Clinical implications of bilateral lateral cervical lymph node metastasis in papillary thyroid cancer: a risk factor for lung metastasis

A retrospective study of factors affecting contralateral central-neck lymph node metastasis in unilateral papillary thyroid carcinoma

BACKGROUND

In 30-40% of papillary thyroid cancer patients, central neck lymph node metastasis occurs. As a result, prophylactic central neck lymph node dissection is performed. The extent of lymph node dissection and prophylactic central neck lymph node dissection is still debatable. The incidence of central neck lymph node metastasis and related factors were investigated in this study, and also the necessity of both central neck lymph node dissections.

METHODS

Between December 2017 and December 2019, 482 patients had thyroidectomy at Pusan National University Yangsan Hospital. A retrospective study of 186 patients who had a thyroidectomy with bilateral central neck lymph node dissection for unilateral thyroid carcinoma was done.

RESULTS

Ipsilateral and contralateral central neck lymph node metastasis were identified in 40.9% (76/186) and 19.3% (36/186), respectively. Male (p < 0.001), tumor size >1 cm (p = 0.047), extrathyroidal extension (p = 0.002), central neck lymph node metastases >5 (p < 0.001), lateral neck lymph node metastasis (p = 0.012), and ipsilateral central neck lymph node metastasis (p < 0.001) were associated with the contralateral central neck lymph node metastasis in univariate analysis. In a multivariate analysis, extrathyroidal extension (OR, 3.664), more than 5 central neck lymph node metastases (OR, 29.667), ipsilateral central neck lymph node metastasis (OR, 3.911), and male (OR, 5.890) were related to contralateral central neck lymph node metastasis.

CONCLUSION

Male, extrathyroidal extension, and ipsilateral central neck lymph node metastasis may be considered for contralateral prophylactic central neck lymph node dissection. In the future, it is thought that more research on the recurrence rate will be required.

Lung metastasis from thyroid cancer: A case report of unusual imaging presentation of lung metastases

RATIONALE

Thyroid cancer (TC) is the most common malignancy of the head and neck and endocrine system. Distant metastases from TC are rare and are diagnosed in only 1% to 4% of patients, and these patients have a poor prognosis, which is the leading cause of TC-related deaths. There are few reports on metastatic TC in China and abroad, and even fewer reports on lung metastases from TC. We report a special patient with lung metastases of TC.

PATIENT CONCERNS

The patient is a 31-year-old female who was found to have both lung nodules during physical examination. Chest computed tomography (CT) showed that the density of both lung nodules was the same as the vascular density, considering that the possibility of vascular origin was not excluded.

DIAGNOSIS

After consultation with the whole hospital, it was considered that vascular malformations, hemangiomas, and malignant metastases were not excluded, the patient percutaneous lung biopsy had a high risk of bleeding, and thoracoscopic lobectomy could be performed in thoracic surgery to further clarify the pathology and diagnosis.

OUTCOMES

The patient underwent thoracoscopic left lower lobe wedge resection on February 24, 2021. Postoperative pathology: (left lower lung mass) metastatic carcinoma, combined with morphology and immunohistochemistry, leaning toward thyroid follicular carcinoma lung metastasis. On May 27, 2021, the patient underwent "total thyroidectomy + lymph node dissection in the right cervical VI region." Pathological examination: (right lobe and isthmus of the thyroid gland) papillary TC, follicular subtype, and classic type, with interstitial fibrosis. The patient was diagnosed with lung metastasis of TC.

LESSONS

This patient had the same CT value of lung metastases as the vascular CT value, which is relatively rare in our clinical practice and worthy of our study. The special CT imaging presentation of this TC patient with lung metastases further broadened our horizon. In clinical practice, when we encounter similar cases, we should combine more with other tests and examinations of patients to avoid misdiagnosis and missed diagnosis.

Case Report: A papillary thyroid microcarcinoma patient with skip lymph node metastasis and multiple distant metastasis

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer. Papillary thyroid microcarcinoma (PTMC) is defined as PTC with a diameter less than 1 centimeter. Most lymph nodes of PTC patients have metastasized to the central neck, and a few lymph nodes have metastasized to the lateral neck. Skip lymph node metastasis, that is, lateral cervical lymph node metastasis without central lymph node metastasis, is even less common. Additionally, distant metastasis of PTMC is also rare, mainly occurring in the lung and bone. Here, we reported a case of PTMC patient with skip lymph node metastasis and multiple distant metastasis. The patient presented with a huge shoulder mass and the primary tumor was found to originate from the thyroid. However, the patient only suffered with PTMC via postoperative pathological results, and interestingly, the patient only had skip lymph node metastasis. Thus, we should focus on PTMC patients with lateral cervical lymph nodes metastasis, especially those with skip metastasis. In addition, this case provides a new perspective for us to understand of skip lymph metastasis and distant metastasis of PTMC.

Nomogram individually predicts the risk for distant metastasis and prognosis value in female differentiated thyroid cancer patients: A SEER-based study

Objective

Distant metastasis (DM) is an important prognostic factor in differentiated thyroid cancer (DTC) and determines the course of treatment. This study aimed to establish a predictive nomogram model that could individually estimate the risk of DM and analyze the prognosis of female DTC patients (FDTCs).

Materials and methods

A total of 26,998 FDTCs were retrospectively searched from the Surveillance, Epidemiology, and End Results (SEER) database from 2010 to 2018 and randomly divided into validation and training cohorts. Univariate and multivariate analyses were performed to screen for prognostic factors and construct a prediction nomogram. The performance of the nomogram was assessed by the area under the receiver operating characteristic curve (AUC), concordance index (C-index), and a calibration curve. The overall survival (OS) and cancer-specific survival (CSS) were evaluated by Kaplan–Meier (K-M) analysis.

Results

A total of 263 (0.97%) FDTCs were reported to have DM. K-M analysis showed the association of multiple-organ metastases and brain involvement with lower survival rates (P &lt; 0.001) in patients. Tumor size, age at diagnosis, thyroidectomy, N1 stage, T3–4 stage, and pathological type were independent predictive factors of DM in FDTCs (all P &lt; 0.001). Similarly, age at diagnosis, Black, DM, T3–4 stage, thyroidectomy, and lung metastasis were determined as independent prognostic factors for FDTCs (all P &lt; 0.001). Several predictive nomograms were established based on the above factors. The C-index, AUC, and calibration curves demonstrated a good performance of these nomogram models.

Conclusion

Our study was successful in establishing and validating nomograms that could predict DM, as well as CSS and OS in individual patients with FDTC based on a large study cohort. These nomograms could enable surgeons to perform individualized survival evaluation and risk stratification for FDTCs.

Pan-cancer analysis of the prevalence and associated factors of lung metastasis and the construction of the lung metastatic classification system

This study first presents an analysis of the prevalence and associated factors of the lung metastasis (LM) database and then uses this analysis to construct an LM classification system. Using cancer patient data gathered from the surveillance, epidemiology, and end results (SEER) database, this study shows that the prevalence of LM is not consistent among different cancers; that is, the prevalence of LM ranges from 0.0013 [brain; 95% confidence interval (95% CI); 0.0010–0.0018] to 0.234 (“other digestive organs”; 95% CI; 0.221–0.249). This study finds that advanced age, poor grade, higher tumor or node stage, and metastases including bone, brain, and liver are positively related to LM occurrence, while female gender, income, marital status, and insured status are negatively related. Then, this study generates four categories from 58 cancer types based on prevalence and influence factors and satisfactorily validates these. This classification system reflects the LM risk of different cancers. It can guide individualized treatment and the management of these synchronous metastatic cancer patients and help clinicians better distribute medical resources.

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.

Prediction of lung metastases in thyroid cancer using machine learning based on SEER database

PURPOSE

Lung metastasis (LM) is one of the most frequent distant metastases of thyroid cancer (TC). This study aimed to develop a machine learning algorithm model to predict lung metastasis of thyroid cancer for providing relative information in clinical decision-making.

METHODS

Data comprising of demographic and clinicopathological characteristics of patients with thyroid cancer were extracted from the National Institutes of Health (NIH)'s Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015, which is employed to develop six machine learning algorithm models support vector machine (SVM), logistic regression (LR), eXtreme gradient boosting (XGBoost), decision tree (DT), random forest (RF), and k-nearest neighbor (KNN). Compared and evaluated models by the following indicators: accuracy, precision, recall rate, F1-score, the area under the ROC curve (AUC) value and Brier score, and interpreted the association between clinicopathological characteristics and target variables based on the best model.

RESULTS

Nine thousand nine hundred and fifty patients were selected, which including 212 patients (2.1%) with lung metastasis, and 9738 patients without lung metastasis (97.9%). Multivariate logistic regression showed that age, T stage, N stage, and histological type were independent factors in TC with LM. Evaluation indicators of the best model- RF were as following: accuracy (0.99), recall rate (0.88), precision (0.61), F1-score (0.72), AUC value (0.99), and the Brier score (0.016).

CONCLUSION

RF learning model performed better and can be applied to forecast lung metastasis of thyroid cancer, and offer valuable and significant reference for clinicians' decision-making in advance.

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.

Predictive Impact of Metastatic Lymph Node Burden on Distant Metastasis Across Papillary Thyroid Cancer Variants

Background: While numerous factors determine prognosis in papillary thyroid carcinoma (PTC), distant metastasis (M1) represents one of the most dire. Escalating nodal burden and aggressive histology may contribute to higher metastatic risk, but this relationship is poorly defined and challenging to anticipate. We evaluate the predictive impact of these histological features on predicting distant metastases at initial presentation. Methods: Univariate and multivariable logistic regression models of conventional and aggressive thyroid cancer variants (well-differentiated papillary thyroid carcinoma [WDPTC], diffuse sclerosing variant [DSV], tall cell variant [TCV], poorly differentiated thyroid cancer [PDTC], and anaplastic thyroid carcinoma [ATC]) identified via U.S. cancer registry data were constructed to determine associations between M1 status and quantitative nodal burden. Associations between metastatic lymph node (LN) number and M1 disease were modeled using univariate and multivariable logistic regression with interaction terms, as well as a linear continuous probability model. Results: Overall, M1 prevalence at disease presentation was 3.6% (n = 1717). When stratified by subtype, M1 prevalence varied significantly by histology (WDPTC [1.0%], DSV [2.3%], TCV [4.1%], PDTC [17.4%], ATC [38.4%] [p < 0.001]). For WDPTC, M1 prevalence escalated with metastatic LN number (0 LN+ [0.5%], 1-5 LN+ [2.0%], 6-10 LN+ [3.4%], >10 LN+ [5.5%] [p < 0.001]) and LN ratio (p < 0.001). A statistically significant interaction was observed between histology and increasing nodal burden for M1 risk. On multivariable analysis, each successive metastatic LN conferred increased M1 risk for WDPTC (odds ratio [OR] 1.06 [1.05-1.08], p < 0.001) and TCVs (OR 1.04 [1.02-1.07], p < 0.001). In contrast, other aggressive variants had a higher baseline M1 risk, but this did not vary based on the number of positive LN (DSV, OR 1.02 [0.95-1.10], p = 0.52; PDTC, OR 1.00 [0.98-1.02], p = 0.66; ATC, 1.00 [0.98-1.02], p = 0.97). Conclusions: Progressive nodal burden independently escalates the risk of distant metastasis in WDPTC and TCVs of PTC. Conversely, aggressive variants such as PDTC and ATC have substantial M1 risk at baseline and appear to be minimally affected by metastatic nodal burden. Consideration of these factors after surgery may help tailor clinical decision-making for treatment and surveillance. Further studies are warranted to calibrate the ideal management approach for these higher risk patient groups.

Loss of ZNF677 Expression Is an Independent Predictor for Distant Metastasis in Middle Eastern Papillary Thyroid Carcinoma Patients

Thyroid cancer incidence has increased in recent decades. Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer. Approximately 30% of PTC patients develop recurrence or distant metastasis and tend to have poor prognosis. Therefore, the identification of targetable biomarkers in this subset of patients is of great importance. Accumulating evidence indicates that zinc finger protein 677 (ZNF677), which belongs to the zinc finger protein family, is an important effector during the progression of multiple malignancies. However, its role in Middle Eastern PTC patients has not been fully illustrated. Here, we uncovered the molecular mechanism and the clinical impact of ZNF677 expression in a large cohort of more than 1200 Middle Eastern PTC and 15 metastatic tissues. We demonstrated that ZNF677 is frequently downregulated in primary PTC (13.6%, 168/1235) and showed that complete loss of expression of ZNF677 is significantly associated with aggressive clinico-pathological markers such as extrathyroidal extension (p = 0.0008) and distant metastases (p < 0.0001). We also found a significantly higher incidence of ZNF677 loss in primary tumors with distant metastases (33.3%; p < 0.0001) as well as in distant metastatic tissues (46.7%; p = 0.0002) compared to the overall cohort (13.6%). More importantly, PTC with loss of ZNF677 expression showed significantly lower metastasis-free survival (p = 0.0090). Interestingly, on multivariate logistic regression analysis, ZNF677 loss was an independent predictor of distant metastasis in PTC (Odds ratio = 2.60, 95% Confidence interval = 1.20–5.62, p = 0.0155). In addition, we found a significant association between ZNF677 loss and phospho-AKT expression (p < 0.0001). Our functional molecular results suggest that ZNF677 acts as a tumor suppressor, mediating its effect by inhibiting AKT phosphorylation. Taken together, our results highlight the pivotal role played by ZNF677 during carcinogenesis and metastasis formation in Middle Eastern PTC patients.

LncRNA-HCG18 regulates the viability, apoptosis, migration, invasion and epithelial-mesenchymal transition of papillary thyroid cancer cells via regulating the miR-106a-5p/PPP2R2A axis

The incidence of papillary thyroid cancer (PTC) has experienced a rapid increase in recent years. Long non-coding RNA-homo sapiens HLA complex group (HCG) 18 plays a regulatory role in cancers, but its role in PTC remained unknown. This study determined the expressions of HCG18, microRNA (miR)-106a-5p, and protein phosphatase 2 regulatory subunit B alpha (PPP2R2A) in PTC tissues and cells by qRT-PCR. ENCORI predicted the targeting relation between HCG18 and miR-106a-5p. TargetScan v7.2 predicted the targeting relation between miR-106a-5p and PPP2R2A. Dual-luciferase reporter assay was performed to validate the two targeting relations. The viability, migration, and invasion of PTC cells were detected by Cell Counting Kit-8, wound healing assay, and Transwell assay, respectively. The expressions of matrix metalloproteinase 2 (MMP-2), MMP-9, E-cadherin, N-cadherin, and Vimentin in TPC-1 and MDA-T68 cells were assessed by qRT-PCR and Western blot. It was found that HCG18 was down-regulated in PTC. Overexpressing HCG18 suppressed viability, migration, and invasion, promoted apoptosis, and inhibited miR-106a-5p expression in PTC cells. HCG18 interacted with miR-106a-5p, the expression of which was upregulated in PTC. Upregulating miR-106a-5p expression by lentivirus infection promoted viability, migration and invasion and inhibited apoptosis of PTC cells, reversed the effect of HCG18 on the biological behaviors of PTC cells, and promoted the expressions of MMP-2, MMP-9, E-cadherin, and Vimentin and downregulated E-cadherin expression in PTC cells. PPP2R2A, a direct target of miR-106a-5p, was downregulated in PTC, and HCG18 promoted PPP2R2A expression in PTC cells by sponging miR-106a-5p. Furthermore, PPP2R2A reversed the effects of miR-106a-5p on PTC cells. In conclusion, HCG18 suppressed viability, migration, invasion and epithelial-mesenchymal transition and promoted apoptosis of PTC cells via regulating the miR-106a-5p/PPP2R2A axis.

2020 Imaging Guidelines for Thyroid Nodules and Differentiated Thyroid Cancer: Korean Society of Thyroid Radiology

Imaging plays a key role in the diagnosis and characterization of thyroid diseases, and the information provided by imaging studies is essential for management planning. A referral guideline for imaging studies may help physicians make reasonable decisions and minimize the number of unnecessary examinations. The Korean Society of Thyroid Radiology (KSThR) developed imaging guidelines for thyroid nodules and differentiated thyroid cancer using an adaptation process through a collaboration between the National Evidence-based Healthcare Collaborating Agency and the working group of KSThR, which is composed of radiologists specializing in thyroid imaging. When evidence is either insufficient or equivocal, expert opinion may supplement the available evidence for recommending imaging. Therefore, we suggest rating the appropriateness of imaging for specific clinical situations in this guideline.

Lung Metastasis in Children with Differentiated Thyroid Cancer: Factors Associated with Diagnosis and Outcomes of Therapy

Background: Lung metastasis from differentiated thyroid cancer (DTC) in children and young adults (CAYA) is estimated at 25%, which is 3-4 times higher than in adults. Lung metastases may respond to radioactive iodine (RAI) therapy and overall survival is excellent. Associations with lung metastasis include lateral lymph node (LN) disease although CAYA data are limited. We investigated factors associated with lung metastasis in children and adolescents and described their presentation and outcome. Methods: A retrospective review of medical records from 1998 to 2017 in patients aged <18 years treated at a tertiary pediatric center was carried out. Data on age, clinical features at diagnosis, histology, biochemistry, imaging, RAI therapy, and outcome were collected. Results: Patients treated for DTC totaled 98 and 19 of 98 (19%) patients had lung metastasis; 17 of 19 (89%) patients were identified within 6 months from thyroidectomy. Patients with lung metastasis were younger (p < 0.001)-40% <13 years old had lung metastasis-and had a larger primary tumor diameter (p = 0.01). Absence of LN disease had negative predictive values ≥90% (p < 0.02). Patients with lung metastasis had a higher postoperative thyrotropin-stimulated thyroglobulin (Tg) (p < 0.001), ≥2 ng/mL in 10 of 11 (91%) patients, and 100% had an elevated preoperative Tg (>60 ng/mL). Post-therapy whole body scan (WBS) identified most metastasis (13 of 17 patients), which were mostly diffuse (11 of 19 patients). Discordant findings were found between WBS and computed tomography (CT) at diagnosis (2 patients), WBS and CT during surveillance (3 patients), and diagnostic and post-therapy WBS (2 patients). Final outcome was "excellent" in 3 of 19 (16%) patients, "biochemically persistent" in 1 of 19 (5%) patients, "structurally persistent" in 13 of 19 (68%) patients-including 1 death-and indeterminate in 2 of 19 (11%) patients. Postoperative Tg correlated with response to therapy. Lung metastasis pattern and RAI cumulative activity were not predictive of response to therapy. Conclusions: Lung metastases are mostly observed at diagnosis of DTC and higher suspicion should be maintained in CAYA who are younger, have LN disease, and have elevated postoperative Tg. Preoperative Tg shows promise as another predictive marker, but limited sample size precludes generalization. "Excellent" response to therapy is uncommon-multiple RAI courses do not necessarily improve outcome-response appears unrelated to RAI activity or metastasis pattern.

Genomic landscape of metastatic papillary thyroid carcinoma and novel biomarkers for predicting distant metastasis

Papillary thyroid carcinoma (PTC) is the most common malignancy of the thyroid gland, with a relatively high cure rate. Distant metastasis (DM) of PTC is uncommon, but when it occurs, it significantly decreases the survival of PTC patients. The molecular mechanisms of DM in PTC have not been systematically studied. We performed whole exome sequencing and GeneseeqPrime (425 genes) panel sequencing of the primary tumor, plasma and matched white blood cell samples from 20 PTC with DM and 46 PTC without DM. We identified somatic mutations, gene fusions and copy number alterations and analyzed their relationships with DM of PTC. BRAF‐V600E was identified in 73% of PTC, followed by RET fusions (14%) in a mutually exclusive manner (P < 0.0001). We found that gene fusions (RET, ALK or NTRK1) (P < 0.01) and chromosome 22q loss (P < 0.01) were independently associated with DM in both univariate and multivariate analyses. A nomogram model consisting of chromosome 22q loss, gene fusions and three clinical variables was built for predicting DM in PTC (C‐index = 0.89). The plasma circulating tumor DNA (ctDNA) detection rate in PTC was only 38.9%; however, it was significantly associated with the metastatic status (P = 0.04), tumor size (P = 0.001) and invasiveness (P = 0.01). In conclusion, gene fusions and chromosome 22q loss were independently associated with DM in PTC and could serve as molecular biomarkers for predicting DM. The ctDNA detection rate was low in non–DM PTC but significantly higher in PTC with DM.

Clinicopathological Risk Factors for Distant Metastasis in Differentiated Thyroid Carcinoma: A Meta-analysis

INTRODUCTION

Distant metastasis (DM) is not a frequent event in differentiated thyroid carcinoma (DTC) but has an adverse impact on mortality of patients with DTC. In the current study, we aimed to conduct a comprehensive systematic review and meta-analysis to investigate the risk factors for DM in DTCs and for each histological subtype.

METHODS

Five electronic databases were searched from inception to December 2016 for relevant articles. Pooled odd ratios and 95% confidence interval were calculated using random-effect model.

RESULTS

Thirty-four articles with 73,219 patients were included for meta-analyses. In DTCs, male gender, age ≥45 years, tumor size ≥4 cm, multifocality, vascular invasion (VI), extrathyroidal extension (ETE), lymph node metastasis (LNM), and lateral LNM were demonstrated to be associated with significant risks for DM. In addition, several clinicopathological factors such as age ≥45 years, VI, ETE, and LNM were shown to be significant risk factors for DM in both PTC and FTC subgroups.

CONCLUSION

Our study demonstrated the promising value of several clinicopathological factors such as male gender, older age, VI, ETE, and LNM in predicting DM in PTCs and FTCs. Our study affirms the value of the selected clinicopathological factors for tumor risk stratification and assessment of patients' prognosis.

Efficacy of radioiodine therapy for treating 20 patients with pulmonary metastases from differentiated thyroid cancer and a meta-analysis of the current literature

Background

Radioiodine therapy (RAI) after total or near-total thyroidectomy is a recommended treatment for patients with pulmonary metastasis from differentiated thyroid cancer (DTC). However, the total effective rate of iodine-131 therapy remains controversial. This study aimed to determine the efficacy of RAI for treating patients with pulmonary metastasis from DTC, and to identify independent predictors of its efficacy.

Methods

We conducted a retrospective study to evaluate 20 patients with pulmonary metastasis from DTC who underwent RAI at our center at first and performed a meta-analysis to evaluate relevant literature regarding the overall efficacy of RAI and subgroup-specific efficacies subsequently.

Results

The efficacy rate at our center was 40%, and no significant differences were observed according to sex, age, pathological type, metastasis state, or interval between the initial RAI and final surgery. The meta-analysis revealed that the pooled overall efficacy rate was 58%, and significant differences were observed when we compared pulmonary metastasis versus pulmonary and other distant metastasis, age of < 40 years versus age of ≥ 40 years, papillary thyroid cancer versus follicular thyroid cancer and male patients versus female patients.

Conclusions

These results suggest that RAI is an effective treatment for patients with pulmonary metastasis from DTC after surgical treatment. The efficacy of RAI was significantly predicted by the presence of papillary thyroid cancer, age of < 40 years, the absence of non-lung distant metastasis and female patients.

Role of molecular markers to predict distant metastasis in papillary thyroid carcinoma: Promising value of TERT promoter mutations and insignificant role of BRAF mutations—a meta-analysis

The presence of distant metastasis is associated with an adverse outcome in papillary thyroid cancer. We performed a meta-analysis to investigate the role of molecular markers as predictors for distant metastasis in papillary thyroid cancer. Four electronic databases including PubMed, Web of Science, Scopus, and Virtual Health Library were searched, and odds ratio and its 95% confidence interval concerning the association of BRAF, RAS, and TERT promoter mutations and RET/PTC rearrangements with distant metastasis were calculated using random-effects model. In total, 42 studies with 11,109 papillary thyroid cancers were included for meta-analyses. Overall, the presence of TERT promoter (odds ratio = 5.95; 95% confidence interval = 2.95–11.99), RAS mutations (odds ratio = 2.5; 95% confidence interval = 1.00–6.22), and RET/PTC rearrangements (odds ratio = 1.92; 95% confidence interval = 1.03–3.56) were found to be associated with a significantly increased risk for distant metastasis. BRAF mutations were not associated with an elevated risk for distant metastasis (odds ratio = 0.79; 95% confidence interval = 0.54–1.16). In conclusion, our study demonstrated the promising value of few molecular biomarkers, especially TERT promoter mutations in predicting distant metastasis in papillary thyroid cancers, while BRAF mutations showed no association with distant metastasis. Our study affirms the value of selected mutations for tumor risk stratification and assessment of patients’ prognosis.

Predictors of incomplete response to therapy among Filipino patients with papillary thyroid cancer in a tertiary hospital

BACKGROUND

Although survival rate in papillary thyroid cancer (PTC) is high, the risk of persistence and recurrence together with the dramatic rise in its incidence cannot be overemphasized. Filipinos are considered to be at greater risk for negative outcomes. A paradigm shift in the management of PTC introduces re-stratification based on response to therapy which was reported to have better correlation with long-term outcome. The study aimed to identify predictors of incomplete response after thyroidectomy and radioiodine therapy among patients with PTC. The results of the study may have important implications in our understanding of the disease process allowing more aggressive treatment and monitoring of certain subgroups of patients.

METHODOLOGY

Retrospective review of 225 patients with PTC (59% ATA low risk, 30 % ATA intermediate risk and 11% ATA high risk) who underwent thyroidectomy and radioiodine therapy was performed. Thirteen variables were considered (age, gender, histopathological variant, stage, extent of disease, MACIS score, AMES score, primary tumour size, lymph node, lymphovascular invasion, bilaterality, multifocality and preoperative TSH level). Logistic regression analysis using Backward Wald algorithm was used to identify independent predictors of incomplete response to therapy after 24 months.

RESULTS

Of the 225 patients, 69 (31%) had incomplete response. Biochemical and structural (predominantly thyroid bed, lung and bone) incomplete response was observed in 6 and 63 patients, respectively. Incomplete response was documented in 8, 54 and 92% of low-, intermediate- and high-risk patients based on ATA recommendation. Incomplete response was significantly dependent on gender, lymph node involvement and location, extent of malignancy and multifocality taking into account the size of concurrent tumours (p < 0.05). The model was found to have high sensitivity (71%) and specificity (96%).

CONCLUSION

A significant fraction of PTC patients experienced incomplete response to therapy. Our data suggest that male gender, lateral or mediastinal lymph node involvement, class III extent of disease by De Groot and multifocality with concurrent tumour or tumours more than 1 cm are major predictors of incomplete response. Not all predictors of recurrence and mortality are consistent predictors of treatment response which may be equally important in a disease with low mortality but significant morbidity like PTC.

Lymph node status of lateral neck compartment in patients with N1b papillary thyroid carcinoma

Conclusion Loco-regional recurrence-free survival was significantly decreased in the papillary thyroid cancer patients with > 6 metastatic lymph nodes and a lymph node ratio > 0.22. Also, the risk of lung metastasis was significantly increased in cases with bilateral neck node metastases. Objective This study focused on the metastatic lymph node status of the lateral neck compartment to understand its prognostic significance for loco-regional recurrence and distant metastasis. Methods Between January 2004 and December 2009, 1040 patients were diagnosed with papillary thyroid cancer and underwent treatment. Results In a multivariate analysis, sex, the number of metastatic lymph nodes, and the lymph node ratio was significantly associated with loco-regional recurrence. The sensitivity/specificity of > 6 metastatic lymph nodes for predicting recurrence was 64.0%/69.7%. The 5-year loco-regional recurrence-free survival of patients with 0-6 metastatic lymph nodes and > 6 metastatic lymph nodes were 93.4% and 79.2%, respectively. The 5-year loco-regional recurrence-free survival of patients with a lymph node ratio ≤ 0.22 and a lymph node ratio > 0.22 were 97.1% and 78.8%, respectively. In the multivariate analysis, only bilateral neck node metastases were significantly associated with lung metastasis.

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.

Ultrasonographic findings relating to lymph node metastasis in single micropapillary thyroid cancer

Background

In thyroid cancer, preoperative ultrasonography (US) is performed to detect the primary tumor and lymph node metastasis (LNM), which are related to prognosis. This study examined the relationships between specific US findings and LNM in micropapillary thyroid cancer (MPTC).

Methods

Data on 220 patients with solitary MPTC who underwent total thyroidectomy and neck dissection between 2008 and 2009 were evaluated retrospectively. We classified the US findings according to the nature, shape, echogenicity, extent, margin, and calcification of the primary tumor and evaluated the correlations between these findings and those of LNM.

Results

Hypoechogenicity (odds ratio = 2.331, P = 0.025) and marked hypoechogenicity (OR = 4.032, P = 0.016) of MPTC were risk factors for central LNM. All of the patients with lateral cervical LNM showed hypoechogenicity or marked hypoechogenicity. Hypoechogenicity (odds ratio = 5.349, P = 0.047) and other types of calcification (odds ratio = 2.495, P = 0.010) were significant risk factors for lateral cervical LNM.

Conclusions

Specific sonographic findings (hypoechogenicity or marked hypoechogenicity, and calcification) suggest LNM.

Clinical characteristics of papillary thyroid microcarcinoma less than or equal to 5 mm on ultrasonography

Management of papillary thyroid microcarcinoma sized ≤5 mm identified on ultrasonography is controversial. In this study, we evaluated the clinical characteristics of papillary thyroid microcarcinoma sized ≤5 mm on ultrasonography in comparison to those >5 mm and sought to present rationales for optimal management in papillary thyroid microcarcinoma ≤5 mm. The medical records of 396 patients who underwent surgery for papillary thyroid carcinoma between 2009 and 2011 were retrospectively analyzed. The patients were grouped into A (≤5 mm, n = 132) or B (>5 mm, n = 264) and the clinicopathologic characteristics of the patients were reviewed and compared between the two groups. Tumor capsular invasion (45.5 vs. 59.8 %, p = 0.007) and cervical lymph node metastasis (18.2 vs. 29.2 %, p = 0.018) were more frequent in group B. Nonetheless, group A presented lymph node metastasis in 42.3 % of multifocal cases showing no difference to that of group B (41.5 %, p = 0.946) and also included five cases (3.8 %) of lateral neck metastasis. Multifocality was the only predictive factor for lymph node metastasis in group A (p < 0.001). Over half (55.3 %) of the patients of group A were diagnosed with papillary carcinoma in private clinics; however, only 5.5 % of these patients underwent assessment of lateral neck lymph nodes initially. In conclusion, higher risk of cervical lymph node metastasis should be considered in evaluation and surgical decision of papillary thyroid microcarcinoma ≤5 mm identified on ultrasonography with multifocality. Evaluation of the cervical lymph nodes including the lateral neck should not be overlooked when suspicious thyroid nodule suggesting malignancy sized ≤5 mm shows multifocal lesions.

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

CONTEXT

A prognostic classification system based on aggregate numbers of lymph node metastases may better estimate the risk of distant metastasis.

OBJECTIVE

This investigation sought to evaluate a papillary thyroid cancer (PTC) patient's risk of distant metastasis.

DESIGN

This was a retrospective analysis.

SETTING

The setting was a tertiary referral center.

PATIENTS

Included were 972 PTC patients.

INTERVENTION

The intervention was compartment-oriented surgery.

MAIN OUTCOME MEASURE

The main outcome measure was lung, bone, and liver metastasis.

RESULTS

Eighty-seven (9.0%) of the 972 PTC patients had distant metastases to lung (79 patients), bone (16 patients), liver (two patients), brain and skin (one patient each). For distant metastasis, more than 20 lymph node metastases had a specificity of 90.8% and a negative predictive value of 92.7%, whereas sensitivity and positive predictive value were low (27.6 and 22.9%). On multivariate logistic regression, 1-5, 6-10, and 11-20 involved nodes denoted a moderate risk of lung metastasis [odds ratio (OR), 9.9, 10.6, and 13.8; P ≤ 0.004], whereas more than 20 involved nodes indicated a high risk of lung metastasis (OR, 25.0; P < 0.001). Mediastinal lymph node metastasis carried a moderate risk of lung metastasis (OR, 7.5; P = 0.001). When these numeric categories of lymph node metastases were exchanged for current tumor node metastasis (TNM) N categories, the OR decreased from 25.0 (for > 20 lymph node metastases) to 16.4 (N1b), and from 9.9-13.8 (for 1-20 lymph node metastases) to 4.7 (N1a).

CONCLUSION

In PTC, categories of 0, 1-20, and more than 20 lymph node metastases correlate better with lung metastasis than current TNM N categories N0, N1a, and N1b.

Gender-Specific Variation in the Prognosis of Papillary Thyroid Cancer TNM Stages II to IV

To investigate the correlation between gender and the clinical presentation of papillary thyroid cancer and the long-term followup results, 435 patients who underwent total or near-total thyroidectomy were enrolled in this study. Among these papillary thyroid cancer patients, 12.2% showed lymph node metastases and a higher incidence of male patients in the N1b group. There were 65 from 316 female (20.6%) and 49 from 120 male (40.8%) patients who had a postoperative disease progression. A total of 55 (12.6%) patients died of thyroid cancer. Male patients showed a higher thyroid cancer mortality than the females. Multiple regression analysis showed that male gender was an independent risk factor for cancer recurrence and mortality. Male patients with TNM stages II to IV of papillary thyroid cancer need to adopt aggressive surgical and postoperative (131)I therapy.