Prophylactic level II neck dissection guided by frozen section for clinically node-negative papillary thyroid carcinoma: is it useful?

The diagnosis and management of small and indeterminate lymph nodes in papillary thyroid cancer: preoperatively and intraoperatively

Although thyroid cancer is an indolent tumor with a favorable prognosis, lymph node metastasis (LNM) serves as a major concern for many patients. Because LNM is strongly correlated with recurrence, distant metastasis, and shortened survival, a precise and timely diagnosis and following appropriate management for LNM are necessary. However, significant challenges still exist in the diagnosis of small LNs (<1 cm in diameter), and their low volume makes it difficult to determine whether they are metastatic or benign. Therefore, the diagnostic technique for these small and indeterminate LNs (siLNs) has been one of the leading research subjects in recent years. The implementation of innovative technologies, such as contrast-enhanced ultrasonography, frozen section, and molecular detection, has brought great progress to the diagnosis of siLNs. Meanwhile, the strategies for managing siLNs in clinical practice have evolved considerably over the past several years, with several appropriate options recommended by guidelines. In this review, we aim to provide a systematic overview of the latest studies and potential evidence about effective approaches for detecting and evaluating siLNs. Furthermore, the following management modalities of siLNs in different situations are well discussed.

Predictors of Central Compartment Involvement in Patients with Positive Lateral Cervical Lymph Nodes According to Clinical and/or Ultrasound Evaluation

Lymph node neck metastases are frequent in papillary thyroid carcinoma (PTC). Current guidelines state, on a weak level of evidence, that level VI dissection is mandatory in the presence of latero-cervical metastases. The aim of our study is to evaluate predictive factors for the absence of level VI involvement despite the presence of metastases to the lateral cervical stations in PTC. Eighty-eight patients operated for PTC with level II–V metastases were retrospectively enrolled in the study. Demographics, thyroid function, autoimmunity, nodule size and site, cancer variant, multifocality, Bethesda and EU-TIRADS, number of central and lateral lymph nodes removed, number of positive lymph nodes and outcome were recorded. At univariate analysis, PTC location and number of positive lateral lymph nodes were risk criteria for failure to cure. ROC curves demonstrated the association of the number of positive lateral lymph nodes and failure to cure. On multivariate analysis, the protective factors were PTC located in lobe center and number of positive lateral lymph nodes < 4. Kaplan–Meier curves confirmed the absence of central lymph nodes as a positive prognostic factor. In the selected cases, Central Neck Dissection (CND) could be avoided even in the presence of positive Lateralcervical Lymph Nodes (LLN+).

Incidence and Risk Factors for Occult Level 3 Lymph Node Metastases in Papillary Thyroid Cancer

BACKGROUND

Papillary thyroid cancer (PTC) frequently disseminates into cervical lymph nodes. Lateral node involvement is described in up to 50 % patients undergoing prophylactic lateral neck dissection. This study aimed to assess this finding and identify which factors predict for occult lateral node disease.

METHODS

Patients with fine needle aspiration-confirmed PTC (Bethesda V or VI), without evidence of cervical lymph node metastases, underwent a total thyroidectomy with prophylactic ipsilateral central and level 3 dissection. Level 3 nodes were removed by compartmental dissection or by sampling the sentinel nodes overlying the jugular vein, according to surgeon preference. Data were collected prospectively from January 2011 to August 2014. Statistical analysis was performed by SPSS software.

RESULTS

A total of 137 patients underwent total thyroidectomy with prophylactic ipsilateral central and level 3 dissection for PTC. The incidence of occult level 3 disease was 30 % (41/137 patients). A total of 48 % of patients (66/137) harbored occult central neck disease. A total of 80.5 % of patients with pN1b disease had macrometastases (≥2 mm), and 15 % exhibited skip metastases with central compartment sparing. In patients with pN1b disease, a median of 6 level 3 nodes were retrieved, with an average involved nodal ratio of 0.29. Multivariate regression demonstrated risk factors for occult lateral neck metastasis include tumor size (odds ratio 1.1), upper pole tumors (odds ratio 6.6), and vascular invasion (odds ratio 3.2) (p < 0.05).

CONCLUSIONS

PTC is associated with a significant incidence of occult central and lateral nodal metastases. In patients undergoing prophylactic central neck dissection, inclusion of level 3 dissection should be considered in patients with large upper lobe cancers.

Recurrence of papillary thyroid carcinoma with lateral cervical node metastases: Predictive factors and operative management

BACKGROUND

Lateral neck lymph node (LN) metastases (N1b) have been identified as independent risk factors of recurrence in patients with papillary thyroid carcinoma (PTC).

OBJECTIVE

This study aimed to determine the predictive factors of recurrence in N1b PTC patients and to clarify the postoperative event patterns.

METHODS

All patients who underwent operation for N1b PTC between 1978 and 2012 were reviewed. The median follow-up period was 6.5 years.

RESULTS

In total, 344 N1b patients were included. Twenty-four patients (7%) were lost to long-term follow-up. Among the remaining 320 patients, the mean (± SD) follow-up time was 8.9 ± 8.8 years (median, 6.5; range, 2-36.4). Eighty-two patients (26%) presented with lymph node recurrence (LR). Multivariate analyses showed that LN metastases with extracapsular extension and the LN ratio (ratio between the number of N1 and number of resected LN) in the lateral compartment were independent predictors of recurrent disease. The median time to reoperation was 19 months (range, 3-173), with 79% of reoperations occurring within 2 years after the initial thyroidectomy. Reoperations for LR (75 patients) were performed in 76% of the patients with a focused minimal access approach or selective LN dissection. After curative reoperative surgery for recurrence, complications occurred in 6 patients (8%), including a 1% permanent complication rate.

CONCLUSION

Extranodal extension of LN metastases and the LN ratio in the lateral compartment are prognostic factors for recurrence. In most cases, reoperation for LR can be performed with a focused minimal access approach, with a low morbidity rate.