Right posterior paratracheal lymph nodes metastasis is one of the predictive factors in right-sided papillary thyroid carcinoma

Construction and validation of a nomogram for predicting cervical lymph node metastasis in tall cell variant of papillary thyroid carcinoma

OBJECTIVE

To analyze the risk factors associated with the occurrence of cervical lymph node metastasis (LNM) in patients with tall cell variant of papillary thyroid carcinoma (TCV-PTC) and to establish a nomogram.

METHODS

Clinical data of 727 patients with TCV-PTC from SEER database were obtained, and they were randomly divided into the training group (n = 508) and validation group (n = 219). The clinicopathological characteristics were analyzed by logistic regression, including age, marital status, race, gender, tumor size(cm), T stage, M stage, bilaterality, capsular invasion, extrathyroidal extension (ETE), vascular invasion and multifocality. The C-index, calibration curves, and DCA were utilized to validate the model from the differentiation and calibration of the nomogram, respectively.

RESULTS

Tumor size, extrathyroidal extension, and multifocality were independent risk factors for the development of LNM in patients with TCV-PTC (P < 0.05). In the training and validation groups, the C-index of internal validation of the nomogram were 0.727 (95% CI: 0.571-0.785) and 0.712 (95%CI: 0.700-0.714). The calibration curves indicated that the model was in good agreement, and the DCA indicated that the nomogram model had good clinical utility.

CONCLUSION

Tumor size, extrathyroidal extension, and multifocality are independent risk factors for developing LNM in TCV-PTC. The nomogram model can predict the risk of developing LNM in TCV-PTC patients and provide clinical guidance.

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.

Pattern and Predictive Factors of Metastasis in Lymph Nodes Posterior to the Right Recurrent Laryngeal Nerve in Papillary Thyroid Carcinoma

OBJECTIVE

The right cervical central lymph nodes include lymph nodes anterior to the right recurrent laryngeal nerve (LN-arRLN) and lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN), and are separated by the right recurrent laryngeal nerve (RLN). LN-prRLN is a common site of nodal recurrence after the resection of papillary thyroid carcinoma (PTC). However, the complexity in anatomical structure brings difficulties in determining the surgical scope, so it is necessary to assess the pattern and predictive factors of right cervical central lymph nodes, especially LN-prRLN metastasis in papillary thyroid carcinoma.

METHODS

A total of 562 diagnosed PTC patients who underwent right or total thyroidectomy were enrolled in this retrospective study. The clinicopathological features were collected, univariate and multivariate analyses were performed to determine predictive factors of the right central lymph node metastasis.

RESULTS

In this study, the metastatic rates of the right CLN, the LN-arRLN and the LN-prRLN were 59.6% (335/562), 51.8% (291/562) and 30.4% (171/562), respectively. And 22.6% (127/562) of patients had both LN-arRLN and LN-prRLN metastasis. Among patients without LN-arRLN metastasis, the rate of LN-prRLN metastasis was 16.2% (44/271), accounting for 25.7% of the LN-prRLN metastasis group. Factors associated with an increased risk of LN-arRLN metastasis include male, age below 55 years, tumor size > 1cm, extrathyroidal extension (ETE), clinical lymph nodes metastasis(cN1), lateral lymph node metastasis, and left CLN metastasis. In addition, ETE, lateral lymph node metastasis, and LN-arRLN metastasis were independent factors of LN-prRLN metastasis. The predictive factors of LN-prRLN in cN0 PTC were further explored, revealing that tumor size ≥1.5cm, ETE, and LN-arRLN metastasis were independent predictors of LN-prRLN metastasis in cN0 PTC.

CONCLUSION

The LN-prRLN should not be ignored in surgery because of its high rate of metastasis. Our findings indicate that thorough dissection of central lymph nodes, especially LN-prRLN is crucial in clinical work.

Endoscopic Left Central Lymph Node Dissection of Thyroid Cancer: Safe, Feasible, and Relatively Easy

Purpose. The purpose of this study was to explore the feasibility of left central lymph node dissection (CLND) in endoscopic thyroidectomy via chest-breast approach (ETCB). Methods. Retrospective analysis of 57 cases of left CLND (group A) via ETCB, 35 cases of open left CLND (group B), and 90 cases of right CLND via ETCB (Group C) were performed from October 2014 to October 2019. Surgical data, complications, and follow-up data were compared among group A and group B, group A and group C, respectively. Results. There were no significant differences between group A and group B in intraoperative blood loss, tumor size, lymph node (LN) metastasis rate, dissected LN number, metastatic LN number, serum thyroglobulin (sTg), radioactive iodine uptake (RAIU), radioactive technetium uptake (RATU), radionuclide imaging of the residual area (RITRA), and radionuclide imaging of suspicious lymph node metastasis (RISLNM). There were no significant differences between group A and group C in age, operation time, intraoperative blood loss, postoperative hospital stay, tumor size, LN metastasis rate, dissected LN number, metastatic LN number, hypoparathyroidism, sTg, RAIU, RATU, RITRA, and RISLNM. There were 5 cases of temporary recurrent laryngeal nerve (RLN) palsy and 1 case of recurrence in group C. Besides, 1 case of lymphatic leakage was in group A. Conclusion. For selected cases, endoscopic left CLND is safe, feasible, efficient, and more easier than endoscopic right CLND.

Unnecessity of Routine Dissection of Right Central Lymph Nodes in cN0 Papillary Thyroid Carcinoma Located at the Left Thyroid Lobe

Objective

The lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) is an important part of the central lymph nodes (LNs). We aimed to explore the rate and predictors of LN-prRLN metastasis in cN0 papillary thyroid carcinoma (PTC) located at the left thyroid lobe.

Methods

Patients with surgically treated primary left lobe PTC were retrospectively enrolled. The metastatic distribution of LN-prRLN and postoperative complications were assessed. The association between LN-prRLN metastasis and clinicopathological variables was evaluated by univariate and multivariate analyses.

Results

A total of 857 patients were included for the analysis. Central LN metastasis was noted in 310 (35.3%) cases. The most (27.6%) and least (1.7%) commonly involved LNs were the left paratracheal LN and the LN-prRLN. In the univariate analysis, the tumor size, multifocality, the extent of extrathyroidal extension (none vs. macroscopic vs. macroscopic maximal), and perineural invasion were associated with positive LN-prRLN. In the multivariate analysis, tumor size of >40.0 mm and macroscopic maximal invasion were found as the only two independent predictors. Transient and permanent hypoparathyroidism were noted in 90 (10.2%) and 13 (1.5%) patients, respectively. Voice change was noted in 40 (4.6%) patients, and 20 patients recovered.

Conclusions

In cN0 PTC located at the left lobe, LN-prRLN metastasis was very uncommon. We found that LN-prRLN dissection is not required routinely, but should be performed if the tumor size is >40.0 mm and macroscopic maximal extrathyroidal extension is present.

Clinical and sonographic features for the preoperative prediction of lymph nodes posterior to the right recurrent laryngeal nerve metastasis in patients with papillary thyroid carcinoma

OBJECTIVE

To evaluate clinical and sonographic features predictive of lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) metastasis in patients diagnosed with papillary thyroid carcinoma (PTC).

METHODS

We retrospectively reviewed the clinical records and ultrasound (US) images of 479 consecutive PTC patients who received total thyroidectomy or right lobectomy with central neck dissection (CND) between October 2017 and October 2019. Univariate and multivariate analyses were performed to identify clinical and sonographic features associated with LN-prRLN metastasis. Receiver operating characteristic (ROC) analysis was applied to evaluate the efficacy of clinical and sonographic features in the preoperative prediction of LN-prRLN metastasis.

RESULTS

Overall, 127 (26.5%) patients had LN-prRLN metastasis. Multivariate logistic regression analysis showed that age < 45 years (p = 0.005; OR 2.155; 95% CI 1.262-3.683), male sex (p = 0.043; OR 1.657; 95% CI 1.016-2.704), tumor diameter > 1 cm (p = 0.042; OR 1.702; 95% CI 1.019-2.842), microcalcifications (p = 0.022; OR 1.980; 95% CI 1.104-3.551), and US-detected lateral compartment lymph node (LLN) metastasis (p = 0.001; OR 2.578; 95% CI 1.500-4.430) were independent risk factors for LN-prRLN metastasis. ROC analysis revealed that the multivariate logistic regression model had good accuracy in predicting LN-prRLN metastasis, with an area under the ROC curve of 0.758.

CONCLUSIONS

Age less than 45 years, male sex, tumor diameter larger than 1 cm, microcalcifications, and US-detected LLN metastasis may preoperatively predict LN-prRLN metastasis.

Cervical lymph nodes, a diagnostic dilemma

Cervical lymph nodes could be a starting sign for a complex diagnosis work-up. Depending on co-morbidities, medical unit and physician's previous experience, the differential diagnosis includes thyroid malignancy, lymphoma, chronic infectious disorders, etc.

Risk factors of metastasis to the lymph nodes posterior to the right recurrent laryngeal nerve in papillary thyroid carcinoma

PURPOSE

To investigate the risk factors of lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) metastasis in papillary thyroid carcinoma.

METHODS

Clinicopathologic feature data of 427 patients with right or double lobes who underwent surgery between January 2014 to August 2019 in the Department of General Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, were retrospectively analyzed. The risk factors of LN-prRLN metastasis were analyzed by the Chi-squared test and multivariate logistic regression.

RESULTS

LN-prRLN metastasis was detected in 96 patients. Univariate analysis showed that age, right-side tumor diameter, capsular invasion, comorbid adenoma, and VIa compartment LN metastasis were significantly associated with LN-prRLN metastasis (all P < 0.05). Multivariate logistic regression analysis showed that right-side tumor diameter, capsular invasion, and VIa compartment LN metastasis were independent risk factors of LN-prRLN metastasis (all P ≤ 0.001). The receiver operating characteristic curve showed that the cutoff value of the right tumor diameter for predicting LN-prRLN metastasis was 1.25 cm (sensitivity = 0.5, specificity = 0.819, area under the curve = 0.720, P < 0.001).

CONCLUSION

The incidence of LN-prRLN metastasis cannot be ignored, and our findings indicate that prophylactic LN-prRLN dissection should be performed in patients with right-side tumor diameter ≥ 1.25 cm, capsular invasion, and VIa compartment LN metastasis.