The changing incidence of thyroid cancer

A computer-aided diagnosing system in the evaluation of thyroid nodules-experience in a specialized thyroid center

Background

The evaluation of thyroid nodules with ultrasonography has created a large burden for radiologists. Artificial intelligence technology has been rapidly developed in recent years to reduce the cost of labor and improve the differentiation of thyroid malignancies. This study aimed to investigate the diagnostic performance of a novel computer-aided diagnosing system (CADs: S-detect) for the ultrasound (US) interpretation of thyroid nodule subtypes in a specialized thyroid center.

Methods

Our study prospectively included 180 thyroid nodules that underwent ultrasound interpretation. The CADs and radiologist assessed all nodules. The ultrasonographic features of different subtypes were analyzed, and the diagnostic performances of the CADs and radiologist were compared.

Results

There were seven subtypes of thyroid nodules, among which papillary thyroid cancer (PTC) accounted for 50.6% and follicular thyroid carcinoma (FTC) accounted for 2.2%. Among all thyroid nodules, the CADs presented a higher sensitivity and lower specificity than the radiologist (90.5% vs 81.1%; 41.2% vs 83.5%); the radiologist had a higher accuracy than the CADs (82.2% vs 67.2%) for diagnosing malignant thyroid nodules. The accuracy of the CADs was not as good as that of the radiologist in diagnosing PTCs (70.9% vs 82.1%). The CADs and radiologist presented accuracies of 43.8% and 60.9% in identifying FTCs, respectively.

Conclusions

The ultrasound CADs presented a higher sensitivity for identifying malignant thyroid nodules than experienced radiologists. The CADs was not as good as experienced radiologists in a specialized thyroid center in identifying PTCs. Radiologists maintained a higher specificity than the CADs for FTC detection.

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.

Contemporary Debates in Adult Papillary Thyroid Cancer Management

An ever-increasing population of patients with papillary thyroid cancer is engaging with health care systems around the world. Numerous questions about optimal management have arisen that challenge conventional paradigms. This is particularly the case for patients with low-risk disease, who comprise most new patients. At the same time, new therapies for patients with advanced disease are also being introduced, which may have the potential to prolong life. This review discusses selected controversial issues in adult papillary thyroid cancer management at both ends of the disease spectrum. These topics include: (i) the role of active surveillance for small papillary cancers; (ii) the extent of surgery in low-risk disease (lobectomy vs total thyroidectomy); (iii) the role of postoperative remnant ablation with radioiodine; (iv) optimal follow-up strategies in patients, especially those who have only undergone lobectomy; and (v) new therapies for advanced disease. Although our current management is hampered by the lack of large randomized controlled trials, we are fortunate that data from ongoing trials will be available within the next few years. This information should provide additional evidence that will decrease morbidity in low-risk patients and improve outcomes in those with distant metastatic disease.

Obesity and risk of differentiated thyroid cancer: A large-scale case-control study

OBJECTIVE

Recently, the incidence of thyroid cancer as well as obesity has dramatically increased worldwide. Whether obesity contributes to the development of differentiated thyroid cancer (DTC) remains controversial. We evaluated the relationship between anthropometric measurements and DTC risk.

DESIGN/PATIENTS/MEASUREMENTS

A large frequency-matched case-control study based on hospital data was performed. A total of 10 668 DTC patients and 11 858 controls were enrolled. Body mass index (BMI), body surface area (BSA) and body fat percentage (BF%) were calculated. An unconditional logistic regression model was applied.

RESULTS

The univariate analysis showed a significant increase in DTC risk with increased height, weight, BMI, BSA and BF%. The multivariate analysis also showed a positive relationship. Based on the Chinese BMI (CN-BMI) classification, for women of all ages, the ORs for DTC risk in overweight and obesity were 1.151 (1.037-1277) and 1.292 (1.092-1.528), respectively. For men under 50, the ORs were 1.221 (1.014-1.469) and 1.520 (1.202-1.923), respectively, but the ORs for men over 50 were not significant. Additionally, BSA showed a significant association with DTC risk for both sexes under 50 (P = .02 and P < .001). BF% remained significant only for women under 50 (P = .003). However, for both sexes over 50, neither BSA nor BF% was significantly associated with DTC risk. Based on The World Health Organization BMI (WHO-BMI) classification, for all women and men over 50, the results were consistent with CN-BMI. For men under 50, BF%, but not BMI, showed a significant association with DTC risk.

CONCLUSION

BMI, BSA and BF% were positively correlated with the risk of DTC, which was potentially affected by age and sex.

Identification of gene co-expression modules and hub genes associated with lymph node metastasis of papillary thyroid cancer

Papillary thyroid cancer (PTC) is the most prevalent histological type among thyroid cancers, and some patients are at a high risk for recurrent disease or even death. Identification for the potential biomarkers of PTC may contribute to early discovery of recurrence and treatment. In The Cancer Genome Atlas (TCGA) database, we obtained the information of RNA sequence data and clinical characteristics of PTC. Weighted gene co-expression network analysis (WGCNA) was performed to construct gene co-expression networks and investigate the relationship between modules and clinical traits. Finally, we constructed 16 co-expression modules in 10,428 genes, and three key modules (darkturquoise, lightyellow, and red) associated with tumor N grade were identified. The results of functional annotation indicated that the darkturquoise module was primarily enriched in the regulation of the extracellular matrix (ECM), collagen metabolism, and cell adhesion, the lightyellow module was primarily enriched in the mitochondrial function regulation and energy synthesis, and the red module was primarily enriched in the process of cell junction, apoptosis, and inflammatory response, suggesting their significant role in the progression of PTC. In addition, the hub genes in the three modules were identified and screened for differentially expressed genes (DEGs). Relapse-free survival analyses found that 11 genes (KCNQ3, MET, FN1, ITGA3, RUNX1, ITGA2, PERP, GCSH, FAAH, NGFRAP1, and HSPA5) may play a pivotal role in PTC relapse. In general, our research revealed the key co-expression modules and identified several prognostic biomarkers, which provides some new insights into the lymph node metastasis of PTC.

Whole-genome sequencing of synchronous thyroid carcinomas identifies aberrant DNA repair in thyroid cancer dedifferentiation

The genetics underlying thyroid cancer dedifferentiation is only partly understood and has not yet been characterised using comprehensive pan-genomic analyses. We investigated a unique case with synchronous follicular thyroid carcinoma (FTC), poorly differentiated thyroid carcinoma (PDTC), and anaplastic thyroid carcinoma (ATC), as well as regional lymph node metastases from the PDTC and ATC from a single patient using whole-genome sequencing (WGS). The FTC displayed mutations in CALR, RB1, and MSH2, and the PDTC exhibited mutations in TP53, DROSHA, APC, TERT, and additional DNA repair genes - associated with an immense increase in sub-clonal somatic mutations. All components displayed an overrepresentation of C>T transitions with associated microsatellite instability (MSI) in the PDTC and ATC, with borderline MSI in the FTC. Clonality analyses pinpointed a shared ancestral clone enriched for mutations in TP53-associated regulation of DNA repair and identified important sub-clones for each tumour component already present in the corresponding preceding lesion. This genomic characterisation of the natural progression of thyroid cancer reveals several novel genes of interest for future studies. Moreover, the findings support the theory of a stepwise dedifferentiation process and suggest that defects in DNA repair could play an important role in the clonal evolution of thyroid cancer. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Predicting factors for central or lateral lymph node metastasis in conventional papillary thyroid microcarcinoma

BACKGROUND

Optimal management for papillary thyroid microcarcinoma (PTMC) remains controversial. The purpose of this study was to explore risk factors predictive of cervical lymph node metastasis in conventional PTMCs.

METHODS

Conventional PTMC patients (n = 2,404) undergoing surgery between 2010 and 2017 were grouped and analyzed according to the positivity of cervical lymph node.

RESULTS

Central lymph node (CLN) metastases and lateral lymph node (LLN) metastases were observed in 915 (38.1%) and 184 (7.7%) cases, respectively. Multivariate analysis found that male (odds ratio [OR] = 1.974, p < 0.001), younger age (OR = 1.601, p < 0.001), tumor size (OR = 1.935, p < 0.001), extrathyroidal extension (ETE) (OR = 1.647, p < 0.001), multifocality (OR = 1.416, p < 0.001), and intrathyroidal spreading (OR = 3.355, p < 0.001) predicted increased CLN metastasis. In particular, younger age, multifocality, and intrathyroidal spreading were significantly associated with a high number of CLN metastases (n ≥ 5). The presence of CLN metastasis was strongly associated with LLN metastasis (OR = 5.426, p < 0.001).

CONCLUSION

Male, younger age, tumor size, ETE, multifocality, and intrathyroidal spreading predict increased CLN metastasis in PTMCs. In patients with suspicious lateral lymphadenopathy, the presence of CLN metastasis is independently associated with LLN metastasis.

MiR-155 promotes anaplastic thyroid cancer progression by directly targeting SOCS1

BACKGROUND

Anaplastic thyroid cancer (ATC) is considered to be a rare type of thyroid cancer but takes up the most important proportion of thyroid cancer-related deaths. Therefore, the development of molecular targeted therapy is an exciting strategy in the management of ATC.

METHODS

miR-155 and SOCS1 expression were measured by qRT-PCR as well as western blot analysis. 8305c and FRO cells were transfected and cultured for apoptosis assays, transwell, MTT on miR-155 or SOCS1 suppression and overexpression. Dual-luciferase reporter assays and SOCS1 restoration experimentswas implemented for define the relation between SOCS1 and miR-155. In addition, the correlation between miR-155 expression and patients' clinicopathological features were also explored.

RESULTS

Aberrant miR-155 and SOCS1 expression and inverse correlation were found in ATC samples. In addition, it indicated that miR-155 expression correlated with cervical metastasis as well as extrathyroidal invasion. Moreover, we demonstrated that miR-155 inhibited 8305c and FRO cells apoptosis, promoted proliferation, invasion and migration. Furthermore, miR-155 inhibition was associated with a significant overexpression of SOCS1. Additionally, luciferase reporter assays presented that miR-155 could bind to SOCS1 3'-UTR, influencing its stability negatively and finally lowering SOCS1 levels. Moreover, it was illustrated that the impacts of miR-155 suppression were reversed by the inhibition of SOCS1 on cell proliferation, apoptosis as well as invasion.

CONCLUSIONS

Aberrant miR-155/SOCS1 expression has been included in ATC progression: miR-155 overexpression leads to SOCS1 suppression and develops ATC progression. Thus, miR-155 has been considered to be an underlying therapeutic target for ATC.

MicroRNA-96-3p promotes metastasis of papillary thyroid cancer through targeting SDHB

Background

MicroRNA (MiRNA) is a small non-coding RNA which is implicated in a cohort of biological function in cancer, including proliferation, metastasis, apoptosis and invasion. MiR-96 has been reported to be involved in many cancers, including papillary thyroid cancer. However, the role of miR-96-3p in papillary thyroid cancer metastasis is still unclear.

Methods

qRT-PCR is used to detect the level of miR-96-3p and mRNA of SDHB in PTC tissues and cell lines. Western blot assays are used to verify the protein expression of SDHB. The transwell assays are performed to identify the migration ability of PTC cell lines. Moreover, dual-luciferase 3'-UTR reporter assays are chosen to illuminate the direct target of miR-96-3p.

Results

The relative miR-96-3p upregulate in PTC tissues and three PTC cell lines (B-CPAP, K-1 and TPC-1 cells) while the relative SDHB is opposite. Our results revealed that the miR-96-3p promotes metastasis and invasion in PTC cell lines (K-1 and TPC-1 cells) by direct targeting SDHB and influence the downstream protein AKT.

Conclusions

Taken together, the miR-96-3p is involved in PTC metastasis and invasion by direct targeting SDHB and the downstream molecule AKT and mTOR.

PKA Activates AMPK Through LKB1 Signaling in Follicular Thyroid Cancer

Thyroid cancer affects about one percent of the population, and has seen rising incidence in recent years. Follicular thyroid cancer (FTC) comprises 10-15% of all thyroid cancers. Although FTC is often localized, it can behave aggressively with hematogenous metastasis, leading to an increased risk of cancer death. We previously described a mouse model for FTC caused by tissue-specific ablation of the Protein Kinase A (PKA) regulatory subunit Prkar1a, either by itself or in combination with knockout of Pten. Loss of Prkar1a causes enhanced activity of PKA, whereas ablation of Pten causes activation of Akt signaling. At the molecular level, these genetic manipulations caused activation of mTOR signaling, which was also observed in human FTC cases. To understand the mechanism by which PKA activates mTOR, we began by studying intracellular kinases known to modulate mTOR function. Although AMP-activated kinase (AMPK) has been characterized as a negative regulator of mTOR activity, our tumor model exhibited activation of both AMPK and mTOR. To understand the mechanism by which AMPK was turned on, we next studied kinases known to cause its phosphorylation. In this paper, we report that PKA leads to AMPK activation through the LKB1 kinase. Although LKB1 has traditionally been considered a tumor suppressor, our data indicates that it may have a complex role in the thyroid gland, where its activation appears to be frequently associated with follicular thyroid carcinoma in both mice and humans.

Clinical outcomes and prognostic factors in patients with no less than three distant organ system metastases from differentiated thyroid carcinoma

OBJECTIVES

For patients with differentiated thyroid carcinoma (DTC), distant metastases are commonly identified in the lungs and bones. However, they are relatively rare in other distant organs, such as the liver, kidneys, or brain. The aim of the current study was to describe the clinical outcomes and evaluate the prognostic factors of patients with no less than three different distant organ system metastases from DTC.

METHODS

This study retrospectively identified 717 patients diagnosed with DTC with distant metastases between January 2005 and December 2017. Patient response to radioactive iodine (RAI) therapy was monitored by changes in serum thyroglobulin levels and imaging changes. Five-year and 10-year overall survival (OS) rates were calculated by the Kaplan-Meier methods and Cox proportional hazards.

RESULTS

Among the 717 participants, 37 (5.16%) patients had no less than three different distant organ system metastases from DTC. Five-year and 10-year OS were 45.9% and 37.8% in patients with three or more distant organ system metastases while 74.5% and 64.9% in individuals with one or two distant organ system metastases, respectively. RAI avidity and RAIR-DTC were main independent prognostic factors influencing the clinical outcomes for both groups of patients. The presence of 3 or more different distant organ system metastases was the only independent prognostic factors for 10-year OS by multivariate analysis.

CONCLUSIONS

Patients with no less than three distant organ system metastases from DTC had poor prognosis. RAI avidity and RAIR-DTC were main factors influencing overall survival for patients with distant metastases from DTC in both groups.

Clinical Efficacy of Frameless Stereotactic Radiosurgery in the Management of Spinal Metastases From Thyroid Carcinoma

STUDY DESIGN

A retrospective data review.

OBJECTIVE

To evaluate the efficacy of CyberKnife (CK) stereotactic radiosurgery (SRS) for thyroid spinal metastasis (SMs).

SUMMARY OF BACKGROUND DATA

Thyroid carcinoma is an infrequent cause of SM. The absolute efficacy of SRS generally and CK in particular remains poorly characterized for thyroid SM. The current study is the first to specifically evaluate the efficacy of CK SRS for thyroid SMs.

METHODS

A retrospective review of patients at our institution between 2003 and 2013 was done. Details about tumor location, radiographic findings before and after CK SRS, tumor recurrence, prescription isodose level, total and maximum dose, number of fractions, and gross tumor volume coverage were similarly collected. For comparison with other studies, the biologically effective dose and the equivalent total dose in 2 Gy fractions were calculated. Each patient was assessed for survival and local disease control from the time of the first CK session and survival analysis was carried out using the Kaplan-Meier method. Risk factors for local failure were assessed using multivariate logistic regression.

RESULTS

A total of 12 patients with 32 spinal metastases from thyroid carcinoma that were treated with CK SRS were identified. Survival for 1, 2, and 3 years was 55%, 44%, and 33%, and local control was 67%, 56%, and 34% respectively. The study found that the single strongest factor associated with local control was prior radiotherapy (β-coefficient -27.72, P = 0.01). No complications occurred in the immediate or late follow-up period.

CONCLUSION

This was the first study to specifically investigate the efficacy of CK for treatment of thyroid SMs. Our findings suggest that CK can be safely used to treat spinal SMs from thyroid cancer and is associated with a high rate of local control.

LEVEL OF EVIDENCE

4.

Interconnection between circadian clocks and thyroid function

Circadian rhythmicity is an approximately 24-h cell-autonomous period driven by transcription-translation feedback loops of specific genes, which are referred to as 'circadian clock genes'. In mammals, the central circadian pacemaker, which is located in the hypothalamic suprachiasmatic nucleus, controls peripheral circadian clocks. The circadian system regulates virtually all physiological processes, which are further modulated by changes in the external environment, such as light exposure and the timing of food intake. Chronic circadian disruption caused by shift work, travel across time zones or irregular sleep-wake cycles has long-term consequences for our health and is an important lifestyle factor that contributes to the risk of obesity, type 2 diabetes mellitus and cancer. Although the hypothalamic-pituitary-thyroid axis is under the control of the circadian clock via the suprachiasmatic nucleus pacemaker, daily TSH secretion profiles are disrupted in some patients with hypothyroidism and hyperthyroidism. Disruption of circadian rhythms has been recognized as a perturbation of the endocrine system and of cell cycle progression. Expression profiles of circadian clock genes are abnormal in well-differentiated thyroid cancer but not in the benign nodules or a healthy thyroid. Therefore, the characterization of the thyroid clock machinery might improve the preoperative diagnosis of thyroid cancer.

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.

Altered Serum MicroRNA Profile May Serve as an Auxiliary Tool for Discriminating Aggressive Thyroid Carcinoma from Nonaggressive Thyroid Cancer and Benign Thyroid Nodules

Thyroid cancers are the most common malignancy of the endocrine system; however, there is no reliable blood biomarkers for thyroid cancer diagnosis and even for aggressive and nonaggressive thyroid cancers as well as benign nodule discrimination. The present study is aimed at evaluating whether circulating microRNA (miRNA) can differentiate aggressive and nonaggressive thyroid cancer from benign thyroid nodules. In this study, we performed a multiphase, case-control study to screen serum miRNA expression profile in 100 patients with papillary thyroid cancer (PTC), 15 patients with aggressive medullary thyroid carcinoma (MTC), 91 patients with benign nodules, and 89 healthy controls using TaqMan low-density array followed by extensive reverse transcription quantitative real-time PCR validation. The results showed that the serum levels of miR-222-3p, miR-17-5p, and miR-451a were markedly increased, while miR-146a-5p, miR-132-3p, and miR-183-3p were significantly decreased in the PTC and benign nodule groups compared with the control group. There was no difference in the miRNA expression profile between the PTC group and the benign nodule group. Nevertheless, the serum levels of miR-222-3p and miR-17-5p were significantly increased in the MTC group than the benign nodule and control group. Moreover, receiver operating characteristic curve analyses demonstrated that the 2 miRNAs and their panel can accurately discriminate MTC from the benign nodule group and healthy controls. These findings indicated that the altered circulating miRNAs may discriminate PTC and benign thyroid nodules from controls, and serum miR-222-3p and miR-17-5p have the potential to serve as auxiliary tools for diagnosing more aggressive thyroid carcinomas, such as MTC.

The cholesterol-derived metabolite dendrogenin A functionally reprograms breast adenocarcinoma and undifferentiated thyroid cancer cells

Dendrogenin A (DDA) is a tumor suppressor mammalian cholesterol-derived metabolite and a new class of ligand of the Liver X receptor (LXR), which displays tumor cell differentiation. In human MCF7 breast adenocarcinoma cells, DDA-induced cell differentiation was associated with an increased accumulation of neutral lipids and proteins found in milk indicating that DDA re-activates some functions of lactating cells. Active iodide transport occurs in the normal lactating mammary cells through the sodium/iodide symporter (NIS) and iodide (I) is secreted into milk to be used by the nursing newborn for thyroid hormones biosynthesis. In the present study, we assessed whether DDA may induce other characteristic of lactating cells such as NIS expression and iodine uptake in MCF7 breast cancer cells and extended this study to the papillary B-CPAP and undifferentiated anaplastic 8505c thyroid cancer cells. Moreover, we evaluated DDA impact on the expression of thyroid specific proteins involved in thyroid hormone biogenesis. We report here that DDA induces NIS expression in MCF7 cells and significantly increases the uptake of 131-I by acting through the LXR. In addition, DDA induces phenotypic, molecular and functional characteristics of redifferentiation in the two human thyroid carcinoma cell lines and the uptake of 131-I in the undifferentiated 8505c cells was associated with a strong expression of all the specific proteins involved in thyroid hormone biosynthesis, TSH receptor, thyroperoxidase and thyroglobulin. 131-I incorporation in the 8505c cells was stimulated by DDA as well as by the synthetic LXR ligand, GW3965. Together these data show that the re-differentiation of breast and thyroid cancer cells by DDA, is associated with the recovery of functional NIS expression and involves an LXR-dependent mechanism. These results open new avenues of research for the diagnosis of thyroid cancers as well as the development of new therapeutic approaches for radioiodine refractory thyroid cancers.

Characterization of Activating Mutations of the MEK1 Gene in Papillary Thyroid Carcinomas

Background: Genetic alterations activating the mitogen-activated protein kinase (MAPK) signaling pathway, most commonly BRAF and RAS mutations, are common in papillary thyroid carcinoma (PTC). Somatic mutations of the MEK gene, also known as mitogen-activated protein kinase kinase 1 (MAP2K1), coding for a signaling protein downstream of BRAF, have been found in several cancer types. The goal of this study was to investigate if functional MEK1 mutations occur in thyroid cancer (TC). Methods: We analyzed MEK1 mutation status in a series of 101 PTCs lacking other known driver mutations using Sanger sequencing and targeted next-generation sequencing. In addition, 64 follicular and Hürthle cell carcinomas and 32 follicular adenomas were studied. The occurrence of MEK1 mutations was evaluated using another series of thyroid tumors studied by targeted next-generation sequencing. Western blot and RNA-seq analyses were performed on selected tumors. Results: We detected MEK1 mutations in 2/101 (2%) PTCs that otherwise had no known genetic alterations, in 0/64 follicular and Hürthle cell carcinomas, and in 0/32 follicular adenomas. Two positive tumors carried the same in-frame deletion p.L98_I103del; K104I (c.292_309del18; c.311A>T) located in exon 3 of the gene. One additional MEK1 mutation was identified following routine molecular tumor profiling. The tumor had an in-frame deletion p.I99_K104del (c.294_311del18) also located in exon 3. Western blot analysis of one of the tumors showed activation of the MAPK pathway. Using RNA-seq analysis to evaluate changes in gene expression, these tumors were RAS-like and showed a high thyroid differentiation score. Phenotypically, the MEK1-positive PTCs were all encapsulated and had a predominantly or exclusively follicular architecture, being diagnosed as a classic papillary type with a significant follicular pattern ( × 2) or follicular variant PTC ( × 1). Follow-up was available for 2 patients, with no evidence of disease found 2 and 10 years postsurgery. Conclusions: In this study, we report the occurrence of functional MEK1 mutations in PTC. All mutations are in-frame deletions in exon 3 of MEK1, representing another mechanism of activation of the MAPK pathway in papillary carcinomas with a predominantly follicular growth pattern.

I-124-PET/US Fusion Imaging in Comparison to Conventional Diagnostics and Tc-99m Pertechnetate SPECT/US Fusion Imaging for the Function Assessment of Thyroid Nodules

The purpose of this study is to investigate I-124 positron emission tomography (PET)/ultrasound (US) fusion imaging for function assessment of thyroid nodules. In 70 patients, 201 lesions were examined with conventional diagnostics (CD) (thyroid US, laboratory findings and Tc-99m pertechnetate scintigraphy), Tc-99m pertechnetate single photon emission computed tomography (SPECT) and I-124 PET/computed tomography (CT). Subsequently, US fusion imaging (SPECT/US and PET/US) was performed by three experienced investigators. Patients referred for thyroid diagnostics in a clinical routine setting were included in this study if CD produced equivocal results. PET/US was superior to CD and SPECT/US in 96% and 86%, respectively, and ambiguous findings in CD were clarified by PET/US in 96% of the 70 patients. Regarding nodule-based function assessment, 10% (66%), 39% (14%) and 71% (4%) of the 201 lesions were rated with absolute certainty (equivocal or uncertain) using CD, SPECT/US and PET/US, respectively (p < 0.001). PET/US has the potential to improve the function assessment of thyroid nodules in comparison to CD.

High Rates of Underlying Thyroid Cancer in Patients Undergoing Thyroidectomy for Hyperthyroidism

BACKGROUND

The rate of thyroid cancer in patients with hyperthyroidism is reported to be rare, and patients with toxic thyroid nodules do not routinely undergo fine-needle aspiration (FNA) to evaluate for malignancy. However, higher rates of malignancy in hyperthyroid patients may exist than previously reported. This study examines the rate of malignancy in patients with hyperthyroidism who have undergone thyroidectomy.

METHODS

A retrospective review of prospectively collected data of 138 patients with hyperthyroidism who underwent thyroidectomy at a single institution was performed. Patients were divided into three groups: Graves' disease (n = 80), toxic multinodular goiter (n = 46), and toxic solitary nodule (n = 12). Patients with previous thyroid surgery were excluded from the study. All patients had biochemical confirmation of hyperthyroidism with thyroid-stimulating hormone <0.1 mIU/L and clinical diagnosis by a referring physician.

RESULTS

Of 138 patients, 22% (31/138) were found to have malignancy on final pathology. The breakdown of malignancy by hyperthyroid condition was as follows: 16% in Graves' disease, 24% in toxic multinodular goiter patients, and 50% in toxic solitary nodule patients.

CONCLUSIONS

There is a clinically significant rate of malignancy seen in patients who undergo thyroidectomy for hyperthyroidism. Patients with distinct thyroid nodules in the presence of hyperthyroidism may have the highest rates of malignancy and should undergo appropriate workup with ultrasound and FNA to exclude underlying malignancy. In cases with suspicious ultrasound features and/or FNA cytopathology, surgical treatment should be considered as initial management.

Predictive value of LN metastasis detected by 18F-FDG PET/CT in patients with papillary thyroid cancer receiving iodine-131 radiotherapy

The aim of the present study was to predict the prognostic value of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in the metastatic lymph nodes (mLNs) of patients with papillary thyroid carcinoma (PTC) with a negative iodine-131 (¹³¹I) whole-body scan (WBS). The present retrospective study included 32 patients with PTC undergoing standard surgery and radioiodine treatment. All patients received ¹⁸F-FDG PET/CT imaging prior to and following therapy. All mLNs were divided into an effective treatment group (group A) and ineffective treatment group (group B) based on the PET Response Criteria in Solid Tumors 1.0 guidelines. All the patients were followed up for ≥9 months. A significant difference was identified in the peak standardized uptake value (SULpeak) between group B (7.85±3.20) and group A (5.36±2.19). A cut-off value of 5.85 was used to distinguish ineffective treatment of lesions from mLNs receiving radioactive ablation based on receiver operating characteristic (ROC) curve analysis with an area under the ROC curve of 0.755. Patients with a high SULpeak (P=0.003) and extrathyroidal extension (P=0.030), confirmed by pathology, more frequently exhibited a poor prognosis. In conclusion, tracer uptake of ¹⁸F-FDG for cervical metastatic nodes was revealed as a predictor for the clinical outcome of patients with PTC treated with radioiodine therapy. The present results also indicated that high SULpeak and extrathyroidal extension are poor predictors for patients with mLNs receiving ¹³¹I therapy.

Long noncoding RNA ABHD11-AS1 functions as a competing endogenous RNA to regulate papillary thyroid cancer progression by miR-199a-5p/SLC1A5 axis

With the increasing incidence of papillary thyroid cancer (PTC), more attention has been paid to exploring the mechanism of PTC initiation and progression. In addition, ectopic expression of long noncoding RNAs (lncRNAs) is reported to play a pivotal role in multiple human cancers. Based on these findings, we examined lncRNA ABHD11 antisense RNA 1 (ABHD11-AS1) expression and its clinical significance, biological function and mechanism in PTC. First, we analyzed thyroid ABHD11-AS1 expression in The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Then, qRT-PCR was applied to detect the expression in paired PTC tissues and adjacent normal tissues, as well as in PTC cell lines (TPC-1 and K-1) and a normal thyroid follicular epithelium cell line (Nthy-ori3-1). In addition, we validated the relationship between ABHD11-AS1 expression and clinicopathological features by the Pearson X² test. The oncogenic role of ABHD11-AS1 and its regulation of miR-199a-5p in PTC were examined by biological assays. Finally, bioinformatics analysis and mechanism assays were used to elucidate the underlying mechanism. We found that ABHD11-AS1 was remarkably overexpressed in PTC, and high expression was related to tumor size, lymph node metastasis, extrathyroidal extension and advanced TNM stage. Moreover, ABHD11-AS1 enhanced the abilities of cell proliferation, migration, and invasion, inhibited apoptosis in vitro, promoted tumorigenesis in vivo via sponging miR-199a-5p and then induced SLC1A5 activation. In addition, rescue assays were performed to confirm the ABHD11-AS1/miR-199a-5p/SLC1A5 axis. Taken together, the data show that ABHD11-AS1 acts as a competing endogenous RNA (ceRNA) to exert malignant properties in PTC through the miR-199a-5p/SLC1A5 axis. Therefore, our study may shed light on PTC diagnosis and therapies.

Exposure to Polybrominated Diphenyl Ethers and a Polybrominated Biphenyl and Risk of Thyroid Cancer in Women: Single and Multi-Pollutant Approaches

BACKGROUND

Thyroid cancer incidence is the most rapidly increasing malignancy; rates are three times higher in women than men. Thyroid hormone-disrupting flame-retardant chemicals, including polybrominated diphenyl ethers (PBDE) and polybrominated biphenyls (PBB), may contribute to this trend.

METHODS

We investigated the relationship between PBDE/PBB exposure and papillary thyroid cancer (PTC) in 250 incident female papillary thyroid cancer cases and 250 female controls frequency-matched on age. Interviews and postdiagnostic serum samples were collected from 2010 to 2013. Serum samples were analyzed for 11 congeners. We calculated ORs and 95% confidence intervals (95% CI) using single-pollutant logistic regression models for continuous and categorical lipid-adjusted serum concentrations of PBDE/PBB, adjusted for age, alcohol consumption, and education. We applied three multi-pollutant approaches [standard multipollutant regression models, hierarchical Bayesian logistic regression modeling (HBLR), principal components analysis (PCA)] to investigate associations with PBDE/PBB mixtures.

RESULTS

In single-pollutant models, a decreased risk was observed at the highest (>90th percentile) versus lowest (<median) category of BDE-209 concentrations (OR, 0.47; 95% CI, 0.23-0.98); an elevated PTC risk was observed at the highest versus lowest category of BB-153 concentrations (OR, 1.81; 95% CI, 0.96-3.39). In standard multi-pollutant models, an interquartile range increase in BDE-100 concentrations was associated with increased PTC risk (OR, 1.18; 95% CI, 1.01-1.38). HBLR and PCA yielded no statistically significant results.

CONCLUSIONS

Our results using single- and multi-pollutant modeling do not generally support a positive association with PBDE/PBB and PTC risk.

IMPACT

Prospective studies with more advanced statistical approaches to analyze mixtures and populations with higher exposures could reveal new insights.

Thyroid Cancer: The Quest for Genetic Susceptibility Involving DNA Repair Genes

The incidence of thyroid cancer (TC), particularly well-differentiated forms (DTC), has been rising and remains the highest among endocrine malignancies. Although ionizing radiation (IR) is well established on DTC aetiology, other environmental and genetic factors may also be involved. DNA repair single nucleotide polymorphisms (SNPs) could be among the former, helping in explaining the high incidence. To further clarify the role of DNA repair SNPs in DTC susceptibility, we analyzed 36 SNPs in 27 DNA repair genes in a population of 106 DTCs and corresponding controls with the aim of interpreting joint data from previously studied isolated SNPs in DNA repair genes. Significant associations with DTC susceptibility were observed for XRCC3 rs861539, XPC rs2228001, CCNH rs2230641, MSH6 rs1042821 and ERCC5 rs2227869 and for a haplotype block on chromosome 5q. From 595 SNP-SNP combinations tested and 114 showing relevance, 15 significant SNP combinations (p < 0.01) were detected on paired SNP analysis, most of which involving CCNH rs2230641 and mismatch repair variants. Overall, a gene-dosage effect between the number of risk genotypes and DTC predisposition was observed. In spite of the volume of data presented, new studies are sought to provide an interpretability of the role of SNPs in DNA repair genes and their combinations in DTC susceptibility.

Targeting PLKs as a therapeutic approach to well-differentiated thyroid cancer

Polo-like kinases (PLKs) are pivotal regulators of cell proliferation and cell survival; therefore, PLKs may be potential targets in the treatment of malignancy. The therapeutic effects of volasertib, a PLKs inhibitor for papillary and follicular thyroid cancer (known as well-differentiated thyroid cancer (WDTC)), were evaluated in this study. Volasertib inhibited cell proliferation in two papillary and two follicular thyroid cancer cell lines in a dose-dependent manner. Volasertib treatment reduced cells in the S phase and increased cells in the G2/M phase. Volasertib activated caspase-3 activity and induced apoptosis. Drug combinations of volasertib and sorafenib showed mostly synergism in four well-differentiated thyroid carcinoma cell lines in vitro. Volasertib treatment in vivo retarded the growth of a papillary thyroid tumor model. Furthermore, the combination of volasertib with sorafenib was more effective than a single treatment of either in a follicular thyroid cancer xenograft model. Promising safety profiles appeared in animals treated with either volasertib alone or volasertib and sorafenib combination therapy. These findings support volasertib as a potential drug for the treatment of patients with WDTC.

Hsa_circ_0058124 promotes papillary thyroid cancer tumorigenesis and invasiveness through the NOTCH3/GATAD2A axis

Background

Despite a good and overall prognosis, papillary thyroid cancer (PTC) can still affect the quality of life of many patients, and can even be life-threatening due to its invasiveness and metastasis. Emerging studies demonstrate that circular RNAs (circRNAs) participate in the regulation of various cancers. However, the circRNA profile in invasive PTC is still not well understood.

Methods

Competing endogenous RNA (ceRNA) microarrays were performed to determine circRNAs contributed to the tumorigenesis and invasiveness of PTC. Bioinformatics methods were used to narrow down the candidate circRNAs. Quantitative real-time polymerase chain reaction (qRT-PCR) assays revealed a significant upregulation of hsa_circ_0058124 in PTC tissue and a close correlation with a poor prognosis for PTC patients. RNA fluorescence in situ hybridization and Cell fractionation assay were used to investigate the subcellular location of hsa_circ_0058124. Then, we examined the functions of hsa_circ_0058124 in PTC by cell proliferation, cell cycle, apoptosis, migration and invasion assay. Mechanistically, RNA sequencing and GSEA analysis were applied to predict the downstream pathway of hsa_circ_0058124. Dual-luciferase report assays were used to explore the potential miRNA sponge role of hsa_circ_0058124. Western blotting, cell proliferation, cell cycle, cell apoptosis, migration and invasion, and mouse xenograft assay were used to validate the effects of hsa_circ_0058124/NOTCH3/GATAD2A axis on PTC progression.

Results

In the current study, a novel hsa_circ_0058124 on 2q35 was identified and explored in PTC. Hsa_circ_0058124 is associated with the malignant features and poor outcomes of PTC patients. Hsa_circ_0058124 acts as an oncogenic driver that promotes PTC cell proliferation, tumorigenicity, tumor invasion, and metastasis, which functions as a competing endogenous RNA to modulate miRNA-218-5p and its target gene NUMB expression, and consequently with repression of the NOTCH3/GATAD2A signaling axis in vitro and in vivo.

Conclusions

This study unveils a novel biomarker panel consisting of the hsa_circ_0058124/NOTCH3/GATAD2A axis which is critical for PTC tumorigenesis and invasiveness and may represent a novel therapeutic target for intervening in PTC progression.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1321-x) contains supplementary material, which is available to authorized users.

Birthweight and risk of thyroid cancer and its histological types: A large cohort study

BACKGROUND

The aetiology of thyroid cancer is poorly understood, but it is possible that this malignancy has origins early in life. It is, however, currently unknown if birthweight, as an indicator of prenatal growth, is related to thyroid cancer risk.

OBJECTIVE

To investigate if birthweight is associated with the later risk of thyroid cancer and its histological types.

METHODS

246,141 children (120,505 girls, 125,636 boys) from the Copenhagen School Health Records Register, born 1936-1989, were prospectively followed in the Danish Cancer Registry. Cox regressions were used to estimate hazards ratios (HR) and 95% confidence intervals (CI).

RESULTS

During follow up, 241 individuals (172 women, 69 men) were diagnosed with thyroid cancer (162 papillary, 53 follicular). Birthweight was significantly and positively associated with risk of thyroid cancer overall (HR = 1.30 [95% CI: 1.03-1.64] per kilogram). There were no sex differences in the associations. Birthweight was positively and significantly associated with follicular thyroid cancer (HR = 1.74 [95% CI: 1.07-2.82] per kilogram), and although there was an indication of a positive association, it did not reach statistical significance for the more common papillary type (HR = 1.20 [95% CI: 0.90-1.59] per kilogram).

CONCLUSION

A heavier weight at birth is associated with an elevated risk of total and follicular thyroid cancer, which underscores that prenatal exposures may be important in thyroid cancer aetiology.

Evaluating pre- and post-operation plasma miRNAs of papillary thyroid carcinoma (PTC) patients in comparison to benign nodules

Background

Thyroid cancer is the most common endocrinology cancer that its incidence has increased in recent decades. miRNAs are new biomarkers in recent studies in the diagnosis and follow-up of these patients.

Methods

Blood and thyroid tissue samples were obtained from two groups of included patients (PTC and benign nodules), pre- and post-operation. miRNAs were extracted from these plasma samples and were measured quantitatively. After cDNA synthesis, qPCR was carried out. Then tissue samples were investigated, and their relation to miR expression was studied. These results were analyzed by paired- and independent samples t-test, and non-parametric tests.

Results

miR-222 and miR-181a declined in PTC patients before and after surgery, significantly (P < 0.001 for both groups), with no significant difference in control group before and after surgery (P = 0.61 for miR-222 and P = 0.06 for miR-181a). The difference between the two groups, pre-and post-operation, was statistically significant (P = 0.01 for miR-222 and P < 0.001 for miR-181a). Comparing case and control groups, pre- and post-operatively, yielded no significant difference, in miR-155-5p levels (P = 0.61 and P = 0.53, respectively). Comparing PTC and control groups before surgery showed a significant difference (P = 0.01), while no significant difference was observed comparing them after surgery, in miR146-a (P = 0.27). Our results depicted a higher miR-155-5p and miR-146a expression before surgery than after it (P < 0.001 in both groups, for both miRs). We found a significant relationship between miR-222 and BRAFV600E mutation and significantly higher levels of miR-181a with increasing tumor size in PTC patients.

Conclusion

miR-222 showed overexpression in all PTC cases, which is indicative of a relation between miRNA and PTC. Also, comparing miR-181 and miR-146a showed a significant difference between cancerous and benign cases. miR-155-5p as an inflammatory factor, showed no significant changes, comparing two groups.

Does Primary Hyperparathyroidism Have an Association with Thyroid Papillary Cancer? A Retrospective Cohort Study

BACKGROUND

To investigate the relationship between primary hyperparathyroidism (pHPT) and papillary thyroid cancer (PTC).

METHODS

The perioperative findings of 275 patients with pHPT who underwent surgery between January 2014 and December 2017 were retrospectively reviewed. Thirty-one patients were diagnosed with pHPT and PTC concurrently. Pathology results and demographic findings of these patients were compared with 186 patients who underwent thyroidectomy and diagnosed with PTC at the same time interval.

RESULTS

The co-occurrence of pHPT and PTC was 11.3% (31/275). The median ages of the pHPT, pHPT + PTC, and PTC groups were 55, 57, and 50 years old, respectively (p < 0.001). The diameter of tumor was smaller in the pHPT + PTC group [median 7 mm (range 0.5-25 mm) vs. 15 mm (range 1-100 mm)], with higher rates of microcarcinomas (p < 0.001), than the patients in the PTC group. Examination of tumor morphology showed higher rates of tumor capsule invasion and multicentricity in the pHPT + PTC group than those in the isolated PTC group (p = 0.02, p = 0.04, respectively).

CONCLUSION

The pHPT + PTC group had significantly smaller tumor diameter than the PTC group. This result may support the idea that pHPT leads to overdiagnosis of PTC. However, observation of high rates of tumor capsule invasion and multicentricity in the pHPT + PTC group may suggest an associative etiology with more aggressive PTC.

Therapeutic Delivery of miR-143 Targeting Tumor Metabolism in Poorly Differentiated Thyroid Cancer Xenografts and Efficacy Evaluation Using 18F-FDG MicroPET-CT

Poorly differentiated thyroid carcinoma cells tend to be more aggressive and show enhanced glucose uptake which could be exploited for anti-cancer strategy. Previously, we identified hexokinase 2 (HK2) as a direct target of miR-143. In our current study, the effects of miR-143 on glucose metabolism and tumor biological behavior were investigated in FTC-133 cells which is a poorly differentiated thyroid carcinoma (PDTC). Additionally, tumor-bearing mice xenografts of PDTC were constructed, with encapsulated miR-143 agomir being administered intravenously. 18F-FDG microPET-CT scanning was used for the evaluation of therapeutic efficacy. The tumor-restrained effect of miR-143 was demonstrated in PDTC. Furthermore, microPET/CT imaging exhibited a reduction of 18F-FDG uptake in tumors, corresponding to the downregulated expression of HK2 in tissues. In summary, our results suggest that miR-143 can be an alternative treatment for PDTC and the specific assessment of therapeutic response to miR-143 can be achieved by 18F-FDG microPET/CT in advanced thyroid carcinoma xenografts.

Elevated levels of soluble PD-L1 are associated with reduced recurrence in papillary thyroid cancer

To date, no research evaluating the predictive capabilities of soluble programmed cell death-ligand 1 (sPD-L1) in thyroid cancer patients has been performed. We aimed to investigate the prognostic significance of sPD-L1 expression in papillary thyroid cancer (PTC) and to evaluate the association between sPD-L1 levels with tumoural PD-L1 expression and patient outcomes. Pre-treatment levels of serum and plasma sPD-L1 were measured by ELISA in 101 PTC patients. Tissue microarrays were stained with an anti-PD-L1 antibody, clone SP263 (Ventana). The median serum sPD-L1 concentration in PTC patients was significantly higher compared to healthy controls (P = 0.028). An increased incidence of extrathyroidal extension was significantly associated with an elevated serum sPD-L1 level (P = 0.015). Patients with high serum sPD-L1 levels had significantly shorter median disease-free survival (DFS) as compared to those with low sPD-L1 levels (P = 0.011). Following multivariate analysis, serum sPD-L1 was the only statistically significant predictor for DFS. Patients with both positive serum and tumoural PD-L1 expression had a significantly shorter DFS than those in any other subgroup (P = 0.007). Our study is the first to confirm that sPD-L1 concentration is significantly associated with patient outcome in PTC. Soluble PD-L1 may provide clinicians with a non-invasive biomarker that can lessen dependence on tissue biopsies and diagnose aggressive thyroid cancers at a more treatable stage.

In-Depth Proteomics Analysis to Identify Biomarkers of Papillary Thyroid Cancer Patients Older Than 45 Years with Different Degrees of Lymph Node Metastases

PURPOSE

Investigations of the molecular mechanisms underlying the metastatic phenotype of papillary thyroid cancer (PTC) and identification of novel candidate biomarkers to better predict PTC metastasis are urgently required.

EXPERIMENTAL DESIGN

Tandem mass tag-based quantitative proteomics approach is used to identify differentially expressed proteins (DEPs) in PTC tumorous tissues with different degrees of lymph node metastases (LNMs). Furthermore, DEPs and their clinical significance are analyzed in another independent Cancer Genome Atlas dataset.

RESULTS

The protein profiles among tumorous tissues with different degrees of LNMs are clearly distinguished, while the protein profiles in normal tissues are remarkably similar. DEPs in tumorous tissues are mostly enriched in the categories associated with pathological hallmarks of cancer, including extracellular matrix, metabolism, and cell growth. The expression patterns of six DEPs (LAMC2, LAMB3, ATP5A1, MYO1G, S100A4, and FAS) are confirmed by the Cancer Genome Atlas dataset. Additionally, the elevated expression of LAMC2 and MYO1G mRNA levels in tumorous tissues show a positive relationship with unfavorable variables, including larger tumor size, LNMs, high AJCC staging, BRAF^V600E mutation, and poor prognosis.

CONCLUSIONS AND CLINICAL RELEVANCE

LAMC2 and MYO1G are identified as potential candidate biomarkers for the prediction of PTC metastasis and prognosis.

Clonal analysis of early-stage bilateral papillary thyroid cancer identifies field cancerization

INTRODUCTION

Bilaterality is a newly identified indicator for aggressive tumor behavior and poor outcome in papillary thyroid cancer. However, the clonal origin of these bilateral tumors remains unclear.

METHODS

Here we analyzed 28 pairs of early-stage papillary thyroid cancers (stage I-II without extra-thyroidal extension, lymph node metastasis or distant metastasis) that underwent surgery at First Affiliated Hospital of Zhejiang University School of Medicine (Hangzhou, China). Genomic DNA was extracted from paraffin-embedded tissues after microdissection and analyzed for BRAF mutation and X-chromosome inactivation.

RESULTS

A total of 16 patients (16/28, 57.1%) harbored different BRAF status in bilateral tumors. Fourteen patients were available for X-chromosome inactivation assay and 10 of them achieved informative results. Bilateral tumors from four cases had distinct patterns of X-chromosome inactivation. Combining the results of X-chromosome inactivation and BRAF analysis, we demonstrated that at least 64.3% (18/28) cases harbored discordant X-chromosome inactivation or BRAF status, indicating their independent clonal origin in bilateral tumors.

CONCLUSIONS

The present study confirms "field cancerization" in early-stage bilateral thyroid cancers, suggesting that these subtype papillary thyroid cancers should be treated as independent and localized tumors.

Thyroid nodules: diagnosis and management

Thyroid nodules are common. Their importance lies in the need to assess thyroid function, degree of and future risk of mass effect, and exclude thyroid cancer, which occurs in 7-15% of thyroid nodules. There are four key components to thyroid nodule assessment: clinical history and examination, serum thyroid stimulating hormone (TSH) measurement, ultrasound and, if indicated, fine-needle aspiration (FNA). If the serum TSH is suppressed, a thyroid scan with ⁹⁹Tc can distinguish between a solitary hot nodule, a toxic multinodular goitre or, less commonly, thyroiditis or Graves' disease within a coexisting nodular thyroid. Scintigraphically cold nodules are evaluated in the same way as in the setting of normal or elevated serum TSH levels. Thyroid ultrasonography should be performed only for palpable goitre and thyroid nodules and by specialists with expertise in thyroid sonography. Routine thyroid cancer screening is not recommended, except in high risk individuals, as the detection of early thyroid cancer has not been shown to improve survival. FNA may be performed for nodules ≥ 1.0 cm depending on clinical and sonographic risk factors for thyroid cancer. FNA specimens should be read by an experienced cytopathologist and be reported according to the Bethesda Classification System. Molecular analysis of indeterminate FNA samples has potential to better discriminate benign from malignant nodules and thus guide management. Surgery is indicated for FNA findings of malignancy or indeterminate cytology when there is a high risk clinical context. Surgery may also be indicated for suspicion of malignancy; larger nodules, especially with symptoms of mass effect; and in some patients with thyrotoxicosis.

Expression of WD Repeat Domain 5 (WDR5) is Associated with Progression and Reduced Prognosis in Papillary Thyroid Carcinoma

Background

The WD repeat domain 5 (WDR5) is an essential component of methyltransferase complexes. The expression of WDR5 has been reported in several types of malignancy. This study aimed to investigate the expression of the WDR5 gene and protein in a human papillary carcinoma cell line in vitro, including the use WDR5 gene silencing, and the expression of the WDR5 protein in papillary thyroid carcinoma tissue, and clinicopathological characteristics including overall survival (OS).

Material/Methods

The role of WDR5 in proliferation and migration of the human papillary thyroid carcinoma cell line, KTC-1, was investigated using the cell counting kit-8 (CCK-8) assay and transwell assay after silencing WDR5 expression. Expression levels of WDR5 in 84 patients with papillary thyroid carcinoma were detected using immunohistochemistry. The correlation between WDR5 expression and clinicopathological features was analyzed using the chi-squared test. The prognostic role of WDR5 was evaluated by univariate analysis with the log-rank test, and by multivariate analysis with the Cox regression model.

Results

WDR5 expression promoted the proliferation and migration of the KTC-1 cells. In tumor tissue from patients with papillary thyroid carcinoma, low expression and high expression levels of WDR5 were found in 72.6% and 27.4%, respectively. Increased expression of WDR5 was significantly associated with lymphatic invasion and reduced survival rates. WDR5 expression was an independent negative prognostic biomarker.

Conclusions

Expression of WDR5 promoted cell proliferation and migration in vitro and was associated with reduced prognosis in patients with papillary thyroid carcinoma.

Antiproliferative Effects of Cynaropicrin on Anaplastic Thyroid Cancer Cells

BACKGROUND

The sesquiterpene lactone cynaropicrin, a major constituent of the artichoke leaves extracts, has shown several biologic activities in many preclinical experimental models, including anti-proliferative effects.

OBJECTIVE

Herein we evaluated the effects of cynaropicrin on the growth of three human anaplastic thyroid carcinoma cell lines, investigating the molecular mechanism underlying its action.

METHOD

MTT assay was used to evaluate the viability of CAL-62, 8505C and SW1736 cells, and flow cytometry to analyse cell cycle distribution. Western blot was performed to detect the levels of STAT3 phosphorylation and NFkB activation. Antioxidant effects were analyzed by measuring the reactive oxygen species and malonyldialdehyde dosage was used to check the presence of lipid peroxidation.

RESULTS

Viability of CAL-62, 8505C and SW1736 cells was significantly reduced by cynaropicrin in a dose- and time-dependent way, with an EC50 of about 5 µM observed after 48 h of treatment with the compound. Cellular growth inhibition was accompanied both by an arrest of the cell cycle, mainly in the G2/M phase, and the presence of a significant percentage of necrotic cells. After 48 h of treatment with 10 µM of cynaropicrin, a reduced nuclear expression of NFkB and STAT3 phosphorylation were also revealed. Moreover, we observed an increase in lipid peroxidation, without any significant effect on the reactive oxygen species production.

CONCLUSION

These results demonstrate that cynaropicrin reduces the viability and promotes cytotoxic effects in anaplastic thyroid cancer cells associated with reduced NFkB expression, STAT3 phosphorylation and increased lipid peroxidation. Further characterization of the properties of this natural compound may open the way for using cynaropicrin as an adjuvant in the treatment of thyroid cancer.

Impact of thyroiditis on 131I uptake during ablative therapy for differentiated thyroid cancer

CONTEXT

Differentiated thyroid cancer (DTC) is usually treated by thyroidectomy followed by radioiodine ablation and generally has a good prognosis. It may now be possible to limit the amount of treatment without impacting on efficacy. It is not known whether coexistent thyroiditis impacts on radioiodine uptake or on its potential efficacy, but this could provide a rationale for modification to current therapeutic protocols.

DESIGN

This was a retrospective cohort study of radioiodine uptake on imaging after radioiodine ablation for DTC in patients with and without concurrent thyroiditis. All patients with histologically confirmed DTC treated with radioiodine ablation after thyroidectomy in a single centre from 2012 to 2015 were included. The primary outcome assessed was the presence of low or no iodine uptake on post-ablation scan, as reported by a nuclear medicine physician blinded to the presence or absence of thyroiditis.

RESULTS

One hundred thirty patients with available histopathology results were included. Thyroiditis was identified in 42 post-operative specimens and 15 of these patients had low or no iodine uptake on post-ablation scan, compared to only 2 of 88 patients without thyroiditis (P < 0.0001) with further data analysis dividing the groups by ablation activity received (1100 MBq or 3000 MBq).

CONCLUSIONS

Concurrent thyroiditis may impair the uptake of radioactive iodine in management of DTC. Given that patients with DTC and thyroiditis already have a good prognosis, adopting a more selective approach to this step in therapy may be indicated. Large, longitudinal studies would be required to determine if omitting radioactive iodine therapy from those patients with concurrent thyroiditis has a measurable impact on mortality from thyroid cancer.

Comparing the Sensitivity and Specificity of Two-Dimensional Shear Wave Elastography and Fine Needle Aspiration in Determining Malignant Thyroid Nodules

Background

Malignancy in thyroid nodules is a common clinical problem, and epidemiological studies have shown that it is increasing. Since malignancy is a very important problem in treating patients and misdiagnosis leads to many physical and financial damages, the importance of diagnostic methods becomes more important. Hence, the aim of this study was to investigate the sensitivity and specificity of the two dimensional-shear wave elastography (2D-SWE) diagnostic method in comparison with fine-needle aspiration (FNA) in determining the malignant thyroid nodules.

Materials and Methods

This study is cross-sectional which was performed on 57 thyroid nodules are proven by conventional ultrasound. Afterward, 2D-SWE images were taken with the help of a superSonic ultrasound machine. Then, FNA was performed from the thyroid nodules and the specimens were evaluated in a single specialized thyroid pathology center. The results of conventional sonography and 2D-SWE were compared with histopathologic results as a gold standard method. The elasticity quantity was recorded by measuring the amount of the appropriate quantities by a recording machine and analyzed using the SPSS and MedCalc software.

Results

From 57 nodules studied, 50 nodules were evaluated with benign diagnosis and 7 nodules with the malignant diagnosis. Among all the parameters recorded by the machine, SWE. ratio provided the highest surface area under the curve and the highest sensitivity and specificity with 0.94, 100% and 84%, respectively, and a cut-off point of 1.7.

Conclusion

The 2D-SWE method and the conventional ultrasound can be good references for decision making about with the thyroid nodules.

Identifying gene modules of thyroid cancer associated with pathological stage by weighted gene co-expression network analysis

Thyroid cancer is the most common type of endocrine tumor. The TNM classification remains a standard for treatment determination and predicting prognosis in thyroid cancer. The genes modules associated with the progression of papillary thyroid carcinoma (PTC) were not clear. We applied a weighted gene co-expression network analysis (WGCNA) and differential expression analysis to systematically identified co-expressed gene modules and hub genes associated with PTC progression based on The Cancer Genome Atlas (TCGA) PTC transcriptome sequencing data. An independent validation cohort, GSE27155, was used to evaluate the preservation of gene modules. We identified two co-expressed genes modules associated with progression of PTC. Enrichment analysis indicated that the two modules were enriched in angiogenesis and extracellular matrix organization. DCN, COL1A1, COL1A2, COL5A2 and COL3A1 were hub genes in the co-expressed network. We systematically identified co-expressed gene modules and hub genes associated with PTC progression for the first time, which provided insights into the mechanisms underlying PTC progression and some potential targets for the treatment of PTC.

Clinicopathological predictors of occult lateral neck lymph node metastasis in papillary thyroid cancer: A meta-analysis

BACKGROUND

This meta-analysis aimed to identify the clinicopathological factors that could predict the risk of occult lateral neck lymph node metastasis (OLLNM) in N0/N1a papillary thyroid cancer (PTC).

METHODS

A literature search of PubMed, Web of Science, OvidSP, and Chinese National Knowledge Infrastructure databases was performed using relevant keywords. Specific odds ratios and confidence intervals were calculated.

RESULTS

The final analysis included 15 studies with a total of 5342 patients. OLLNM was found to be significantly associated with some clinicopathological features, including age <45 years, male sex, extrathyroidal extension, tumor location in the upper pole, tumor size >10 mm, positive central lymph node metastasis, number of central lymph node metastasis ≥3, and vascular invasion.

CONCLUSIONS

Fine-needle aspiration (FNA) cytology or FNA-Tg test might be an appropriate and reasonable intervention in the patients with N0/N1a PTC with an increased risk of OLLNM.

A novel microfluidic device capable of maintaining functional thyroid carcinoma specimens ex vivo provides a new drug screening platform

BACKGROUND

Though the management of malignancies has improved vastly in recent years, many treatment options lack the desired efficacy and fail to adequately augment patient morbidity and mortality. It is increasingly clear that patient response to therapy is unique to each individual, necessitating personalised, or 'precision' medical care. This demand extends to thyroid cancer; ~ 10% patients fail to respond to radioiodine treatment due to loss of phenotypic differentiation, exposing the patient to unnecessary ionising radiation, as well as delaying treatment with alternative therapies.

METHODS

Human thyroid tissue (n = 23, malignant and benign) was live-sliced (5 mm diameter × 350-500 μm thickness) then analysed or incorporated into a microfluidic culture device for 96 h (37 °C). Successful maintenance of tissue was verified by histological (H&E), flow cytometric propidium iodide or trypan blue uptake, immunohistochemical (Ki67 detection/ BrdU incorporation) and functional analysis (thyroxine [T4] output) in addition to analysis of culture effluent for the cell death markers lactate dehydrogenase (LDH) and dead-cell protease (DCP). Apoptosis was investigated by Terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL). Differentiation was assessed by evaluation of thyroid transcription factor (TTF1) and sodium iodide symporter (NIS) expression (western blotting).

RESULTS

Maintenance of gross tissue architecture was observed. Analysis of dissociated primary thyroid cells using flow cytometry both prior to and post culture demonstrated no significant change in the proportion of viable cells. LDH and DCP release from on-chip thyroid tissue indicated that after an initial raised level of release, signifying cellular damage, detectable levels dropped markedly. A significant increase in apoptosis (p < 0.01) was observed after tissue was perfused with etoposide and JNK inhibitor, but not in control tissue incubated for the same time period. No significant difference in Ki-67 positivity or TTF1/NIS expression was detected between fresh and post-culture thyroid tissue samples, moreover BrdU positive nuclei indicated on-chip cellular proliferation. Cultured thyroid explants were functionally viable as determined by production of T4 throughout the culture period.

CONCLUSIONS

The described microfluidic platform can maintain the viability of thyroid tissue slices ex vivo for a minimum of four days, providing a platform for the assessment of thyroid tissue radioiodine sensitivity/adjuvant therapies in real time.

Thyroid cancer risks among medical radiation workers in South Korea, 1996-2015

BACKGROUND

Thyroid cancer rates, especially among children, are known to be increased by radiation exposure. However, little is known about the impact of chronic low-dose radiation exposure on thyroid cancer risk in adulthood. This study examined radiation effects on thyroid cancer rates as well as an overall evaluation of thyroid cancer risk among medical radiation workers.

METHODS

Data on all diagnostic medical radiation workers enrolled in the national dosimetry registry between 1996 and 2011 were linked with the cancer registry data through 2015. Standardized incidence ratios (SIRs) were used to compare the observed cancer incidence rates in this population to those for the general population while internal comparisons were used to estimate relative risks (RRs) for occupational history and excess relative risks (ERRs) were used to quantify the radiation dose-response relationship.

RESULTS

Overall, 827 thyroid cancer cases were reported among 93,922 medical radiation workers. Thyroid cancer SIRs were significantly higher than expected for both men (SIR 1.72, 95% confidence interval [CI] 1.53 to 1.91) and women (SIR 1.18, 95% CI 1.08 to 1.28). However, RRs for thyroid cancer by job title and duration of employment showed no particular pattern among diagnostic medical radiation workers. There were no indications of a significant dose effect on thyroid cancer rates for either men (ERR/100 mGy 0.07, 95% CI -0.38 to 0.53) or women (ERR/100 mGy -0.13, 95% CI -0.49 to 0.23). The findings were similar for different job titles or when limited to workers employed for at least one year.

CONCLUSIONS

While thyroid cancer incidence rates among Korean medical radiation workers were somewhat higher than those in the general population, there was no significant evidence that this increase was associated with occupational radiation dose. Additional follow-up together with consideration of other risk factors should provide useful information on thyroid cancer rates in this cohort.

Transoral Endoscopic Thyroidectomy for Thyroid Cancer

The prevalence of low-risk differentiated thyroid cancer (DTC) is dramatically increasing because of superior diagnostic imaging technologies. Remote-access endoscopic thyroidectomy is becoming more popular for the lack of a noticeable neck scar. Transoral endoscopic thyroidectomy, vestibular approach (TOETVA) is the only technique that could be called a true scarless surgery; however, there is a scarcity of long-term studies about its safety and feasibility. Because thyroid cancer is a slow-growing lesion, with adequate follow-up and surveillance, TOETVA is a surgical procedure for the management of low-risk DTC without any difference of surgical and oncological outcome.

Understanding Pathways to the Diagnosis of Thyroid Cancer: Are There Ways We Can Reduce Over-Diagnosis?

BACKGROUND

The incidence of thyroid cancer has rapidly increased, and ecological evidence suggests this is due in some part to over-diagnosis. Understanding pathways to diagnosis could help determine whether unnecessary diagnosis can be avoided.

METHODS

A population-based sample (n = 1007) of thyroid cancer patients diagnosed between July 2013 and August 2016 was recruited from Queensland, Australia (response rate 67%). Information from structured telephone interviews was used to describe diagnostic pathways for thyroid cancer, to investigate factors associated with diagnostic pathways, and to assess the most prevalent modes of diagnoses by which the lowest-risk, potentially over-diagnosed thyroid cancers (intrathyroidal microcarcinomas) are detected.

RESULTS

Only 38% of participants presented with symptoms potentially related to thyroid cancer. Older age at diagnosis was associated with a lower prevalence of symptomatic diagnosis (prevalence ratio [PR] = 0.46 [confidence interval (CI) 0.31-0.68] for 70-79 vs. <30 years), as was frequent medical contact, while living in rural/regional areas was associated with a higher prevalence of symptomatic diagnosis (PR = 1.17 [CI 1.00-1.37] for rural/regional areas vs. major cities). Symptomatic diagnosis also occurred more for those whose tumors had adverse histopathological features (larger size, lymph node involvement, lymphovascular invasion). The likelihood of diagnosis of intrathyroidal microcarcinomas was greatest for those having surgical resection or monitoring for benign thyroid disease (PR = 3.87 [CI 2.81-5.32] and PR = 2.21 [CI 1.53-3.18], respectively).

CONCLUSIONS

A minority of newly detected thyroid cancer cases were diagnosed because of symptoms. Access to medical care and factors related to cancer aggressiveness were associated with how diagnoses occurred. The likelihood of diagnosing the lowest-risk thyroid cancers was higher in situations related to management of other thyroid conditions. Adherence to thyroid management guidelines could reduce some thyroid cancer over-diagnosis, but ultimately better diagnostic tools are needed to differentiate between indolent cancers and those of clinical significance.

Human telomerase reverse transcriptase in papillary thyroid cancer: gene expression, effects of silencing and regulation by BET inhibitors in thyroid cancer cells

PURPOSE

Mutations in TERT promoter have been detected in the more aggressive papillary thyroid cancers (PTCs). To elucidate the role of TERT as an eligible molecular target in these tumors, the expression of hTERT was analyzed in a series of PTCs and the effects of both pharmacological and RNA-interference-induced hTERT silencing were investigated in two human PTC cell lines (K1 and BCPAP).

METHODS

The expression levels of hTERT mRNA and protein were evaluated by real-time PCR and western blot assays, respectively. Effects of hTERT silencing on PTC cell lines were analyzed by MTT, migration and western blot assays. Pharmacological inhibition of hTERT was performed using two bromodomain and extra-terminal (BET) inhibitors, JQ1 and I-BET762.

RESULTS

hTERT expression results increased in 20 out of 48 PTCs, including tumors either positive or negative for the presence of hTERT promoter and/or BRAF mutations. In K1 and BCPAP cells, hTERT silencing determined a reduction in cell viability (~50% for K1 and ~70%, for BCPAP, vs control) and migration properties that were associated with a decrease of AKT phosphorylation and β-Catenin expression. Moreover, hTERT mRNA levels were down-regulated by two BET inhibitors, JQ1 and I-BET762, which at the same dosage (0.5 and 5 µM) reduced the growth of these thyroid cancer cells.

CONCLUSIONS

These findings demonstrate that hTERT may represent an excellent therapeutic target in subgroups of aggressive PTCs.

Metabolic Obesity Phenotypes and Thyroid Cancer Risk: A Cohort Study

BACKGROUND

No cohort studies have evaluated the effect of obesity on the incidence of thyroid cancer according to metabolic health status. Therefore, this study examined the association of body mass index (BMI) and metabolic health status with thyroid cancer risk.

METHODS

A cohort study was performed involving 255,051 metabolically healthy (MH) and metabolically unhealthy (MUH) adults free of thyroid cancer at baseline who were followed for a median of 5.3 years. A parametric proportional hazard model was used to estimate the adjusted hazard ratio (aHR) and confidence interval (CI).

RESULTS

During 1,402,426.3 person-years of follow-up, 2927 incident thyroid cancers were identified. Among men, the multivariable aHR for thyroid cancer comparing obesity, defined as a BMI ≥25 kg/m², with a BMI of 18.5-22.9 kg/m² was 1.47 [CI 1.12-1.93] in MH individuals, whereas the corresponding HR in MUH individuals was 1.26 [CI 1.03-1.53]. Among women, the corresponding HR in MH individuals was 1.05 [CI 0.80-1.36], whereas the corresponding HR in MUH individuals was 1.43 [CI 1.22-1.69]. Increasing quartiles of waist circumference were positively associated with risk of thyroid cancer in MUH men and women (p for trend <0.005) but not in MH individuals.

CONCLUSIONS

In both MH and MUH men, obesity was associated with an increased risk of incident thyroid cancer, indicating excessive adiposity per se as an independent risk factor for thyroid cancer. Conversely, women with MUH obesity but not MH obesity were found to have an increased risk of thyroid cancer, indicating that obesity with accompanying metabolic abnormalities may affect thyroid cancer risk in women.