guiding surgery in N1b PTC. These findings could enhance preoperative planning and decision-making, potentially reducing surgical morbidities by identifying those at higher risk of level II LN metastasis and tailoring surgical approaches accordingly.

Feasibility of remote-access and minimally invasive video-assisted approaches in lateral neck dissection for papillary thyroid carcinoma: A systematic review and network meta-analysis

BACKGROUND

This study was conducted to evaluate the feasibility and surgical outcomes of minimally invasive video-assisted thyroidectomy (MIVAT) and three remote-access approaches, namely the robotic bilateral axillo-breast approach (BABA-R), endoscopic breast-chest approach (BCA-E), and robotic gasless transaxillary approach (GTAA-R) in lateral neck dissection for papillary thyroid carcinoma, compared with conventional transcervical approach (CTA).

METHODS

The literature search was conducted in the PubMed, EMBASE, and Cochrane Library databases, covering the period January 2000 to February 2024. A systematic review and network meta-analysis were performed to compare surgical feasibility, safety, and oncologic outcomes between approaches.

RESULTS

Fourteen articles on lateral neck dissection in patients with papillary thyroid carcinoma were included after systematic screening. The number of removed and metastatic lateral lymph nodes, the extent of lateral neck dissection, the rate of transient recurrent laryngeal nerve palsy and hypoparathyroidism, serum-stimulated thyroglobulin levels, and recurrence were not significantly different between the MIVAT and three remote-access approaches. Additionally, these were comparable to those of the CTA. However, the MIVAT and remote-access approaches took a longer operative time but provided superior cosmetic outcomes compared to the CTA.

CONCLUSION

Lateral neck dissection using the MIVAT and three remote-access approaches was feasible and comparable to CTA in the number of lymph nodes removed, complications, stimulated thyroglobulin level, and recurrence. The MIVAT and remote-access approaches lasted longer but provided significantly superior cosmetic outcomes compared to the CTA.

Prospective application of a prediction model for lateral lymph node metastasis in papillary thyroid cancer patients with central lymph node metastasis

Objective

This study aimed to develop and apply a prediction model to estimate the probability of lateral lymph node metastasis (LLNM) in patients with cN0 unilateral papillary thyroid carcinoma (PTC) with central lymph node metastasis (CLNM).

Setting

All study data were collected from a single tertiary hospital.

Methods

Univariable and multivariable logistic regression analyses were used to explore independent predictors of LLNM in the derivation and internal validation cohorts, which were used to construct and validate a nomogram. Another 96 patients were included prospectively to evaluate the efficacy of this nomogram.

Results

Maximum tumor diameter greater than 1.0 cm (OR, 2.712; 95% CI, 1.412-5.210), multifocality (OR, 2.758; 95% CI, 1.120-6.789), the number of CLNM ≥3 (OR, 2.579; 95% CI, 1.315-5.789), CLNM ratio ≥0.297 (OR, 2.905; 95% CI, 1.396-6.043), and tumors located in the upper portion (OR 2.846, 95% CI 1.151-7.039) were independent predictors associated with LLNM. The prediction model showed excellent discrimination with an AUC of 0.731 (95% CI, 0.635-0.827). Novel risk stratification for LLNM was constructed based on this nomogram. In the prospective cohort, we stratified these patients into three risk subgroups: low-, moderate-, and high-risk subgroups and we found that the probability of LLNM was positively correlated with the total points from the nomogram.

Conclusion

This nomogram was applied in prospective clinical practice and distinguished PTC patients with a genuinely high risk of LLNM. Surgeons can use our nomogram to tailor the surgical plan and to credibly determine further postoperative therapy.

Level II lateral neck dissection for papillary thyroid carcinoma: A retrospective cohort study

BACKGROUND

For N1b papillary thyroid carcinoma (PTC) patients, lateral neck dissection encompassing levels Ⅱ-Ⅴ is generally recommended. However, routine level Ⅱ dissection is controversial given the low incidence of metastasis, and potential complications such as increased shoulder syndrome.

METHODS

Retrospective analysis of consecutive patients with papillary thyroid carcinoma who underwent lateral neck dissection at a single institution from January 2019 to April 2021 was performed. Clinicopathological features such as age, gender, tumor location, tumor size, TgAb and TPOAb levels, capsular invasion, multifocality and lymph node metastases were examined to evaluate the occurrence of metastatic Level Ⅱ lymph nodes.

RESULTS

Overall and occult level Ⅱ metastases were observed in 51.83% and 34.84% of cN1b PTC patients. Multivariant analysis showed that primary tumor, location of primary tumor and positive level Ⅴ can serve as independent risk factors of metastasis in level Ⅱ. For cN1b PTC patients not suspected of level Ⅱ lymph nodes preoperatively, independent risk factors for predicting occult level Ⅱ metastases may include the location of primary tumor, positive level Ⅲ and positive level Ⅴ.

CONCLUSION

A significant number of patients with PTC and lateral neck disease experienced Level Ⅱ metastasis, with the location of primary tumor and multilevel lymph node involvement being the independent risk factors. If the tumor is less than 1 cm and located at lower 2/3 lobe, there is minimal possibility of level Ⅱ lymph node metastasis.

Management of surgical diseases of thyroid gland indications of the United Italian Society of Endocrine Surgery (SIUEC)

A task force of the United Italian society of Endocrine Surgery (SIUEC) was commissioned to review the position statement on diagnostic, therapeutic and health‑care management protocol in thyroid surgery published in 2016, at the light of new technologies, recent oncological concepts, and tailored approaches. The objective of this publication was to support surgeons with modern rational protocols of treatment that can be shared by health-care professionals, taking into account important clinical, healthcare and therapeutic aspects, as well as potential sequelae and complications. The task force consists of 13 members of the SIUEC highly trained and experienced in thyroid surgery. The main topics concern clinical evaluation and preoperative workup, patient preparation for surgery, surgical treatment, non-surgical options, postoperative management, prevention and management of major complications, outpatient care and follow-up.

Patterns of lymph node metastasis in level IIB and contralateral level VI for papillary thyroid carcinoma with pN1b and safety of low collar extended incision for neck dissection in level II

OBJECTIVE

To explore relevant clinical factors of level IIB and contralateral level VI lymph node metastasis and evaluate the safety of low-collar extended incision (LCEI) for lymph node dissection in level II for papillary thyroid carcinoma (PTC) with pN1b.

METHOD

A retrospective analysis was performed on 218 patients with PTC with pN1b who were treated surgically in the Head and Neck Surgery Center of Sichuan Cancer Hospital from September 2021 to May 2022. Data on age, sex, body mass index (BMI), tumor location, maximum tumor diameter, multifocality, Braf gene, T staging, surgical incision style, and lymph node metastasis in each cervical subregion were collected. The chi-square test was used for comparative analysis of relevant factors. All statistical analyses were completed by SPSS 24 software.

RESULT

Each subgroup on sex, age, BMI, multifocality, tumor location, extrathyroidal extension, Braf gene, and lymphatic metastasis in level III, level IV, and level V had no significant difference in the positive rate of lymph node metastasis in level IIB (P > 0.05). In contrast, patients with bilateral lateral cervical lymphatic metastasis were more likely to have level IIB lymphatic metastasis than those with unilateral lateral cervical lymphatic metastasis, with a statistically significant difference (P = 0.000). In addition, lymph node metastasis in level IIA was significantly associated with lymph node metastasis in level IIB (P = 0.001). After multivariate analysis, lymph node metastasis in level IIA was independently associated with lymph node metastasis in level IIB (P = 0.010). The LCEI group had a similar lymphatic metastasis number and lymphatic metastasis rate in both level IIA and level IIB as the L-shaped incision group (P > 0.05). There were 86 patients with ipsilateral central lymphatic metastasis (78.2%). Patients with contralateral central lymphatic metastasis accounted for 56.4%. The contralateral central lymphatic metastasis rate was not correlated with age, BMI, multifocality, tumor invasion, or ipsilateral central lymphatic metastasis, and there was no significant difference (P > 0.05). The contralateral central lymphatic metastasis in males was slightly higher than that in females, and the difference was statistically significant (68.2% vs. 48.5%, P = 0.041).

CONCLUSION

Lymphatic metastasis in level IIA was an independent predictor of lymphatic metastasis in level IIB. When bilateral lateral cervical lymphatic metastasis or lymph node metastasis of level IIA is found, lymph node dissection in level IIB is strongly recommended. When unilateral lateral cervical lymphatic metastasis and lymphatic metastasis in level IIA are negative, lymph node dissection in level IIB may be performed as appropriate on the premise of no damage to the accessory nerve. LCEI is safe and effective for lymph node dissection in level II. When the tumor is located in the unilateral lobe, attention should be given to contralateral central lymph node dissection because of the high lymphatic metastasis rate.

Risk factors for level V metastasis in patients with N1b papillary thyroid cancer

BACKGROUND

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer, and its incidence has increased. Lateral lymph node metastasis (LLNM) implies a worse prognosis than central lymph node metastasis, with a higher recurrence rate and decreased disease-free survival. The 2015 American Thyroid Association guidelines recommend compartmental node dissection in patients with LLNM to reduce the risk of recurrence and mortality. The purpose of this study was to identify the risk factors for level V lymph node (LN) metastasis in patients with N1b papillary thyroid cancer (PTC).

METHODS

A total of 110 consecutive patients who underwent total thyroidectomy with lateral neck dissection for PTC between April 2016 and April 2022 were retrospectively enrolled. Based on level V metastasis, 94 patients were divided into two groups, and their clinicopathological characteristics were compared. Univariable analysis were used to assess the factors associated with level V metastasis. Spearman correlation analysis were used to assess the correlation between tumors and LN. The receiver operating characteristic (ROC) curve was used to determine the optimal cutoff value for the number of metastatic LNs at each level for level V metastasis.

RESULTS

The number of metastatic LNs and lymph node ratio (LNR) in level II were significantly associated with level V metastasis (P = 0.011 and 0.001, respectively). The number of metastatic LNs in level II and those in the total number of levels correlated with the number of metastatic LNs in level V (rho = 0.331, 0.325, and P = 0.001, 0.001, respectively). The cutoff value for the number of metastatic LNs in level II was defined as 2.5 (area under the curve = 0.757, sensitivity = 50%, specificity = 82.5%, 95% confidence interval [CI] 0.626-0.889, P = 0.002). Simultaneous 3-level metastasis (level II, III, and IV) and 3-level with ≥ 2.5 metastatic LNs in level II were significantly associated with level V metastasis (P = 0.003 and 0.002).

CONCLUSIONS

The number of metastatic LNs and LNR in level II, simultaneous 3-level metastasis (level II, III, and IV), and 3-level with ≥ 2.5 metastatic LNs in level II were significantly associated with level V metastasis. (P = 0.011, 0.001, 0.003, and 0.002, respectively). In the future, larger-scale multi-institutional studies were needed to find out predictors for level V metastasis.

A nomogram to predict lateral lymph node metastases in lateral neck in patients with medullary thyroid cancer

BACKGROUND

Medullary thyroid cancer (MTC) can only be cured by surgery, but the management of lateral lymph nodes is controversial, especially for patients with cN0+cN1a. To address this challenge, we developed a multivariate logistic regression model to predict lateral lymph node metastases (LNM).

METHODS

We retrospectively collected clinical data from 124 consecutive MTC patients who underwent initial surgery at our institution. The data of 82 patients (from 2010 to 2018) and 42 patients (from January 2019 to November 2019) were used as the training set for building the model and as the test set for validating the model, respectively.

RESULTS

In the training group, the multivariate analyses indicated that male and MTC patients with higher preoperative basal calcitonin levels were more likely to have lateral LNM (P = 0.007 and 0.005, respectively). Multifocal lesions and suspected lateral LNM in preoperative ultrasound (US) were independent risk factors (P = 0.032 and 0.002, respectively). The identified risk factors were incorporated into a multivariate logistic regression model to generate the nomogram, which showed good discrimination (C-index = 0.963, 95% confidence interval [CI]: 0.9286-0.9972). Our model was validated with an excellent result in the test set and even superior to the training set (C-index = 0.964, 95% CI: 0.9121-1.000).

CONCLUSION

Higher preoperative basal calcitonin level, male sex, multifocal lesions, and lateral lymph node involvement suspicion on US are risk factors for lateral LNM. Our model and nomogram will objectively and accurately predict lateral LNM in patients with MTC.

Patterns of Occult Metastasis to Level Va and Vb in Clinically Lateral Node-Positive Papillary Thyroid Carcinoma

BACKGROUND

The optimal extent of therapeutic lateral neck dissection (ND) in papillary thyroid carcinoma (PTC) continues to be debated. We analyzed the frequency, patterns, and predictive factors of occult level Va and Vb metastasis in clinically lateral node-positive PTC patients.

METHODS

We reviewed the data of PTC patients who underwent thyroidectomy and therapeutic lateral ND from level II to V between May 2008 and August 2020. In our study, 46 patients without clinically positive metastatic lymph nodes (LNs) at level V on the preoperative evaluation were included to analyze occult metastasis at level Va and Vb, respectively. Patient demographics, including age, sex, distribution of pathologic LNs, and characteristics of the primary tumors, were reviewed. In addition, clinicopathologic factors associated with occult level Va and Vb metastasis were analyzed.

RESULTS

Of the 46 patients, 14 (30.4%) patients had occult metastases at level Vb. No occult metastases were found at level Va. Clinically positive level II metastasis (p = 0.015) and simultaneous level II, III, and IV metastases (p = 0.010) in the preoperative evaluation were significantly associated with occult level Vb metastasis. Patients without LN metastasis at level IV or with three or fewer metastatic LNs in the lateral neck never had occult LN metastases at level Vb.

CONCLUSIONS

Occult metastasis at level Va is rare in PTC with lateral LN metastasis. Occult metastasis at level Vb may occur in PTC patients with multilevel involvement, including level II and/or four or more lateral LN metastases.

Indications of Superselective Neck Dissection in Patients With Lateral Node Metastasis of Papillary Thyroid Carcinoma

OBJECTIVE

The extent of neck dissection in papillary thyroid carcinoma (PTC) patients with lateral neck metastasis is controversial. This work aims to screen the patients suitable for superselective neck dissections including only levels III-IV.

STUDY DESIGN

Prospective observational cohort study.

SETTING

The study was conducted in a high-volume tertiary care setting.

METHODS

A total of 134 consecutive previously untreated PTC patients with lateral neck metastases and subjected to 154 therapeutic lateral neck dissections (including levels II, III, IV, and VB) between June 2018 and March 2021 were enrolled. Fine-needle aspiration was performed preoperatively at each suspicious neck level. Clinical predictors were analyzed for occult lymph node metastases at levels II and VB.

RESULTS

As a result, 44.8% and 5.8% of neck specimens exhibited metastatic lymph nodes at levels II and VB. In addition, univariate and multivariate analyses showed that the primary tumor in the ipsilateral thyroid upper lobe (P = .016, odds ratio = 3.528) and clinically multiple metastatic lymph nodes in level III-IV (P = .005, odds ratio = 6.414) were independent predictive factors for occult level II metastases. All 3 (1.9%) occult metastases at level VB were found in necks with preoperative multiple lymph node metastases.

CONCLUSIONS

A superselective lateral neck dissection including levels III to IV may be considered in patients with PTC when the preoperative evaluation identifies a single lymph node metastasis located at levels III to IV and the primary tumor is not in the upper lobe of the ipsilateral thyroid.

The Value of Intraoperative Ultrasound in Selective Lateral Cervical Neck Lymphadenectomy for Papillary Thyroid Cancer: A Prospective Pilot Study

(1) Background: Lymph node metastases from papillary thyroid cancer (PTC) are frequent. Selective neck dissection (SND) is indicated in PTC with clinical or imaging evidence of lateral neck nodal disease. Both preoperative ultrasound (PreUS) and intraoperative palpation or visualization may underestimate actual lateral neck nodal involvement, particularly for lymph-nodes located behind the sternocleidomastoid muscle, where dissection may also potentially increase the risk of postoperative complications. The significance of diagnostic IOUS in metastatic PTC is under-investigated. (2) Methods: We designed a prospective diagnostic study to assess the diagnostic accuracy of IOUS compared to PreUS in detecting metastatic lateral neck lymph nodes from PTC during SND. (3) Results: There were 33 patients with preoperative evidence of lateral neck nodal involvement from PTC based on PreUS and fine-needle cytology. In these patients, IOUS guided the excision of additional nodal compartments that were not predicted by PreUS in nine (27.2%) cases, of which eight (24.2%) proved to harbor positive nodes at pathology. The detection of levels IIb and V increased, respectively, from 9% (PreUS) to 21% (IOUS) (p < 0.0001) and from 15% to 24% (p = 0.006). (4) Conclusions: In the context of this study, IOUS showed higher sensitivity and specificity than PreUS scans in detecting metastatic lateral cervical nodes. This study showed that IOUS may enable precise SND to achieve oncological radicality, limiting postoperative morbidity.

Relevance of level IIb neck dissection in patients with papillary thyroid carcinoma

BACKGROUND

Cervical nodal metastasis is a key prognostic factor in patients with papillary thyroid carcinoma. The role of lymph nodes in papillary thyroid carcinoma management and prognosis remains controversial.

METHODS

Level IIb lymph nodes obtained from 44 patients with papillary thyroid carcinoma were histopathologically examined retrospectively. Specimens were classified as ipsilateral or contralateral. The number of dissected nodes and prevalence of level IIb metastasis were compared according to pre-operative clinical nodal stage.

RESULTS

In the node-negative neck, the prevalence of contralateral and ipsilateral IIb nodes was 0 out of 20 and 0 out of 3, respectively. In the node-positive neck, the prevalence of contralateral and ipsilateral IIb nodes was 1 out of 13 (7.70 per cent) and 3 out of 41 (7.32 per cent), respectively. Clinically determined and pathologically confirmed level IIb node negativity were significantly associated. Thirty-four patients (77.3 per cent) developed accessory nerve complications from level IIb dissection.

CONCLUSION

Level IIb neck dissection for papillary thyroid carcinoma may be required if pre-operative examination reveals multilevel, level IIa or suspicious level IIb metastasis.

Risk Factors and a Prediction Model of Lateral Lymph Node Metastasis in CN0 Papillary Thyroid Carcinoma Patients With 1-2 Central Lymph Node Metastases

BACKGROUND

Papillary thyroid cancer (PTC) in clinically lymph node-negative (cN0) patients is prone toward lymph node metastasis. As a risk factor for tumor persistence and local recurrence, lateral lymph node metastasis (LLNM) is related to the number of central lymph node metastases (CLNMs).

METHODS

We performed LLNM risk stratification based on the number of CLNMs for cN0 PTC patients who underwent thyroidectomy and lymph node dissection between January 2013 and December 2018. A retrospective analysis was applied to the 274 collected patients with 1-2 CLNMs. We examined the clinicopathological characteristics of the patients and constructed a LASSO model.

RESULTS

In the 1-2 CLNM group, tumors >10 mm located in the upper region and nodular goiters were independent risk factors for LLNM. Specifically, tumors >20 mm and located in the upper region contributed to metastasis risk at level II. Hashimoto's thyroiditis reduced this risk (p = 0.045, OR = 0.280). Age ≤ 30 years and calcification (microcalcification within thyroid nodules) correlated with LLNM. The LASSO model divided the population into low- (25.74%) and high-risk (57.25%) groups for LLNM, with an AUC of 0.715.

CONCLUSIONS

For patients with 1-2 CLNMs, young age, calcification, nodular goiter, tumor >10 mm, and tumor in the upper region should alert clinicians to considering a higher occult LLNM burden. Close follow-up and therapy adjustment may be warranted for high-risk patients.

Management of Lateral Multiple-Level Metastasis in N1b Papillary Thyroid Microcarcinoma

Background: The optimal extent of therapeutic lateral neck dissection (LND) in the management of N1b papillary thyroid microcarcinoma (PTMC) is still under debate in clinical practice. In this light, our study aims to explore the incidence, patterns, and predictive factors of the lateral multiple-level metastasis in N1b PTMC patients. Methods: The clinical records of 142 patients diagnosed with N1b PTMC who underwent therapeutic LND from July 2015 to November 2018 at our institution were retrospectively reviewed. Univariate and multivariate analyses were conducted to examine the predictive factors associated with lateral multiple-level metastasis. The recurrence-free survival was analyzed and confirmed by Kaplan-Meier plots and log-rank test. Results: The overall frequency of lateral multiple-level metastasis was 50.7% in N1b PTMC patients, and two-level to four-level simultaneous metastasis were present in 26.8, 17.6, and 6.3% patients, respectively. Extrathyroidal extension (ETE) (OR = 5.79, 95% CI, 1.36-24.59; P = 0.017) and the central metastatic lymph node ratio (CLNR) with values equal or higher than 0.61 (OR = 6.18, 95% CI, 2.53-15.09; P < 0.001) served as independent predictors of multiple-level metastasis in N1b PTMC patients. Moreover, locoregional recurrence was significantly higher in the selective neck dissection (SND) group compared to the modified radical neck dissection (MRND) one (HR = 3.65, 95% CI, 1.11-12.00; P = 0.03). Conclusion: Our results show that the lateral multiple-level metastasis was relatively common, and we suggest MRND to be considered for N1b PTMC patients with ETE or CLNR equal or higher than 0.61.

Prediction of level V metastases in papillary thyroid microcarcinoma: a single center analysis

Background

The rate of level V metastases is significantly low and the necessity of routine level V dissection for papillary thyroid microcarcinoma (PTMC) with clinically lateral lymph node metastasis (LNM) is still controversial.

Methods

This study enrolled 114 consecutive PTMC patients with clinically suspected lateral LNM (N1b) who underwent modified radical neck dissection (levels II to V) at Xiangya Hospital of Central South University from September 2016 to July 2019. Univariate and multivariate analyses were performed to investigate the predictive factors of level V metastasis. The area under the receiver operating characteristic (ROC) curve (AUC), accuracy, specificity and sensitivity were used to determine the predictive value.

Results

The overall and occult rate of level V metastasis were 29.82% (34/114) and 7.02% (8/114), respectively. Univariate analysis showed that level V metastasis was significantly associated with gross extrathyroidal extension (ETE), level IV metastasis and 2-level simultaneous metastasis (all P<0.05). Gross ETE (OR =11.916, 95% CI, 1.404-102.19; P=0.023) and level IV metastasis (OR =8.497, 95% CI, 2.119-34.065; P =0.03) served as independent predictors of level V metastasis in N1b PTMC patients. The sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) of gross ETE and level IV metastasis in predicting the level V metastasis were 25.3% vs. 82.4%, 97.5% vs. 73.8%, 82.69% vs. 76.32%, 80% vs. 57.04% and 75% vs. 90.77%, respectively. The AUC of gross ETE was lower than level IV metastasis (0.605 vs. 0.781, P=0.041).

Conclusions

Routine level V dissection is necessary in N1b PTMC patients with level IV metastasis or gross ETE. Compared with gross ETE, level IV metastasis is superior in predicting level V metastasis.

Level IIb lymph node metastasis characteristics and predictive factors for patients with cN1b papillary thyroid carcinoma

BACKGROUND

The aim of the present study was to examine the frequency, characteristics, and risk factors of level IIb lymph node metastases in papillary thyroid carcinoma.

METHODS

We reviewed and collected clinical and pathological records for 954 papillary thyroid carcinoma patients with clinically positive lateral neck node metastasis. Univariate and multivariate analyses were performed to detect risk factors for level IIb lymph node metastasis; a predictive model was built based on multivariate analysis and tested in a validation group.

RESULTS

Level IIb lymph node metastasis was observed in 137 of 954 patients (14.4%). Univariate and multivariate analyses using the training group indicated that gross extrathyroidal extension of the primary tumor, tumor location in the upper pole, and preoperative distant metastasis were 3 independent risk factors for level IIb lymph node metastasis. This model was built and tested in a validation group, and the area under the curve was 0.840 (P < .001). The cutoff of the IIb score was 12, which was tested in the validation group; the sensitivity was 82.1% and the specificity was 95.6%.

CONCLUSION

Level IIb dissection should be performed in select patients with IIb scores ≥12.

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

Background

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

Methods

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

Results

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

Conclusion

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

Routine Lateral Level V Dissection May Not Be Necessary for Papillary Thyroid Microcarcinoma With Lateral Lymph Node Metastasis: A Retrospective Study of 252 Cases

Background: Lateral lymph node metastasis (LLNM) is associated with distant metastasis, locoregional recurrence and cancer-specific mortality, although the prevalence of LLNM among patients with papillary thyroid microcarcinoma (PTMC) is relatively low. The potential benefits and risks of routine lateral level V dissection (LVD) for PTMC with LLNM have not been previously investigated. Methods: A total of 6,880 consecutive PTMC patients who underwent initial surgery at the First Hospital of Jilin University from January 2009 to July 2017 were retrospectively analyzed. A total of 252 N1b PTMC patients were enrolled in our study. Results: The overall and occult metastasis rates in level V lymph nodes were 21.4 and 6.4%, respectively. Patients with N1b PTMC who received LVD did not show a significantly lower disease-free survival (DFS) than that of patients who did not receive LVD [hazard ratio = 1.11 (CI 0.38-3.21); p = 0.85]. Meanwhile, LVD simultaneously increased the hospital stay and cost (p = 0.03; 0.02). Multivariate logistic regression analysis revealed that 3-level simultaneous metastasis in the lateral neck was an independent risk factor for level V metastasis [odds ratio = 8.6 (CI 1.42-51.72); p = 0.02]. Conclusions: Because of the low metastasis rate in level V lymph nodes, the lack of benefit for recurrence, the longer hospital stay and the higher cost associated with LVD, N1b PTMC patients without clinical level V metastasis may not need to undergo routine dissection. Prophylactic LVD may be recommended only for patients with N1b PTMC with 3-level simultaneous metastasis.