Central lymph node characteristics predictive of outcome in patients with differentiated thyroid cancer

The necessity of prophylactic central lymph node dissection in clinically n0 papillary thyroid carcinoma: perspective from the endemic region

BACKGROUND

Prophylactic central lymph node dissection (pCND) in papillary thyroid carcinoma (PTC) is still a matter of debate. Therefore, we aimed to identify the factors affecting central lymph node metastasis (CLNM) in patients with clinically node-negative (cN0) PTC.

METHODS

This retrospective study included 248 patients with cN0 PTC who underwent total thyroidectomy (TT) or TT + pCND. Clinicopathological associations among CLNM, complication rates and the effect of pCND on staging were assessed. Risk factors (RFs) and the pattern of lymph node metastasis (LNM) in PTC patients were studied via multivariate analysis.

RESULTS

A total of 216 patients underwent pCND, and 58.8% (127/216) had positive CLNM. Male patients, aged < 41 years, and those with lymphatic invasion were identified as RFs for CLNM, with odds ratios of 2.59, 2.26, and 4.09, respectively. Among the 216 patients, 65 (30%) had transient hypoparathyroidism (HPT), and 20 (9.3%) had permanent HPT. Transient recurrent laryngeal nerve (RLN) palsy occurred in 15 (6.9%) patients, and permanent RLN palsy occurred in 3 (1.4%) patients. Over 55 years of age, 46.7% of patients were upstaged according to the American Joint Committee on Cancer (AJCC) TNM staging system, and 14.2% (n = 18) of the 127 patients with CLNM were upgraded according to the American Thyroid Association (ATA) risk stratification system (RSS).

CONCLUSION

Taken together, in terms of the high incidence rate of CLNM in cN0 PTC patients; We believe that routine pCND, which can be performed with low morbidity rates, is optimal for cN0 PTC patients during their first treatment, especially for those with RFs for CLNM.

CLINICAL TRIALS NUMBER

NCT05873283.

Lobectomy vs Total Thyroidectomy With Ipsilateral Lateral Neck Dissection for N1b Intermediate-Risk Papillary Thyroid Carcinoma

Importance

The management of papillary thyroid carcinoma (PTC), particularly in cases with clinically apparent lateral neck lymph node metastasis (cN1b), remains an area of debate. The surgical options for PTC, including total thyroidectomy and lobectomy, have distinct impacts on patients' outcomes and quality of life.

Objective

To compare survival and recurrence outcomes between patients who underwent a lobectomy plus ipsilateral lateral neck dissection (LND) and those who underwent a total thyroidectomy plus ipsilateral LND for intermediate-risk cN1b PTC with both primary tumors and lymph node metastases in the ipsilateral neck region.

Design, Setting, and Participants

This retrospective cohort study was conducted at Ito Hospital, Tokyo, Japan. Patients who underwent surgery for PTC between January 2005 and December 2012 were included, and those with high-risk PTCs and concurrent other thyroid cancers were excluded. Data were analyzed from April to August 2024.

Exposures

Lobectomy plus LND vs total thyroidectomy plus LND.

Main Outcomes and Measures

An inverse probability of treatment weighting (IPTW)-adjusted Kaplan-Meier analysis and a Cox proportional hazards regression analysis were performed to compare the patients' overall survival, recurrence-free survival (RFS), and modified RFS (which considered the potential need for a future contralateral lobectomy).

Results

Of 401 included patients, 317 (79.1%) were female, and the median (IQR) age was 47 (36-59) years. A total of 157 patients underwent lobectomy plus ipsilateral LND and 244 underwent total thyroidectomy plus ipsilateral LND. The median (IQR) follow-up time was 13.0 (11.2-15.0) years. The IPTW-adjusted overall survival rates at 5, 10, and 15 years were 98.0% (95% CI, 93.9-99.3), 97.5% (95% CI, 93.2-99.1), and 96.8% (95% CI, 92.2-98.7), respectively, for the lobectomy group vs 99.4% (95% CI, 97.0-99.9), 97.4% (95% CI, 94.4-98.8), and 96.9% (95% CI, 93.3-98.5), respectively, for the total thyroidectomy group (hazard ratio [HR], 1.10; 95% CI, 0.35-3.47). The IPTW-adjusted RFS rates at 5, 10, and 15 years were 93.8% (95% CI, 88.5-96.7), 88.4% (95% CI, 82.0-92.6), and 84.1% (95% CI, 76.8-89.3), respectively, for the lobectomy group vs 95.4% (95% CI, 91.8-97.4), 92.9% (95% CI, 88.8-95.5), and 87.8% (95% CI, 80.8-92.4), respectively, for the total thyroidectomy group (HR, 1.41; 95% CI, 0.79-2.54). The IPTW-adjusted modified RFS rates at 5, 10, and 15 years were 96.7% (95% CI, 92.2-98.6), 93.8% (95% CI, 88.5-96.7), and 88.9% (95% CI, 82.4-93.1), respectively, for the lobectomy group vs 95.4% (95% CI, 91.8-97.4), 92.9% (95% CI, 88.8-95.5), and 87.8% (95% CI, 80.8-92.4), respectively, for the total thyroidectomy group (HR, 0.93; 95% CI, 0.49-1.76).

Conclusions and Relevance

In this study, for these selected intermediate-risk cN1b PTC cases, total thyroidectomy and lobectomy provided comparable outcomes in terms of prognosis and recurrence. These data may help inform future guideline revisions and support joint decision-making between patients and their clinicians.

Nomogram Predicting Progression-Free Survival in Locally Advanced Papillary Thyroid Cancer with Recurrent Laryngeal Nerve Invasion

OBJECTIVES

The recurrence rate of T4a papillary thyroid cancer (PTC) is relatively high, but research on the prognosis of T4a PTC is rarely investigated. This study aims to analyze the prognosis of T4a PTC patients with recurrent laryngeal nerve (RLN) invasion.

METHODS

Univariable and multivariable Cox proportional hazard models were employed to identify prognostic factors for the progression-free-survival (PFS) of PTC patients. A nomogram was constructed based on essential prognostic factors to predict the risk of disease progression in T4a PTC patients with RLN invasion.

RESULTS

A total of 418/602 (69.4%) T4a PTC patients with RLN invasion underwent surgery, the 5-year PFS rate was 89.8%. The multivariable analyses showed that age ≥55 years, preoperative vocal cord paralysis (VCP), microvascular invasion, and the number of cervical lymph node metastases (CLNM) >10 were prognostic risk factors of PFS in T4a PTC patients with RLN invasion. Our nomogram provided good discrimination, with a C-index of 0.778 in the training set and 0.793 in the validation set. No statistical difference (P = .918) was found between PFS and the surgical methods of RLN. By following up on the patient's voice condition, the RLN function was restored in approximately 82.7% of patients after RLN separation.

CONCLUSION

T4a PTC patients with RLN invasion are prone to disease progression under the following conditions: age ≥55 years old, preoperative VCP, microvascular invasion, and CLNM >10. The RLN nerve preservation surgery does not increase the risk of disease progression.

Predictors of treatment response in lymphogenic metastasized papillary thyroid cancer: a histopathological study

BACKGROUND

Lymph node metastases in papillary thyroid cancer (PTC) increase the risk for persistent and recurrent disease. Data on the predictive value of histopathological features of lymph node metastases, however, are inconsistent. The aim of this study was to evaluate the prognostic significance of known and new histopathological features of lymph node metastases in a well-defined cohort of PTC patients with clinically evident lymph node metastases.

METHODS

A total of 1042 lymph node metastases, derived from 129 PTC patients, were reexamined according to a predefined protocol and evaluated for diameter, extranodal extension, cystic changes, necrosis, calcifications, and the proportion of the lymph node taken up by tumor cells. Predictors for a failure to achieve a complete biochemical and structural response to treatment were determined.

RESULTS

The presence of more than 5 lymph node metastases was the only independent predictor for a failure to achieve a complete response to treatment (odds ratio [OR] 3.39 [95% CI, 1.57-7.33], P < .05). Diameter nor any of the other evaluated lymph node features were significantly associated with the response to treatment.

CONCLUSIONS

Detailed reexamination of lymph nodes revealed that only the presence of more than 5 lymph node metastases was an independent predictor of failure to achieve a complete response to treatment. No predictive value was found for other histopathological features, including the diameter of the lymph node metastases. These findings have the potential to improve risk stratification in patients with PTC and clinically evident lymph node metastases.

Analysis of the influence factors of cervical lymph node metastasis in Papillary thyroid carcinoma: A retrospective observational study

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer, and surgery is crucial for curing PTC. PTC patients often experience lymph node metastasis (LNM) in the neck, and central lymph node metastasis (CLNM) significantly affects the recurrence rate of PTC. Therefore, the thoroughness of the surgery is particularly important for the treatment of PTC. However, there is still controversy regarding the choice of surgical approach. This study retrospectively analyzed the clinical data of 69 PTC patients treated at our hospital from December 2019 to April 2022 and clinically analyzed the high-risk factors for neck LNM. In this study, the patients aged ≤ 55 years were examined in which the number of patients with CLNM were 42 cases (80.77%), tumor diameter >2 cm were 15 cases (100%), the multifocal carcinoma were 38 cases (88.37%) and the involvement of membrane were 38 cases (80.85%), the number of patients whose had lateral cervical lymph node metastasis (LLNM), respectively 43 cases (82.69%), 14 cases (93.33%), 39 cases (90.7%) and 40 cases (85.11%),all of these factors were associated with cervical LNM (P < .05), but was not correlation with sex, double lobe carcinoma, extra glandular invasion and hashimoto (P > .05). The patient's age and number of cancers were independent risk factors for LNM in the central region of the neck (P < .05), while the patient's age, tumor size and number of cancers were significant risk factors for LNM in the lateral cervical region (P < .05). We concluded that cervical LNM was related with the high-risk factors of patient's age, tumor size, multifocal carcinoma in PTC. Especially, modified radical cervical dissection or selective cervical dissection was suggested in the PTC patients who were younger than 42.5 years old, with tumor diameter larger than 2 cm and multifocal carcinoma.

A Nod to the Nodes: An Overview of the Role of Central Neck Dissection in the Management of Papillary Thyroid Carcinoma

Lymph node metastasis in thyroid cancer is common and associated with an increased risk of locoregional recurrence (LRR). Although therapeutic central neck dissection is well established, prophylactic central node dissection (pCND) for microscopic occult nodal involvement is controversial and recommendations are based on low-level evidence. The potential benefits of pCND such as reducing LRR and re-operation, refining staging, and improving surveillance are enthusiastically debated and the decision to perform pCND must be weighed up against the increased risks of complications.

The risk of central nodal metastasis based on prognostic factors of the differentiated thyroid carcinoma: a systematic review and meta-analysis study

BACKGROUND AND AIM

Despite improving the 10-year disease-free-survival, prophylactic central neck dissection (pCND) in differentiated thyroid carcinoma (DTC) should only be considered in patients with high risk factors for lymph node (LN) metastasis due to the increases in the risk of postoperative complications. Our aim was to identify the risk factors for central lymph node metastasis (CLNM) in DTC.

METHOD

We searched PubMed, Scopus, Web of science, Cochrane library for eligible studies from inception to November 1, 2021 and a systematic review and meta-analysis were carried out to identify the risk factors for CLNM in DTC.

RESULTS

We included 41 studies with total of 27,741 patients in this study. The pooled results in this meta-analysis showed that these risk factors were significantly associated with CLNM: age < 45 years (odds ratio (OR) 1.64, 95% confidence interval (CI) 1.34-1.99, p < 0.00001), male sex (OR 1.73, 95% CI 1.54-1.93, p < 0.00001), multifocality (OR 1.87, 95% CI 1.59-2.19, p < 0.00001), bilateral disease (OR 1.43, 95% CI 1.15-1.78, p < 0.001), capsular invasion (OR 1.67, 95% CI 1.10-2.54, p < 0.02), lymphovascular invasion (OR 4.89, 95% CI 2.76-8.66, p < 0.00001) and extra-thyroidal extension (OR 2.43, 95% CI 1.97-3.00, p < 0.00001). In addition, young age (< 45 years), male sex, multifocality, and extra-thyroidal extension were significantly associated with large-volume CLNM in clinically N0 DTC patients. However, the presence of Hashimoto's thyroiditis was not a predictors of large-volume CLNM.

CONCLUSION

Young age (< 45 years), male sex, bilateral disease, multifocality, capsular invasion, lymphovascular invasion and extra-thyroidal extension are significantly associated with CLNM and pCND would be expected to have a higher yield in patients with these risk factors.

Correlation between myoferlin expression and lymph node metastasis in papillary thyroid carcinoma

Background

Myoferlin is a multifunctional protein expressed in various normal and cancer cells, with novel oncogenic roles being newly discovered. Recently, correlations have been found between myoferlin expression and unfavorable prognosis in various carcinomas. This study investigated the prognostic role of myoferlin expression in papillary thyroid carcinoma (PTC), specifically that associated with nodal metastasis.

Methods

We collected clinicopathological data and PTC tissues from 116 patients who had been admitted to Gyeongsang National University Hospital in 2010. Immunohistochemical analysis was performed on surgical specimen-derived tissue microarray blocks. Myoferlin expression was graded, and the relationship between expression level and pathological features of tumors based on the American Joint Committee on Cancer staging system was evaluated.

Results

Of the 116 patient samples, 100 cases exhibited positive myoferlin expression. Higher grade of myoferlin expression was correlated with lower T category group (p = .010). Presence of lymph node metastasis was determined to be significantly correlated with low-grade myoferlin expression (p = .019), with no significant difference between pN1a and pN1b tumors.

Conclusions

Our study revealed an adverse correlation between myoferlin expression and pathological features of PTC, evidence of the potential prognostic role of myoferlin in PTC lymph node metastasis.

Frozen section analysis of central lymph nodes in papillary thyroid cancer: the significance in determining the extent of surgery

BACKGROUND

The indolent feature of papillary thyroid cancer (PTC) has recently led to an increase in less aggressive treatment options instead of total thyroidectomy (TT). We aimed to investigate the clinical significance of elective central compartment neck dissection (CCND) with intraoperative frozen analyses of the central lymph nodes (LNs) to determine the surgical extent of unilateral clinically node-negative PTC.

METHODS

We retrospectively reviewed the medical records of 290 patients with unilateral clinically node-negative PTC who underwent surgery and performed frozen analyses of the central LNs from 2020 to 2021 using our own nodal criteria with cut-off size 5 mm. The patients were divided and investigated according to the surgical extent and the National Comprehensive Cancer Network (NCCN) guidelines; diagnostic accuracy of the frozen analyses was estimated.

RESULTS

TT was performed in 16.2% of patients. The TT group had more metastatic nodes with a larger size, higher LN ratio (LNR), and more extranodal extension. The analyses based on the NCCN guidelines showed similar findings, but more completion TT was required compared with our criteria. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the frozen analyses were 94.6%, 100%, 100%, and 96.1%, respectively.

CONCLUSIONS

Elective CCND with intraoperative frozen analyses is a highly reliable procedure that detects occult nodal metastasis in unilateral node-negative PTC patients. Our nodal criteria yielded significant aggressive nodal characteristics in the TT group while yielding less TTs compared with the NCCN guidelines. The concept and clinical significance of small-volume nodal metastasis in PTC should be further investigated.

The localization of thyroid cancers on the thyroid gland is a new risk factor for metastases of perithyroidal, peritracheal and central lymph nodes

OBJECTIVE

Lymph node metastasis is frequently detected in differentiated thyroid cancers. Central dissection is performed to the lymph nodes in patients with microscopic metastases in the intraoperative evaluation. Other indications for central dissections are tumor size and cervical lateral lymph node metastasis. We consider that the localization of thyroid cancer in the thyroid lodge may be another risk factor for central lymph node metastasis. For this reason, the purpose of the present study was to investigate the relations between thyroid cancer localization and lymph node metastasis in differentiated thyroid cancer patients who had no preoperative cervical metastases and who underwent total thyroidectomy, and peritracheal, perithyroidal, and central lymph node dissection.

METHOD

A total of 213 differentiated thyroid cancer cases followed in our general surgery and endocrinology clinic between September 2016 and May 2020 were evaluated retrospectively. Based on the data in the files, the patients who underwent total thyroidectomy, and central, perithyroidal, and peritracheal lymph node dissection were included in the study. The patients were divided into four Groups according to tumor localizations, those with tumors adjacent to the trachea (Group 1), upper thyroid pole (Group 2), thyroid middle part (Group 3), thyroid inferior (Group 4). The demographic characteristics, laboratory parameters, cancer types, and lymph node metastasis rates of the Groups were evaluated.

RESULTS

A total of 84% (179) of the cases had thyroid papillary cancer, 11.73% (25) had thyroid follicular cancer, and 4.2% (9) had poorly differentiated thyroid cancer. The mean age of all patients was found to be 49 ± 8.3 years, and the female/male ratio was 2.4. It was found that the differentiated thyroid cancers metastasized to the perithyroidal, peritracheal, and central lymph nodes at a rate of 57.74%. The distribution of these metastases according to the Groups was; 62.85% in Group 1, 11.53% in Group 2, 43.9% in Group 3, and 88.57% in Group 4. It was also found that 80.32% of the papillary cancer cases and 57.14% of the follicular cancer cases metastasized to central (level VI) lymph nodes in Group 4.

CONCLUSION

The localization of differentiated thyroid cancers is a new risk factor for perithyroidal metastases.

Thyroglobulin in lymph node fine-needle aspiration biopsy washout fluid. A tertiary center experience

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer. Most PTC secretes thyroglobulin, a useful marker in monitoring preoperative staging and postoperative progression; in addition to serum thyroglobulin, fine needle aspiration washout thyroglobulin (FNA-Tg) is also used. Our aim was to determine the cut-off value for FNA-Tg in our center and to describe major discrepancies between FNA-Tg, cytology and pathology results of the lymph nodes. Methods: We retrospectively retrieved from the electronic database of our endocrinology center all the FNA-Tg measurements between December 10, 2019 and September 2021. For each measurement we also retrieved the corresponding sex, FNAB results and the pathology reports. FNA-Tg was measured by ECLIA immunoelectro-chemiluminescent method. Results: There were 58 FNAB and FNA-Tg of suspect cervical lymph nodes in 40 patients. There were 17 cytologically benign lymph nodes of which 13 had low and 4 had high FNA-Tg; 3 non-diagnostic cytology results of which one had high FNA-Tg; 38 PTC metastases of which 6 had low and 32 had high FNA-Tg titers. The cut-off value of FNA-Tg in our center is 10 ng/ml, with a sensitivity of 86.6% (in those with pathology reports available after surgery). Conclusions: Washout TG is useful in suspicious lymph nodes and has added value to cytology in selected cases. The cut-off value of FNA-Tg in our center is 10 ng/ml, with a sensitivity of 86.6%. However, we must consider the possible false negative results that may occur in some histological types of PTC.

Preoperative Evaluation of Central Lymph Nodes in Papillary Thyroid Carcinoma Using High-Resolution Ultrasound and Shear-Wave Elastography

ABSTRACT

The aim of this study was to discuss the diagnostic value of high-resolution ultrasound and virtual touch tissue imaging quantification (VTIQ) for distinguishing metastatic and benign central lymph nodes (CLNs) in patients with papillary thyroid carcinoma. This retrospective study involved 86 pathologically proven benign lymph nodes (LNs) and 118 metastatic LNs in patients with papillary thyroid carcinoma. We analyzed the sonographic features of CLNs (size, shape, distribution, hilum, echogenicity, cystic change, calcification, vascularity, shear-wave velocity [SWV]). The prevalence of sonographic features and the SWV was compared between metastatic and benign CLNs. The size, shape, margin, distribution, presence of hilum, echogenicity, calcification, and vascularity were significantly different between benign and metastatic CLNs (P < 0.05 for all). The mean maximum SWV for malignant CLNs was 3.139 ± 0.408 m/s, whereas that of benign CLNs was 2.418 ± 0.369 m/s (P < 0.05). The cutoff point of the SWV for differentiating benign and malignant LNs was 2.675 m/s. Logistic regression analysis showed that round or irregular shape, aggregation or fusion, calcification, and VTIQ value greater than 2.675 m/s of CLNs were independent risk factors for malignancy, with an odds ratio of 5.77, 3.05, 3.23, and 62.85, respectively. High-resolution ultrasound and VTIQ can provide valuable information for distinguishing metastatic from benign CLNs.

Management of the Neck in Well-Differentiated Thyroid Cancer

PURPOSE OF REVIEW

In this narrative review, we discuss the indications for elective and therapeutic neck dissections and the postoperative surveillance and treatment options for recurrent nodal disease in patients with well-differentiated thyroid cancer.

RECENT FINDINGS

Increased availability of advanced imaging modalities has led to an increased detection rate of previously occult nodal disease in thyroid cancer. Nodal metastases are more common in young patients, large primary tumors, specific genotypes, and certain histological types. While clinically evident nodal disease in the lateral neck compartments has a significant oncological impact, particularly in the older age group, microscopic metastases to the central or the lateral neck in well-differentiated thyroid cancer do not significantly affect outcome. As patients with clinically evident nodal disease are associated with worse outcomes, they should be treated surgically in order to reduce rates of regional recurrence and improve survival. The benefit of elective neck dissection remains unverified as the impact of microscopic disease on outcomes is not significant.

miR-3619-3p promotes papillary thyroid carcinoma progression via Wnt/β-catenin pathway

BACKGROUND

It is well known that the dysregulation of microRNAs (miRNAs) has been identified in papillary thyroid carcinoma (PTC), but their roles in the progression and metastasis of PTC remain unclear. MicroRNA-3619-3p (miR-3619-3p) is associated with cancer progression as an oncogene which is predicted to target at the Wnt/β-catenin signaling pathway. Our study aimed to investigate the role of miR-3619-3p on PTC cell migration and invasion, as well as the underlying mechanisms.

METHODS

The expression of miR-3619-3p in 36 PTC tissues and corresponding tumor-adjacent tissues, as well as 3 PTC cell lines (BCPAP, K1, TPC-1) and the normal thyroid epithelial cell line (N-thy-ori 3-1) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The relationship between miR-3619-3p expression and clinicopathologic status of PTC patients was analyzed. Migration, invasion, and wound healing, were used to evaluate the role of miR-3619-3p in PTC. The activation of β-catenin and the possible molecular pathway were detected by western blotting.

RESULTS

The expression of miR-3619-3p in PTC tissues was significantly higher than the corresponding tumor-adjacent tissues (P<0.01), and its high expression positively correlated with extrathyroidal invasion, multicentricity, and cervical lymph node metastasis. Moreover, the miR-3619-3p was also up-regulated in PTC cell lines when compared to N-thy-ori 3-1. MiR-3619-3p enhanced the capabilities of migration and invasion in PTC cell lines. Furthermore, miR-3619-3p activated Wnt/β-catenin pathway via maintaining the mRNA stability of β-catenin.

CONCLUSIONS

miR-3619-3p promoted PTC cell migration and invasion as an oncogene via activating the Wnt/β-catenin pathway through increasing the stability of β-catenin.

Impact of Extranodal Extension on Risk Stratification in Papillary Thyroid Carcinoma

Background: The current American Thyroid Association risk-stratification system for papillary thyroid carcinoma (PTC) incorporates the number and size of positive lymph nodes (LNs) but places less weight on extranodal extension (ENE). This study investigated how to incorporate ENE into the current system to predict recurrence better in PTC N1 patients. Methods: A total of 369 N1 PTC patients without distant metastasis were enrolled. The combination of number of positive LNs and LNs with ENE that had the highest C-index were identified with multivariable Cox proportional hazards models. ENE number was incorporated into the current system considering the recurrence rate and unadjusted and adjusted hazard ratios (HRs) of the subgroups. Kaplan-Meier curves for recurrence based on current and alternative systems were compared by log-rank test. Results: The recurrence rate for the subgroup with five or fewer positive LNs and one to three ENEs (7/61; 11.5%) was higher than that of the subgroup with five or fewer positive LNs without ENE (5/129; 3.9%; adjusted HR = 3.42 [confidence interval (CI) 0.99-11.75]; p = 0.050). In contrast, adjusted HRs of the subgroup with more than five positive LNs and one to three ENEs (2.33 [CI 0.52-10.35]) or with four or more ENEs (3.86 [CI 1.05-14.17]) were not higher than those of the subgroup with more than five LNs without ENE (4.47 [1.16-17.19]). Incorporating ENE into the current system as an intermediate-risk group yielded a lower log-rank p-value (0.05 vs. 0.01) than the current system. Conclusions: The presence of ENE in low volume LN metastasis confers an intermediate risk of recurrence. Incorporating ENE into the current system allows more accurate decisions regarding further management of PTC N1 patients.

Predictive factors for central lymph node and lateral cervical lymph node metastases in papillary thyroid carcinoma

BACKGROUND

Central lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC) is common. But the association between primary tumor characteristics and specific features of metastatic lymph nodes in PTC has not been fully identified. Determining risk factors for LNM may help surgeons determine rational extent of lymph node dissection.

METHODS

Data from 432 patients who underwent thyroidectomy with cervical lymph node dissection for PTC were retrospectively analyzed. The relationships between LNM to central compartment or lateral compartment and clinicopathologic factors were analyzed. Cox regression model was used to determine the risk factors for recurrence-free survival (RFS).

RESULTS

Central lymph node metastasis (CLNM) and lateral lymph node metastasis (LLNM) were found in 216 (50.0%) and 65 (15.0%) patients, respectively. In the multivariate analysis for CLNM, patients < 45 years of age (OR 2.037, 95% CI 1.388-2.988, P < 0.001), extrathyroidal invasion (OR: 2.144, 95% CI 0.824-5.457, P = 0.011), vascular invasion (OR 13.817, 95% CI 1.694-112.693, P = 0.014), LLNM (OR 2.851, 95% CI 1.196-6.797, P = 0.014) and TNM Stage III-IV (OR 465.307, 95% CI 113.903-1900.826, P < 0.001) were independent predictors for high prevalence of CLNM. In the multivariate analysis for LLNM, tumor size more than 1cm (OR 3.474, 95% CI 1.728-6.985, P < 0.001) and CLNM (OR 5.532, 95% CI 2.679-11.425, P < 0.001) were independent predictors for high prevalence of LLNM. Moreover, tumor with T3-T4 stage, extrathyroidal invasion and CLNM were the significant factors related to the RFS.

CONCLUSION

For patients with pre-operative risk factors of LNM, an accurate preoperative evaluation of central compartment or lateral compartment is needed to find suspicious lymph nodes. And prophylactic lymph node dissection should be performed in patients with high risk of CLNM. Moreover, we suggest performing close follow-up for patients with high risk of RFS.

Independent predictors and lymph node metastasis characteristics of multifocal papillary thyroid cancer

The multifocal papillary thyroid cancer (PTC), with more aggressive and poorer prognosis, is not rare in papillary histotype. Few studies evaluated risk factors and lymph node metastasis in multifocal PTC. The aim of this present study focusing on risk factors and lymph node metastasis characteristics in multifocal PTC was excepted to assist clinical decisions regarding surgery.It was a retrospective study. The 1249 consecutive patients with PTC were reviewed. Of these, 570 patients who met the criteria were selected: 285 with solitary papillary thyroid cancer and 285 with multifocal PTC. The risk factors and lymph node metastasis in multifocal PTC were investigated by univariate and multivariate analysis.Multifocal PTC showed a higher positive rate of capsular invasion, extrathyroidal extension, tumor size >10 mm, pathological T classification, N+ stage, local recurrence, and radioactive iodine ablation (RAI). Capsular invasion (hazard ratio [HR], 1.589; 95% confidence interval [CI],1.352-1.984), advanced pathological T classification (HR, 3.582; 95% CI, 2.184-5.870), and pathological N+ stage (HR, 1.872; 95% CI, 1.278-2.742) were related to increased risk of multifocality and there was a significant increased HR for central neck compartment involvement in male sex (HR, 2.694; 95% CI, 1.740-4.169), advanced pathological T classification (HR, 2.403; 95% CI, 1.479-3.907) and multifocality (HR, 1.988; 95% CI, 1.361-2.906).There is a significant association between capsular invasion, advanced pathological T classification, N+ stage, and multifocal PTC. Total thyroidectomy plus prophylactic bilateral central lymph node dissection should be recommended during surgery due to a stronger predilection for level VI lymph node metastasis in multifocal PTC.

Number of Metastatic Lymph Nodes and Ratio of Metastatic Lymph Nodes to Total Number of Retrieved Lymph Nodes Are Risk Factors for Recurrence in Patients With Clinically Node Negative Papillary Thyroid Carcinoma

OBJECTIVES

The number of metastatic lymph nodes (LNs) and the ratio between the number of metastatic LNs and the total number of retrieved LNs (the LN ratio [LNR]) have been proposed as risk factors for recurrence of papillary thyroid carcinoma (PTC). However, the significance of the number of LNs and the LNR in patients with clinically node negative PTC has not been clearly determined. The purpose of this study is to evaluate their significance.

METHODS

We retrospectively analyzed 382 patients with PTC who had undergone total thyroidectomy with prophylactic central neck dissection (CND) between January 2000 and December 2010. We excluded patients with lobectomy, concurrent lateral compartment neck dissection, a follow-up period less than at least 2 years, number of harvested central LNs less than or equal to one, clinically positive LN, distant metastasis, recurrent cancer or other types of malignancy. The correlations between recurrence and various clinicopathologic characteristics including tumor size, extrathyroidal extension (ETE), stage, number of metastatic central LNs, and the LNR were investigated.

RESULTS

After a mean follow-up period of 82.2±26.4 months, recurrence occurred in 14 patients (3.7%). Tumor size ≥20 mm, maximal ETE, presence of central LN metastasis, number of metastatic LNs ≥2, and LNR ≥0.31 correlated with recurrence in the univariate analysis. However, tumor size ≥20 mm, maximal ETE, number of metastatic LNs ≥2, and LNR ≥0.31 were significantly associated with recurrence in the multivariate analysis (hazard ratio=6.61, 7.17, 3.43, and 11.23, respectively).

CONCLUSION

The LNR and the number of metastatic LNs are independent prognostic risk factors for recurrence in patients with clinically node negative PTC, and these factors can be used to guide postoperative adjuvant therapy and follow-up strategy after prophylactic CND.

Prognostic indicators for papillary thyroid carcinoma

Differentiated thyroid cancer (DTC) includes more than 90% of all thyroid carcinoma and its incidence is growing, mainly due to an increase in the incidence of papillary thyroid cancer (PTC) for the widespread use of neck ultrasonography. Areas covered: Several prognostic factors should be considered during the management of PTC in order to provide the most effective treatment. The most important prognostic factors in PTC include personal and pathological features such as patient's age, gender, hystotype, tumor size, extrathyroidal extension, lymph node involvement, presence of local or distant metastases and molecular analyses. We performed a search in the PubMed database for studies published in English since 1960 using the terms: 'thyroid cancer', 'prognostic factors', 'age', 'gender', 'hystotype', 'tumor size', 'extrathyroidal extension', 'lymph node', 'metastases' and 'molecular analyses'. Expert commentary: Prognostic factors can guide clinicians during the treatment and follow-up of DTC patients, but it is now evident that the risk of recurrence or death must be evaluated periodically, on the basis of individual risk, according to the response to initial therapy or the subsequent therapy required during follow-up.

Prognostic Value of Extranodal Extension in Thyroid Cancer: A Meta-Analysis

PURPOSE

Thyroid cancer is the most common endocrine cancer and its incidence has continuously increased in the last three decades all over the world. We aimed to evaluate the prognostic value of extranodal extension (ENE) of thyroid cancer.

MATERIALS AND METHODS

We performed a systematic search of MEDLINE (from inception to June 2014) and EMBASE (from inception to June 2014) for English-language publication. The inclusion criteria were studies of thyroid cancer that reported the prognostic value of ENE in thyroid cancer. Reviews, abstracts, and editorial materials were excluded, and duplicate data were removed. Two authors performed the data extraction independently.

RESULTS

6 studies including 1830 patients were eligible for inclusion in the study. All patients included in the meta-analysis had papillary thyroid cancer (PTC). Recurrence-free survival was analyzed based on 3 studies. The pooled hazard ratio for recurrence was 2.01 [95% confidence interval (CI) 1.19-3.40, p=0.009]. Disease-specific survival was analyzed based on 3 studies with 973 patients. Patients of PTC with ENE showed 3.37-fold higher risk of death from the disease (95% CI 1.55-7.32, p=0.002).

CONCLUSION

ENE should be considered to be a poor prognostic marker in thyroid cancer; such knowledge might improve the management of individual patients. This might facilitate the planning of appropriate ablation therapy and tailored patient follow-up from the beginning of treatment.

The prognostic value of regional lymph node metastases in patients of Guangdong Province, China with differentiated thyroid cancer: A multicenter retrospective clinical study

Although the prognostic value of nodal metastases in differentiated thyroid cancer remains controversial, it is of interest to evaluate and understand the different characteristics of predictive outcomes.A multicenter retrospective study was conducted in 215 untreated patients with differentiated thyroid cancer from July 1997 to July 2015 in 4 medical centers of Guangdong Province. A total of 107 patients with nodal metastases (group A) were compared to 108 patients without metastases (group B). The 5-year disease-free survival (DFS), overall survival (OS), and postoperative complications in both groups were calculated. Variables predictive of DFS and OS were evaluated in group A.The group A had lower 5-year DFS (69.16%, 11 months) and shorter median time of recurrence than those in group B (87.96%, 8.5 months, respectively, P < 0.001). The incidence of temporary hypoparathyroidism in group A is lower; whereas higher incidence of temporary unilateral vocal cord palsy, permanent hypoparathyroidism, permanent unilateral vocal cord palsy, and bilateral vocal cord palsy in group A were observed. Both univariate and multivariate analyses in group A revealed that age, pathological tumor node metastasis (pTNM) stage, and histology were related to DFS (P < 0.05); while pTNM stage and histology were related to OS only in univariate analyses.Positive nodal metastases have significant prognostic value in patients with differentiated thyroid cancer in Guangdong, China and primarily reduce DFS. Moreover, patients with positive nodal metastases who are >45 years and have higher pTNM stage or follicular histology tend to have poor prognosis. Selective lymph node dissection with appropriate postoperative treatment and frequent follow-up should be accorded to these vulnerable groups of patients.

Surgical Management of Lymph Node Compartments in Papillary Thyroid Cancer

Although papillary thyroid cancer (PTC) commonly metastasizes to cervical lymph nodes, prophylactic central neck dissection is controversial. The primary treatment for lymph node metastases is surgical resection. Patients diagnosed with PTC should be assessed preoperatively by cervical ultrasound to evaluate central and lateral neck lymph node compartments. Sonographically suspicious lymph nodes in the lateral neck should be biopsied for cytology or thyroglobulin levels. Any compartment (central or lateral) that has definitive proof of nodal metastases should be formally dissected at the time of thyroidectomy.

Nodal metastases in thyroid cancer: prognostic implications and management

The significance of cervical lymph node metastases in differentiated thyroid cancer has been controversial and continues to evolve. Current staging systems consider nodal metastases to confer a poorer prognosis, particularly in older patients. Increasingly, the literature suggests that characteristics of the metastatic lymph nodes such as size and number are also prognostic. There is a growing trend toward less aggressive treatment of low-volume nodal disease. The aim of this review is to summarize the current literature and discuss prognostic and management implications of lymph node metastases in differentiated thyroid cancer.

The Impact of Metastatic Lymph Nodes on Risk Stratification in Differentiated Thyroid Cancer: Have We Reached a Higher Level of Understanding?

BACKGROUND

The revised American Thyroid Association (ATA) management guidelines for differentiated thyroid cancer emphasize a variety of clinicopathologic features of metastatic lymph nodes in determining the risk of recurrence. The mere presence of a positive node is not sufficient to confer reliable prognostic significance. The number and size of lymph nodes, as well as the presence of extranodal extension (ENE), impact risk stratification. Moreover, the presence of clinically evident lymph nodes is important for determining risk of recurrence. A patient's place on the risk spectrum has ramifications for the management of differentiated thyroid cancer. However, there are inherent inconsistencies in the identification and characterization of metastatic lymph nodes. Moreover, the significance of ENE must be clarified.

SUMMARY

There are many obstacles to the consistent reporting of metastatic lymph nodes. What constitutes a "clinically evident" lymph node has not been well defined, lacks precision, and varies depending on clinical context, as well as the experience of the surgeon and the ultrasonographer. The number of lymph nodes sampled by surgeons and reported by pathologists may vary from institution to institution. The literature on ENE has been limited by the fact that the definition of ENE has not been standardized. Nevertheless, 17/19 manuscripts reviewed herein suggest that ENE confers a worse prognosis. The ATA risk stratification for metastatic lymph nodes published in the 2015 guidelines combines clinicopathological features that are variably identified and reported across institutions. This review brings into question the significance of the number of nodes with ENE, a factor that is used as an important stratifying variable in the latest guidelines.

CONCLUSIONS

Metastatic lymph nodes do not all carry the same prognostic significance, but a risk assignment based on the ATA guidelines is limited by a lack of standardization in clinical and pathologic definitions, lymph node sampling, and reporting. This study reviews the limitations of prior studies on ENE and concludes that the body of the evidence reported in those studies suggests that ENE increases the risk of recurrence. The impact of ENE in lymph nodes in thyroid cancer risk stratification should be reconsidered.

Role of RAI in the management of incidental N1a disease in papillary thyroid cancer

BACKGROUND

Following total thyroidectomy (TT) for papillary thyroid cancer (PTC), pathological assessment can occasionally reveal incidental perithyroidal lymph nodes (LNs) with occult metastases. These cN0pN1a patients often receive radioactive iodine (RAI) therapy for this indication alone. The aim of this study was to determine the central compartment nodal recurrence-free survival in patients treated without RAI compared to those who received RAI treatment.

METHODS

An institutional database of 3664 previously untreated patients with differentiated thyroid cancer operated between 1986 and 2010 was reviewed. A total of 232 pT1-3 patients managed with TT and no neck dissection were subsequently found to have incidental level 6 LNs on pathology. Patients with other indications for RAI, such as extrathyroidal extension and close or positive margins, were excluded. One hundred and four patients remained for analysis. Kaplan-Meier method was used to determine central neck LN recurrence-free survival (RFS).

RESULTS

The median age of the cohort was 40 years (range 17-83). The median follow-up was 53 months (range 1-211). The median number of positive LNs removed and maximum LN diameter were 1 (range 1-8) and 5 mm (range 1-16 mm), respectively. A total of 67 (64%) patients had adjuvant RAI and 37 (36%) did not. Patients with vascular invasion (P = 0·01), LNs >2 mm (P = 0·07) and >2 positive nodes (P = 0·06) were more likely to be selected for adjuvant RAI therapy. Patients without RAI therapy had similar 5-year central neck LN RFS compared to those treated with RAI: 96·2% vs 94·6%, respectively (P = 0·92).

CONCLUSION

There is no difference in the 5-year central compartment nodal recurrence-free survival in patients treated without RAI compared to those who received RAI treatment.

Pathologic features of metastatic lymph nodes identified from prophylactic central neck dissection in patients with papillary thyroid carcinoma

The importance of pathologic features of metastatic lymph nodes (LNs), such as size, number, and extranodal extension, has been recently emphasized in patients with papillary thyroid carcinoma (PTC). We evaluated the characteristics of metastatic LNs identified after prophylactic central neck dissection (CND) in patients with PTC. We performed a retrospective review of 1,046 patients who underwent unilateral or bilateral thyroidectomy with ipsilateral prophylactic CND. We reviewed the characteristics of the metastatic LNs and analyzed their correlation to the clinicopathologic characteristics of the primary tumor. Cervical LN metastasis after prophylactic CND was identified in 280 out of 1046 patients (26.8 %). The size of metastatic foci (≥2 mm) was independently correlated with primary tumor size (≥1 cm) (p = 0.016, OR = 1.88). Primary tumor size (≥1 cm) was also correlated to the number of metastatic LNs (≥5) (p = 0.004, OR = 3.14) and extranodal extension (p = 0.021, OR = 2.41) in univariate analysis. The size of the primary tumor affects pathologic features of subclinical LN metastasis in patients with PTC. Patients with primary tumors ≥1 cm have an increased risk of larger LN metastases (≥2 mm), an increased number of LN metastases (≥5), and a higher incidence of ENE, which should be considered in decision for prophylactic CND.

Primary tumour characteristics predict the invasiveness of lymph node metastases in papillary thyroid carcinoma patients

OBJECTIVE

This study evaluated whether primary tumour characteristics are associated with specific features of metastatic lymph nodes in papillary thyroid carcinoma patients.

METHOD

A retrospective review of 411 patients with pathologically diagnosed cervical lymph node metastasis was conducted.

RESULTS

A metastatic lymph node focus size of at least 2 mm was independently associated with a primary tumour size of at least 1 cm (hazard ratio 1.962) and with male sex (hazard ratio 1.947). A number of at least five lymph node metastases was independently associated with a primary tumour size of at least 1 cm (hazard ratio 2.863), extrathyroidal extension (hazard ratio 1.737) and male sex (hazard ratio 1.689). Extranodal extension was independently associated with a primary tumour size of at least 1 cm (hazard ratio 2.288), extrathyroidal extension (2.201) and male sex (hazard ratio 1.733).

CONCLUSION

Primary papillary thyroid carcinoma characteristics are related to the pathological features of lymph node metastases.

Prognostic impact of extra-nodal extension in thyroid cancer: A meta-analysis

BACKGROUND AND OBJECTIVES

Lymph node involvement is common in thyroid cancer, but the system of staging does not consider the histological features of lymph node metastases. We conducted a meta-analysis to investigate the prognostic role of extranodal extension (ENE) in thyroid cancer patients.

METHODS

We ran PubMed and SCOPUS searches without language restrictions. Prospective studies reporting data on overall mortality, cancer-specific mortality, or disease recurrence including thyroid cancer patients, in which cases with ENE (ENE+) were compared with those with only intranodal disease (ENE-) were eligible. Data were summarized using risk ratios (RR) for number of deaths/recurrences, and hazard ratios (HR) for time-dependent risks related to ENE+ status, adjusted for potential confounders.

RESULTS

Of 414 hits, 23 studies were eligible and included. Compared to ENE-, patients who were ENE+ had significantly higher rates of all-cause mortality (studies = 8; RR = 3.25; 95%CI: 1.35-2.64, I(2) = 83%) and recurrence (studies = 17; RR = 2.64, 95%CI: 1.93-3.60, I(2) = 73%). Using HRs adjusted for potential confounders, ENE+ status carried a significantly higher risk of all-cause and cancer-specific mortality and disease recurrence.

CONCLUSION

It becomes mandatory to consider ENE in the histopathological examination of surgical samples in thyroid cancer patients, and this factor should be included in future oncological staging systems.

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.

Lateral Neck Lymph Node Characteristics Prognostic of Outcome in Patients with Clinically Evident N1b Papillary Thyroid Cancer

PURPOSE

To identify lateral lymph node (LN) characteristics predictive of outcome in papillary thyroid cancer patients with clinically evident nodal disease.

METHODS

A total of 438 patients with lateral neck metastases from papillary thyroid cancer were identified from an institutional database of 3,664 differentiated thyroid cancers. The number of positive LNs, size of the largest LN, number of positive LNs to total number of LNs removed (LN burden), and presence of extranodal spread (ENS) were recorded. Cutoffs for continuous variables were determined by receiver operating characteristic curves. LN variables predictive of recurrence free survival and disease-specific survival (DSS) were identified by the Kaplan-Meier method and the Cox proportional hazard model.

RESULTS

The median age was 41 years (range 5-86 years). The median follow-up was 65 months (range 1-332 months). Fifty-nine patients developed disease recurrence; these were local in five, regional in 40, and distant in 30 patients. Fifteen patients died of disease. Receiver operating characteristic cutoffs were >10 positive LNs and a LN burden >17 %. No lateral LN characteristics were predictive of DSS. In patients <45 years old, univariate predictors of recurrence were >10 positive nodes (p = 0.049) and LN burden >17 % (p < 0.001). In patients ≥45 years old, >10 positive nodes, LN burden >17 %, and presence of ENS were predictive of recurrence (p = 0.019, p = 0.019, and p = 0.029, respectively).

CONCLUSIONS

LN burden >17 % (1 positive LN in 6 LNs removed) in the lateral neck is predictive for recurrence in patients of all ages, whereas ENS is also prognostic for recurrence in older patients.