Outcomes of patients with differentiated thyroid cancer risk-stratified according to the American thyroid association and Latin American thyroid society risk of recurrence classification systems

Dynamic risk assessment in patients with differentiated thyroid cancer

The current approach for patients with differentiated thyroid carcinoma should be individualized according to the risk of recurrence, and this stratification could be used to identify the risk of persistent/recurrent disease in three scenarios: preoperatively, immediately postoperatively, and during long-term follow-up. The initial risk of recurrence will tailor the management of the patient in the preoperative and immediate postoperative settings, while the dynamic risk, which considers the responses to treatment, could guide the decision-making process for remnant ablation and long-term management.This review provides a summary of the existing information regarding the dynamic risk of recurrence and recommended management for patients with differentiated thyroid cancer. The application of this approach is essential to avoid unnecessary treatments for most patients who will have a favorable prognosis. On the other hand, it allows specific therapeutic interventions for those patients at high risk of recurrence. In the future, analysis of tumor biology and prospective studies will surely improve the accuracy of recurrence risk prediction.

Preoperative risk stratification for patients with ≤ 1 cm papillary thyroid carcinomas based on preoperative blood inflammatory markers: construction of a dynamic predictive model

Objective

The aim of this study was to investigate the relationships and predictive value of preoperative peripheral blood inflammatory markers as a means by which to assess risk for patients with ≤ 1 cm papillary thyroid carcinomas (PTCs). In addition, a preoperative risk stratification predictive model was constructed and validated.

Methods

Clinical and pathologic data, as well as preoperative blood specimens, were collected from patients who underwent initial thyroid cancer surgery at the Hangzhou First People's Hospital, from January 2014 to January 2023. Risk assessment was performed based on postoperative pathology according to the 2015 ATA guidelines for recurrence risk stratification. Using univariate analysis and multivariate logistic regression, we identified independent risk factors associated with risk stratification. A predictive model was established and its discriminative and calibration abilities were validated. An independent validation dataset was used to verify the model, and the model was deployed as an online calculator.

Results

A total of 1326 patients were included in the study, with 1047 cases (79.0%) classified as low risk and 279 cases (21.0%) classified as intermediate to high risk. The modeling group consisted of 981 cases, through univariate analysis and multivariate logistic regression analysis, preoperative blood Neutrophil/Lymphocyte Ratio (NLR), gender, tumor diameter, and multifocality were identified as independent risk factors that distinguished between low and intermediate to high risk patients with ≤ 1 cm PTCs. The clinical predictive model exhibited an AUC of 0.785, specificity of 70.6%, and sensitivity of 75.8%. For the independent validation group of 345 patients, the AUC was 0.813, specificity was 83.8%, and sensitivity was 70.4%. The calibration curve and clinical decision curve indicate that the model demonstrates excellent calibration performance.

Conclusion

A dynamic clinical predictive model based on preoperative blood NLR and clinical information for patients with ≤ 1 cm PTCs was established. The model is useful for preoperative risk assessment of patients with ≤ 1 cm PTCs.

The American Thyroid Association risk stratification and long-term outcomes of differentiated thyroid cancer: a 20-year follow-up of patients in Saudi Arabia

Background

Studies have reported differing factors associated with poor outcomes in patients with differentiated thyroid cancer (DTC). We aimed to describe our 20 years of experience in the management of thyroid cancer (TC) and identify predictors of treatment outcomes.

Methods

We conducted a retrospective review of medical records of patients with TC seen in the Thyroid Center at King Saud University Medical City (KSUMC) in Riyadh, Saudi Arabia, between the years 2000 and 2020. Demographic and clinical data including pathological characteristics were collected. The American Thyroid Association (ATA) risk stratification was determined for all patients at the postoperative period as well as the response to therapy at the final follow-up visit.

Results

A total of 674 patients (mean age: 47.21 years) with TC, 571 (84.7%) of which were women, were included. There were 404 (60.0%) patients with ATA low risk, 127 (18.8%) with intermediate risk, and 143 (21.2%) with high-risk histology. Overall, 461 patients (68.4%) had an excellent response to treatment, 65 (9.6%) had an indeterminate response, 83 (12.3%) had a biochemical incomplete response, and 65 (9.6%) had a structural incomplete response. Patients who had an excellent response were mostly ATA low risk (n = 318 of 431, 68.1%), whereas 40 of 65 patients (61.5%) of those with ATA high-risk histology had a structural incomplete response to treatment. There were significantly more women who had an excellent response compared with men. Obesity, lymphovascular invasion, and size of the tumor were significant predictors of worse outcomes to therapy.

Conclusion

Tumor size, lymphovascular invasion, and obesity are strong predictors of a worse response to therapy among patients with TC. Patients with obesity should be carefully followed up regardless of their risk stratification in light of the recent compelling evidence associating obesity with thyroid cancer and its higher risk of a worse disease outcome. ATA risk stratification is well correlated with patient long-term outcomes.

Assessing the role of central lymph node ratio in predicting recurrence in N1a low-to-intermediate risk papillary thyroid carcinoma

Introduction

Lymph node metastasis in patients with papillary thyroid carcinoma (PTC) is associated with postoperative recurrence. Recently, most studies have focused on the evaluation of recurrence in patients with late-stage PTC, with limited data on those with early-stage PTC. We aimed to assess the relationship between lymph node ratio (LNR) and recurrence in low-to-intermediate-risk patients and validate its diagnostic efficiency in both structural (STR) and biochemical recurrence (BIR).

Methods

Clinical data of patients with PTC diagnosed at the Affiliated Hospital of Jining Medical University were retrospectively collected. The optimal LNR cut-off values for disease-free survival (DFS) were determined using X-tile software. Predictors were validated using univariate and multivariate Cox regression analyses.

Results

LNR had a higher diagnostic effectiveness than metastatic lymph nodes in patients with low-to-intermediate recurrence risk N1a PTC. The optimal LNR cutoff values for STR and BIR were 0.75 and 0.80, respectively. Multivariate Cox regression analysis showed that LNR≥0.75 and LNR≥0.80 were independent factors for STR and BIR, respectively. The 5-year DFS was 90.5% in the high LNR (≥0.75) and 96.8% in low LNR (<0.75) groups for STR. Regarding BIR, the 5-year DFS was 75.7% in the high LNR (≥0.80) and 86.9% in low LNR (<0.80) groups. The high and low LNR survival curves exhibited significant differences on the log-rank test.

Conclusion

LNR was associated with recurrence in patients with low-to-intermediate recurrence risk N1a PTC. We recommend those with LNR≥0.75 require a comprehensive evaluation of lateral neck lymphadenopathy and consideration for lateral neck dissection and RAI treatment.

Utilizing Dynamic Risk Stratification in Patients With Tall Cell Variant Papillary Thyroid Cancer

OBJECTIVES

Tall cell variant (TCV) papillary thyroid cancer (PTC) is a subtype of PTC associated with aggressive tumor behavior, advanced stage, and higher rates of recurrence and mortality. The present study aimed to test an established dynamic risk stratification tool in the TCV population, with the goal of better predicting the postoperative course of these patients.

STUDY DESIGN

Retrospective chart review.

METHODS

A total of 94 patients with TCV who underwent total thyroidectomy with radioactive iodine ablation were retrospectively reviewed from 1998 through 2020. Biochemical, structural, and overall response to treatment was determined for each patient, based on postoperative thyroglobulin levels and imaging findings. Primary outcomes were locoregional and distant recurrence, presence of disease at final follow-up, need for additional intervention, and disease-specific mortality.

RESULTS

Patients with TCV who were stratified as having an excellent overall response to treatment had lower rates of locoregional recurrence than indeterminate, biochemical incomplete, and structural incomplete responses (2.0%, 33.3%, 55.0%, and 85.7% at 5 years respectively, p < 0.001). The same was true for distant recurrence as well (2.0%, 9.0%, 35.1%, and 42.9%, p < 0.001). An excellent response was also associated with lower rates of presence of disease at final follow-up, need for additional intervention, and disease-specific mortality.

CONCLUSIONS

Although TCV is an aggressive subtype associated with worse clinical outcomes than classical PTC, patients with an excellent overall response to treatment have significantly improved outcomes when compared to indeterminate, biochemical incomplete, and structural incomplete responses.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:2430-2438, 2023.

A Data-Driven Approach to Refine Predictions of Differentiated Thyroid Cancer Outcomes: A Prospective Multicenter Study

CONTEXT

The risk stratification of patients with differentiated thyroid cancer (DTC) is crucial in clinical decision making. The most widely accepted method to assess risk of recurrent/persistent disease is described in the 2015 American Thyroid Association (ATA) guidelines. However, recent research has focused on the inclusion of novel features or questioned the relevance of currently included features.

OBJECTIVE

To develop a comprehensive data-driven model to predict persistent/recurrent disease that can capture all available features and determine the weight of predictors.

METHODS

In a prospective cohort study, using the Italian Thyroid Cancer Observatory (ITCO) database (NCT04031339), we selected consecutive cases with DTC and at least early follow-up data (n = 4773; median follow-up 26 months; interquartile range, 12-46 months) at 40 Italian clinical centers. A decision tree was built to assign a risk index to each patient. The model allowed us to investigate the impact of different variables in risk prediction.

RESULTS

By ATA risk estimation, 2492 patients (52.2%) were classified as low, 1873 (39.2%) as intermediate, and 408 as high risk. The decision tree model outperformed the ATA risk stratification system: the sensitivity of high-risk classification for structural disease increased from 37% to 49%, and the negative predictive value for low-risk patients increased by 3%. Feature importance was estimated. Several variables not included in the ATA system significantly impacted the prediction of disease persistence/recurrence: age, body mass index, tumor size, sex, family history of thyroid cancer, surgical approach, presurgical cytology, and circumstances of the diagnosis.

CONCLUSION

Current risk stratification systems may be complemented by the inclusion of other variables in order to improve the prediction of treatment response. A complete dataset allows for more precise patient clustering.

Modified dynamic risk stratification system further predicts individual outcome in patients with intermediate-risk papillary thyroid cancer

OBJECTIVE

We assessed the contribution of initial treatment response to further refining prediction of individual outcomes in intermediate-risk papillary thyroid cancer (PTC) on the American Thyroid Association (ATA) risk stratification system. Dynamic risk stratification (DRS) as originally proposed by Tuttle et al. in 2010 was modified to also include serum antithyroglobulin antibodies (TgAb) as a surrogate marker of the likelihood of persistent disease, specifically in patients with thyroglobulin assay interference by TgAb.

METHODS

Three hundred and seventy-three patients with ATA intermediate-risk PTC were enrolled retrospectively upon reviewing medical records. Patients were followed at the National Cancer Institute in Bogota, Colombia after being treated with total thyroidectomy and I-131 therapy between 2009 and 2013. Best response to initial therapy was classified as excellent, indeterminate, biochemically incomplete or structurally incomplete. Final disease status after a median follow-up of 7.1 years was classified as no evidence of disease (NED), indeterminate, or persistent disease (either biochemically or structurally). The rate of recurrence was determined in excellent responders.

RESULTS

Excellent response was achieved by 164 patients (43.9%). At a median follow-up of 42 months, 19 (11.6%) had experienced recurrence. 87.4% of initially excellent responders available at the final checkpoint were NED, compared to 28% of those with biochemically or structurally incomplete response and to 60.2% of all ATA intermediate-risk PTC patients in our cohort.

CONCLUSIONS

Modified DRS further predicted individual outcomes in intermediate-risk PTC, potentially allowing ongoing management to be tailored accordingly.

Is radioiodine ablation with 1.1 GBq (30 mCi) 131I necessary in low-risk thyroid cancer patients? Results from a long-term follow-up prospective study

BACKGROUND

In patients with low-risk differentiated thyroid cancer (DTC), remnant ablation with radioiodine (RA) after total thyroidectomy (TT) is controversial. No benefits have been demonstrated in terms of mortality or disease-free survival. Recent evidence found that RA did not improve mid-term outcomes.

PURPOSE

To evaluate initial response to treatment and long-term follow-up status in low-risk DTC patients after TT vs. TT + RA with ¹³¹I 1.11 GBq (30 mCi).

METHODS

Prospective multicenter non-randomized study; 174 low-risk DTC that underwent TT were recruited an divided in two groups according to RA (87 ablated and 87 non-ablated). Response to treatment was evaluated at 6-18 months after thyroidectomy and at the end of follow-up with measurements of thyroglobulin, and anti-thyroglobulin antibodies levels, and neck ultrasonography.

RESULTS

Baseline characteristics of both groups were similar. Ablated patients: median age 45.5 years, 84% females, 95.4% papillary thyroid carcinoma (PTC), mean tumor size 16 mm; non-ablated: median age 45 years, 88.5% females, 96.6% PTC, mean tumor size 14 mm. Response to initial treatment was similar between both groups, with < 2% of structural incomplete response. Final status was evaluated in 139 cases (median follow-up of 60 months). Among ablated patients, 82.8% had no evidence of disease (NED), 12% had an indeterminate response (IR) and 5% a biochemical incomplete response (BIR). Non-ablated patients had NED in 90%, IR in 8.7% and BIR in 1.2%. No statistical difference was found between groups (p = 0.29). No patient had evidence of structural disease at the end of follow-up.

CONCLUSIONS

Our findings support the recommendation against routine RA in low-risk DTC patients.

Migration of Risk Classification Between the JAES Versus ATA guidelines for Papillary Thyroid Carcinoma

BACKGROUND

This study aimed to investigate outcomes in the same cohort of patients with papillary thyroid carcinoma (PTC) risk-stratified according to the Japan Association of Endocrine Surgery (JAES) and American Thyroid Association (ATA) guidelines.

METHODS

A total of 1044 patients with PTC who underwent initial thyroidectomy at Yokohama City University Medical Center between January 2000 and June 2022 were included.

RESULTS

According to the JAES guidelines, 480 (46%), 386 (37%), and 178 (17%) patients were classified as low, intermediate, or high risk, respectively. Furthermore, according to the ATA guidelines, 590 (57%), 261 (25%), and 193 (18%) patients were reclassified as low, intermediate, or high risk, respectively. Among 1044 patients with PTC, the 10-year cause-specific survival (CSS) rates of patients with JAES low and intermediate risk were 99.7 and 98.6%, respectively, and there was no statistically difference (p = 0.096). However, the 10-year CSS rates of patients with ATA low and intermediate risk were 100 and 99.5%, respectively (p = 0.007). Among 1001 patients with M0 PTC, the 10-year distant metastasis-free survival (DMFS) rates of patients with JAES intermediate and high risk were 94.2, and 76.7%, respectively (p < 0.001). However, the 10-year DMFS rates of patients with ATA intermediate and high risk were 88.1 and 86.6%, respectively (p = 0.233), and there was no statistically difference.

CONCLUSIONS

Both JAES and ATA risk classifications properly stratified the PTC patients. Furthermore, the ATA risk classification more precisely extracted patients with better and worse prognoses.

Application of the American Thyroid Association Risk Assessment in Patients with Differentiated Thyroid Carcinoma in a German Population

Background: The American Thyroid Association (ATA) uses criteria to assess the risk for persistent disease in differentiated thyroid carcinoma (DTC) after radioiodine therapy (RAI). There are no data available showing that this classification can be adopted unadjusted by Germany. Aim: The aim of our study is to investigate whether the ATA classification can be applied to a German population for short-term prognosis. Furthermore, we investigated the influence of an age cutoff value. Methods: We retrospectively analyzed 121 patients who were referred to our tertiary referral center. Patients were classified into risk categories, and the therapy response was determined according to ATA. Results: A total of 73/83 (88%) ATA low-risk patients and 12/19 (63%) intermediate-risk patients showed an excellent response; 2/19 (11%) high-risk patients had a biochemical, and 6 (31%) had a structural incomplete response. Of all 39 patients ≥55 years, 84% had an excellent response. Using a cut off of 50 years, 50/62 (81%) of the older patients showed an excellent response. Conclusion: The ATA risk classification is able to estimate the response to RAI therapy in a German population. A shift from 55 to 50 years as an age cutoff value does not result in any relevant change in the treatment response.

circRNA mannosidase alpha class 1A member 2 contributes to the proliferation and motility of papillary thyroid cancer cells through upregulating metadherin via absorbing microRNA-449a

Papillary thyroid carcinoma (PTC) is a common malignancy in endocrine system globally. Accumulating articles have found that circular RNAs (circRNAs) were dysregulated, and they were involved in PTC development. The aim of this project was to explore the function and associated mechanism of circRNA mannosidase alpha class 1A member 2 (circMAN1A2) in PTC progression. The expression of RNA was determined by real-time quantitative PCR. Cell proliferation ability was analyzed by colony formation assay and 5-ethynyl-2'-deoxyuridine assay. Cell migration and invasion were assessed by wound healing assay and transwell invasion assay, respectively. Protein levels were determined by Western blot assay. Dual-luciferase reporter assay and RNA immunoprecipitation assay were applied to confirm the interaction between microRNA-449a (miR-449a) and circMAN1A2 or metadherin (MTDH). Xenograft tumor model was utilized to explore the effect of circMAN1A2 silencing on tumor growth in vivo . CircMAN1A2 expression was elevated in PTC specimens and three PTC cell lines relative to adjacent normal specimens and Nthy-ori 3-1 cell line. CircMAN1A2 silencing inhibited the proliferation and motility of PTC cells. CircMAN1A2 acted as a molecular sponge of miR-449a, and circMAN1A2 knockdown suppressed PTC development partly through upregulating miR-449a. MiR-449a bound to the 3' untranslated region of MTDH, and miR-449a restrained PTC progression partly through down-regulating MTDH. CircMAN1A2 interference suppressed PTC progression in vivo . CircMAN1A2 contributed to the proliferation ability and motility of PTC cells through enhancing MTDH expression via sponging miR-449a.

Evaluating Disease Specific Survival Prediction of Risk Stratification and TNM Systems in Differentiated Thyroid Cancer

BACKGROUND

Many countries have national guidelines for the management of differentiated thyroid cancer (DTC), including a risk stratification system to predict recurrence of disease. Studies whether these guidelines could also have relevance, beyond their original design, in predicting survival are lacking. Additionally, no studies evaluated these international guidelines in the same population, nor compared them to the TNM system. Therefore, we investigated the prognostic value of six stratification systems employed by ten International guidelines, and the TNM system with respect to predicting disease specific survival (DSS).

METHODS

We retrospectively studied adult patients with DTC from a Dutch university hospital. Patients were classified using the risk classification described in the British, Dutch, French, Italian, Polish, Spanish, European Society of Medical Oncology, European Thyroid Association, and 2009 and 2015 American Thyroid Association (ATA) guidelines, and the latest TNM system. DSS was analyzed using the Kaplan-Meier method, and the statistical model performance using the C-index, AIC, BIC and PVE.

RESULTS

We included 857 patients with DTC (79% PTC, 21% FTC). Median follow-up was 9 years, and 67 (7.8%) died due to DTC. The Dutch guideline had the worst statistical model performance, while the 2009 ATA/2014 British guideline had the best. However, the (adapted) TNM system outperformed all stratification systems.

CONCLUSIONS

In a European population of patients with DTC, out of ten International guidelines employing six risk of recurrence stratification systems and one mortality based stratification system, our optimized age-adjusted TNM system (8th edition) outperformed all other systems.

Incomplete response to therapy in intermediate- and high-risk thyroid cancer

CONTEXT

The American Thyroid Association (ATA) risk stratification system predicts risk of recurrence of differentiated thyroid cancer (DTC). Although the majority of patients achieve an excellent response, patients with intermediate- or high-risk DTC are at a significant risk of developing incomplete responses. We undertook this work to understand the factors associated with development of biochemically or structurally incomplete response in these two risk subgroups of DTC.

PATIENTS AND METHODS

We retrospectively reviewed 287 consecutive patients with intermediate- (213 patients) or high-risk (74 patients) DTC. All patients underwent total thyroidectomy with (223 patients) or without (64 patients) lymph node dissection and 94% of them received at least one dose of I-131ablation/therapy. Univariate and multivariate analysis and Kaplan Meier analysis were used to compare patients who achieved an excellent response with those who continued to have biochemically or structurally incomplete responses.

RESULTS

In univariate and multivariate analyses, age (P 0.002, Odds ratio 4.8, 95% CI: 1.8-12.9), tumor size (P 0.027, Odds ratio 1.30, 95% CI: 1.03-1.64) and distant metastases (P &lt; 0.0001, Odds ratio 44.6, 95% CI: 10.7-184.5) were significantly associated with the risk of developing biochemically or structurally incomplete statuses. Patients ≥ 55 years, tumors &gt; 2.5 cm and presence of distant metastasis were associated with higher risk of incomplete response and death from DTC. However, when this analysis was performed on intermediate and high-risk groups separately, only age was consistently associated with risk of biochemically or structurally incomplete response in either and both groups.

CONCLUSION

Age is a strong predictor of biochemically and structurally incomplete responses in patients with intermediate and high-risk DTC.

Serum glycomic profile as a predictive biomarker of recurrence in patients with differentiated thyroid cancer

PURPOSE

Thyroid cancer recurrence following curative thyroidectomy is associated with increased morbidity and mortality, but current surveillance strategies are inadequate for early detection. Prior studies indicate that tissue glycosylation is altered in thyroid cancer, but the utility of serum glycosylation in thyroid cancer surveillance remains unexplored. We therefore assessed the potential utility of altered serum glycomic profile as a tumor-specific target for disease surveillance in recurrent thyroid cancer.

EXPERIMENTAL DESIGN

We employed banked serum samples from patients with recurrent thyroid cancer post thyroidectomy and healthy controls. N-glycans were enzymatically released from serum glycoproteins, labeled via permethylation, and analyzed by MALDI-TOF mass spectrometry. Global level and specific subtypes of glycan structures were compared between patients and controls.

RESULTS

We evaluated 28 independent samples from 13 patients with cancer recurrence and 15 healthy controls. Global features of glycosylation, including N-glycan class and terminal glycan modifications were similar between groups, but three of 35 individual glycans showed significant differences. The three glycans were biosynthetically related biantennary core fucosylated N-glycans that only varied by the degree of galactosylation (G0F, G1F, and G2F; G: galactose, F: fucose). The ratio of G0F:G1F that captures reduced galactosylation was observed in patients samples but not in healthy controls (p = 0.004) and predicted thyroid cancer recurrence (AUC = 0.82, CI 95% = 0.64-0.99).

CONCLUSIONS

Altered N-glycomic profile was associated with thyroid cancer recurrence. This serum-based biomarker would be useful as an effective surveillance tool to improve the care and prognosis of thyroid cancer after prospective validation.

Cell-Free DNA Analysis within the Challenges of Thyroid Cancer Management

Simple Summary

Liquid biopsy is a minimally invasive method that emerged as a new promising tool for improving diagnosis, risk stratification, follow-up, and treatment of cancer patients. To date, the majority of the research in the area of liquid biopsy has focused on plasma-based cell-free DNA as a potential surrogate for tumor DNA obtained from a tissue biopsy. In the last decades, breakthrough advancements have been performed in the knowledge of thyroid cancer genetics, and the role of molecular characterization in clinical decision-making is continuously rising, from diagnosis completion to the personalization of treatment approach. Hence, it is expectable for cell-free DNA to be applicable in thyroid cancer management. This review aims to investigate the cell-free DNA utility for thyroid cancer patients’ care.

Abstract

Thyroid cancer is the most frequent endocrine malignancy with an increasing incidence trend during the past forty years and a concomitant rise in cancer-related mortality. The circulating cell-free DNA (cfDNA) analysis is a patient’s friendly and repeatable procedure allowing to obtain surrogate information about the genetics and epigenetics of the tumor. The aim of the present review was to address the suitability of cfDNA testing in different forms of thyroid cancer, and the potential clinical applications, as referred to the clinical weaknesses. Despite being limited by the absence of standardization and by reproducibility and validity issues, cfDNA assessment has great potential for the improvement of thyroid cancer management. cfDNA may support the pre-surgical definition of thyroid nodules by complementing invasive thyroid fine needle aspiration cytology. In addition, it may empower risk stratification and could be used as a biomarker for monitoring the post-surgical disease status, both during active surveillance and in the case of anti-tumor treatment.

An immediate postoperative response to therapy assessment can help avoid unnecessary RAI therapy

Background

Radioiodine (RAI) therapy plays a vital role in the postoperative treatment of differentiated thyroid cancer (DTC) patients underwent total thyroidectomy (TT). However, even in the presence of capsular invasion and lymph node metastasis prognosis can be excellent and a postoperative RAI treatment might not be necessary for all patients. Therefore, this study explored the criteria for avoiding unnecessary RAI therapy in these patients.

Method

We applied response to therapy assessment immediately after surgery and prospectively recruited 179 excellent or indeterminate response DTC patients with capsular invasion and/or LNM who underwent TT without RAI therapy. During the follow-up, thyroglobulin (Tg), thyroglobulin antibody (TgAb) levels, and cervical ultrasonography were collected and analyzed. Disease-free survival (DFS) was calculated using the Kaplan-Meier method. In addition, response to therapy assessments was performed on patients during each follow-up.

Results

The mean follow-up period was 29.85 ± 17.44 months, and the 3- and 5-year DFS for all the patients was 99.3% in each. At the last follow-up, 165 (92.2%) patients had excellent responses, while 12 (6.7%) had an indeterminate response, and one (0.6%) each had biochemical and incomplete responses. No significant difference was observed in response to therapy between the subgroups of LNM and tumor invasion (P>0.05). For patients with capsular invasion and a number of metastatic lymph nodes ≤5 and >5, the proportions of recorded excellent responses were 95.9%, 91.0%, and 85.7%, respectively. Better responses were observed in females (excellent response: 95.5%, P=0.023), patients with stimulated Tg (s-Tg) ≤1ng/ml (excellent response: 100%, P<0.001), s-Tg ≤ 2ng/ml (excellent response: 98.4%, P<0.001), and excellent response for the immediate postoperative assessment (excellent response: 98.5%, P=0.004).

Conclusions

The current study suggested that the response to therapy assessment immediately applied postoperatively could help avoid unnecessary RAI therapy among DTC patients with capsular invasion and/or LNM. Moreover, excellent response patients and patients with indeterminate response and s-Tg ≤ 2ng/ml could be managed without RAI therapy.

The Role of American Thyroid Association Pediatric Thyroid Cancer Risk Stratification and BRAFV600E Mutation in Predicting the Response to Treatment in Papillary Thyroid Cancer Patients ≤18 Years Old

OBJECTIVE

This study aimed to evaluate the role of risk stratification by the American Thyroid Association (ATA) pediatric thyroid cancer risk levels and BRAF^V600E mutation to predict the response to treatment in papillary thyroid cancer (PTC) patients ≤18 years old.

METHODS

Clinical outcomes during a median period of 6 (2-21.8) years were assessed in 70 patients, according to ATA pediatric risk stratification, BRAF^V600E mutation status, and dynamic risk stratification (DRS) at final follow-up.

RESULTS

Of 70 patients, 44 (63%), 14 (20%), and 12 (17%) were classified initially as low-, intermediate-, and high-risk, respectively. BRAF^V600E mutation analysis data was available in 55 (78.6%) patients, of whom 18 (32.7%) had the BRAF^V600E mutation. According to the final DRS, 61 (87%), two (3%), six (9%), and one (1%) patients were classified as an excellent, incomplete biochemical, incomplete structural, and indeterminate response, respectively. All ATA low-risk patients showed excellent response to treatment, whereas the rate of excellent response was 65.4% in intermediate- and high-risk levels (p<0.001). The rates of excellent response in BRAF^V600E positive and negative patients were 83% and 92%, respectively (p=0.339). The rate of locoregional recurrence was significantly higher in BRAF^V600E positive vs negative patients (33.3% vs 2.7% respectively, p=0.001).

CONCLUSION

ATA pediatric risk stratification is effective in predicting response to treatment in PTC patients ≤18 years old. The presence of BRAF^V600E mutation was highly predictive for recurrence but had no significant impact on the rate of excellent response to treatment at final follow-up.

AST/ALT (De Ritis) Ratio in Early Stage Differentiated Thyroid Cancer

Objective: Differentiated thyroid cancers are the most common endocrine cancers and their frequency is increasing with the increase in imaging possibilities. In various malignancies; Even in the absence of liver metastases, it was determined that AST value increased compared to ALT due to increased metabolism, tissue damage and rapid tumor turnover. This rate is known as the De Ritis rate, and in our study, we planned to evaluate whether there is a relationship between histopathological subtype, multifocality, disease stage and risk group and AST/ALT (De Ritis) ratio in early stage thyroid cancers. Method: A total of 154 patients diagnosed with differentiated thyroid cancer in our clinic between 2016 and 2019 were included in the study. The AST/ALT ratios of the patients in the preoperative period were recorded. Tumor staging of each patient was performed according to the American Joint Cancer Committee (AJCC) 8 by evaluating the postoperative pathology reports. The correlation between the patients' preoperative De Ritis rates and postoperative staging was evaluated. Results: In our study, the mean De Ritis value of the patients was found to be 1.18. The rate of patients with De Ritis rate ≥1.5 was 15.9%. There was no statistically significant difference between preoperative De Ritis rate and histopathological subtype, vascular invasion, capsule invasion, tumor diameter, lymph node involvement and tumor stage. Conclusion: In our study it was found that preoperative De Ritis ratio was not associated with disease stage and risk status in early stage differentiated thyroid cancers. Additional studies are needed for its importance in advanced differentiated thyroid cancers.

Systematic population-based identification of NTRK and RET fusion-positive thyroid cancers

Objective

The aim of the study was to identify patients with NTRK fusion-positive or RET fusion/mutation-positive thyroid cancers, who could benefit from neurotrophic tyrosine kinase receptor (NTRK) or receptor tyrosine kinase (RET) inhibitors.

Methods

Patients were identified in the Calgary prospective thyroid cancer database (N= 482). Patients were 'pre-screened' with clinically available MassARRAY® BRAF test, Colon Panel, Melanoma Panel, or ThyroSPEC™. Mutation-negative tumors were 'screened' for NTRK fusions and RET fusions/mutations with the Oncomine™ Comprehensive Assay v3 (OCAv3).

Results

A total of 86 patients were included in 1 of 2 separate analyses. Analysis A included 42 patients with radioactive iodine (RAI)-resistant distant metastases. After pre-screening, 20 BRAF and RAS mutation-negative patients underwent OCAv3 screening, resulting in the detection of 4 patients with NTRKfusions and 4 patients with RET fusions (8/20, 40% of analyzed patients). Analysis B included 44 patients, 42 with American Thyroid Association (ATA) high and intermediate risk of recurrence and 2 with medullary thyroid carcinoma. During pre-screening, 1 patient with an NTRK fusion, 1 patient with a RET fusion, and 30 patients with BRAF mutations were identified. The remaining 9 patients received OCAv3 screening, resulting in detection of 1 patient with an NTRKfusion and 1 with a RET fusion (4/11, 36% of analyzed patients).

Conclusions

Our findings indicate a higher rate of NTRK fusions and RETfusions in patients with thyroid cancer with RAI-resistant distant metastases and ATA high or intermediate risk of recurrence. This highlights the importance of early screening to enable intervention with a NTRK or RET inhibitor.

CircRNA casein kinase 1 gamma 1 (circ-CSNK1G1) plays carcinogenic effects in thyroid cancer by acting as miR-149-5p sponge and relieving the suppression of miR-149-5p on mitogen-activated protein kinase 1 (MAPK1)

BACKGROUND

The initiation and development of thyroid cancer may be associated with the deregulation of circular RNAs (circRNAs). The purpose of this work was to explore the role of circRNA casein kinase 1 gamma 1 (circ-CSNK1G1) in thyroid cancer.

METHODS

The expression of circ-CSNK1G1, miR-149-5p, and mitogen-activated protein kinase 1 (MAPK1) was concluded using quantitative real-time PCR (qPCR), and the expression of MAPK1 protein was detected by Western blot assay. Cell viability was monitored by CCK-8 assay. Cell proliferation was determined by colony formation assay and EdU assay. Cell apoptosis and cycle were checked by flow cytometry assay. Cell invasion was determined by transwell assay. The predicted binding relationship between miR-149-5p and circ-CSNK1G1 or MAPK1 was verified by dual-luciferase reporter assay. The role of circ-CSNK1G1 in vivo was determined by establishing animal models.

RESULTS

The present work discovered the upregulation of circ-CSNK1G1 in tumor tissues of thyroid cancer. In function, circ-CSNK1G1 knockdown inhibited proliferation, survival, and invasion in cancer cells, and tumor growth in mouse models. MiR-149-5p was a target of circ-CSNK1G1, and the anti-tumor effects of circ-CSNK1G1 knockdown were abolished by miR-149-5p downregulation. In addition, miR-149-5p directly targeted MAPK1, and miR-149-5p restoration-inhibited cell proliferation and invasion were recovered by MAPK1 overexpression.

CONCLUSION

Circ-CSNK1G1 acted as miR-149-5p to relieve the inhibition of miR-149-5p on MAPK1, thus promoting the malignant development of thyroid cancer.

Improving the prediction of persistent and recurrent differentiated thyroid cancer using the American Thyroid Association 2015 risk stratification system

PURPOSE

The 2015 American Thyroid Association risk stratification system (ATA RSS) is used in patients with differentiated thyroid carcinoma (DTC) to assess their risk of persistent/recurrent disease. Our aims were to validate the 2015 ATA RSS in a registry of DTC patients and to examine whether the addition of factors not included in it, such as pre-radioactive iodine therapy stimulated thyroglobulin (pre-RAI sTg), gender, and age could increase its predictive ability.

METHODS

We studied 403 patients with DTC, treated at a tertiary center from 1990 to 2018 and subjected to total thyroidectomy. All patients had received RAI therapy, except those with low-risk papillary microcarcinoma.

RESULTS

Of our patients, 81.9% were women and 91.1% had papillary thyroid carcinoma. After a median follow-up of 5.0 years, 53 cases of persistent and 21 cases of recurrent disease were recorded. The proportion of variance explained (PVE) regarding the outcome (presence or absence of recurrent/persistent disease) using the 2015 ATA RSS alone was 18.3% (persistence) and 16.9% (recurrence), increasing to 74.4% and 52.0%, respectively, when pre-RAI sTg was added to the logistic regression model. Gender and age were not associated with the disease outcome. In ROC analysis, pre-RAI sTg had a high predictive value for persistent (AUC 0.983, 95% CI 0.962-1.000) and recurrent disease (AUC 0.856, 95% CI 0.715-0.997). The optimal cut-offs and sensitivity, specificity, and positive and negative predictive value for pre-RAI sTg were the following: for persistence 12.75 ng/ml, 100%, 90.5%, 64%, and 100%, and for recurrence 8.05 ng/ml, 77.8%, 85.5%, 36.8%, and 97%.

CONCLUSIONS

The 2015 ATA RSS displayed moderate performance in predicting recurrent/persistent disease in patients with DTC, which improved with the inclusion of pre-RAI sTg values; pre-RAI sTg was an independent predictor of the disease outcome, with high negative prognostic value.

Clinical implications of age and excellent response to therapy in patients with high-risk differentiated thyroid carcinoma

BACKGROUND

Patients with American Thyroid Association (ATA) high-risk differentiated thyroid carcinoma (DTC) have poor clinical outcomes. This study aimed to evaluate the clinical implications of age and response to therapy classification in patients with ATA high-risk DTC.

DESIGN AND PATIENTS

This study included 222 patients with high-risk DTC who initially underwent therapy between 2000 and 2010 in a single tertiary center in Korea. We evaluated the prognostic parameters associated with progression-free survival (PFS) and disease-specific survival (DSS) with a focus on age and achieving an excellent response (ER).

RESULTS

During the median follow-up period of 11.3 years, disease progression was detected in 77 patients (34.7%), and disease-specific mortality was reported in 31 patients (14.0%). Older age (≥55 years) and not achieving ER (not-ER) were independent risk factors associated with PFS (age, p < .001; not-ER, p < .001) and DSS (age, p < .001; not-ER, p = .015). Of the 74 patients in the ER group, 7 (9.5%) displayed disease progression and 1 (1.4%) died from DTC. There were no significant differences in PFS and DSS according to age in the ER group. However, older patients had significantly worse PFS and DSS than younger patients in the not-ER group (p = .002 and p < .001, respectively).

CONCLUSIONS

Response to therapy classification is important for predicting PFS and DSS in patients with high-risk DTC. Patients in the ER group had a relatively good prognosis, but disease progression occurred in 9.5% of patients. Age was a key predictor of both PFS and DSS in high-risk patients who did not achieve ER.

Comparison of the abilities of staging and risk stratification systems to predict the long-term structural recurrence in patients with differentiated thyroid carcinoma after total thyroidectomy and radioactive iodine remnant ablation

Background

In patients with differentiated thyroid carcinoma (DTC), various staging and risk stratification systems have been applied to estimate long-term recurrence, which is a major issue during the postoperative follow-up period. However, the efficacy of these systems remains unclear in this context.

Methods

The present historical cohort study included 510 patients with DTC who underwent a total thyroidectomy followed by radioactive iodine (RAI) remnant ablation. Enrolled patients were categorized according to the 8^th edition of American Joint Committee on Cancer/Union for International Cancer Control (AJCC/UICC) Tumor Node Metastasis (TNM) staging system, the 2015 American Thyroid Association (ATA) initial risk stratification system, and the dynamic risk stratification (DRS) system. The ability of each system to predict long-term structural recurrence was compared using proportion of variance explained (PVE) by logistic regression models.

Results

The median follow-up period was 108 months. Structural recurrence occurred in 7.6% of the patients (n=39/510). Disease-free survival (DFS) curves of the patients within each category in the TNM staging system, the ATA initial risk stratification system, and the DRS system were significantly different (P<0.001). The PVE of the DRS system (20.7%) was higher than those of the TNM staging system and the ATA initial risk estimates.

Conclusions

The DRS system may effectively predict long-term structural recurrence and guide long-term management and follow-up strategies in patients with DTC undergoing total thyroidectomy and RAI remnant ablation.

miR-671-5p repressed progression of papillary thyroid carcinoma via TRIM14

The pivotal role of dysregulated miRNAs in development of papillary thyroid carcinoma has been emphasized in recent research. miR-671-5p was previously documented to function as a tumor suppressor. However, the role and mechanism of miR-671-5p in progression of papillary thyroid carcinoma remain to be further studied. Data from functional assays indicated that forced expression of miR-671-5p decreased cell viability, repressed cell proliferation, migration, and invasion in papillary thyroid carcinoma cells. In vivo study showed that miR-671-5p overexpression inhibited tumor growth, downregulated Ki67, and decreased tumor volume and weight. Tripartite motif containing 14 (TRIM14) was verified as downstream target of miR-671-5p. The expression of TRIM14 was suppressed by miR-671-5p in papillary thyroid carcinoma. Overexpression of TRIM14 increased cell viability, and promoted the proliferation, migration, and invasion of papillary thyroid carcinoma. Moreover, TRIM14 counteracted the suppressive effect of miR-671-5p overexpression on papillary thyroid carcinoma cell growth. In conclusion, miR-671-5p repressed progression of papillary thyroid carcinoma through downregulation of TRIM14, providing a promising target for therapy of papillary thyroid carcinoma.

Real-World Performance of the American Thyroid Association Risk Estimates in Predicting 1-Year Differentiated Thyroid Cancer Outcomes: A Prospective Multicenter Study of 2000 Patients

Background: One of the most widely used risk stratification systems for estimating individual patients' risk of persistent or recurrent differentiated thyroid cancer (DTC) is the American Thyroid Association (ATA) guidelines. The 2015 ATA version, which has increased the number of patients considered at low or intermediate risk, has been validated in several retrospective, single-center studies. The aims of this study were to evaluate the real-world performance of the 2015 ATA risk stratification system in predicting the response to treatment 12 months after the initial treatment and to determine the extent to which this performance is affected by the treatment center in which it is used. Methods: A prospective cohort of DTC patients collected by the Italian Thyroid Cancer Observatory web-based database was analyzed. We reviewed all records present in the database and selected consecutive cases that satisfied inclusion criteria: (i) histological diagnosis of DTC, with the exclusion of noninvasive follicular thyroid neoplasm with papillary-like nuclear features; (ii) complete data of the initial treatment and pathological features; and (iii) results of 1-year follow-up visit (6-18 months after the initial treatment), including all data needed to classify the estimated response to treatment. Results: The final cohort was composed of 2071 patients from 40 centers. The ATA risk of persistent/recurrent disease was classified as low in 1109 patients (53.6%), intermediate in 796 (38.4%), and high in 166 (8.0%). Structural incomplete responses were documented in only 86 (4.2%) patients: 1.5% in the low-risk, 5.7% in the intermediate-risk, and 14.5% in the high-risk group. The baseline ATA risk class proved to be a significant predictor of structural persistent disease, both for intermediate-risk (odds ratio [OR] 4.67; 95% confidence interval [CI] 2.59-8.43) and high-risk groups (OR 16.48; CI 7.87-34.5). Individual center did not significantly influence the prediction of the 1-year disease status. Conclusions: The ATA risk stratification system is a reliable predictor of short-term outcomes in patients with DTC in real-world clinical settings characterized by center heterogeneity in terms of size, location, level of care, local management strategies, and resource availability.

Course and Predictive Factors of Incomplete Response to Therapy in Low- and Intermediate-Risk Thyroid Cancer

Context

Controversy surrounds the extent and intensity of the management of American Thyroid Association (ATA) intermediate- and low-risk patients with differentiated thyroid cancer (DTC). Understanding the natural history and factors that predict outcome is important for properly tailoring the management of these patients.

Objective

This work aims to study the natural course and predictive factors of incomplete response to therapy in low- and intermediate-risk DTC.

Patients and Methods

We studied a cohort of 506 consecutive patients [418 women (82.6%) and 88 men (17.4%)] with low and intermediate risk with a median age of 35 years (interquartile range [IQR], 27-46 years). We analyzed the natural course and the predictive factors of biochemically or structurally incomplete response.

Results

Of 506 patients studied, 297 (58.7%) patients were in the low-risk group and 209 (41.3%) were in the intermediate-risk group. Over a median follow-up of 102 months (IQR, 66-130 months), 458 (90.5%) patients achieved an excellent response, 17 (3.4%) had a biochemically incomplete status, and 31 (6.1%) had a structurally incomplete status. In univariable and multivariable analyses, age (≥ 33 years) (P < .0001, odds ratio 1.06 [1.04-1.08]) and lateral lymph node metastasis (LNM; P < .0001, odds ratio 3.2 [1.7-5.9]) were strong predictive factors for biochemically and structurally incomplete response to therapy. Sex, tumor size, multifocality, extrathyroidal extension, and lymphovascular invasion did not predict incomplete response to therapy.

Conclusions

Patients with low- and intermediate-risk DTC have favorable outcomes. Age and lateral LNM are strong predictors of an incomplete response to therapy. This suggests that older patients and those with LNM should be managed and followed up more actively than younger patients and those without LNM.

An impact of microscopic positive margin on incomplete response after I-131 treatment in differentiated thyroid cancer

OBJECTIVE

To find an impact of microscopic positive margin on incomplete response after initial I-131 therapy in differentiated thyroid cancer.

METHODS

We retrospectively recruited patients with differentiated thyroid cancer who underwent total thyroidectomy and received the first dose of radioiodine during January 2014-February 2018. Patients with grossly incomplete tumor resection or distant metastasis at the time of radioiodine therapy were excluded. Thyroid specimens were re-evaluated by one pathologist who was blinded to clinical information to determine microscopic margin status. Treatment response was evaluated at 6-12 months after therapy and was categorized according to the 2015 American Thyroid Association guidelines. Univariable and multivariable analyses were used to find an association between microscopic positive margin and incomplete response.

RESULTS

A total of 101 patients (78 females; mean age 50.3 years) were enrolled. Ninety-four patients (93.1%) had papillary thyroid carcinoma. Microscopic positive margin was found in 27 patients (26.7%). After the median follow-up time of 10.3 months, incomplete response was observed in 13 patients (48.5%) and 17 patients (23.0%) with positive and negative margins, respectively. Multivariable analysis showed a significant association between microscopic positive margin and incomplete response after adjusting for tumor size, ETE, and cervical lymph node metastasis with adjusted odds ratio of 3.04 (95% CI 1.05-8.75, p value = 0.04). Moreover, after adding pre-ablative Tg as a covariate in 69 patients with negative TgAb, positive margin had a trend toward being associated with incomplete response with adjusted odds ratio of 3.43 (95% CI 0.73-16.07, p value = 0.118).

CONCLUSIONS

Microscopic positive margin was found to be significantly associated with incomplete response after I-131 therapy in patients with differentiated thyroid cancer after adjusting for tumor size, ETE, and cervical lymph node metastasis and also had a trend toward being associated with incomplete response after adjusting for pre-ablative Tg.

Predictors of recurrence after total thyroidectomy plus neck dissection and radioactive iodine ablation for high-risk papillary thyroid carcinoma

BACKGROUND

American Thyroid Association (ATA) proposed management guidelines for differentiated thyroid cancer, including a three-tiered risk stratification system for structural recurrence. This study aimed to compare the various 2015 ATA criteria for the strength of association with the recurrence of high-risk papillary thyroid carcinoma (PTC).

STUDY DESIGN

This study included 545 consecutive patients who underwent total thyroidectomy plus neck dissection and radioactive iodine ablation (RAI) for previously untreated high-risk PTC. The association of recurrence-free survival (RFS) with clinicopathological factors was evaluated by univariate and multivariate Cox proportional hazard regression analyses.

RESULTS

During a follow-up median period of 89 months, 90 (16.5%) patients had any-site recurrence. Of the high-risk factors, high stimulated thyroglobulin (sTg) level and >3-cm sized lymph nodes (LNs) were significantly associated with recurrence (all P < .005). Sex, tumor size, lymphovascular invasion, multifocality, number of positive LNs, extranodal extension, T and N classifications, and overall tumor-node-metastasis stage were also significantly associated with recurrence (all P < .05). In multivariate analyses, high sTg level [adjusted hazard ratio (HR) = 7.18] and N1b (adjusted HR = 3.27) were independent factors predictive of recurrence (all P ≤ .001).

CONCLUSIONS

Postoperative high serum sTg level might be the most important predictor of PTC recurrence after total thyroidectomy plus neck dissection and RAI.

The benefits of radioactive iodine ablation for patients with intermediate-risk papillary thyroid cancer

BACKGROUND

The beneficial effects of radioactive iodine (RAI) ablation for intermediate-risk papillary thyroid cancer (PTC) patients are still controversial.

MATERIALS AND METHODS

To determine the impact of RAI therapy on disease-specific survival (DSS) in patients with intermediate-risk PTC, we retrospectively analyzed the data of 23107 intermediate-risk PTC patients who underwent primary thyroidectomy with or without RAI in the Surveillance, Epidemiology, and End Results (SEER) database.

RESULTS

RAI therapy was significantly associated with improved DSS (adjusted HR = 0.65, P = 0.017) in intermediate-risk PTC patients after multivariate adjusting for clinicopathological characteristics. However, subgroup analyses demonstrated that RAI ablation was only associated with improved DSS in patients with male gender (adjusted HR = 0.47, P = 0.005), age ≥ 45 years (adjusted HR = 0.34, P < 0.001) and tumor size > 20 mm (adjusted HR = 0.58, P = 0.007).

CONCLUSION

RAI decision-making should be considered on an individual basis rather than "one size fits all" in intermediate-risk PTC patients; only patients with male gender, age ≥ 45 years, and tumor size > 20 mm may benefit from RAI therapy.

Unexplained Hyperthyroglobulinemia in Differentiated Thyroid Cancer Patients as an Indication for Radioiodine Adjuvant Therapy: A Prospective Multicenter Study

The management for totally thyroidectomized differentiated thyroid cancer (TT-DTC) patients with unexplained hyperthyroglobulinemia remains indeterminate because of evidence scarcity. This multicenter study aimed at prospectively evaluating the response to radioiodine (¹³¹I) adjuvant therapy (RAT) and its potential role in risk stratification and causal clarification. Methods: TT-DTC patients with stimulated serum thyroglobulin levels greater than 10 ng/mL but no structurally evident disease were consecutively enrolled in 5 tertiary-care institutions. After the administration of 5.55 GBq of ¹³¹I, the risk of persistent, recurrent, or metastatic differentiated thyroid cancer (prmDTC) was compared with that before RAT. The causes of hyperthyroglobulinemia were explored-and the response to RAT assessed-6-12 mo after RAT. The change in suppressed thyroglobulin level was reported. Results: A cohort of 254 subjects with a median stimulated thyroglobulin level of 27.1 ng/mL was enrolled for the analyses. Immediately after RAT, low, intermediate, and high risk were identified in 5.9%, 88.6%, and 5.5% patients, respectively, with no significant difference in risk stratification compared with that before RAT (P = 0.952). During the follow-up (median, 10.6 mo), hyperthyroglobulinemia was ultimately attributed to a thyroid remnant, biochemical disease, and structural or functional disease in 17.3%, 54.3%, and 28.4% of subjects, respectively. In addition, responses that were excellent, indeterminate, biochemically incomplete, and structurally or functionally incomplete were achieved in 18.1%, 27.2%, 36.2%, and 18.5% of patients, respectively. Notably, the distribution for either cause of hyperthyroglobulinemia or response to RAT was comparable among the 3 postoperative risk groups. Suppressed thyroglobulin levels in patients who merely received RAT declined significantly over time. Conclusion: Our study demonstrated that over 90% of TT-DTC patients with unexplained hyperthyroglobulinemia are stratified as being at intermediate to high risk, and RAT using 5.55 GBq of ¹³¹I reveals biochemical, functional, or structural disease and yields a non-structurally or -functionally incomplete response in more than 80% patients, suggesting that TT-DTC patients with unexplained hyperthyroglobulinemia are explicit candidates for RAT.

Evaluation of the 2015 ATA Guidelines in Patients With Distant Metastatic Differentiated Thyroid Cancer

CONTEXT

Current American Thyroid Association (ATA) Management Guidelines for the treatment of differentiated thyroid cancer (DTC) stratify patients to decide on additional radioiodine (RAI) therapy after surgery, and to predict recurring/persisting disease. However, studies evaluating the detection of distant metastases and how these guidelines perform in patients with distant metastases are scarce.

OBJECTIVE

To evaluate the 2015 ATA Guidelines in DTC patients with respect to 1) the detection of distant metastases, and 2) the accuracy of its Risk Stratification System in patients with distant metastases.

PATIENTS AND MAIN OUTCOME MEASURES

We retrospectively included 83 DTC patients who were diagnosed with distant metastases around the time of initial therapy, and a control population of 472 patients (312 low-risk, 160 intermediate-risk) who did not have a routine indication for RAI therapy. We used the control group to assess the percentage of distant metastases that would have been missed if no RAI therapy was given.

RESULTS

Two hundred forty-six patients had no routine indication for RAI therapy of which 4 (1.6%) had distant metastases. Furthermore, among the 83 patients with distant metastases, 14 patients (17%) had excellent response, while 55 (67%) had structural disease after a median follow-up of 62 months. None of the 14 patients that achieved an excellent response had a recurrence.

CONCLUSIONS

In patients without a routine indication for RAI therapy according to the 2015 ATA Guidelines, distant metastases would initially have been missed in 1.6% of the patients. Furthermore, in patients with distant metastases upon diagnosis, the 2015 ATA Guidelines are an excellent predictor of both persistent disease and recurrence.

The Clinicopathological Features of Papillary Thyroid Carcinoma Patients with Positive Hepatitis B Surface Antigen

BACKGROUND

Hepatitis B virus infection has been reported to be associated with some kinds of cancer. The aim of this study was to investigate clinicopathological features of papillary thyroid carcinoma (PTC) patients with positive hepatitis B surface antigen (HBsAg).

MATERIALS AND METHODS

A total of 569 PTC patients were analyzed retrospectively in this study. The relationships of HBsAg with clinicopathologic features of PTC were analyzed by univariate analysis. The relationships of central lymph node metastasis (CLNM) with clinicopathological features of PTC were analyzed by univariate and multivariate logistic regression analysis.

RESULTS

The incidence of CLNM in PTC with positive HBsAg was higher than that in PTC with negative HBsAg (71.4 vs. 60.0%, p = 0.047). Univariate analysis showed that positive HBsAg was significantly associated with bilateral tumors (p = 0.043) and lymph node metastasis (LNM) (p = 0.047) in PTC patients. In addition, the incidence of CLNM in patients with PTC was 61.7% (351 of 569 cases). Univariate analysis showed that CLNM of patients with PTC was significantly associated with positive HBsAg (p = 0.047). Multivariate logistic regression analysis revealed that positive HBsAg (p = 0.038) was an independent predictor of CLNM in patients with PTC.

CONCLUSIONS

The incidence of CLNM in PTC patients with positive HBsAg was significantly higher than that of patients with negative HBsAg. Positive HBsAg was correlated with LNM and bilateral tumors. In addition to gender, age <45 years, tumor size >2 cm, and lateral LNM, positive HBsAg was also an independent predictor of CLNM in PTC patients.

Treatment of Differentiated Thyroid Carcinomas

Differentiated thyroid cancer (DTC) is the most common thyroid cancer and is frequently encountered in clinical practice. The incidence of DTC has increased significantly over the past three decades. Surgical resection, radioactive iodine (RAI), and levothyroxine suppression therapy remain the primary modalities for DTC treatment. Active surveillance for low-risk thyroid cancer may be an alternative to immediate surgery for appropriately selected patients. Patient characteristics influence treatment selection and intensity. In the subset of patients with progressive distant metastatic disease, not amenable to treatment with surgery or RAI, novel agents, including targeted therapies and immunotherapy, should be considered.

Performance of ATA Risk Stratification Systems, Response to Therapy, and Outcome in an Indian Cohort of Differentiated Thyroid Carcinoma Patients: A Retrospective Study

INTRODUCTION

For better individualized management of differentiated thyroid carcinoma (DTC), ATA risk stratification systems (RSS) of 2009 and 2015 as well as a response to therapy re-classification (ATA RTR-2015) are used worldwide for assessing risk of recurrence. But there are no validation studies of these systems from the Indian subcontinent.

OBJECTIVES

To compare ATA RSS-2009, ATA RSS-2015, and ATA RTR-2015 for their accuracy in predicting outcome in DTC patients.

METHODS

This was a retrospective review of 236 adult patients with DTC >1 cm attending the Thyroid Cancer Clinic at our Institute who had undergone total thyroidectomy and radioactive iodine ablation. Initial risk stratification using ATA RSS-2009 and RSS-2015, clinical response at 1 year and outcome at last follow-up measured by clinical end points were collected and analyzed.

RESULTS

ATA RSS-2015 could not be applied to this cohort due to lack of histopathology details. While 77.3% of low-risk ATA RSS-2009 had disease-free status (NED, no evidence of disease) on follow-up, 96.1% of patients, in excellent response in ATA RTR-2015, showed NED. Whereas persistent structural disease was predicted by the high-risk group in ATA RSS-2009 (61.9%) and by the incomplete structural response group in ATA RTR-2015 (57.1%) equally well, the best predictor for NED at 1 year in this cohort was ATA RTR-2015 (p < 0.001).

CONCLUSION

This study found that both ATA RSS-2009 and ATA RTR-2015 are reliable in predicting outcome in DTC patients after initial treatment. However, the response to initial therapy at 1 year predicted outcome more accurately than the initial risk status.

Assessment of the impact of 2015 American Thyroid Association guidelines in management of differentiated thyroid cancer patients

The 2015 American Thyroid Association (ATA) guideline have suggested modifications in the risk stratification (RS) for differentiated thyroid cancer (DTC) patients, introduced the concept of dynamic risk stratification (DRS) and redefined the role of radioactive iodine (RAI) in treatment algorithm. The aim of this retrospective audit was to assess the practical implications of these modifications in management of DTC.

METHODS

A total of 138 DTC patients were stratified according to ATA 2009 and 2015 guidelines into low (LR), intermediate (IR) and high (HR) risk groups. Change in RS and in intention of RAI use was calculated. Deviation in administered RAI dosage from the guidelines was assessed. 1-year follow-up data was audited to assess how the DRS modified the initial risk estimate.

RESULTS

A total of 11.6% of patients changed their RS categories in 2015 guidelines. A total of 10.1% got upstaged to HR, and 1.4% got downstaged to LR. In 2.17% of patients' intention of RAI use changed to remnant ablation from adjuvant therapy and 65% of the LR patients won't require any RAI therapy. A total of 26.7% of patients had received significantly more RAI dosage according to ATA 2015. At 1-year follow-up according to DRS 84% of LR, 75% of IR and 44% of HR patients showed excellent response (ER).

CONCLUSION

More patients changed RS to HR than to LR. Intention of RAI use changed in only a small number of patients. Significantly higher dosage of RAI is being administered to patients in current practice. The effect of DRS in modifying the initial RS was most prominent in IR, with most showing ER to initial therapy.

The prognostic value of the lymphocyte-to-monocyte ratio for high-risk papillary thyroid carcinoma

Background and Aims

The prognosis of papillary thyroid carcinoma (PTC) is highly variable, even for high-risk cases. The predictive and prognostic role of the lymphocyte-to-monocyte ratio (LMR) has been reported in other cancers. The aim of our present study was to explore the value of LMR prognostic prediction in high-risk PTC patients.

Patients and Methods

Two hundred and twenty-four PTC high-risk cases at West China Hospital were randomized into a training set (112 cases) and testing set (112 cases), while 48 cases in Shang Jin Nan Fu Hospital were included as the external validation set.

Results

A lower preoperative LMR correlated with larger tumor size, advanced N and M stages, and an increased number of multiple PTC cases in the training, testing, and validation sets (all P<0.05 in the three sets). Patients with a high LMR exhibited significantly improved overall and PTC-free survival compared with those of patients with a low LMR in the training, testing, validation, and combined sets (all P<0.05 in the individual and combined sets). Moreover, multivariate analyses identified the LMR as an independent prognostic factor for overall and PTC-free survival. The nomograms for predicting the 5-year mortality and PTC recurrence were developed based on the risk factors in the training set and validated in the independent testing and validation sets.

Conclusion

The preoperative LMR was identified as an independent prognostic factor that could be incorporated into the two nomograms with other risk factors to predict overall survival and PTC-free survival for individual patients.

Evaluating the 2015 American Thyroid Association Risk Stratification System in High-Risk Papillary and Follicular Thyroid Cancer Patients

Background: The 2015 American Thyroid Association (ATA) Risk Stratification System for differentiated thyroid cancer (DTC) is designed to predict recurring/persisting disease but not survival. Earlier studies evaluating this system evaluated the 2009 edition, comprised a low number of patients with ATA high-risk, had low numbers of patients with follicular thyroid cancer (FTC), or did not distinguish between papillary and FTC. Therefore, we evaluated the prognostic value of the 2015 ATA Risk Stratification System in a large population of high-risk thyroid cancer patients, which included a substantial proportion of FTC patients. Methods: We retrospectively studied adult patients with DTC who were diagnosed and/or treated at a Dutch university hospital between January 2002 and December 2015. All patients fulfilled the 2015 ATA high-risk criteria. Overall survival and disease-specific survival (DSS) were analyzed using the Kaplan-Meier method. Logistic regression and Cox proportional hazards models were used to estimate the effects of DTC subtype and ATA high-risk criteria on response to therapy, recurrence, as well as survival. Results: We included 236 patients with high-risk DTC (32% FTC) with a mean age of 56 years. Median follow-up was 6 years. At final follow-up, 69 patients (29%) had excellent response, while 120 (51%) had structural disease. All high-risk criteria, except large pathologic lymph nodes, were inversely related to excellent response and positively related to structural disease at final follow-up. During follow-up, 14% of the 79 patients who achieved excellent response developed a recurrence. Finally, 10-year DSS was much higher in the initial excellent response than in the initial structural disease group (100% vs. 61%, respectively). Conclusions: In a population of high-risk DTC patients harboring a large subset of FTC patients, the 2015 ATA Risk Stratification System is not only an excellent predictor of persisting disease but also of survival. As much as 14% of the high-risk patients who had an excellent response upon dynamic risk stratification experienced a recurrence during follow-up. Clinicians should thus be aware of the relatively high recurrence risk in these patients, even after an excellent response to therapy.

In properly selected patients with differentiated thyroid cancer, antithyroglobulin antibodies decline after thyroidectomy and their sole presence should not be an indication for radioiodine ablation

OBJECTIVE

Our objective was to evaluate the trend of antithyroglobulin antibodies (TgAb) during follow-up of patients with differentiated thyroid cancer (DTC) treated without RAI, as well as their role in the risk of recurrence.

SUBJECTS AND METHODS

This was a prospective, descriptive study. A total of 152 consecutive patients with DTC treated in a single institution undergoing total thyroidectomy without RAI and followed for a median of 2.3 years (0.5-10.3) were divided in two groups: TgAb(-) (n = 111) and TgAb(+) (n = 41). Patients were classified according to AJCC 7th and 8th editions, as well as to their risk of recurrence and response to treatment categories.

RESULTS

Both groups, TgAb(-) and TgAb(+), were similar regarding patient and tumor characteristics. At the end of follow-up, 90 (59.2%), 57 (37.5%), 3 (2%) and 2 (1.3%) patients achieved excellent, indeterminate, biochemically incomplete and structurally incomplete response, respectively. The risk of structural recurrence was similar in both groups (TgAb[-] 0.9% vs. TgAb[+] 2.4%, p = 0.46). In the TgAb(+) group, TgAb became negative in 10 (24.4%), decreased ≥ 50% without negativization in 25 (60.9%), decreased < 50% in 4 (9.8%) and remained stable or increased in 2 (4.9%) cases. The only incomplete structural response had increasing TgAb during follow-up.

CONCLUSIONS

In properly selected patients with DTC, TgAb concentration immediately after total thyroidectomy should not mandate RAI ablation, and their trend during follow-up may impact the risk of recurrence.

Risk Stratification in Differentiated Thyroid Cancer: From Detection to Final Follow-up

CONTEXT

Modern management of differentiated thyroid cancer requires individualized care plans which tailor the intensity of therapy and follow-up to the estimated risks of recurrence and disease-specific mortality.

EVIDENCE ACQUISITION

This summary is based on the authors' knowledge and extensive clinical experience supplemented by review of published review articles, thyroid cancer management guidelines, published staging systems, and original articles identified through a PubMed search which included terms such as risk stratification, staging, clinical outcomes, and differentiated thyroid cancer.

EVIDENCE SYNTHESIS

In the past, risk stratification in differentiated thyroid cancer usually referred to a static estimate of disease-specific mortality that was based on a small set of clinicopathological features available within a few weeks of completing initial therapy (thyroidectomy with or without radioactive iodine). Today, risk stratification is a dynamic, active process used to predict the appropriateness for minimalistic initial therapy, disease-specific mortality, risk of recurrence, and the most likely response to initial therapy. Rather than being a static prediction available only after initial therapy, modern risk stratification is a dynamic, iterative process that begins as soon as a suspicious nodule is detected and continues through final follow-up.

CONCLUSIONS

Dynamic risk assessment should be used to guide all aspects of thyroid cancer management, beginning before a definitive diagnosis is made and continuing through the final follow-up visit.

MicroRNA-101 Targets CXCL12-Mediated Akt and Snail Signaling Pathways to Inhibit Cellular Proliferation and Invasion in Papillary Thyroid Carcinoma

Escalating evidence suggests that microRNA-101 (miR-101) is implicated in the development and progression of various cancers, including papillary thyroid carcinoma (PTC). However, the biological function and molecular mechanisms of miR-101 in PTC are still unclear. In this study, we demonstrated that miR-101 expression was significantly decreased in PTC tissues and cell lines. Clinically, a low level of miR-101 was positively associated with advanced histological stages and lymph node and distant metastases. The expression of CXCL12 was negatively correlated with miR-101 level in PTC. CXCL12 was validated as a direct target of miR-101 in PTC cells. Functional experiments proved that miR-101 markedly reduced the proliferation, apoptosis escape, migration, and invasion of PTC cells. Moreover, CXCL12 restoration rescued the suppressive effects of miR-101 on PTC cells by activating Akt- and EMT-associated signaling pathways. Overall, miR-101 exerts oncostatic effects on PTC by downregulating CXCL12 and repressing its downstream Akt and Snail signaling pathways, suggesting that miR-101/CXCL12/Akt or Snail axis may serve as a potential therapeutic target for PTC.

Clinical Assessment and Risk Stratification in Differentiated Thyroid Cancer

Thyroid cancer management is rapidly evolving to a personalized management approach. Risk stratification systems are designed to assist in personalized management. Differentiating patients who may benefit from aggressive therapy and intense follow-up as opposed to those who can be successfully treated with minimalized initial management options and follow-up is crucial to the development of the right treatment plan for the right patient in order to optimize initial therapy and follow-up testing. This article aims to describe and discuss the risk stratification systems currently recommended for differentiated thyroid cancer.

Time to Separate Persistent From Recurrent Differentiated Thyroid Cancer: Different Conditions With Different Outcomes

CONTEXT

Differentiated thyroid cancer (DTC) has an excellent prognosis, but up to 20% of patients with DTC have disease events after initial treatment, indistinctly defined as persistent/recurrent disease.

OBJECTIVE

To evaluate the prevalence and outcome of "recurrent" disease (relapse after being 12 months disease-free) compared with "persistent" disease (present ab initio since diagnosis).

DESIGN

Retrospective analysis of persistent/recurrent disease in patients with DTC (1990 to 2016) with 6.5 years of mean follow-up.

SETTING

Tertiary referral center for thyroid cancer.

PATIENTS

In total, 4292 patients all underwent surgery ± 131I treatment of DTC.

MAIN OUTCOME MEASURES

DTC cure of disease persistence or recurrence.

RESULTS

A total of 639 of 4292 (14.9%) patients had disease events after initial treatment, most (498/639, 78%) with persistent disease and 141 (22%) with recurrent disease. Relative to patients with recurrent disease, patients with persistent disease were significantly older (mean age 46.9 vs 45.7 years) and with a lower female to male ratio (1.9/1 vs 4.8/1). Moreover, in this group, structured disease was more frequent (65.7% vs 41.1%), and more important, distant metastases were significantly more frequent (38.4% vs 17.0%). At multivariate analysis, male sex (OR = 1.7), age (OR = 1.02), follicular histotype (OR = 1.5), T status (T3; OR = 3), and N status (N1b; OR = 7.7) were independently associated with persistent disease. Only the N status was associated with recurrent disease (N1b; OR = 2.5).

CONCLUSIONS

In patients with DTC not cured after initial treatment, persistent disease is more common and has a worse outcome than recurrent disease. Postoperative status evaluated during first-year follow-up may have important clinical implications for planning tailored treatment strategies and long-term follow-up procedures.

Total thyroidectomy versus lobectomy for intermediate-risk papillary thyroid carcinoma: A single-institution matched-pair analysis

BACKGROUND

Total thyroidectomy (TT) is recommended by guidelines for intermediate-risk papillary thyroid carcinoma (PTC) but its survival advantage over lobectomy has not been proven. The aim of this study was to examine the association between the extent of surgery and the clinical outcome of patients with intermediate-risk PTC.

METHODS

Adult patients with PTC in the institutional database from 1996 to 2008 were retrospectively reviewed. Intermediate-risk patients were defined according to the 2015 American Thyroid Association (ATA) guidelines. Patients who underwent TT and patients who underwent lobectomy were then matched according to individual risk factors. Survival analysis was performed within the two paired groups, focusing on recurrence-free survival (RFS) and disease-specific survival (DSS) rates.

RESULTS

Among 4230 PTC patients, 1087 intermediate-risk patients were included, in total 341 pairs were matched based on sex, age, primary size, clinical nodes (cN), extrathyroidal extension (ETE), pathological lateral neck metastasis (pN1b) and lymph node ratio (LNR). For these paired cases, with a median follow-up of 125 months (46-192), the lobectomy and TT groups were similar with respect to both 10-year RFS rate (77.4% vs 80.2%, log rank = 0.244, p = 0.622) and DSS rate (97.2% vs 98.4%, log rank = 0.351, p = 0.554). When excluding pairs of cases (62 pairs) who received radioiodine ablation (RAI), survival results were also similar in lobectomy and TT groups with respect to 10-year RFS rate (81.2% vs 83.1%, log rank = 0.63, p = 0.42) and DSS rate (97.3% vs 98.1%, log rank = 0.95, p = 0.33).

CONCLUSIONS

For intermediate-risk PTC, no advantages of TT over lobectomy were found with respect to RFS rate or DSS rate.

Dynamic Risk Stratification in the Follow-Up of Children and Adolescents with Differentiated Thyroid Cancer

BACKGROUND

Risk stratification for persistent disease is an important step in pediatric differentiated thyroid cancer (DTC) management. The dynamic risk stratification (DRS) is a well validated system for adults, but not yet for children and adolescents. This study evaluated the DRS as well as other prognostic factors in pediatric DTC.

METHODS

Patients aged ≤18 years from four DTC tertiary teaching hospitals in Southern Brazil were included. Clinical characteristics were systematically retrieved, and all patients were classified according to the risk-stratification system of the 2015 American Thyroid Association pediatric DTC guidelines (ATA risk) and according to DRS (excellent, indeterminate, biochemical, or structural incomplete responses). Disease status was evaluated after initial therapy and at last follow-up visit.

RESULTS

Sixty-six patients aged 14.5 ± 3.0 years were studied of whom 54 (81.8%) were girls and 62 (93.9%) had papillary thyroid carcinomas. Tumor size was 2.3 cm (P25-75 1.6-3.5); 41 (63.1%) had cervical and 18 (27.7%) distant metastasis at diagnosis. All patients underwent total thyroidectomy, and 63 (95.5%) received radioiodine. Patients were classified according to DRS after initial therapy (n = 63) as follows: 21 (33%) excellent, 13 (21%) indeterminate, 6 (9%) biochemical, and 23 (37%) structural incomplete responses. Notably, after six years (P25-75 2.7-10.0), most patients remained in the same category. Interestingly, the cutoff analysis of stimulated postoperative thyroglobulin (sPOTg) through receiver operating characteristic curve showed that the value of 37.8 ng/mL showed 81% sensitivity and 100% specificity to predict an excellent response. Prognostic factors associated with persistent disease in the univariate analysis were TNM, ATA risk, DRS, and sPOTg.

CONCLUSION

DRS after initial therapy and sPOTg are strong predictors of disease outcome and might be helpful for defining follow-up strategies in pediatric DTC.

Comparison of short-term oncologic outcome of robotic thyroid surgery using dynamic risk stratification: A propensity score-matched comparison study

BACKGROUND

The long-term oncologic outcome of robotic surgery for thyroid cancer is not well established. The aim of this study was to predict the long-term oncologic outcome of robotic surgery by using dynamic risk stratification in classic papillary thyroid carcinoma.

METHODS

A total of 444 propensity score-matched pairs of patients with papillary thyroid carcinoma treated with robotic surgery and conventional open surgery were classified into 4 response-to-therapy categories. The results were compared between the robotic surgery and open surgery groups.

RESULTS

The median follow-up duration was 60 months. After propensity score matching, the robotic surgery group showed less extensive thyroid surgery and lymph node dissection and a higher proportion of patients who underwent radioactive iodine remnant ablation than the open surgery group; however, the dynamic risk stratification did not differ between the 2 groups (P = .086).

CONCLUSION

The long-term oncologic outcome of robotic surgery is expected to be comparable with that of open surgery based on the dynamic risk stratification.

Dynamic risk stratification in papillary thyroid carcinoma measuring 1 to 4 cm

BACKGROUND AND OBJECTIVES

This study aimed to validate the dynamic risk stratification (DRS) system, evaluate its correlation with structural recurrence, and assess the clinicopathological risk factors associated with a nonexcellent response to initial therapy in patients with papillary thyroid cancer (PTC) measuring 1 to 4 cm.

METHODS

A total of 762 patients with classic PTC measuring 1 to 4 cm were classified into four categories based on their response to initial therapy 2 years postoperatively.

RESULTS

Structural recurrent disease occurred in 4.7%, 17.1%, 48.4%, and 83.9% of patients with excellent, indeterminate, biochemically incomplete, and structurally incomplete responses, respectively, at the time of the last follow-up. The response to initial therapy in the DRS was one of the independent risk factors for structural recurrence. The disease-free survival curves of patients with different responses showed significant differences (P < 0.001). Extensive extrathyroidal extension, lymph node (LN) metastasis, number of metastatic LNs greater than 2.0, metastatic LN ratio greater than 0.22, and extranodal extension were independent risk factors for nonexcellent response to initial therapy.

CONCLUSIONS

DRS can be a useful tool in predicting structural recurrence and guiding postoperative management and follow-up strategies in patients with PTC measuring 1 to 4 cm.