Correlation between the number of lymph node metastases and lung metastasis in papillary thyroid cancer

Development and validation of a clinical predictive model for high-volume lymph node metastasis of papillary thyroid carcinoma

The central lymph node metastasis (CLNM) status in the cervical region serves as a pivotal determinant for the extent of surgical intervention and prognosis in papillary thyroid carcinoma (PTC). This paper seeks to devise and validate a predictive model based on clinical parameters for the early anticipation of high-volume CLNM (hv-CLNM, > 5 nodes) in high-risk patients. A retrospective analysis of the pathological and clinical data of patients with PTC who underwent surgical treatment at Medical Centers A and B was conducted. The data from Center A was randomly divided into training and validation sets in an 8:2 ratio, with those from Center B serving as the test set. Multifactor logistic regression was harnessed in the training set to select variables and construct a predictive model. The generalization ability of the model was assessed in the validation and test sets. The model was evaluated through the receiver operating characteristic area under the curve (AUC) to predict the efficiency of hv-CLNM. The goodness of fit of the model was examined via the Brier verification technique. The incidence of hv-CLNM in 5897 PTC patients attained 4.8%. The occurrence rates in males and females were 9.4% (128/1365) and 3.4% (156/4532), respectively. Multifactor logistic regression unraveled male gender (OR = 2.17, p < .001), multifocality (OR = 4.06, p < .001), and lesion size (OR = 1.08 per increase of 1 mm, p < .001) as risk factors, while age emerged as a protective factor (OR = 0.95 per an increase of 1 year, p < .001). The model constructed with four predictive variables within the training set exhibited an AUC of 0.847 ([95%CI] 0.815-0.878). In the validation and test sets, the AUCs were 0.831 (0.783-0.879) and 0.845 (0.789-0.901), respectively, with Brier scores of 0.037, 0.041, and 0.056. Subgroup analysis unveiled AUCs for the prediction model in PTC lesion size groups (≤ 10 mm and > 10 mm) as 0.803 (0.757-0.85) and 0.747 (0.709-0.785), age groups (≤ 31 years and > 31 years) as 0.778 (0.720-0.881) and 0.837 (0.806-0.867), multifocal and solitary cases as 0.803 (0.767-0.838) and 0.809 (0.769-0.849), and Hashimoto's thyroiditis (HT) and non-HT cases as 0.845 (0.793-0.897) and 0.845 (0.819-0.871). Male gender, multifocality, and larger lesion size are risk factors for hv-CLNM in PTC patients, whereas age serves as a protective factor. The clinical predictive model developed in this research facilitates the early identification of high-risk patients for hv-CLNM, thereby assisting physicians in more efficacious risk stratification management for PTC patients.

Optimal range of lymph node dissection in patients with unilateral papillary thyroid carcinoma with lateral cervical lymph node metastasis

Background

Whether patients with unilateral papillary thyroid carcinoma (PTC) with lateral cervical lymph node metastasis (LLNM) require prophylactic central regional lymph node dissection (CLND) remains unclear. Herein, we investigated the independent risk factors associated with contralateral central lymph node metastasis (cCLNM) in unilateral PTC with LLNM and analyzed the optimal extent of lymph node dissection by comparing the 5-year recurrence-free survival rates.

Materials and methods

We retrospectively analyzed 695 patients with unilateral papillary thyroid carcinoma and lateral cervical lymph node metastasis. Factors including sex, age, multifocal, location of primary tumor, tumor diameter, capsule invasion, thyroid nodular goiter, Hashimoto thyroiditis, ipsilateral central lymph node metastasis(iCLNM), and lateral cervical lymph node metastasis were analyzed using univariate and multivariate logistic regression analyses to explore the independent risk factors of cCLNM. Propensity scores were matched to compare the 5-year recurrence-free survival rates in patients divided by different lymph node metastases and dissections.

Results

Of all patients who underwent bilateral (b)CLND, 52% (149/286) had cCLNM. Receiver operating characteristic (ROC) curve analysis was performed on 286 patients who underwent bCLND, for which a tumor diameter of 20.5 mm and number of LLNM of 3.5 were used as the thresholds for predicting cCLNM. The 5-year recurrence-free survival (RFS) rates in the cCLN-negative and cCLN-positive groups were 98.6% and 91.2%, with statistically significant differences (P=0.034). The 5-year RFS rates showed no significant difference between the ipsilateral (i)CLND and bCLND groups (P=0.235). Multifactorial regression analysis showed that tumor diameter >2 cm, presence of iCLNM, and number of LLNM >3 were independent risk factors of cCLNM.But male sex, young age (<45 years), multifocality, location of primary tumor, capsule invasion, thyroid nodular goiter, and Hashimoto thyroiditis were not associated with cCLNM.

Conclusion

Not all unilateral PTC with LLNM require prophylactic cCLND; however, prophylactic cCLND is necessary in cases which display high-risk factors for cCLNM, including primary diameter >2 cm, iCLNM, and number of LLNM >3.

Clinical and ultrasonic risk factors for high-volume central lymph node metastasis in cN0 papillary thyroid microcarcinoma: A retrospective study and meta-analysis

OBJECTIVE

Papillary thyroid microcarcinoma (PTMC) comprises more than 50% of all newly detected cases of papillary thyroid carcinoma (PTC). High-volume lymph node metastasis (involving >5 lymph nodes) (hv-LNM) is associated with PTMC recurrence. In half of the clinically node-negative (cN0) PTMC patients, central lymph node metastasis (CLNM) is pathologically present. However, clinical risk factors for high-volume CLNM (hv-CLNM) in cN0 PTMC have not been defined well. Therefore, we aimed to obtain evidence for hv-CLNM risk factors in cN0 PTMC.

DESIGN

Data on patients who visited our hospital between January 2020 and December 2021 were collected; a preoperative diagnosis of cN0 and a postoperative pathological confirmation of PTMC were obtained. After filtering by inclusion versus exclusion criteria, the obtained data (N = 2268) were included in the meta-analysis. Relevant studies published as of 10 April 2022, were identified from the Web of Science, PubMed, WANFANG, and CNKI databases. These eligible studies were included in the meta-analysis and the association between clinicopathological factors and hv-CLNM in cN0 PTMC was assessed. SPSS and MetaXL were used for statistical analyses.

RESULTS

The meta-analysis included 10 previous studies (11,734 patients) and 2268 patients enroled in our hospital for a total of 14,002 subjects. The results of which suggested that younger age (<40, odds ratio [OR] = 3.28, 95% confidence interval [CI] = 2.75-3.92, p < .001 or <45 odds ratio [OR] = 2.93, 95% CI = 2.31-3.72, p < .001), male sex (OR = 2.81, 95% CI = 2.25-3.52, p < .001), tumour size >5 mm (OR = 1.85, 95% CI = 1.39-2.47, p < .001), multifocality (OR = 1.88, 95% CI = 1.56-2.26, p < .001), extrathyroidal extension (OR = 2.58, 95% CI = 2.02-3.30, p < .001), capsule invasion (OR = 2.02, 95% CI = 1.46-2.78, p < .001), microcalcification (OR = 3.25, 95% CI = 2.42-4.36, p < .001) and rich blood flow (OR = 1.65, 95% CI = 1.21-2.25, p = .002) were the significant factors related to an elevated hv-CLNM risk in cN0 PTMC patients. Hashimoto thyroiditis (OR = 0.76, 95% CI = 0.55-1.07, p = .114), irregular margin (versus regular margin, OR = 0.96, 95% CI = 0.68-1.33, p = .787) and hypoechoic (versus nonhypoechoic, OR = 1.27, 95% CI = 0.84-1.92, p = .261) showed no significant association with hv-CLNM.

CONCLUSIONS

Younger age, tumour size >5 mm, males, extrathyroidal extension, multifocality, microcalcification, capsular invasion, and rich blood flow were the significant clinicopathological risk factors for hv-CLNM risk in cN0 PTMC patients. These predictors may compensate for the sensitivity of imaging diagnosis in the preoperative period, thus helping in the effective identification of PTMCs with an invasive phenotype.

[Hemithyroidectomy or total thyroidectomy for low-risk papillary thyroid cancer? : Surgical criteria for primary and secondary choice of treatment in an interdisciplinary treatment concept]

The increase in small intrathyroid papillary thyroid cancer (PTC) observed worldwide over the past two decades, with no increase in cancer-specific mortality, has challenged the previous concept of total thyroidectomy as a one-size-fits-all panacea. After exclusion of papillary microcarcinomas, a systematic review of 20 clinical studies published since 2002, which compared hemithyroidectomy (HT) to total thyroidectomy (TT), found comparable long-term oncological outcomes for low-risk papillary thyroid cancer (LRPTC) 1-4 cm in diameter, whereas postoperative complication rates were markedly lower for HT. To refine individual treatment plans, HT should be combined with ipsilateral central lymph node dissection and intraoperative frozen section analysis for staging. Based on recent evidence from studies and in consideration of individual risk factors, patients with LRPTC can be offered the concept of HT as an alternative to the standard TT. A prerequisite for the treatment selection and decision is a comprehensive patient clarification of the possible advantages and disadvantages of both approaches.

Survival prognostic factors for differentiated thyroid cancer patients with pulmonary metastases: A systematic review and meta-analysis

Background

The prognostic factors for differentiated thyroid cancer (DTC) patients with pulmonary metastases (PM) remain scantly identified and analyzed. Therefore, this systematic review and meta-analysis were performed to identify and summarize the prognostic factors in adult DTC patients with PM to help distinguish patients with different prognoses and inform the rational treatment regimens.

Method

We performed a comprehensive search of the relevant studies published in the Cochrane Library, PubMed, Scopus, Embase, Wanfang database, VIP database, China National Knowledge Infrastructure, and Google Scholar from their inception until February 2021. The pooled hazard ratios (HR) for overall survival and/or progression-free survival (PFS) with 95% confidence intervals were applied to evaluate and identify the potential prognostic factors. Pooled OS at different time points were also calculated for the available data. A random-effects model was used in the meta-analysis.

Results

The review and meta-analysis included 21 studies comprising 2722 DTC patients with PM. The prognostic factors for poor OS were: age over 40 years (HR=7.21, 95% confidence interval [CI] 1.52-34.10, P=0.01, N=788), age over 45 years (HR=2.18, 95% CI 1.26-3.77, P<0.01, N=601), male gender (HR=1.01, 95% CI 1.01-1.19, P=0.03, N=1396), follicular subtype of thyroid cancer (HR=1.63, 95% CI 1.36-1.96, P<0.01, N=2110), iodine non-avidity (HR=3.10, 95% CI 1.79-5.37, P<0.01, N=646), and metastases to other organs (HR=3.18, 95% CI 2.43-4.16, P<0.01, N=1713). Factors associated with poor PFS included age over 45 years (HR=3.85, 95% CI 1.29-11.47, P<0.01, N=306), male gender (HR=1.36, 95% CI 1.06-1.75, P=0.02, N=546), iodine non-avidity (HR=2.93, 95% CI 2.18-3.95, P<0.01, N=395), pulmonary metastatic nodule size over 10mm (HR=2.56, 95% CI 2.02-3.24, P<0.01, N=513), and extra-thyroidal invasion (HR=2.05, 95% CI 1.15-3.67, P=0.02, N=271). The pooled 1, 3, 5, 10, 15, and 20-years OS were 95.24%, 88.46%, 78.36%, 64.86%, 56.57%, and 51.03%, respectively.

Conclusions

This review and meta-analysis identified the prognostic factors of DTC patients with PM. Notably, FTC, metastases to other organs, and iodine non-avidity were particularly associated with poor prognosis. The identified prognostic factors will help guide the clinical management of DTC patients with PM.

Systematic review registration

https://inplasy.com/inplasy-2022-2-0026/, identifier (INPLASY202220026).

Artificial Neural Network-Based Ultrasound Radiomics Can Predict Large-Volume Lymph Node Metastasis in Clinical N0 Papillary Thyroid Carcinoma Patients

Objective

To evaluate the ability of artificial neural network- (ANN-) based ultrasound radiomics to predict large-volume lymph node metastasis (LNM) preoperatively in clinical N0 disease (cN0) papillary thyroid carcinoma (PTC) patients.

Methods

From January 2020 to April 2021, 306 cN0 PTC patients admitted to our hospital were retrospectively reviewed and divided into a training (n = 183) cohort and a validation cohort (n = 123) in a 6 : 4 ratio. Radiomic features quantitatively extracted from ultrasound images were pruned to train one ANN-based radiomic model and three conventional machine learning-based classifiers in the training cohort. Furthermore, an integrated model using ANN was constructed for better prediction. Meanwhile, the prediction of the two models was evaluated in the papillary thyroid microcarcinoma (PTMC) and conventional papillary thyroid cancer (CPTC) subgroups.

Results

The radiomic model showed better discrimination than other classifiers for large-volume LNM in the validation cohort, with an area under the receiver operating characteristic curve (AUROC) of 0.856 and an area under the precision-recall curve (AUPR) of 0.381. The performance of the integrated model was better, with an AUROC of 0.910 and an AUPR of 0.463. According to the calibration curve and decision curve analysis, the radiomic and integrated models had good calibration and clinical usefulness. Moreover, the models had good predictive performance in the PTMC and CPTC subgroups.

Conclusion

ANN-based ultrasound radiomics could be a potential tool to predict large-volume LNM preoperatively in cN0 PTC patients.

Macroscopic extranodal extension is an independent predictor of lung metastasis in papillary thyroid cancer

PURPOSE

Lymph node metastasis is common in patients with papillary thyroid cancer (PTC). Some metastatic lymph nodes may present extranodal extension (ENE). The clinical role of ENE in PTC has yet to be clearly identified. We evaluated macroscopic ENE as a potential prognostic indicator of lung metastasis in PTC.

PATIENTS AND METHODS

We identified 1140 consecutive patients who had PTC initially resected at our cancer center. Clinical data and pathological results were reviewed. Univariate and multivariate logistic regression analyses were used to figure out the association between clinicopathological variables and lung metastasis.

RESULTS

In this cohort, 51.7% of PTC patients had lymph node metastasis; 10.4% had macroscopic ENE positive nodes; 2.3% had lung metastasis. In patients with lymph node metastasis, the average number of positive nodes was 5.10 ± 4.91. Multivariable analysis of clinicopathological factors revealed that extrathyroidal extension (odds ratio [OR], 3.57; 95% CI, 1.41-9.04), macroscopic ENE (OR, 7.08; 95% CI, 2.54-19.74), and number of positive nodes were significantly associated with lung metastasis. Compared with 0-3 positive nodes, 7-9 positive nodes denoted a moderate risk of lung metastasis (OR, 4.53; 95% CI, 1.03-19.85). And 10 positive nodes or more indicated a high risk of lung metastasis (OR, 9.63; 95% CI, 2.65-35.02).

CONCLUSION

Macroscopic ENE could serve as a strong independent prognostic factor of lungmetastasis in PTC. More attention should be paid to patients with ENE positive nodes duringfollow-up.

What Are the Characteristics of Papillary Thyroid Microcarcinoma Prone to High-Volume Lateral Lymph Node Metastasis? - An Analysis of 2981 Consecutive Cases

PURPOSE

To identify candidate factors for predicting high-volume lateral lymph node metastasis (LLNM) in papillary thyroid microcarcinoma (PTMC).

METHODS

We retrospectively studied 2981 patients with PTMC who underwent thyroidectomy from 2013 to 2016. LLNM was identified by histopathology. Patients with different LLNM statuses were compared according to clinical, sonographic and pathological parameters. A multivariate logistic model was established to predict high-volume LLNM (number of metastatic lymph nodes >5).

RESULTS

High-volume LLNM of PTMC was independently associated with age < 40 years (OR = 1.791, P = 0.023), male sex (OR = 2.401, p = 0.001), tumor size > 0.5 cm (OR = 4.839, p < 0.001), extrathyroidal extension (OR = 2.097, p = 0.007) and microcalcification (OR = 2.894, p = 0.002). These five factors were incorporated together to develop a multivariate analysis, which showed good predictive ability (AUC = 0.78, 95% CI 0.72-0.83), with a sensitivity of 80.0% and a specificity of 61.4%. Moreover, more level II or V lateral regions were involved in patients with high-volume LLNM than in those with small-volume LLNM (69.2% vs. 25.0%, p < 0.001; 10.8% vs. 4.7%, p < 0.001).

CONCLUSION

Multilevel LLNM tended to be more common in patients with PTMC who had high-volume LLNM. The high-volume LLNM rates of patients with PTMC with age < 40 years, male sex, tumor size > 0.5 cm, extrathyroidal extension and microcalcification were relatively higher than those without. These findings may be useful for identifying patients at higher high-volume LLNM risk who may require more aggressive treatment or intensive follow-up management.

The differences in distant metastatic patterns and their corresponding survival between thyroid cancer subtypes

INTRODUCTION

This study aimed to systematically elucidate the metastatic patterns and their corresponding survival of each thyroid cancer subtype at time of diagnosis.

METHODS

We accessed the Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2018 to search for primary thyroid cancers with DM at presentation (M1).

RESULTS

We included 2787 M1 thyroid cancers for statistical analyses and the incidence of DM at presentation was 2.4%. Lung was the most common metastatic site for anaplastic thyroid carcinoma (ATC), poorly differentiated thyroid carcinoma (PDTC), papillary thyroid carcinoma (PTC), and oncocytic (Hurthle) cell carcinoma (HCC) whereas bone is the favorable disseminated site of follicular thyroid carcinoma (FTC) and medullary thyroid carcinoma (MTC). Patients with multi-organ metastases had the worst survival whereas bone metastases were associated with a favorable outcome (p < 0.001).

CONCLUSION

There are significant differences in DM patterns of thyroid cancer subtypes and their corresponding survival.

Can Cervical Lymph Node Metastasis Increase the Risk of Distant Metastasis in Papillary Thyroid Carcinoma?

BACKGROUND

Distant metastasis (DM) is a rare event and has a negative effect on the prognosis for papillary thyroid carcinoma (PTC). The relationship between cervical lymph node metastasis and DM is complicated and unclear. This study aimed to evaluate the impact of N stage subclassification on different distant metastasis sites based on age stratification, especially for patients with papillary thyroid microcarcinoma.

METHODS

A total of 28,712 patient with PTC cases between 2010 and 2018 were extracted from the Surveillance, Epidemiology, and End Results database. Multivariable logistic regression analysis was utilized to adjust for confounding variables. Risk stratification, including positive lymph node number and lymph node ratio, was established by receiver operating characteristic curves to help predict DM.

RESULTS

Lung was the most common metastatic site regardless of N0, N1a disease, or N1b disease. As the N stage increased, the higher the rate of DM identified. After age stratification, only N1b disease significantly increased the risk of lung metastasis (LM; odds ratio, OR = 20.45, P < 0.001) rather than bone metastasis (BM; OR = 3.46, P > 0.05) in younger patients. However, in older patients, N1b disease significantly increased the risk of both LM (OR = 4.10, P < 0.001) and BM (OR = 2.65, P = 0.007). In patients with papillary thyroid microcarcinoma (PTMC), N1a disease did not increase the risk of DM, LM, and BM compared with N0 disease (P > 0.05). Furthermore, combined N stage with risk stratification has well performance in predicting DM (area under the curve, AUC = 0.761). Similar results were shown in PTC patients with LM (AUC = 0.770) and BM (AUC = 0.729).

CONCLUSION

Overall, the incidence of DM significantly increased with the progress of N disease after age stratification. N1a disease did not increase the risk of DM in PTMC patients, regardless of LM or BM. Combined N stage with risk stratification may be beneficial for DM prediction.

Development of an Active Surveillance or Surgery Model to Predict Lymph Node Metastasis in cN0 Papillary Thyroid Microcarcinoma

OBJECTIVE

Involvement of multiple lymph node (LN) metastasis in papillary thyroid microcarcinoma (PTMC) may indicate a progressive disease. To assist treatment decision, we conducted a clinical study to develop and validate a prediction model for the preoperative evaluation of LN metastasis involving more than five lymph nodes in patients with clinical N0 (cN0) PTMC.

MATERIAL AND METHODS

Using data from 6,337 patients with cN0 PTMCs at Tianjin Medical University Cancer Institute and Hospital from 2013 to 2017, we identified and integrated risk factors for the prediction of multiple LN metastasis to build a nomogram. The predictive accuracy and discriminative ability of the nomogram were evaluated by the concordance index (C-index) and calibration curve. The model was validated using bootstrap resampling of the training cohort and an independent temporal validation cohort at the same institution.

RESULTS

In the training cohort (n = 3,209 patients), six independent risk factors were identified and included the prediction model (PTMC Active Surveillance or Surgery (ASOS) Model), including age, gender, multifocality, tumor size, calcification, and aspect ratio. The PTMC ASOS model was validated both internally and through the temporal validation cohort (n = 3,128 patients) from the same institute. The C-indexes of the prediction model in the training cohort were 0.768 (95% CI, 0.698-0.838), 0.768 and 0.771 in the internal validation and external validation cohorts, respectively. The area under the receiver operating characteristic curve (AUC) was 0.7068 and 0.6799. The calibration curve for probability of large-LN metastasis showed good agreement between prediction by nomogram and actual observation. DCA curves were used for comparison with another model, and IDI and NRI were also calculated. The cutoff value of our model was obtained by the ROC curve. Based on this model and cut point, a web-based dynamic nomogram was developed (https://tjmuch-thyroid.shinyapps.io/PTMCASOSM/).

CONCLUSION

We established a novel nomogram that can help to distinguish preoperatively cN0 PTMC patients with or without metastasis of multiple lymph nodes. This clinical prediction model may be used in decision making for both active surveillance and surgery.

Related factor analysis for predicting large-volume central cervical lymph node metastasis in papillary thyroid carcinoma

The aim of this study was to investigate the factors related to large-volume central cervical lymph node metastasis (LNM) in papillary thyroid carcinoma. A retrospective study of 340 patients with 642 papillary thyroid carcinoma nodules who underwent thyroidectomy in Peking Union Medical College Hospital between 2011 and 2015 was conducted. These nodules were divided into two groups by the number of central cervical lymph node metastases: large-volume central cervical LNM (>5 metastatic lymph nodes, n = 129) and no central cervical LNM (n = 211). We evaluated the correlations between gender, age, chronic lymphocytic thyroiditis, thyroid ultrasonographic features, and large-volume central cervical LNM. We found that younger age (≤40 years) (OR = 3.796, 95% CI = 2.842, 5.070), male gender (OR = 4.005, 95% CI = 2.858, 5.61), and ultrasonographic features such as tumor macroaxis size (OR = 2.985, 95% CI = 1.581, 5.633), tumor located in the isthmus (OR = 7.578, 95% CI = 4.863, 11.810), ill-defined margin (OR = 3.008, 95% CI = 1.986, 4.556), microcalcification (OR = 2.155, 95% CI = 1.585, 2.929), and abnormal cervical lymph nodes (OR = 13.753, 95% CI = 9.278, 20.385) were independent risk factors for large-volume central cervical LNM in papillary thyroid carcinoma, while chronic lymphocytic thyroiditis (OR = 0.248, 95% CI = 0.172, 0.358) was a protective factor. Younger age (≤40 years), male sex, and ultrasonographic features such as tumor macroaxis size, tumor located in the isthmus, ill-defined margin, microcalcification, and abnormal cervical lymph nodes were independent risk factors for large-volume central cervical LNM in papillary thyroid carcinoma, while chronic lymphocytic thyroiditis can be considered a protective factor. Our results provide a reference for adjusting clinical treatment approaches.

Large-Volume Lateral Lymph Node Metastasis Predicts Worse Prognosis in Papillary Thyroid Carcinoma Patients With N1b

We aimed to evaluate the relevance of large-volume lateral lymph node metastases (LLNMs) at risk of recurrence/persistence in papillary thyroid carcinoma (PTC) with LLNMs (N1b). This retrospective study included 448 PTC patients, who had positive LLNMs confirmed by histology and suspected of LLNMs by preoperative ultrasound. According to the number of pathological LLNMs, patients were divided into large-volume LLNM (number of LLNMs >5) and low-volume LLNM (number of LLNMs ≤5). Risk factors of recurrence/persistence in PTC patients with N1b were analyzed. Preoperative ultrasound features of PTC with large-volume LLNM were analyzed. For the patients with a mean follow-up of 44.0 months, the risk of recurrence/persistence was 25.1% in PTC patients with N1b. The recurrence/persistence rate was significantly higher in patients with large-volume LLNM than in patients with low-volume LLNM by multivariate analysis (37.3% vs. 17.1%; HR = 2.451, 95% CI 1.41-4.261, p = 0.001). The 3-year and 5-year recurrence/persistence-free survival for those with large-volume LLNM were 93.2% and 47.2%, respectively. Moreover, we found that multilevel suspected LLNMs and loss of fatty hilum were independent preoperative indicative factors of large-volume LLNM (OR = 6.239, 95% CI 3.547-10.977, p < 0.001; OR = 5.149, 95% CI 1.859-14.261, p = 0.002). In conclusion, multilevel suspected LLNM and loss of fatty hilum on ultrasound tended to be more common in patients with large-volume LLNM. PTC patients with large-volume LLNM are at a higher recurrent/persistent risk than those with low-volume LLNM. Large-volume LLNM may be used to stratify the risk of recurrence/persistence in PTC.

Predicting large-volume lymph node metastasis in the clinically node-negative papillary thyroid microcarcinoma: a retrospective study

OBJECTIVE

Large-volume lymph node metastasis (LNM) has been believed to be an important predictor for recurrence in papillary thyroid microcarcinoma (PTMC). However, the clinical predictors for large-volume LNM have yet to be established. This study aimed to determine clinical predictors for large-volume LNM in clinically node-negative PTMC.

METHODS

A total of 947 clinically N0 PTMC patients who received total thyroidectomy with lymph node dissection and radioiodine therapy were included. Based on the LNM status, they were divided into two groups: large-volume LNM and small-volume LNM including those patients without LNM. The association between age, gender and other clinical factors and large-volume LNM were investigated. The recurrence-free survival was also compared among these groups.

RESULTS

We found that male gender [odds ratio (OR) = 1.865, P = 0.015], young age (OR = 2.743, P < 0.001) and extrathyroid extension (OR = 5.352, P < 0.001) were independent predictors for high prevalence of large-volume LNM. Young (<40 years) and male patients tended to have large-volume LNM with the highest prevalence of 17.20%, whereas old (≥55 years) and female patients had the lowest prevalence of 2.02%. After median follow-up of 71 months, the recurrence rate was significantly higher for large-volume LNM compared with small-volume LNM (15.48 vs 0.72%, P < 0.05). Large-volume LNM status was significantly associated with decreased recurrence-free probability, while small-volume LNM had little effect on the recurrence-free survival.

CONCLUSIONS

This study showed that in clinically node-negative PTMC, young male patients had a greater incidence of large-volume LNM.

Divergent Metastatic Patterns Between Subtypes of Thyroid Carcinoma Results From the Nationwide Dutch Pathology Registry

BACKGROUND

Metastatic disease is the main cause of cancer-related mortality in thyroid carcinoma (TC) patients. Clinical studies have suggested differences in metastatic patterns between the different subtypes of TC. This study systematically evaluates the metastatic patterns of different subtypes in TC patients.

METHODS

A nationwide review of pathological records of all 650 patients diagnosed with a primary malignancy in the thyroid who underwent an autopsy between 1991 and 2010 was performed. Patients were selected from the Dutch pathology registry (PALGA).

RESULTS

Metastatic disease was present in 228 (35.1%) patients and was found in 38.7%, 17.3%, 75.4%, and 47.8% of patients with follicular, papillary, anaplastic, and medullary types of TC, respectively (P < .0001). The majority of patients had more than 1 metastasis. The most common site of metastatic disease was the lung for papillary (79.7%), follicular (72.9%), and anaplastic (92.1%) carcinoma but not for medullary carcinoma (56.3%), P < .0001. Medullary carcinoma patients most frequently had metastases to the liver (81.3%). The combination of metastases also differed between subtypes.

CONCLUSION

There are major differences in metastatic patterns between different subtypes of TC. The patterns and frequencies identified in this autopsy study may reflect the underlying biology of metastatic thyroid cancer and have potential to influence future monitoring and treatment strategies depending on clinical correlations.

The Number of Central Lymph Nodes on Preoperative Ultrasound Predicts Central Neck Lymph Node Metastasis in Papillary Thyroid Carcinoma: A Prospective Cohort Study

To evaluate the effectiveness of the number of central compartment lymph nodes (CLNs) on ultrasound (US) in predicting CLN metastasis (CLNM). We prospectively studied 309 papillary thyroid cancer (PTC) patients who underwent thyroidectomy with CLN dissection at our center from May 2017 to July 2017. The number and features of CLNs were evaluated preoperatively via US. All US examinations were performed using a Philips iU 22 or a GE Logiq 9 machine. Correlations between CLNs observed via preoperative US and amount of CLNM were evaluated. We found that ≥2 CLNs on the preoperative US was associated with CLNM (P < 0.01). For this feature, the sensitivity, specificity, and area under the curve (AUC) were 54.3%, 66.1%, and 0.61, respectively. The presence of both suspected metastasis and ≥2 CLNs on US had a specificity of 86.5%. In addition, ≥3 CLNs on preoperative US was associated with large-volume CLNM (>5 metastatic CLNs) (P < 0.01). For this feature, the sensitivity, specificity and AUC were 54.8%, 74.5% and 0.65, respectively. The presence of both suspected metastasis and ≥3 CLNs on US had a specificity of 84.9%. The presence of suspected metastasis and/or ≥3 CLNs had a sensitivity of 80.6%. Our results suggest that ≥2 and ≥ 3 CLNs on preoperative US may serve as ancillary preoperative markers for predicting CLNM.

Development and validation of prognostic nomograms for medullary thyroid cancer

Background

This aim of study was to develop and validate clinical nomograms to predict the survival of patients with medullary thyroid cancer.

Patients and methods

Patient data were collected from the Surveillance, Epidemiology, and End Results database between 2004 and 2013. All included patients were randomly assigned into the training and validation sets. Multivariate analysis using Cox proportional hazards regression was performed, and nomograms were constructed. Model performance was evaluated by discrimination and calibration plots.

Results

A total of 1,657 patients were retrospectively analyzed. The multivariate Cox model identified age, tumor size, extrathyroidal extension, N stage, and M stage as independent covariates associated with overall survival (OS) and cancer-specific survival (CSS). Nomograms predicting OS and CSS were constructed based on these covariates. The nomograms predicting both OS and CSS exhibited superior discrimination power to that of TNM staging system in the training and validation sets. Calibration plots indicated that both the nomograms in OS and CSS exhibited high correlation to actual observed results.

Conclusion

The nomograms established in this study provided an alternative tool for prognostic prediction, which may thereby improve individualized assessment of survival risks and lead to the creation of additional clinical therapies.

Metastatic lymph node ratio can further stratify risk for mortality in medullary thyroid cancer patients: A population-based analysis

Medullary thyroid cancer (MTC) has a propensity to cervical lymph node metastases (LNM). Recent studies have shown that both the number of involved lymph nodes (LNs) and the metastatic lymph node ratio (MLNR) confer prognostic information. This study was to determine the predictive value of MLNR on cancer-specific survival (CSS) in SEER (Surveillance, Epidemiology and End Results)-registered MTC patients treated with thyroidectomy and lymphadenectomy between 1991 and 2012, investigate the cutoff points for MLNR in stratifying risk of mortality and provide evidence for selection of appropriate treatment strategies. X-tile program determined 0.5 as optimal cut-off value for MLNR in terms of CSS in 890 MTC patients. According to multivariate Cox regression analysis, MLNR (0.50–1.00) is a significant independent prognostic factor for CSS (hazard ratio 2.161, 95% confidence interval 1.327–3.519, p=0.002). MLNR (0.50–1.00) has a greater prognostic impact on CSS in female, non-Hispanic white, T3/4, N1b and M1 patients. The lymph node yield (LNY) influences the effect of MLNR on CSS; LNY ≥9 results in MLNR (0.50–1.00) having a higher HR for CSS than MLNR (0.00-0.49). In conclusion, higher MLNRs predict poorer survival in MTC patients. Eradication of involved nodes ensures accurate staging and maximizes the ability of MLNR to predict prognosis.

Young Age and Male Sex Are Predictors of Large-Volume Central Neck Lymph Node Metastasis in Clinical N0 Papillary Thyroid Microcarcinomas

BACKGROUND

Large-volume lymph node metastasis (LNM) is associated with poor clinical outcomes in papillary thyroid microcarcinoma (PTMC) patients. However, sensitivity in the detection of central neck LNM on preoperative neck ultrasonography (US) is believed to be low. The aim of this study is to investigate the preoperative clinical factors associated with large-volume LNM in clinical N0 PTMC patients.

METHODS

In all, 2329 clinical N0 PTMC patients who underwent total thyroidectomy with prophylactic central lymph node (LN) dissection were evaluated. The LNM status of these patients was divided into three groups by the number of metastatic nodes: no LNM, small-volume LNM (≤5 metastatic LNs), and large-volume LNM (>5 metastatic LNs). The correlations between age, sex, and other clinical factors and large-volume LNM were evaluated.

RESULTS

Large-volume LNM was found in 94 (4.0%) patients. Young (<40 years old) and male patients tended to have large-volume LNM (p for trend <0.001). Young age (odds ratio [OR] = 2.69 [confidence interval (CI) 1.64-4.32], p < 0.001) and male sex (OR = 5.79 [CI 3.67-9.10], p < 0.001) were independent risk factors for large-volume LNM in multivariate analyses. The prevalence of large-volume LNM ranged from 24% in male patients <40 years of age to only 2% in female patients aged ≥40 years. Multifocal tumors and presence of extrathyroidal extension were also considered risk factors for large-volume LNM.

CONCLUSIONS

Large-volume LNM was more frequently found in young (<40 years) and male patients. These findings support the notion that surgery rather than observation may be favored in young and male clinically LN negative PTMC patients as a primary therapeutic option.

Differentiated and Medullary Thyroid Cancer: Surgical Management of Cervical Lymph Nodes

Thyroid cancer metastasises to the central and lateral compartments of the neck frequently and early. The impact of nodal metastases on outcome is affected by the histological subtype of the primary tumour and the patient's age, as well as the size, number and location of those metastases. The impact of extranodal extension has recently been highlighted as an important prognosticating factor. Although clinically evident nodal disease in the lateral neck compartments has a significant impact on both survival and recurrence, microscopic metastases to the central or the lateral neck in well-differentiated thyroid cancer do not significantly affect outcome. Here we discuss the surgical management of neck metastases in well-differentiated and medullary thyroid carcinoma.

Mediastinal Lymph Node Metastases in Thyroid Cancer: Characteristics, Predictive Factors, and Prognosis

BACKGROUND

Mediastinal lymph node metastases (MLNM) have not been extensively studied. The aim of this study is to investigate the characteristics, predictive factors, and prognosis of MLNM in thyroid cancer.

METHODS

This is a retrospective study based on the thyroid cancer patients with MLNM at our institution from 2008 to 2015.

RESULTS

In total, 73 thyroid cancer patients with positive MLNM were included in this study. It contained sixty patients (82.2%) with papillary thyroid carcinoma (PTC), twelve (16.4%) with medullary thyroid carcinoma, and one (1.4%) with anaplastic thyroid carcinoma. Forty-eight patients had the surgery as initial treatment. Fifty-three (72.6%) patients remained disease-free, and fifteen (20.5%) developed a regional recurrence. Distant metastases occurred in four (5.5%) patients and five (6.8%) patients died. Five-year overall survival rate and disease-free survival (DFS) rate of the PTC patients for initial treatment are 95.4% and 77.2%, respectively. Extrathyroidal extension and multiple lymph nodes involved were associated with DFS in PTC patients.

CONCLUSIONS

Initial therapeutic control is very important for the thyroid cancer patients. Extrathyroidal extension and multiple mediastinal lymph nodes involved were the influence factors of prognosis in the thyroid cancer patients with MLNM.

Risk factors for recurrence in patients with papillary thyroid carcinoma undergoing modified radical neck dissection

BACKGROUND

This study evaluated the impact of lymph node-related factors on the risk of and site of recurrence in patients who had papillary thyroid carcinoma with lymph node metastasis in the lateral compartment (classified as pN1b).

METHODS

Patients underwent total thyroidectomy with unilateral modified radical neck dissection for classical papillary thyroid carcinoma. Risk factors for recurrence were evaluated according to the pattern of recurrence.

RESULTS

A total of 324 patients were included in the study. The median follow-up was 63 (range 14-181) months. Recurrence was detected in 47 patients (14·5 per cent). In the multivariable analysis, a maximum diameter of metastatic lymph nodes larger than 2·0 cm (hazard ratio (HR) 1·15, 95 per cent c.i. 1·06 to 1·25; P = 0·033) and a central compartment metastatic lymph node ratio of more than 0·42 (HR 3·35, 1·65 to 6·79; P < 0·001) were identified as independent risk factors for locoregional recurrence. Age 45 years or older (HR 5·69, 1·24 to 26·12; P = 0·025) and extranodal extension of metastasis (HR 12·71, 1·64 to 98·25; P = 0·015) were risk factors for distant metastasis. In subgroup analysis of locoregional recurrence, several lymph node-related factors affected the risk of recurrence according to the specific site of metastasis.

CONCLUSION

Lymph node-related factors are of importance for the risk of recurrence in patients with classical papillary thyroid carcinoma classified as pN1b.

Optimal Cut-Off Values of Lymph Node Ratio Predicting Recurrence in Papillary Thyroid Cancer

Regional lymph node (LN) metastasis has a significant impact for prediction of recurrence in patients with papillary thyroid cancers (PTC); however, the prognostic value of the lymph node ratio (LNR), which is defined as the ratio of the number of metastatic LNs to the total number of investigated LNs, is controversial. In this study, we determined the optimal cut-off values of LNRs for the prediction of recurrence in PTC patients.This large cohort study retrospectively evaluated 2294 patients who had undergone total thyroidectomy for PTC at a single institution from October 1985 to June 2009. The prediction probability of central LNR (cLNR, level VI) and total LNR (tLNR, levels II-VI) were estimated by binominal logistic regression analysis. Hazard ratios of the cut-off LNR values for cancer recurrence were calculated for relevant covariates using multivariate Cox regression analyses. Kaplan-Meier analyses were also utilized to assess the effects of estimated LNR cut-off values on recurrence-free survival (RFS).Of the 2294 patients, 138 (6.0%) presented cancer recurrence during the follow-up period (median duration = 107.1 months). The prediction probability indicated that LNRs of 0.4 and 0.5 for central LN and total LN, respectively, are optimal cut-off values for precise prediction with minimization of outliers. Multivariate Cox regression analyses revealed that cLNR ≥0.4 was independently predictive of recurrence in patients with N0 and N1a PTCs (hazard ratio [HR]: 7.016, 95% confidence interval [CI]: 3.72-12.986, P < 0.001) and that tLNR ≥0.5 indicated a significantly increased risk of recurrence in patients with N1b PTCs (HR: 2.372, 95% CI: 1.458-3.860, P < 0.001). In addition, Kaplan-Meier analyses clearly demonstrated that these LNR cut-off values are precisely operational in RFS estimation.The cut-off LNR values of 0.4 and 0.5 for cLNR and tLNR, respectively, were identified. Risk stratification combined with these LNR cut-off values may prove useful to determine treatment and follow-up strategies for PTC patients.

Follicular cell-derived thyroid cancer

Follicular cell-derived thyroid cancers are derived from the follicular cells in the thyroid gland, which secrete the iodine-containing thyroid hormones. Follicular cell-derived thyroid cancers can be classified into papillary thyroid cancer (80-85%), follicular thyroid cancer (10-15%), poorly differentiated thyroid cancer (<2%) and undifferentiated (anaplastic) thyroid cancer (<2%), and these have an excellent prognosis with the exception of undifferentiated thyroid cancer. The advent and expansion of advanced diagnostic techniques has driven and continues to drive the epidemic of occult papillary thyroid cancer, owing to overdiagnosis of clinically irrelevant nodules. This transformation of the thyroid cancer landscape at molecular and clinical levels calls for the modification of management strategies towards personalized medicine based on individual risk assessment to deliver the most effective but least aggressive treatment. In thyroid cancer surgery, for instance, injuries to structures outside the thyroid gland, such as the recurrent laryngeal nerve in 2-5% of surgeries or the parathyroid glands in 5-10% of surgeries, negatively affect quality of life more than loss of the expendable thyroid gland. Furthermore, the risks associated with radioiodine ablation may outweigh the risks of persistent or recurrent disease and disease-specific mortality. Improvement in the health-related quality of life of survivors of follicular cell-derived thyroid cancer, which is decreased despite the generally favourable outcome, hinges on early tumour detection and minimization of treatment-related sequelae. Future opportunities include more widespread adoption of molecular and clinical risk stratification and identification of actionable targets for individualized therapies.

Sub-Classification of Lateral Cervical Lymph Node Metastasis in Papillary Thyroid Carcinoma by Pathologic Criteria

Background

Lateral cervical lymph node (LCLN) metastasis, or pathologic N1b disease, is an important risk factor in papillary thyroid carcinoma (PTC). However, many patients have favorable prognosis even with pathologic N1b patients in clinical practice. The study aims to identify high- and intermediate-risk groups based on initial pathologic characteristics in these patients.

Patients

This study included 518 classical PTC patients confirmed as pathologic N1b at initial surgery between 2001 and 2010. All patients underwent a single fixed activity (5.6 GBq) of radioactive I-131 remnant ablation.

Results

Patients with a primary tumor larger than 4 cm, gross extrathyroidal extension, metastatic LN larger than 3 cm, or greater than 10 metastatic LCLN were classified as high-risk group. These comprehensive pathologic criteria were retrieved from cox proportional hazard models. Twenty two percent of patients (n = 113) were classified as high-risk and 78% (n = 405) as intermediate-risk group. Successful ablation was identified in only 32% of the patients in the high-risk group and 61% in the intermediate-risk group (p < 0.001). The difference between the two risk groups was independent to gender. There was a significant difference in disease-free survival between the high- and intermediate- risk N1b groups during 5.1 years of median follow-up (84% vs. 59%, p < 0.001). Distant metastasis was more prevalent in the high-risk group (20%) than in the intermediate-risk group (4%, p < 0.001).

Conclusions

The prognosis of PTC patients with LCLN metastasis varies depending on initial pathologic characteristics. We proposed the comprehensive pathologic criteria for sub-classification of N1b into high- and intermediate-risk groups and this sub-classification may permit personalized management of N1b PTC patients.

Intratumor heterogeneity and clonal evolution in an aggressive papillary thyroid cancer and matched metastases

The contribution of intratumor heterogeneity to thyroid metastatic cancers is still unknown. The clonal relationships between the primary thyroid tumors and lymph nodes (LN) or distant metastases are also poorly understood. The objective of this study was to determine the phylogenetic relationships between matched primary thyroid tumors and metastases. We searched for non-synonymous single-nucleotide variants (nsSNVs), gene fusions, alternative transcripts, and loss of heterozygosity (LOH) by paired-end massively parallel sequencing of cDNA (RNA-Seq) in a patient diagnosed with an aggressive papillary thyroid cancer (PTC). Seven tumor samples from a stage IVc PTC patient were analyzed by RNA-Seq: two areas from the primary tumor, four areas from two LN metastases, and one area from a pleural metastasis (PLM). A large panel of other thyroid tumors was used for Sanger sequencing screening. We identified seven new nsSNVs. Some of these were early events clonally present in both the primary PTC and the three matched metastases. Other nsSNVs were private to the primary tumor, the LN metastases and/or the PLM. Three new gene fusions were identified. A novel cancer-specific KAZN alternative transcript was detected in this aggressive PTC and in dozens of additional thyroid tumors. The PLM harbored an exclusive whole-chromosome 19 LOH. We have presented the first, to our knowledge, deep sequencing study comparing the mutational spectra in a PTC and both LN and distant metastases. This study has yielded novel findings concerning intra-tumor heterogeneity, clonal evolution and metastases dissemination in thyroid cancer.

Prognostic value of microscopic lymph node involvement in patients with papillary thyroid cancer

CONTEXT

The impact of microscopic nodal involvement on the risk of persistent/recurrent disease (PRD) remains controversial in patients with papillary thyroid carcinoma (PTC).

OBJECTIVE

The goal of the study was to assess the risk of PRD and the 4-year outcome in PTC patients according to their initial nodal status [pNx, pN0, pN1 microscopic (cN0/pN1) or pN1 macroscopic (cN1/pN1)].

DESIGN

We conducted a retrospective cohort study.

PATIENTS

The study included 305 consecutive PTC patients referred for radioiodine ablation from 2006 to 2011.

MAIN OUTCOME MEASURE

We evaluated the risk of structural PRD and the disease status at the last follow-up. At ablation, persistent disease was consistently assessed by using post-radioiodine ablation scintigraphy combining total body scan and neck and thorax single-photon computed tomography-computed tomography (SPECT-CT) acquisition.

RESULTS

Of 305 patients, 128 (42%) were pNx, 84 (28%) pN0, 44 (14%) pN1 microscopic, and 49 (16%) pN1 macroscopic. The 4-year cumulative risk of PRD was higher in pN1 macroscopic than in pN1 microscopic patients (49% vs 24%, P = .03), and higher in pN1 microscopic than in pN0 (12%, P = .01) or pNx patients (6%, P < .001). On multivariate analysis, tumor size of 20 mm or greater [relative risk (RR) 3.4; P = .0001], extrathyroid extension (RR 2.6; P < .003), pN1 macroscopic (RR 4.5; P < .0001), and pN1 microscopic (RR 2.5; P < .02) were independent risk factors for PRD. At the last visit, the proportion of patients with no evidence of disease decreased from pNx (98%), pN0 (93%), and pN1 microscopic (89%) to pN1 macroscopic patients (70%) (P < .0001, Cochran-Armitage trend test). Extrathyroid extension (odds ratio 9.7; P < .0001) and N1 macroscopic (OR 4.9; P < .001) independently predicted persistent disease at the last visit, but N1 microscopic did not.

CONCLUSIONS

PATIENTS with microscopic lymph node involvement present an intermediate outcome between that observed in pN0-pNx patients and pN1 macroscopic patients. These data may justify modifications to the risk recurrence staging systems.

[Total thyroidectomy with lymph node dissection of the central compartment for node-positive, capsular invasive papillary thyroid cancer: video contribution]

The aim of radical oncological surgery for nodal metastasized papillary thyroid cancer is, as for other oncological interventions in visceral surgery, the anatomy-related implementation of the concept of en bloc (no touch) resection of the organ bearing the primary tumor together with the first lymph node station, while the structures of the aerodigestive tract, the recurrent laryngeal nerves and parathyroid glands are preserved. The surgical technique is demonstrated in detail with the help of a video of the operation and which is available on-line, the advantages and disadvantages of the technique are discussed.

Differentiating the location of cervical lymph node metastasis is very useful for estimating the risk of distant metastases in papillary thyroid carcinoma

OBJECTIVE

A larger primary tumour size, greater numbers of cervical lymph node (LN) metastasis are associated with a higher risk of distant metastases in papillary thyroid carcinoma (PTC). However, the impact of the location of cervical LN metastasis on distant metastasis is controversial. The aim of this study was to evaluate the risk of distant metastases according to the tumour size and LN status in PTC patients, with special consideration of the LN metastasis pattern.

PATIENTS

This retrospective cohort study reviewed 1700 classical PTC patients who underwent initial thyroid surgery at Asan Medical Center between 2000 and 2004.

RESULTS

The cumulative risk of distant metastases was increased with the increase in tumour size and was significantly different according to the location of involved LNs by the tumour node metastasis (TNM) staging. The cumulative risk in pN1b group showed the steepest increasing pattern with the increase in tumour size compared with pN1a and pN0/Nx group. When we analysed the cumulative risk of distant metastases according to the number of involved LNs, patients with more than 20 involved LNs also had the steepest increase in the risk of distant metastases with the increase in tumour size. However, only the location of involved LNs, not the number of involved LNs, was associated with distant metastases in multivariate analysis.

CONCLUSIONS

We confirm that the location of involved LNs categories based on the TNM staging system is more useful than the number of involved LNs categories for estimating the risk of distant metastasis in PTC. Differentiating N1a disease from N1b disease is important for the follow-up and management of patients with PTC.

Current status and future perspectives in differentiated thyroid cancer

Thyroid cancer is increasing all over the world. The exact cause of this increase is still debated and there are conflicting reports. Sophisticated molecular studies suggest that environmental chemicals may have effects of thyroid carcinogenesis. The development of powerful molecular biology techniques has enabled targeted next-generation sequencing for detection of mutations in thyroid cancer, and this technique can make a specific diagnosis of thyroid cancer in cytologically indeterminate cases. The initial treatment of well-differentiated thyroid cancer (DTC) is surgery followed by radioiodine remnant ablation. However, further studies are needed to determine the optimal dosage of radioactive iodine for DTC patients with lateral neck metastasis. DTC is an indolent tumor and may cause death even decades later. Thus, long-term follow-up is mandatory. Recently, dynamic risk stratification (DRS) has begun to use stimulated thyroglobulin level at 1 year after the initial treatment and restratified the risk in accordance with the response to the initial treatment. This DRS strategy accurately predicts disease free survival and can be widely used in daily clinical settings. For the iodine refractory metastatic disease, redifferentiation therapy and targeted therapy are two promising alternative treatments. Sorafenib is the first approved agent for the treatment of progressive iodine refractory advanced thyroid cancer in Korea and may be very helpful for radioactive-refractory locally advanced or metastatic DTC. Selumetinib may be an effective redifferentiating agent and could be used within several years.

German Association of Endocrine Surgeons practice guideline for the surgical management of malignant thyroid tumors

INTRODUCTION

Over the past years, the incidence of thyroid cancer has surged not only in Germany but also in other countries of the Western hemisphere. This surge was first and foremost due to an increase of prognostically favorable ("low risk") papillary thyroid microcarcinomas, for which limited surgical procedures are often sufficient without loss of oncological benefit. These developments called for an update of the previous practice guideline to detail the surgical treatment options that are available for the various disease entities and tumor stages.

METHODS

The present German Association of Endocrine Surgeons practice guideline was developed on the basis of clinical evidence considering current national and international treatment recommendations through a formal expert consensus process in collaboration with the German Societies of General and Visceral Surgery, Endocrinology, Nuclear Medicine, Pathology, Radiooncology, Oncological Hematology, and a German thyroid cancer patient support organization.

RESULTS

The practice guideline for the surgical management of malignant thyroid tumors includes recommendations regarding preoperative workup; classification of locoregional nodes and terminology of surgical procedures; frequency, clinical, and histopathological features of occult and clinically apparent papillary, follicular, poorly differentiated, undifferentiated, and sporadic and hereditary medullary thyroid cancers, thyroid lymphoma and thyroid metastases from primaries outside the thyroid gland; extent of thyroidectomy; extent of lymph node dissection; aerodigestive tract resection; postoperative follow-up and surgery for recurrence and distant metastases.

CONCLUSION

These evidence-based recommendations for surgical therapy reflect various "treatment corridors" that are best discussed within multidisciplinary teams and the patient considering tumor type, stage, progression, and inherent surgical risk.