LONG-TERM OUTCOMES AND PROGNOSTIC FACTORS IN PATIENTS WITH DIFFERENTIATED THYROID CANCER AND DISTANT METASTASES

The potential role of reprogrammed glucose metabolism: an emerging actionable codependent target in thyroid cancer

Although the incidence of thyroid cancer is increasing year by year, most patients, especially those with differentiated thyroid cancer, can usually be cured with surgery, radioactive iodine, and thyroid-stimulating hormone suppression. However, treatment options for patients with poorly differentiated thyroid cancers or radioiodine-refractory thyroid cancer have historically been limited. Altered energy metabolism is one of the hallmarks of cancer and a well-documented feature in thyroid cancer. In a hypoxic environment with extreme nutrient deficiencies resulting from uncontrolled growth, thyroid cancer cells utilize "metabolic reprogramming" to satisfy their energy demand and support malignant behaviors such as metastasis. This review summarizes past and recent advances in our understanding of the reprogramming of glucose metabolism in thyroid cancer cells, which we expect will yield new therapeutic approaches for patients with special pathological types of thyroid cancer by targeting reprogrammed glucose metabolism.

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.

Metastatic differentiated thyroid cancer: worst prognosis in patients with metachronous metastases

PURPOSE

To describe the overall survival and progression-free survival in patients diagnosed with differentiated thyroid carcinoma with synchronous and metachronous metastatic involvement.

MATERIALS AND METHODS

A retrospective cohort study was conducted with 101 patients with differentiated thyroid cancer (DTC) who had metastatic involvement at diagnosis or during follow-up, who were treated at the National Cancer Institute between January 1, 2010 and December 31 of 2015.

RESULTS

81 patients (80.2%) were women and the mean age at diagnosis was 49 years (12-80). Synchronous metastases were detected in 54.5% of patients and metachronous metastasis was diagnosed in 45.5% of patients, in whom the mean time between initial diagnosis and the finding of distant metastases was 5 years. Pulmonary involvement occurred in almost all patients, with ¹³¹I uptake in 58% of synchronous metastases and in 21% of metachronous. There were 10 events in the patients with ¹³¹I-avid metastases with a median time to progression that was not reached, and there were 23 events in patients with ¹³¹I-refractory metastases with a median time to progression of 96 months; The median time to progression was significantly longer in patients with synchronous metastases compared to those with metachronous metastases (Not reached vs 95 months, P = 0.017) The 5-year overall survival rate was 95% to the entire cohort.

CONCLUSIONS

The present study contributes to the expansion of the knowledge about this clinical course of DTC with the finding of a worst prognosis in patients with metachronous metastases.

Predicting 18F-FDG SUVs of metastatic pulmonary nodes from CT images in patients with differentiated thyroid cancer by using a convolutional neural network

Purpose

The aim of this study was to predict standard uptake values (SUVs) from computed tomography (CT) images of patients with lung metastases from differentiated thyroid cancer (DTC-LM).

Methods

We proposed a novel SUVs prediction model using 18-layer Residual Network for generating SUVmax, SUVmean, SUVmin of metastatic pulmonary nodes from CT images of patients with DTC-LM. Nuclear medicine specialists outlined the metastatic pulmonary as primary set. The best model parameters were obtained after five-fold cross-validation on the training and validation set, further evaluated in independent test set. Mean absolute error (MAE), mean squared error (MSE), and mean relative error (MRE) were used to assess the performance of regression task. Specificity, sensitivity, F1 score, positive predictive value, negative predictive value and accuracy were used for classification task. The correlation between predicted and actual SUVs was analyzed.

Results

A total of 3407 nodes from 74 patients with DTC-LM were collected in this study. On the independent test set, the average MAE, MSE and MRE was 0.3843, 1.0133, 0.3491 respectively, and the accuracy was 88.26%. Our proposed model achieved high metric scores (MAE=0.3843, MSE=1.0113, MRE=34.91%) compared with other backbones. The predicted SUVmax (R^{2 =} 0.8987), SUVmean (R^{2 =} 0.8346), SUVmin (R^{2 =} 0.7373) were all significantly correlated with actual SUVs.

Conclusion

The novel approach proposed in this study provides new ideas for the application of predicting SUVs for metastatic pulmonary nodes in DTC patients.

Active surveillance in differentiated thyroid cancer: a strategy applicable to all treatment categories response

Currently, the differentiated thyroid cancer (DTC) management is shifted toward a tailored approach based on the estimated risks of recurrence and disease-specific mortality. While the current recommendations on the management of metastatic and progressive DTC are clear and unambiguous, the management of slowly progressive or indeterminate disease varies according to different centers and different physicians. In this context, active surveillance (AS) becomes the main tool for clinicians, allowing them to plan a personalized therapeutic strategy, based on the risk of an unfavorable prognosis, and to avoid unnecessary treatment. This review analyzes the main possible scenarios in treated DTC patients who could take advantage of AS.

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

Background

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

Method

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

Results

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

Conclusions

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

Systematic review registration

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

A Retrospective Cohort Study with Validation of Predictors of Differentiated Thyroid Cancer Outcomes

Background: The goal of radioactive iodine (RAI) in differentiated thyroid cancer (DTC) is to treat metastasis and reduce recurrence risk. International guidelines provide broad risk stratification to aid treatment decisions, but a more nuanced approach to individualize care is warranted. We developed a predictive risk model for DTC. Methods: We performed a retrospective multivariable analysis of 899 patients who received RAI after thyroidectomy at a quaternary center in Australia between 2008 and 2016. Collected data included age, gender, histology, stimulated thyroglobulin (sTg), and 8th American Joint Committee Cancer (AJCC) staging. The ATA Modified Initial Risk (ATA) was calculated retrospectively. Recurrence was defined as clinically significant progression requiring either surgical intervention or administration of a second activity of RAI. Synchronous metastasis was defined as distant metastasis (i.e., outside of the neck) that was present at the time of diagnosis on structural imaging or initial post-iodine treatment scan. The features significantly associated with synchronous metastasis or recurrence were employed in the generation of a predictive risk model. A separate cohort of 393 patients who received RAI in 2017-2021 was used for validation. Results: On multivariate analysis, sTg ≥10 μg/L, extrathyroidal extension (ETE) and lymph node involvement predicted recurrence. Independent of ATA, patients with sTg ≥10 μg/L had a shorter disease-free survival (DFS) than those with sTg <10 μg/L (p < 0.001). The ETE stratified by four histological categories was significantly associated with worse DFS (p < 0.001). In a subset of patients, the presence of thyroglobulin antibody (TgAb) did not influence recurrence in patients with sTg <10 μg/L. On multivariate analysis, widespread ETE, sTg ≥10 μg/L, multifocal papillary thyroid cancer and follicular thyroid cancer were positively associated with synchronous metastasis. A predictive risk model was developed to estimate synchronous metastasis/recurrence risk and validated successfully in the second cohort. Conclusions: Our novel predictive risk model modifies and extends ATA stratification by including sTg and ETE, which we found to be independent predictors of both recurrence and synchronous metastasis in DTC.

Using 18F-FDG-PET/CT Metrics to Predict Survival in Ra-Dio-Iodine Refractory Thyroid Cancers

Radio-iodine refractory (RAI-R) differentiated thyroid cancer (DTC) is a rare disease with a poor prognosis and limited therapeutic resources. Therefore, identifying prognostic factors is essential in order to select patients who could benefit from an early start of treatment. The aim of this study is to identify positron emission tomography with 18F-fluorodeoxyglucose with integrated computed tomography (18F-FDG-PET/CT) parameters to predict overall survival (OS) in patients with RAI-R DTC. In this single-center retrospective study, we analyze the 18F-FDG-PET/CT parameters of 34 patients with RAI-R DTC between April 2007 and December 2019. The parameters collected are MTV, SUVmax and progression for each site of metastasis (neck, mediastinum, lungs, liver, bone) and total sites. ROC curves, Kaplan–Meier survival analysis curves, univariate and multivariate Cox analyses determine prognostic factors for 1-year and 5-year OS. The parameters for mediastinum, liver and total sites are significantly associated with worse 1-year and 5-year OS by both ROC curve analysis and Kaplan–Meier survival analysis. Univariate Cox analysis confirms significance of mediastinum SUVmax (HR 1.08; 95% CI [1.02–1.15]; p = 0.014) and total SUVmax (HR 1.06; 95% CI [1–1.12]; p = 0.042) for worse 1-year OS; of mediastinum SUVmax (HR 1.06; 95% CI [1.02–1.10]; p = 0.003), liver SUVmax (HR 1.04; 95% CI [1.01–1.08]; p = 0.02), liver MTV (HR 2.56; 95% CI [1.13–5.82]; p = 0.025), overall SUVmax (HR 1.05; 95% CI [1.02–1.08]; p = 0.001) and total MTV (HR 1.41; 95% CI [1.07–1.86]; p = 0.016) for worse 5-year OS. Multivariate Cox analysis confirms a significant association between liver MTV (HR 1.02; 95% CI [1–1.04]; p = 0.042) and decrease 1-year OS. In this study, we demonstrate that in RAI-R DTC, 18F-FDG-PET/CT parameters of the mediastinum, liver and overall tumor burden were prognostic factors of poor 1-year and 5-year OS. Identifying these criteria could allow early therapeutic intervention in order to improve patients’ survival.

Strategies for Radioiodine Treatment: What’s New

Radioiodine treatment (RAI) represents the most widespread and effective therapy for differentiated thyroid cancer (DTC). RAI goals encompass ablative (destruction of thyroid remnants, to enhance thyroglobulin predictive value), adjuvant (destruction of microscopic disease to reduce recurrences), and therapeutic (in case of macroscopic iodine avid lesions) purposes, but its use has evolved over time. Randomized trial results have enabled the refinement of RAI indications, moving from a standardized practice to a tailored approach. In most cases, low-risk patients may safely avoid RAI, but where necessary, a simplified protocol, based on lower iodine activities and human recombinant TSH preparation, proved to be just as effective, reducing overtreatment or useless impairment of quality of life. In pediatric DTC, RAI treatments may allow tumor healing even at the advanced stages. Finally, new challenges have arisen with the advancement in redifferentiation protocols, through which RAI still represents a leading therapy, even in former iodine refractory cases. RAI therapy is usually well-tolerated at low activities rates, but some concerns exist concerning higher cumulative doses and long-term outcomes. Despite these achievements, several issues still need to be addressed in terms of RAI indications and protocols, heading toward the RAI strategy of the future.

Nomogram Predicts Overall Survival in Patients With Stage IV Thyroid Cancer (TC): A Population-Based Analysis From the SEER Database

Background

Stage IV Thyroid cancer (TC) has a relatively poor prognosis and lacks a precise and efficient instrument to forecast prognosis. Our study aimed to construct a nomogram for predicting the prognosis of patients with stage IV TC based on data from the SEER programme.

Methods

We enrolled patients diagnosed with TC from 2004 to 2015 in the study. Furthermore, the median survival time (MST) for the patients equalled 25 months. The patients were split into two groups: the training group and validation group. We used descriptive statistics to calculate demographic and clinical variables, Student’s t test was used to describe continuous variables, and the chi-square test was used to describe classified variables. We used the concordance index (C-index) to evaluate discrimination ability and calibration plots to evaluate calibration ability. The improvement of the nomogram compared with the AJCC TNM system was evaluated by the net weight classification index (NRI), comprehensive discriminant rate improvement (IDI) and decision curve analysis (DCA).

Results

There were 3501 patients contained within our cohort, and the median follow-up was 25 months [quartile range (IQR): 6-60] in the whole population, 25 months (IQR: 6-60) in the training cohort, and 25 months (IQR: 5-59) in the validation cohort. The C-index value of the training cohort equalled 0.86 (95% CI: 0.85-0.87), and the value of the validation cohort equalled 0.85 (95% CI: 0.84-0.86). The NRI values were as follows: training queue: 1.16 for three-year and 1.12 for five-year OS prediction; authentication group: 1.22 for three-year and 1.21 for five-year OS prediction. The IDI values were as follows: training cohort: 0.25 for three-year and 0.21 for five-year OS prediction; validation cohort: 0.27 for three-year and 0.21 for five-year OS prediction. The DCA diagram showed that the nomogram was superior in predicting the three-year and five-year trends.

Conclusions

Our nomogram can be used to forecast the survival of patients with stage IV TC.

Age increased the cancer-specific mortality risk of thyroid cancer with lung metastasis

OBJECTIVE

To investigate the relationship between age and cancer-specific mortality in thyroid cancer (TC) with lung-metastasis.

PATIENTS AND METHODS

A total of 1418 patients with initial distant metastases from Surveillance, Epidemiology, and End Results databases were investigated. Patients with a median follow-up time of 8 months (interquartile range [IQR]: 2-27] and a median age of 66 years (IQR: 55-76) were divided into five groups by age and the association between age and TC-specific mortality was analysed.

RESULTS

The TC-specific mortality rates were 32.78% (118/360), 46.71% (156/334), 53.93% (199/369), 58.96% (158/268) and 82.76% (72/87) in patients aged ≤55 years, >55 but ≤65 years, >65 but ≤75 years, >75 but ≤85 years and >85 years. Kaplan-Meier curves showed that TC-specific mortality rate was associated with increased age (p < .001). Compared with patients ≤55 years, patients aged >55 but ≤65 years, >65 but ≤75 years, >75 but ≤85 years and >85 years had significantly higher hazard ratios (HRs) of 1.69 (1.26-2.26), 1.97 (1.47-2.64), 2.18 (1.59-2.99) and 3.24 (2.08-5.06) after adjustments for sex, tumour size and radiation therapy (all p < .001). In TC with initial lung-metastasis, compared with patients ≤55 years, patients aged >55 but ≤65 years, >65 but ≤75 years, >75 but ≤85 years and >85 years had significantly higher adjusted HRs of 1.68 (1.20-2.36; p = .003), 2.18 (1.57-3.02), 2.16 (1.51-3.08) and 2.91 (1.79-4.75; p < .001). Similar results were obtained in papillary TC.

CONCLUSIONS

The TC-specific mortality was increased with age in TC patients with initial lung-metastasis, indicating that further risk stratification based on age was necessary for TC over 55 years with lung-metastasis. Individual treatment strategies maybe recommended for such patients.

Metastatic papillary thyroid carcinoma presenting with elevated serum levels of carbohydrate antigen 19-9 (CA19-9): a case report

BACKGROUND

The major sites of distant metastases of papillary thyroid carcinoma (PTC) are the lung and bone; metastasis to the liver is rare. Although the postoperative serum thyroglobulin (Tg) level after total thyroidectomy is a good prognostic indicator for PTC when anti-thyroglobulin antibody (TgAb) is negative, the presence of TgAb interferes with the Tg assay, making serum Tg levels unreliable. Here we report a case of liver metastasis of PTC that presented with elevated serum levels of carbohydrate antigen 19-9 (CA19-9), which is usually a serum marker of pancreatic and gastrointestinal neoplasias.

CASE PRESENTATION

A 69-year-old man was diagnosed with PTC and underwent total thyroidectomy 16 years ago. The patient's serum Tg levels increased progressively during follow-up and his serum TgAb was negative. Positron emission tomography (PET) and computed tomography (CT) revealed metastases of the lung, cervical spine, mediastinum and liver. The liver lesion was a solitary tumor measuring 4.0 cm in the greatest dimension. His serum CA19-9 level was very high (326 U/mL), and intrahepatic cholangiocarcinoma was suspected from the results of various examinations including gastrointestinal endoscopic imaging and CT. Laparoscopic partial liver resection for segment 4 was performed. The histopathological diagnosis was a metastatic liver tumor from PTC. The immunohistological examination revealed that the liver tumor was positive for CA19-9 and Tg. The primary PTC, recovered from paraffin-embedded specimen, was also positive for CA19-9. After the surgery, his serum CA19-9 level as well as serum Tg level markedly decreased.

CONCLUSIONS

We presented the first reported case of liver metastasis of a PTC presenting with elevated serum levels of CA19-9 after total thyroidectomy. This case suggests that the serum CA19-9 levels may serve as a surrogate marker for PTC in place of the serum Tg level in patients with positive serum TgAb if the PTC and/or the metastatic lesions are positive for CA19-9 staining.

Risk factors associated with disease-specific mortality in papillary thyroid cancer patients with distant metastases

PURPOSE

Papillary thyroid carcinoma (PTC) is among the most curable cancer types. Even though uncommon, some patients present distant metastatic disease at diagnosis or during the follow-up and most of them have long-term survival. However, there continues to be controversies regarding what clinicopathological features are associated with mortality in these patients. This paper evaluates the factors related to poor disease-specific survival (DSS) in patients with metastatic PTC.

METHODS

A retrospective cohort study included PTC patients with distant metastasis from a tertiary public oncological center. Clinicopathological features, treatment modalities, and outcome were reviewed.

RESULTS

Between 1986 and 2014, 108 patients were diagnosed with metastatic PTC. In the multivariate analysis male sex (HR = 2.65; 95%CI: 1.08-6.53; P = 0.033), radioiodine refractory disease (HR = 9.50; 95%CI: 1.23-73.38; P = 0.031) and metastasis at multiple sites (HR = 5.91; 95%CI: 1.80-19.32; P = 0.003) were independent risk factors for death in patients with metastatic PTC.

CONCLUSION

Male patients with metastatic PTC, with radioiodine refractory disease and metastasis at multiple sites have a high risk of death.

Audit of Demographics, Treatment Patterns and Outcomes of Differentiated Thyroid Cancers Treated with Tyrosine Kinase Inhibitors

The real-world patterns of TKI use in differentiated thyroid cancer (DTC) are largely governed by the accessibility and financial feasibility of the patient with more sorafenib use compared to lenvatinib. There are limited data available on the toxicity profile, safety and tolerance of sorafenib and lenvatinib in DTC. Hence, we audited our practice on DTC. This is a retrospective single-centre analysis of patients with DTC who were referred to the Department of Medical Oncology for systemic therapy. Baseline demographics (age, sex, ECOG PS, comorbidities, substance use), tumour details (site of metastasis), previous treatment details, clinical features at metastasis (symptoms), the pattern of treatment, adverse events and outcomes including progression and death were extracted. There were 67 patients with DTC referred for systemic therapy; the median age was 56 (33-81) with a male preponderance (55.6%). The most common reason to start TKI therapy was radioactive iodine (RAI) cumulative dose > 600 milliCurie, followed by low iodine uptake in the RAI low-dose scan done at progression. The most common TKI used in the first line was sorafenib in 56 (83.6%) patients followed by lenvatinib in 9 (13.4%) patients. Papillary thyroid carcinoma was the most common histology (51, 76.1%), and the rest were follicular carcinoma (16, 23.9%). With a median follow-up of 36 months, the median PFS was 13.2 months (95% CI 10.4-16.0). The median OS was 18.8 months (95% CI 10.0-27.6). Among variables tested, no factors had a significant impact on the PFS or OS. The most common adverse events were hand-foot syndrome (54, 80.5%), diarrhoea (23, 33.3%) and transaminitis (24, 34.4%). The pattern of care of patients with RAI-refractory DTC is TKI therapy, especially sorafenib and lenvatinib in the real-world settings with comparable efficacy and safety profile compared to international literature.

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.

A rare case of differentiated thyroid carcinoma with liver metastases

Papillary thyroid carcinoma (PTC) is the most frequent type of differentiated thyroid cancers (DTCs) and commonly metastasizes to regional lymph nodes. Distant metastases of DTC typically occur in the lungs and bones. Liver metastases of DTC are very rare and difficult to diagnose. We present a case of a 52-year-old woman who had a previous history of PTC treated by total thyroidectomy and lymph node dissection. The patient received two radioactive iodine-131 (I-131) treatments. The second postradioiodine therapy whole-body scan (WBS) revealed intense iodine uptake in the neck region and in the lungs. After 2 months, during the follow-up period, increase in serum thyroglobulin (Tg) level was detected. Positron-emission tomography–computed tomography (PET-CT) with 18F-fluorodeoxyglucose (FDG) revealed increased FDG uptake in the mass lesion that invaded the muscles in the neck area, lung, bone, and liver. The uptake in liver was interpreted as suspicion of malignancy. The trucut biopsy of the liver masses demonstrated metastases of the thyroid carcinoma with the immunohistochemical thyroid transcription factor-1 and PAX8 positivity observed in these tumor cells. In DTC patients with progressive rapid rise of Tg level, the diagnostic value of I-131 WBS will decrease as the differentiation of the tumor decreases. The combined use of I-131 WBS and FDG PET-CT as diagnostic modalities in these patients will be important in treatment planning in detecting locoregional or distant metastases, especially in patients with negative diagnostic I-131 WBS.

Radioactive Iodine for Papillary Thyroid Carcinoma

Radioactive iodine is given after total thyroidectomy for remnant ablation or treatment of residual/metastatic disease. The decision and dose of radioactive iodine should be in a personalized and patient-specific approach, taking account the clinical-pathological features, risk stratification, patient's preference, and facilities of the institutions. We review the principles and use of radioactive iodine in differentiated thyroid cancer.

Differentiating pulmonary metastasis from benign lung nodules in thyroid cancer patients using dual-energy CT parameters

OBJECTIVES

To explore the importance of quantitative characteristics of dual-energy CT (DECT) between pulmonary metastasis and benign lung nodules in thyroid cancer.

METHODS

In this retrospective study, we identified 63 patients from our institution's database with pathologically proven thyroid cancer who underwent DECT to assess pulmonary metastasis. Among these patients, 22 had 55 pulmonary metastases, and 41 had 97 benign nodules. If nodules showed increased iodine uptake on I-131 single-photon emission computed tomography-computed tomography or increased size in follow-up CT, they were considered metastatic. We compared the clinical findings and DECT parameters of both groups and performed a receiver operating characteristic analysis to evaluate the optimal cutoff values of the DECT parameters.

RESULTS

Patients with metastases were significantly older than patients with benign nodules (p = 0.048). The DECT parameters of the metastatic nodules were significantly higher than those of the benign nodules (iodine concentration [IC], 5.61 ± 2.02 mg/mL vs. 1.61 ± 0.98 mg/mL; normalized IC [NIC], 0.60 ± 0.20 vs. 0.16 ± 0.11; NIC using pulmonary artery [NIC_PA], 0.60 ± 0.44 vs. 0.15 ± 0.11; slope of the spectral attenuation curves [λHU], 5.18 ± 2.54 vs. 2.12 ± 1.39; and Z-effective value [Z_eff], 10.0 ± 0.94 vs. 8.79 ± 0.75; all p < 0.001). In the subgroup analysis according to nodule size, all DECT parameters of the metastatic nodules in all subgroups were significantly higher than those of the benign nodules (all p < 0.05). The cutoff values for IC, NIC, λHU, NIC_PA, and Z_eff for diagnosing metastases were 3.10, 0.29, 3.57, 0.28, and 9.34, respectively (all p < 0.001).

CONCLUSIONS

DECT parameters can help to differentiate metastatic and benign lung nodules in thyroid cancer.

KEY POINTS

• DECT parameters can help to differentiate metastatic and benign lung nodules in patients with thyroid cancer. • DECT parameters showed a significant difference between benign lung nodules and lung metastases, even for nodules with diameters ≥ 3 mm and < 5 mm. • Among the DECT parameters, the highest diagnostic accuracy for differentiating pulmonary metastases from benign lung nodules was achieved with the NIC and IC, followed by the NIC_PA and λHU, and their cutoff values were 0.29, 3.10, 0.28, and 3.57, respectively.

STAT3/LINC00671 axis regulates papillary thyroid tumor growth and metastasis via LDHA-mediated glycolysis

Lactate dehydrogenase A (LDHA), a critical component of the glycolytic pathway, relates to the development of various cancers, including thyroid cancer. However, the regulatory mechanism of LDHA inhibition and the physiological significance of the LDHA inhibitors in papillary thyroid cancer (PTC) are unknown. Long non-coding RNA (lncRNA) plays a vital role in tumor growth and progression. Here, we identified a novel lncRNA LINC00671 negatively correlated with LDHA, downregulating LDHA expression and predicting good clinical outcome in thyroid cancer. Moreover, hypoxia inhibits LINC00671 expression and activates LDHA expression largely through transcriptional factor STAT3. STAT3/LINC00671/LDHA axis regulates thyroid cancer glycolysis, growth, and lung metastasis both in vitro and in vivo. In thyroid cancer patients, LINC00671 expression is negatively correlated with LDHA and STAT3 expression. Our work established STAT3/LINC00671/LDHA as a critical axis to regulate PTC growth and progression. Inhibition of LDHA or STAT3 or supplement of LINC00671 could be potential therapeutic strategies in thyroid cancer.

Plasma Lipidomics Profiling Reveals Biomarkers for Papillary Thyroid Cancer Diagnosis

The objective of this study was to identify potential biomarkers and possible metabolic pathways of malignant and benign thyroid nodules through lipidomics study. A total of 47 papillary thyroid carcinomas (PTC) and 33 control check (CK) were enrolled. Plasma samples were collected for UPLC-Q-TOF MS system detection, and then OPLS-DA model was used to identify differential metabolites. Based on classical statistical methods and machine learning, potential biomarkers were characterized and related metabolic pathways were identified. According to the metabolic spectrum, 13 metabolites were identified between PTC group and CK group, and a total of five metabolites were obtained after further screening. Its metabolic pathways were involved in glycerophospholipid metabolism, linoleic acid metabolism, alpha-linolenic acid metabolism, glycosylphosphatidylinositol (GPI)—anchor biosynthesis, Phosphatidylinositol signaling system and the metabolism of arachidonic acid metabolism. The metabolomics method based on PROTON nuclear magnetic resonance (NMR) had great potential for distinguishing normal subjects from PTC. GlcCer(d14:1/24:1), PE-NME (18:1/18:1), SM(d16:1/24:1), SM(d18:1/15:0), and SM(d18:1/16:1) can be used as potential serum markers for the diagnosis of PTC.

Percutaneous thermal ablation of lung metastases from thyroid carcinomas. A retrospective multicenter study of 107 nodules. On behalf of the TUTHYREF network

PURPOSE

To determine efficacy and safety of thermal ablation (TA) for the local treatment of lung metastases of thyroid cancer.

METHODS

We retrospectively studied 47 patients from 10 centers treated by TA (radiofrequency, microwaves, and cryoablation) over 10 years. The endpoints were overall survival (OS), local efficacy, complications (CTCAE classification), and factors associated with survival. OS curves after first TA were built using the Kaplan-Meier method and compared with the log-rank test.

RESULTS

A total of 107 lung metastases during 75 sessions were treated by radiofrequency (n = 56), microwaves (n = 9), and cryoablation (n = 10). Median follow-up time after TA was 5.2 years (0.2-13.3). OS was 93% at 2 years (95% confidence interval (CI): 86-94) and 79% at 3 years (95% CI: 66-91). On univariate and multivariate analysis with a Cox model, histology was the only significant factor for OS. OS at 3 years was 94% for follicular, oncocytic, or papillary follicular variant carcinomas, compared to 59% for papillary, medullary, insular or anaplastic carcinomas (P = 0.0001). The local control rate was 98.1% at 1 year and 94.8% at 2, 3, 4, and 5 years. Morbidity was low with no major complications (grade 4 and 5 CTCAE) and no complications in 29 of 75 sessions (38.7%).

CONCLUSIONS

TA is a useful, safe and effective option for local treatment of lung metastases from thyroid carcinoma. Prolonged OS was obtained, especially for lung metastases from follicular, oncocytic, or papillary follicular variant carcinomas. Achieving disease control with TA delays the need for systemic treatment.

Impact of lung metastases on overall survival in the phase 3 SELECT study of lenvatinib in patients with radioiodine-refractory differentiated thyroid cancer

BACKGROUND

Lung metastases may worsen overall survival (OS) in patients with radioiodine-refractory differentiated thyroid cancer (RR-DTC). We investigated (post hoc) the impact of lung metastases on survival in SELECT (a phase 3 study).

PATIENTS AND METHODS

392 patients with RR-DTC were randomised 2:1 to lenvatinib 24 mg daily (n = 261) or placebo (n = 131). Placebo-treated patients could crossover to open-label lenvatinib following progression. Patients were grouped by size of baseline lung metastases. Safety/efficacy outcomes, collated by these lung-metastases subgroups, were generated.

RESULTS

Lenvatinib-treated population distributions per baseline lung metastases subgroup were any lung metastases (target/nontarget lesions; n = 226), and by maximum size of target lung lesions ≥1.0 cm (n = 199), ≥1.5 cm (n = 150), ≥2.0 cm (n = 94) and <2.0 cm (n = 105). In patients with any lung metastases, no statistically significant difference in OS was observed between treatment arms (HR: 0.76; 95% CI: 0.57-1.01; P = 0.0549). Median OS for lung metastases of ≥1.0 cm was 44.7 months (lenvatinib) versus 33.1 months (placebo) (HR: 0.63; 95% CI: 0.47-0.85; P = 0.0025). OS was significantly prolonged with lenvatinib versus placebo among patients with lung metastases of ≥1.0 cm, ≥1.5 cm, ≥2.0 cm and <2.0 cm; median OS was shorter in the ≥2.0 cm subgroup (lenvatinib: 34.7 months) versus other subgroups (lenvatinib: 44.1-49.2 months). Multivariate analysis demonstrated lenvatinib significantly prolonged OS in patients with lung metastases of ≥1.0 cm after adjustment for baseline characteristics.

CONCLUSIONS

Lenvatinib treatment resulted in longer OS in patients with lung metastases of ≥1.0 cm versus placebo (even with the 89% crossover rate). Early initiation of lenvatinib may improve outcomes in patients with RR-DTC and lung metastases of ≥1.0 cm.

SOURCE STUDY REGISTRATION

ClinicalTrials.Gov Identifier: NCT01321554.

Radioactive iodine therapy may not improve disease-specific survival in follicular variant papillary thyroid cancer without distant metastasis: A propensity score-matched analysis

BACKGROUND

Whether radioactive iodine (RAI) therapy is effective in improving disease-specific survival (DSS) in patients with follicular variant papillary thyroid cancer (FVPTC) without distant metastasis remains unclear.

METHODS

Patients with FVPTC were identified from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. The Kaplan-Meier method and the Cox proportional hazards regression model were used to evaluate DSS. Propensity score-matched analysis was performed to reduce the influence of confounding bias.

RESULTS

RAI did not improve DSS, even in patients with aggressive features such as T4 classification (p = 0.658), extrathyroidal extension (p = 0.083), lateral lymph node metastasis (p = 0.544), and ≥5 metastatic lymph nodes (p = 0.599).

CONCLUSION

RAI did not affect DSS in patients with FVPTC without distant metastases in this SEER database study. Multicenter, prospective studies including recurrence and molecular information should be conducted to comprehensively evaluate the effects of RAI on FVPTC.

Early detection of progressive disease using thyroglobulin doubling-time in metastatic differentiated thyroid carcinoma treated with radioactive iodine

OBJECTIVE

Detectable serum thyroglobulin (Tg) in patients with differentiated thyroid carcinoma (DTC) after total thyroidectomy indicates progression of the disease. Thyroglobulin doubling-time (TgDT) is a powerful prognostic predictor in patients with DTC. We aimed to evaluate the value of the dynamic TgDT for early detection of progressive disease (PD) in the patients of metastatic DTC with I radioactive iodine (RAI) therapy.

METHODS

We retrospectively evaluated 21 patients undergoing RAI therapy with metastatic DTC. Patients were defined as PD or non-PD according to Response Evaluation Criteria in Solid Tumors 1.1. TgDT was calculated by Excel-based software using Tg values measured during routine follow-up. Whole data (WDT), initial four data (IDT) and recent four data (RDT) of TgDT after total thyroidectomy were calculated and compared.

RESULTS

Among the 21 patients (10 men; median age, 62 years old; range, 33-80), 11 patients were classified into PD and 10 were into non-PD. The initial Tg after total thyroidectomy showed a significant difference between PD and non-PD patients (P = 0.013). Short WDT, IDT and RDT (less than one year) showed a high correlation with PD (P < 0.05). RDT showed the highest predictive value for PD (P < 0.001). All the 11 PD patients showed RDT less than one year before PD (median follow-up, 157 days; range, 88-252).

CONCLUSIONS

RDT is a powerful PD predictor in patients with metastatic DTC. Dynamic monitoring of RDT should be applied for the early detection of PD in clinic.

Radioactive Iodine Therapy in Patients With Thyroid Carcinoma With Distant Metastases: A SEER-Based Study

Distant metastasis (DM) is the dominant negative prognosis for thyroid carcinoma. Radioactive iodine (RAI) therapy serves as an effective treatment for thyroid carcinoma. However, resistance to RAI occurs in patients with DMs. The present study aims to discriminate patients who may benefit from RAI. We extracted patients with thyroid cancer in the Surveillance, Epidemiology, and End Results program and analyzed thyroid cancer–specific survival after radiotherapy based on age and grade subgroups. A total of 1608 patients having DMs were eligible, including 521 (32.4%) cases with bone metastasis, 90 (5.6%) cases with brain metastasis, 158 (9.8%) cases with liver metastasis, 995 (61.9%) cases with lung metastasis, and 50 (3.1%) cases with other metastases. Advanced age, poor differentiation, follicular carcinoma, lymphatic metastasis, tumor size >10 mm, and extracapsular invasion are associated with pulmonary metastases. With respect to patients with DM, RAI therapy improved the survival in the age <45 years group and the well-/moderately differentiated group. For patients with pulmonary metastasis, RAI improved the survival in the higher grade group but did not have a strong effect in the better grade group. Our data indicate that the disparity of metastatic sites has different risk factors. Similarly, this finding indicates that RAI should be precisely applied to patients who undergo DM but are young and have well-/moderately differentiated tumors and may improve survival in pulmonary metastasis patients with poor grade tumors.

Patient and tumor factors contributing to distant metastasis in well-differentiated thyroid cancer: a retrospective cohort study

BACKGROUND

Distant metastasis in thyroid cancer significantly reduces survival in patients with well-differentiated thyroid carcinoma (WDTC). There is limited information available to clinicians regarding pathological features that confer a higher risk of distant metastasis (DM). This study aimed to identify patient and tumor factors that were associated with the development of DM over time in patients with WDTC.

METHODS

A retrospective cohort analysis of patients with WDTC (n = 584) at our institution was performed between 2007 and 2017. A total of 39 patients with DM and 529 patients with no DM (NDM) were included. Patient demographics, tumor characteristics and patient survival were compared between the DM and NDM groups using a univariate analysis. Multivariate Cox-proportional hazards model was used to evaluate the risk of developing distant metastasis over time. Kaplan-Meier analysis was used to compare survival between the DM and NDM groups.

RESULTS

Distant metastasis had a substantial impact on disease-specific survival (DSS) at 5 and 10-years in the DM group; 71.0% (SE 8.4%) and 46.9% (SE 11.6%) respectively, compared to 100% survival in the NDM group (p < 0.001). The DM group had significantly higher proportions of males, lymphovascular invasion (LVI), nodal metastasis (NM), large tumor size (TS), extrathyroidal extension (ETE), positive resection margins, multifocality, follicular thyroid cancer (FTC), tall cell variant of papillary thyroid cancer (PTC), and Hurthle cell carcinoma (HCC), when compared to the NDM group (p < 0.05). A TS ≥ 2 cm (Hazard Ratio (HR) 1.370), NM (HR 3.806) and FTC (HR 7.068) were associated with a significantly increased hazard of developing distant metastasis in patients with WDTC.

CONCLUSIONS

TS ≥ 2 cm, NM and FTC are associated with a significantly increased propensity for developing DM in our cohort of WDTC patients.

Clinical, Pathological, and Molecular Characteristics Correlating to the Occurrence of Radioiodine Refractory Differentiated Thyroid Carcinoma: A Systematic Review and Meta-Analysis

Background: Recently, radioiodine refractory differentiated thyroid cancer (RR-DTC) has received increasing attention due to its poor prognosis. The roles of clinical, pathological, and molecular features in the development of RR-DTC remain controversial and require additional investigation. This study aimed to evaluate the association between these risk factors and the occurrence of RR-DTC.

Methods: We performed a systematic search for relevant literature following the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) in PubMed, EMBASE, Medline, SCOPUS, and Web of Science up to the July 15, 2020. Observational studies that investigated the risk factors for RR-DTC were included. Fixed- or random-effects models were used to calculate pooled odds ratios (ORs) or mean differences (MD) with corresponding 95% confidence intervals.

Results: We included 13 eligible studies incorporating 1,431 cases, of which 603 were patients with RR-DTC. The pooled analysis indicated that four parameters significantly increased the risk of RR-DTC: extrathyroidal extension (ETE) (OR: 2.28, 95% CI: 1.43–3.64, I² = 14%), BRAF^V600E mutation (OR: 3.60, 95% CI: 1.74–7.46, I² = 69%), TERT promoter mutation (OR: 9.84, 95% CI: 3.60–26.89, I² = 61%) and high-risk histological subtype (OR: 1.94, 95% CI: 1.15–3.27, I² = 15%), including tall cell variant papillary thyroid carcinoma (PTC), sclerosing diffuse PTC, hobnail variant PTC, follicular thyroid carcinoma (FTC) (including Hürthle cell), and poorly differentiated thyroid carcinoma (PDTC). However, there was no statistical significance regarding sex, age, tumor size, multifocality, or lateral lymph node metastasis. Subgroup and sensitivity analyses were conducted to further confirm the robustness of the results.

Conclusions: Histological subtype, ETE, BRAF^V600E mutation, and TERT promoter mutation could be considered clinicopathological factors and biomarkers. They could assist in risk stratification, prognostic prediction, and individual therapy options for RR-DTC.

Liver resection for metastatic thyroid carcinoma. Case report and literature review

Liver resection for metastatic cancer has become the standard of care for specific groups of patients, including noncolorectal non-neuroendocrine liver metastases (NCNNELM). Liver metastasis from differentiated thyroid carcinoma is considered rare, with an approximated frequency of 0.5%. We present a case of metastatic papillary thyroid carcinoma (PTC) to the liver and literature review. Herein, we report a 72-year-old male that underwent formal left hepatectomy for 4.4 cm metastatic PTC generating left bile duct obstruction. Two months after, presented with multiple small lesions within the hepatic parenchyma and diffuse ductal dilatation of the right biliary system. Therefore, treated with a percutaneous biliary drain placement without complications. In a patient diagnosed with initial Stage II PTC, undergoing total thyroidectomy 10 years before presenting to the clinic. Bearing over a decade of treatments for local and distal recurrences. We believe approaching strategies for this specific disease should be developed to establish standard management.

The Benefit of Primary Tumor Surgical Resection in Distant Metastatic Carcinomas of the Thyroid

OBJECTIVES/HYPOTHESIS

Thyroid cancer with distant metastasis (TCDM) at diagnosis has significantly worse survival rates when compared to localized/regional thyroid cancer. This study sought to report on the characteristics of patients presenting with TCDM and the potential survival advantage of surgical resection.

STUDY DESIGN

Data were acquired from the Surveillance, Epidemiology, and End Results (SEER) database with cases from 2004 to 2015.

METHODS

TCDM cases (n = 2,558) were identified from the SEER database. The Bonferroni correction was applied for multivariate analysis. Kaplan-Meier analysis was utilized to obtain disease-specific survival (DSS) rates. Cox regression analysis was utilized to identify independent factors significantly associated with survival.

RESULTS

The average age of diagnosis of TCDM was 62.0 (±17.5) years. Patients were predominantly white (74.6%), female (54.6%), in a relationship (56.0%), and between ages 36 and 80 years (76.4%). Cases consisted of papillary (57.2%), follicular (16.0%), medullary (8.9%), anaplastic (17.9%) TCDM histological variants. Overall 1-, 5-, and 10-year DSS rates were 72.0%, 56.8%, and 43.8%, respectively. Anaplastic and medullary variants had the worst 10-year DSS (0% and 25.5%, respectively). Patients who underwent surgical resection only and surgical resection with radiation were 49% and 59% less likely to die, respectively. Treatment, age, histology, T staging, relationship status, and metastasis site were determined to be significant predictors of survival.

CONCLUSIONS

Surgical resection with radiation was found to be a significant predictor of survival after applying the Bonferroni correction for all thyroid cancer variants except medullary. To increase survival, surgical intervention should be recommended in patients who are deemed to be medically tolerant of surgery.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:1026-1034, 2021.

Dynamic Risk Stratification for Predicting Treatment Response in Differentiated Thyroid Cancer

Prognosis in Differentiated Thyroid Cancer (DTC) patients is excellent, but a significant degree of overtreatment still exists because of the inability to accurately identify small patient cohorts who experience a more aggressive form of the disease, often associated with certain poor prognostic factors. Identifying these cohorts at an early stage would allow patients at high risk to receive more aggressive treatment while avoiding unnecessary and invasive treatments in those at low risk. Most risk stratification systems include age, tumor size, grade, presence of local invasion, and regional or distant metastases. Here we discuss these common factors as well as their association with treatment response, but also other upcoming markers including histology and multifocality of primary tumor, dose administered and preparation method for Radioiodine Therapy (RAI), Thyroglobulin (Tg), Anti-thyroglobulin Antibodies (Tg-Ab) levels both at initial management and during follow-up, and the presence of previously existing benign thyroid disease. In addition, we examine the role of remnant size and avidity as well as surgeons' experience in performing thyroidectomies with recurrence rate, discussing its impact on disease prognosis. Our results reveal that treatment response has a statistically significant association with histology, T and M stages, surgeons' experience, Tg levels and remnant score both during RAI and follow up and Tg-Ab levels during follow-up whole body scan (WBS).

Single liver metastasis of a follicular variant of papillary thyroid carcinoma: a rare pattern of organ spread

SUMMARY

Well-differentiated thyroid cancer (WDTC), including papillary, follicular, and Hurthle-cell types, is characterized by a slow course and usually remain localized to the thyroid. However, a minority of these cases develop distant metastases with the most common sites being lungs, bones, and lymph nodes. Liver metastases of WDTC are rare and are usually found along with other distant metastases sites and in a multiple or diffuse pattern of spread. The recognition of distant metastasis in WDTC has a significant impact on the treatment and prognosis. However, because of their low incidence and awareness, distant metastases are often diagnosed late. Herein, we describe a case of a 71 years old woman who during routine surveillance of a follicular variant of papillary thyroid cancer (FV-PTC), 5 years after being treated for her primary thyroid tumor, was found to have a single liver metastasis and underwent liver segmental resection. This case highlights the importance of maintaining vigilant surveillance of patients with WDTC, and illustrates the possibility of unique metastasis at unexpected sites. Further studies are needed to understand the organ tropism of some WDTC leading to distant metastases development and to better prediction of an aggressive course.

LEARNING POINTS

WDTC patients with distant metastases have a poor prognosis with a 10-year survival of about 50%. The most common sites of distant metastases are lung, bone and lymph nodes. Liver metastases are rare in WDTC, are usually multiple or diffuse and are found along with other distant metastases sites. Single liver metastasis of WDTC is an unexpected pattern of spread, and very few cases are reported in the literature. Rare sites of distant metastases in WDTC can manifest many years after the primary tumor, stressing the importance of maintaining vigilant surveillance. More studies are needed to predict which WDTC tumors may develop a more aggressive course, allowing clinicians to individualize patient management.

Peptide Receptor Radionuclide Therapy in Patients With Differentiated Thyroid Cancer: A Meta-analysis

PURPOSE

As patients with progressive medullary thyroid cancer (MTC) and radioiodine-refractory metastatic differentiated nonmedullary thyroid cancer (DTC) have poor prognoses and present therapeutic challenges, peptide receptor radionuclide therapy (PRRT) targeting the somatostatin receptor provides a promising option. This meta-analysis evaluated the therapeutic effects and outcomes of PRRT in differentiated thyroid cancer.

PATIENTS AND METHODS

PUBMED, EMBASE, CINAHL, SCOPUS, and COCHRANE were systematically searched using appropriate key words. The primary therapeutic effect was the radiological response after PRRT, and the objective response rate (ORR) and disease control rate (DCR) were identified in MTC and DTC, respectively. The outcome of serious adverse events (grade 3 or 4), additional therapeutic effects of F-FDG PET/CT and biochemical (calcitonin and thyroglobulin) responses, and radionuclides for PRRT were assessed as subgroup analyses. The parameters were generated as pooled proportions.

RESULTS

Eleven articles with 165 patients were included (98 patients with MTC and 67 patients with DTC). PRRT achieved pooled proportions of ORR in 8.53% to 15.61%, DCR in 53.95% to 59.99%, and serious adverse events in 2.79% to 2.82% in MTC and DTC patients. F-FDG PET/CT and biochemical responses revealed similar results as the radiological response. Lu-based PRRT (ORR, 11.48%-24.52%; DCR, 61.47%-67.26%) showed better therapeutic effects than Y-based PRRT (ORR, 6.98%-13.82%; DCR, 50.86%-57.29%).

CONCLUSIONS

This meta-analysis suggests that PRRT could be a potential and safe strategy for MTC and DTC. In particular, PRRT with Lu exhibited improved therapeutic effects relative to PRRT with Y.

Metastatic propagation of thyroid cancer; organ tropism and major modulators

Thyroid cancer, as the most prevalent endocrine malignancy, comprises nearly 1% of all cancers in the world. The metastatic propagation of thyroid cancer is under the control of a number of modulating processes and factors such as signaling pathways and their components, cell division regulators, metabolic reprogramming factors, extracellular matrix remodelers, epithelial to mesenchymal transition modulators, epigenetic mechanisms, hypoxia and cytokines. Identifying the exact molecular mechanisms of these dysregulated processes could help to discover the key targets for therapeutic purposes and utilizing them as diagnostic, prognostic and predictors of the clinical course of patients. In this review article, we describe different aspects of thyroid cancer metastasis by focusing on defective genes and pathways involved in its metastatic spread.

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.

Modern surgery for advanced thyroid cancer: a tailored approach

Surgical treatment of advanced thyroid malignancy can be morbid, compromising normal functions of the upper aerodigestive tract. There is a paucity of guidelines dedicated to the management of advanced disease. In fact, there is not even a uniform definition for advanced thyroid cancer currently. The presence of local invasion, bulky cervical nodes, distant metastases or recurrent disease should prompt careful preoperative evaluation and planning. Surgical strategy should evolve from multidisciplinary discussion that integrates individual disease characteristics and patient preference. Intraoperative neuromonitoring has important applications in surgery for advanced disease and should be used to guide surgical strategy and intraoperative decision-making. Recent paradigm shifts, including staged surgery and use of neoadjuvant targeted therapy hold potential for decreasing surgical morbidity and improving clinical outcomes. Modern surgical planning provides optimal treatment for each patient through a tailored approach based on exact extent and type of disease as well as incorporating appreciation of surgical complications, patient preferences and intraoperative findings.

The Association Between Lymph Node Stage and Clinical Prognosis in Thyroid Cancer

Purpose: To investigate the association between lymph node (N) stage and clinical outcome in thyroid cancer patients with initial distant metastasis. Methods: A total of 3,198 cases (1,435 males and 1,763 females) between 2004 and 2015 with initial distant metastasis were obtained from the surveillance, epidemiology, and end results (SEER) database. Patients with a median follow up time of 13 months and a median age of 66 years were analyzed. A total of 1,407 cases had detailed information regarding the four most common metastatic organs after the year 2010. Kaplan-Meier (KM) analyses, log-rank tests, Cox regression, and logistic regression analyses were used. Results: Among the whole cohort, 33.4% (1,069/3,198), 14.5% (464/3,198), 10.1% (322/3,198), 34.2% (1,094/3,198), and 7.8% (249/3,198) of the patients were at the stage of N0, NX, N1a, N1b, and N1NOS (referring to metastasis to regional lymph nodes but not otherwise specified), respectively. The KM curves demonstrated that the patients at the NX stage had the worst survival. The NX and N1b groups had the highest hazard ratios (HRs) of 1.83 (95%CI 1.46-2.31) and 1.78 (95%CI 1.52-2.10) after adjusting age, race, gender, and tumor size (p < 0.001) compared with N0 group. The lung was the most common metastatic site, with a rate of 51.2% (720/1,407). Compared with the N0 group, N1 patients had higher odds (OR 1.63, 95%CI 1.31-2.01, p < 0.001) for lung metastasis. Similar results were obtained in papillary thyroid cancer (PTC) sub-cohort. Conclusions: Overall, the TC patients at the NX stage had the highest mortality risk, followed by N1b, N1a, and N0 groups. Compared with N0 patients, N1 patients were more likely to have lung metastasis. The poor prognosis for TC patients with the NX stage may make more aggressive treatment reasonable.

Long-Term Outcomes and Prognoses of Elderly Patients (≥65-Years-Old) With Distant Metastases From Well-Differentiated Thyroid Cancer During Radioiodine Therapy and Follow-Up

OBJECTIVE

The objective of this study was to investigate the clinicopathological characteristics, long-term outcomes, and prognostic factors of elderly patients with distant metastases at initial diagnosis from well-differentiated thyroid cancer (WDTC) during radioactive iodine (¹³¹I) treatment and follow-up.

METHODS

A retrospective review of medical records identified 183 elderly patients with DTC who underwent ¹³¹I treatment at our institution between 2006 and 2019.

RESULTS

In total, 57 elderly WDTC patients with distant metastases were enrolled in this study. After ¹³¹I treatment, 32 (56.14%) patients had ¹³¹I avidity and 25 (43.86%) had non-¹³¹I avidity; 35 (61.40%) cases were classified as radioiodine refractory (RR)-WDTC and 22 (38.60%) as non-RR-WDTC. At the end of follow-up, 25 (43.86%) patients had died and 32 (56.14%) were alive. The 5- and 10-year overall survival (OS) rates were 71.50% and 30.49%, respectively, while the 5- and 10-year disease-specific survival (DSS) rates were 76.89% and 48.71%, respectively. Multivariate analyses showed that gross extrathyroidal extension and RR-DTC were independent prognostic factors for poor OS (P=0.04 and P=0.03, respectively), while gross extrathyroidal extension, extrapulmonary distant metastases, and RR-WDTC were independent prognostic factors for poor DSS at the end of follow-up (P=0.02, P=0.03, and P=0.02, respectively).

CONCLUSIONS

WDTC with distant metastases at initial diagnosis accounted for 31.15% of all elderly patients with DTC. Gross extrathyroidal extension and RR-DTC were the major factors associated with poor OS; gross extrathyroidal extension, extrapulmonary distant metastases, and RR-DTC were independent prognostic factors for poor DSS in elderly DTC patients with distant metastases.

Unusual metastases from differentiated thyroid carcinoma: analysis of 36 cases

PURPOSE

Metastases of differentiated thyroid cancer (DTC) in sites different from lungs and bone are unusual (UM); their impact in management and prognosis remains unknown. Our aim was to evaluate the prevalence of UM, to describe their characteristics and to analyze their impact in disease outcome and mortality.

METHODS

We retrospectively reviewed the file records from 8 different centers. Those patients with DTC and UM were included. UM were diagnosed by: (i) biopsy/cytology and/or (ii) radioiodine (RAI) uptake associated to elevated thyroglobulin (Tg) levels and/or c) presence of one or more structural lesion/s with 18-FDG uptake in the PET/CT scan and elevated Tg levels.

RESULTS

Thirty-six (0.9%) out of a total of 3982 DTC patients were diagnosed with UM; 75% had papillary histology. The most frequent localization was central nervous system (CNS, 31%). UM were metachronous in 75%, symptomatic in 55.6% and fulfilled RAI-refractoriness criteria in 77.8% of cases. Metastatic lesions in lung/bone and/or locoregional disease were present in 34 cases (94.4%). Diagnosis of UM changed the therapeutic approach in 72.2% of patients. After a median follow up of 13 months, 21 (58.3%) patients died from DTC related causes. In 8 of them CNS progression was the immediate cause of death.

CONCLUSIONS

Prevalence of UM was low; they were frequently metachronic and RAI-refractory. Although UM were found in patients with widespread disease, their diagnosis usually led to changes in therapy. UM were associated with poor prognosis and high frequency of disease-specific mortality.

Predictive Factors of Recurrence in Patients with Differentiated Thyroid Carcinoma: A Retrospective Analysis on 579 Patients

Differentiated thyroid carcinoma (DTC) is usually associated with a favorable prognosis. Nevertheless, up to 30% of patients present a local or distant recurrence. The aim of this study was to assess the incidence of recurrence after surgery for DTC and to identify predictive factors of recurrence. We included in this retrospective study 579 consecutive patients who underwent thyroidectomy for DTC from 2011 to 2016 at our institution. We observed biochemical or structural recurrent disease in 36 (6.2%) patients; five-year disease-free survival was 94.1%. On univariate analysis, male sex, histotype, lymph node yield, lymph node metastasis, extrathyroidal invasion and multicentricity were associated with significantly higher risk of recurrence, while microcarcinoma was correlated with significantly lower risk of recurrence. On multivariate analysis, only lymph node metastases (OR 4.724, p = 0.012) and microcarcinoma (OR 0.328, p = 0.034) were detected as independent predictive factors of recurrence. Postoperative management should be individualized and commensurate with the risk of recurrence: Patients with high-risk carcinoma should undergo strict follow-up and aggressive treatment. Furthermore, assessment of the risk should be repeated over time, considering individual response to therapy.

Bone-Marrow Suppression in Elderly Patients Following Empiric Radioiodine Therapy: Real-Life Data

Background: Elderly patients with differentiated thyroid cancer (DTC) tend to have more advanced disease at presentation, for which high activities of radioiodine (RAI) are often recommended. However, the 2015 American Thyroid Association guidelines recommend that empirically administered activities of RAI >150 mCi should be avoided in patients >70 years of age, based on calculated bone-marrow exposure according to two dosimetry-based studies. This study aimed to evaluate the effect of RAI treatment on bone-marrow function in elderly DTC patients. Methods: DTC patients ≥70 years of age who received RAI treatment and on whom a complete blood count was performed before and after treatment were included. Blood counts within one year before RAI and one year following treatment were compared in order to assess for marrow suppression. The impact of demographic, clinical, and laboratory variables on complete blood count were assessed. Results: One hundred fifty-three treatments in 122 patients met inclusion criteria, with a mean patient age of 76 ± 4.3 years, and 75% were women. High-risk features at presentation included T4 disease in 17%, lymph node metastases in 34%, and distant metastases in 14%. Mean RAI activity was 136.8 ± 48 mCi (82% ≥ 100 mCi, 66% ≥ 150 mCi). Of 153 RAI treatments analyzed, 114 (74%) were first treatments, 28 (18%) second treatments, seven (5%) third treatments, and four (3%) fourth treatments. At 0-3 months after RAI treatment, there was a statistically significant decrease in platelets (238 ± 66 vs. 216 ± 69 × 10⁹/L, 10% decrease; p < 0.001), white blood cells (WBC; 6.9 ± 2 vs. 6.1 ± 1.9 × 10⁹/L, 13% decrease; p < 0.001), and hemoglobin (Hb) in women (12.8 ± 1.1 vs. 12.4 ± 1.1 g/dL, 3% decrease; p = 0.01). Mean platelets, WBC, Hb in women, and lymphocytes remained decreased (but within the reference range) one year after treatment. Subgroup analysis demonstrated platelet suppression only with activities ≥100 mCi, and WBC and Hb suppression only with activities ≥150 mCi, with mean values within the reference ranges. There were no clinically significant cytopenia events during follow-up. Conclusions: Empiric RAI treatment in elderly patients causes mild bone-marrow suppression, with little clinical significance. Activities of 150-200 mCi can be safely used when indicated.

Bone Metastases from Thyroid Carcinoma of Follicular Origin: A Single Institutional Experience

BACKGROUND/AIMS

Overall, 2-13% of patients with thyroid cancer develop bone metastases (BM). In addition to decreased survival, patients with BM may present skeletal-related events (SRE) that impair the quality of life. Our objectives were to characterize clinical features, treatment approaches, and outcomes of patients with thyroid cancer and BM.

MATERIAL AND METHODS

We identified patients diagnosed with thyroid carcinoma of follicular origin and BM followed at the Instituto Português de Oncologia de Lisboa Francisco Gentil (IPOLFG), Lisbon, Portugal, from 1991 to 2017. SRE were defined as the need for bone irradiation, bone surgery, spinal cord compression, or pathologic fractures.

RESULTS

The final cohort consisted of 86 patients, with a median follow-up time of 54 months (IQR 22.8-82.8), mainly women (67.4%), and a median age of 64 years (IQR 53.6-71.2). BM was the initial presentation of thyroid cancer in 36.0% of the patients. Bone involvement was multiple in 59.3% of the cases. Papillary carcinoma was the most frequent histological type, present in 47.7% of the patients, of which 56.1% presented the follicular variant. SRE were found in 76.7% of the patients. The most frequent SRE was radiotherapy (66.3%). Treatment with bisphosphonates was initiated in 19.8% of the patients. The 5-year specific survival was 60%, whereas the 10-year specific survival decreased to 50%. There were no differences in 5- or 10-year specific survival regarding gender, the occurrence of SRE, or histological type. However, patients with initial radioiodine non-avid lesions had a lower 5- and 10-year specific survival (p = 0.002).

DISCUSSION

The high frequency of patients with SRE was notable. The follicular variant of papillary thyroid cancer was the variant most commonly associated with BM, reflecting a more similar behavior to follicular carcinoma than the classic variant.

The Prognosis of Papillary Thyroid Cancer with Initial Distant Metastasis is Strongly Associated with Extensive Extrathyroidal Extension: A Retrospective Cohort Study

BACKGROUND

Extensive extrathyroidal extension (ETE) has a significant role in the prognosis of papillary thyroid cancer (PTC) without distant metastasis, but its role in PTC with initial distant metastasis has never been studied. This study aimed to evaluate the prognostic significance of extensive ETE regarding disease progression, survival, and remission in PTC patients with initial distant metastasis.

METHODS

This retrospective cohort study included PTC patients with initial distant metastasis who underwent total thyroidectomy with a median follow-up period of 6.7 years. The prognostic significance of extensive ETE was assessed in terms of time to tumor progression (TTP), cancer-specific survival (CSS), and cumulative incidence of remission with all-cause death as the competing event.

RESULTS

The study enrolled 64 patients. Of these patients, 21 (32.8%) had extensive ETE, which was associated with a shorter TTP (adjusted hazard ratio [HR], 4.10; p = 0.015) and a lower CSS rate (p = 0.002, log-rank), particularly for patients 55 years of age or older with stage 4b disease (10-year CSS rate: 33.3% in those with and 92.3% in those without extensive ETE; p = 0.017). Additionally, remission was observed only in patients without extensive ETE (10-year cumulative incidence of remission: 0.0% in those with and 29.3% in those without extensive ETE; p = 0.013).

CONCLUSIONS

Extensive ETE of the primary lesion results in poorer prognoses for PTC patients with initial distant metastasis. The high CSS rate for patients with stage 4b PTC but no extensive ETE indicates that the prognosis of this patient population should be distinguished from that of other stage 4 cases.

Association between BRAF (V600E) mutation and clinicopathological features of papillary thyroid carcinoma: a Brazilian single-centre case series

OBJECTIVES

We aimed to investigate the prevalence of the BRAF (V600E) mutation in consecutive cases of papillary thyroid carcinoma (PTC) in patients diagnosed and treated at the Hospital Sao Rafael (Salvador, BA, Brazil) and evaluate its association with clinical and pathological characteristics of PTC.

SUBJECTS AND METHODS

We retrospectively enrolled in the study a total of 43 consecutive PTC patients who underwent total thyroidectomy. We performed DNA extraction from formalin-fixed paraffin-embedded (FFPE) tumour tissue samples. Polymerase chain reaction (PCR) and direct sequencing were used to determine BRAF (V600E) mutation status. Univariate and multivariate logistic regression analyses were employed to identify independent associations.

RESULTS

The prevalence of BRAF (V600E) mutation was 65.1% (28/43). A high frequency of older patients (p value: 0.004) was observed among the BRAF-mutated PTC group and, in contrast, a low frequency of concurrent Hashimoto's thyroiditis (HT) (p value: 0.011) was noted. Multivariate analysis confirmed that older age (OR: 1.15; 95% CI: 1.00 - 1.33; p value: 0.047) and HT (OR: 0.05; 95% CI: 0.006-0.40; p value: 0.005) were independent factors associated with BRAF (V600E) mutation.

CONCLUSION

We found a high prevalence of BRAF (V600E) mutation in PTC cases. Older age and no concurrent HT were independently associated with BRAF (V600E) mutation.

Fear of Recurrence and View of Life Affect Health-Related Quality of Life in Patients with Differentiated Thyroid Carcinoma: A Prospective Swedish Population-Based Study

BACKGROUND

Differentiated thyroid cancer (DTC) has a good prognosis but a remaining risk of recurrence and need for lifelong follow-up. The aim was to study changes in health-related quality of life (HRQoL) from diagnosis to one year of follow-up.

METHODS

In this prospective population-based study, patients were identified from all the Swedish departments of oncology treating DTC. In total, 487 patients diagnosed with DTC between 2012 and 2017 were invited to answer the Swedish version of the Short Form-36 Health Survey (SF-36) and a study-specific questionnaire at diagnosis and after one year.

RESULTS

In total, 349 (72%) patients responded. Of these, 235 (67%) had reached one year of follow-up and also answered the questionnaire after one year. Of those, 23% had a negative view of life, and 75% had a fear of recurrence at diagnosis. These patients had a significantly lower HRQoL on eight and five of the SF-36 domains, respectively (p < 0.05). A negative view of life and a fear of recurrence also affected HRQoL negatively after one year of follow-up, with a significantly lower HRQoL on seven SF-36 domains for those reporting a negative view of life or fear of recurrence often (p < 0.05). Thyrotropin suppression did not affect HRQoL negatively. In regression models, HRQoL at diagnosis was the most important predictive factor for HRQoL at the one-year follow-up.

CONCLUSIONS

Despite a good prognosis, HRQoL was substantially affected at the time of diagnosis, with some improvements after one year. As fear of recurrence and a negative view of life substantially affect HRQoL, these patients should be given additional attention.

Clinical characteristics and disease outcome of patients with non-medullary thyroid cancer and brain metastases

Brain metastases from non-medullary thyroid carcinoma (NMTC) are rare, with a reported frequency of ~1%, and patient survival time is <1 year after diagnosis. The optimal management of brain metastases in this setting continues to be debated. The aim of the present study was to evaluate a series of patients with brain metastases from NMTC attending a single tertiary medical center. The electronic database of Rabin Medical Center was reviewed for all patients with NMTC and distant metastases who were diagnosed and treated between 1970 and 2014. Those with brain metastases were identified and formed the study group. Data were collected from medical records comprising clinicopathological characteristics, time intervals for diagnosis and treatment, treatment modalities and outcome. Of the 172 patients with NMTC and distant metastases, 10 possessed brain metastases. These included 6 females and 4 males of median age 53.5 years (range, 18–81 years). All patients had lung metastases and 7 demonstrated bone metastases. The median interval between the diagnoses of NMTC and brain metastases was 40 months (range, 9–207 months). Of the 10 patients, 1 presented with brain metastases at primary diagnosis. Treatment of the brain metastases consisted of surgery, radiotherapy (external beam, stereotactic), and radioiodine, alone or in combination. A total of 2 patients received tyrosine kinase inhibitors. The median overall survival time from diagnosis of brain metastasis was 15 months. A total of 2 patients remained alive at the last follow-up (32 and 300 months, respectively). The present study demonstrated that brain metastases may occur in ≤6% of patients with NMTC and distant metastases. Brain metastases rarely present at diagnosis of NMTC and are associated with metastases in other distant sites. Systematic screening for brain metastases requires consideration in all patients with NMTC and distant metastases. Some patients show an indolent evolution with overall survival of >2 years, supporting an aggressive treatment approach.