Prognostic markers in well differentiated papillary and follicular thyroid cancer (WDTC)

Radioactive iodine refractoriness in Middle Eastern differentiated thyroid cancer: clinical outcome and risk factor analysis

Background

Radioactive iodine refractory differentiated thyroid cancer (RAIR-DTC) has received increasing attention due to its poor prognosis. However, outcomes may vary among patients with RAIR-DTC. The role of clinico-pathological and molecular prognostic factors in survival remains controversial, resulting in difficulty in selecting patients for new targeted therapies. We assessed mortality rate and DTC-specific survival in Middle Eastern RAIR-DTC to identify prognostic factors associated with survival.

Methods

This single center, retrospective study enrolled 268 patients with RAIR-DTC. Mortality rate and DTC-specific survival were analyzed to identify prognostic factors related to survival. Univariate and multivariate analysis were performed using Cox proportional hazards model.

Results

Of the 268 cases of RAIR-DTC, 40.3% (108/268) had absent 131I uptake (either on diagnostic or post-therapy whole body scan), 15.3% (41/268) had progressive disease (PD) despite 131I, 7.5% (20/268) had persistent disease despite cumulative activity of I131 of >600 mCi and 36.9% (n=99/268) developed distant metastasis. On multivariate analysis, age (more than 45 years), presence of metastatic disease and tumors harboring telomerase reverse transcriptase (TERT) promoter mutations were independent prognostic factors for poor DTC-specific survival. Subjects were divided into 3 groups according to the number of risk factors; low risk (no risk factors); intermediate (≤ 2 risk factors); and high risk (all the 3 risk factors). Ten-year DTC-specific survival rates in low, intermediate and high-risk groups were 100.0%, 92.9% and 53.6%, respectively.

Conclusions

The contribution of age greater than 45 years to RAIR-DTC mortality is impactful. Older age, presence of distant metastasis and TERT mutations could be used as early predictors of RAIR-DTC cases. The identification of prognostic factors for poor survival in RAIR-DTC may improve the selection of patients for more personalized surveillance and therapeutic modalities.

BRAF V600E mutation in papillary thyroid microcarcinoma: is it a predictor for the prognosis of patients with intermediate to high recurrence risk?

OBJECTIVE

The BRAFV600E mutation is the universal genetic mutation in papillary thyroid microcarcinoma (PTMC). The present study is to estimate the role of the BRAFV600E mutation in the clinical outcome of PTMC with intermediate to high recurrence risk after radioactive iodine (RAI) therapy, which is considered to be an indolent tumor.

METHODS

We conducted a single-center retrospective study. Between May 2016 and March 2019, PTMC patients with known BRAFV600E status who received RAI therapy were reviewed at the Second Hospital of Shandong University. Treatment and follow-up were defined according to criteria used in the 2015 ATA guidelines. The association between the BRAFV600E mutation and clinicopathological characteristics, response to RAI therapy, and recurrence after a period of follow-up were analyzed. Propensity score matching (PSM) and logistic regression were used to control confounding variables.

RESULTS

Of the 322 patients with intermediate to high recurrence risk in PTMC, the mean age of the patients were 43.7 ± 12.2 years, and 72.1% were women. BRAFV600E mutation was found in 64.9% (209/322). After PSM, 112 pairs of patients were matched, and except for multifocality (P = 0.001), extrathyroidal invasion (P = 0.003) and tumor size (P = 0.03), there was no significant difference in all baseline characteristics between the two groups. An excellent response (ER) to RAI therapy was observed in 273 patients (84.7%). At the end of the study, 17(5.2%) and 6(1.8%) patients showed structural incomplete response (SIR) and biochemical incomplete response (BIR) status. The proportion of patients who achieved ER status in the BRAFV600E mutation positive and negative groups was 86.6% and 81.4%, respectively. Kaplan-Meier analyses showed that the BRAFV600E mutation was not related to lower ER reached time. The median follow-up was 51 months.

CONCLUSIONS

We found the BRAFV600E mutation was associated with multifocality, extrathyroidal invasion, and tumor size in papillary thyroid microcarcinoma. However, the BRAFV600E mutation had no significant association with clinical outcomes in patients with intermediate to high recurrence risk after RAI therapy. Furthermore, the extra-thyroid uptake results and distant metastasis had been proven to be independent factor predicting the clinical response.

REGISTRATION NUMBER

ChiCTR2200062911.

Prognosis and influencing factors of follicular thyroid cancer

OBJECTIVES

Follicular thyroid cancer (FTC) is prone to distant metastasis, and patients with distant metastasis often have poor prognosis. In this study, the impact of metastasis and other relevant factors on the prognosis of follicular thyroid carcinoma was examined.

METHODS

This was a retrospective study. Data were obtained from Zhejiang Cancer Hospital, Sun Yat-sen University Cancer Center and Hangzhou First People's Hospital affiliated with Zhejiang University School of Medicine, from January 2009 to June 2021 for 153 FTC patients. The patients were assigned into three groups according to their distant metastasis: distant metastasis at initial diagnosis (M1), distant metastasis during follow-up (M2), and no evidence of distant metastasis over the course of the study (M0). Data were collected and summarized on clinical data, laboratory parameters, imaging features, postoperative pathologic subtypes, and metastases. The Cox proportional hazard model was used to perform the univariate and multivariate analysis. Kaplan-Meier curves were used to evaluate cancer-specific survival (CSS).

RESULTS

Based on metastasis, the patients were assigned into three groups, including 31 in the M1 group, 15 in the M2 group, and 107 in the M0 group. These individuals were followed up for an average of 5.9 years, and the group included 46 patients with distant metastasis (31 confirmed at diagnosis and 15 found during follow-up). Univariate Cox regression analysis showed that age, Hashimoto's thyroiditis (HT), surgery method, postoperative adjuvant therapy, histologic subtype, nodule size, calcification, TSH, and distant metastasis all impacted prognosis. Multivariate Cox regression analysis suggested that histologic subtype (widely invasive; HR: 7.440; 95% CI: 3.083, 17.954; p < 0.001), nodule size (≥40 mm; HR: 8.622; 95% CI: 3.181, 23.369; p < 0.001) and distant metastasis (positive; HR: 6.727; 95% CI: 2.488, 18.186; p < 0.001) were independent risk factors affecting the prognosis of follicular thyroid cancer.

CONCLUSIONS

Histologic subtype, nodule size, and distant metastasis are important risk factors for the prognosis of follicular thyroid cancer. Patients with metastatic follicular thyroid cancer have a poor prognosis, especially with metastasis at the time of initial diagnosis. As a result, this group of patients requires individualized treatment and closer follow-up.

Risk factors for death of follicular thyroid carcinoma: a systematic review and meta-analysis

BACKGROUND

There are conflicting reports on the factors that increase the likelihood of patients dying from follicular thyroid carcinoma (FTC). Therefore, it is critical to identify risk factors of patients with FTC. This study aimed to identify the factors that increase the risk of death of patients with FTC and help clinicians make better treatment and follow-up decisions.

METHODS

A systematic literature review was conducted in PubMed and Web of Science databases for relevant studies published before January 31, 2023. Their reference lists were also analyzed. Two reviewers extracted data and evaluated the quality of eligible studies independently. Studies on patients who had open thyroidectomy procedures with or without neck dissection were included in this review. The RevMan 5.3 software was used to analyze the data.

RESULTS

This meta-analysis included thirteen studies with a total of 2075 patients. The following variables were associated with an increased risk of death in FTC patients: age > 45 years, male, tumor diameter > 4 cm, multifocality, extrathyroidal extension (ETE), widely invasive (WI), cervical lymph node metastasis (CLNM), distant metastases (DM) and non-radical resection tumor. Lobectomy and no radioactive iodine (RAI) treatment was not associated with the death of FTC patients.

CONCLUSION

Clinicians should pay closer attention to the following significant risk factors associated with the death of FTC patients: age (> 45), male, multifocality, tumor diameter > 4 cm, ETE, WI, non-radical resection tumor, CLNM, and DM. Individualized initial treatment and close follow-up are needed FTC patients who have these risk factors.

A Nod to the Nodes: An Overview of the Role of Central Neck Dissection in the Management of Papillary Thyroid Carcinoma

Lymph node metastasis in thyroid cancer is common and associated with an increased risk of locoregional recurrence (LRR). Although therapeutic central neck dissection is well established, prophylactic central node dissection (pCND) for microscopic occult nodal involvement is controversial and recommendations are based on low-level evidence. The potential benefits of pCND such as reducing LRR and re-operation, refining staging, and improving surveillance are enthusiastically debated and the decision to perform pCND must be weighed up against the increased risks of complications.

Increased expression of GPX4 promotes the tumorigenesis of thyroid cancer by inhibiting ferroptosis and predicts poor clinical outcomes

BACKGROUND

Ferroptosis plays a critical role in suppressing cancer progression, and its essential regulator is glutathione peroxidase 4 (GPX4). High GPX4 expression can inhibit accumulation of iron, thus suppressing ferroptosis. However, its function in thyroid cancer has not been fully illuminated. Here, we explore the effect of GPX4 on thyroid cancer tumorigenesis and prognosis.

METHODS

Based on The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases, GPX4 expression was investigated in cancer tissues and adjacent tissues. We determined the biological functions of GPX4-associated differentially expressed genes (DEGs) by using the "clusterProfiler" R package. In addition, the predictive value of GPX4 in thyroid cancer was assessed by using Cox regression analysis and nomograms. Finally, we conducted several in vitro experiments to determine the influence of GPX4 expression on proliferation and ferroptosis in thyroid cancer cells.

RESULTS

GPX4 expression was obviously elevated in thyroid cancer tissues compared with normal tissues. Biological function analysis indicated enrichment in muscle contraction, contractile fiber, metal ion transmembrane transporter activity, and complement and coagulation cascades. GPX4 overexpression was associated with stage T3-T4 and pathologic stage III-IV in thyroid cancer patients. Cox regression analysis indicated that GPX4 may be a risk factor for the overall survival of thyroid cancer patients. In vitro research showed that knockdown of GPX4 suppressed proliferation and induced ferroptosis in thyroid cancer cells.

CONCLUSIONS

GPX4 overexpression in thyroid cancer might play an essential role in tumorigenesis and may have prognostic value for thyroid cancer patients.

Surgical treatment and prognosis values of extranodal extension to recurrent laryngeal nerve in papillary thyroid carcinoma

PURPOSE

Recurrent laryngeal nerve (RLN) invasion by extranodal extension (ENE) is a rare condition that may occur in papillary thyroid cancer (PTC), and it has never been characterised in the literature.Our research aims to investigate the clinical significance of ENE to RLN including its effect on vocal cord function, relationship with the aggressive behaviour of PTC, and optimal surgical methods.

METHODS

A total of 3119 patients, including 2868 patients without RLN invasion, 251 patients with RLN invasion [categorised into the ENE invasion group (n = 55) and extrathyroidal extension (ETE) invasion group (n = 196)] were analyzed retrospectively. Data on clinicopathological characteristics, vocal cord paralysis (VCP), postoperative complications, surgical methods, rates of recurrence and metastasis were collected. Predictive disease-free survival (DFS) was analysed using the Kaplan-Meier method.

RESULTS

The ENE invasion group showed a similar rate of VCP and DFS compared with the ETE invasion group (P = 0.15, P = 0.38, respectively). Sharp separation applied on the invaded nerves preserves the visual integrity of the RLN without significantly reducing the DFS (P > 0.05). ETE or ENE to RLN, lymph nodes metastasis (LNM), and T4 stage were independent factors for total recurrence [P = 0.04, hazard ratio (HR), 1.97 (1.04-3.75); P = 0.00, HR, 4.63 (2.24-9.54); P = 0.00, HR, 3.63 (1.94-6.77); P = 0.00, HR, 6.1 (3.24-11.50)]. RLN invasion, both by ETE or ENE, was significantly associated with reduced DFS (P = 0.00; P = 0.00, respectively).

CONCLUSIONS

ENE to RLN, while rare, has not previously been well-studied. Our interesting premise and important findings including ENE to RLN has the same poor prognostic impact on recurrence as does invasion of the RLN by ETE and surgical management for the invaded RLN that preserves its visual integrity without compromising DFS. Those novel findings indicate that ENE to RLN could be considered as an additional factor beyond post-operative disease status and risk stratification, and it would be a valuable addition to further individualise treatment/surveillance for PTC.

Clinical significance of extrathyroidal extension to major vessels in papillary thyroid carcinoma

PURPOSE

Gross extrathyroidal extension (gETE) into major vessel is considered the most advanced stage of the locally advanced papillary thyroid cancer (PTC). Surgical intervention may not benefit some patients at this disease stage or even result in intraoperative death due to massive hemorrhage; however, it is still considered an effective strategy for most cases. The lack of description for this challenging invasion in PTC warrants detailed characterization of its pattern, risk factors, optimal surgical method, and prognostic value.

METHODS

In total, 3127 patients diagnosed as having PTC were enrolled and categorized into two the following groups, namely the major vessel invasion (MVI) group (n = 30) and the control group (n = 3097). Data regarding clinicopathological and demographic characteristics, vascular invasion sites, postoperative complications, locoregional recurrence, distant metastasis, and surgical strategies were collected. Predictive disease-free survival (DFS) was also compared between the two groups.

RESULTS

MVI was independently associated with invasion of the esophageal extension, age < 55 years, tumor size > 1 cm, lateral lymph node metastasis, and distant metastasis (P = 0.00; P = 0.01; 0.05; P = 0.00; P = 0.00, respectively). The difference in the predictive DFS between the two groups was significant (P = 0.00), and the difference remained significant even in patients with ETE when compared with patients without ETE (P = 0.00). Additionally, predictive DFS did not differ significantly between patients who received vessel repairment and those who received vessel resection (P = 0.28).

CONCLUSIONS

This study first characterized the gross MVI pattern exhibited by PTC and the risk factors for MVI. Additionally, it demonstrated the DFS of patients with PTC. Extensive gross MVI significantly worsened the biological characteristics of PTC. Regardless of the high risk and difficulty of the operation, patients still benefited from the surgical intervention, and vessel repairment may be the optimal surgical strategy.

The Role of Prophylactic Cervical Lymph Node Dissection with Total Thyroidectomy in Prevention Recurrence of Papillary Thyroid Carcinoma

AIM: It is assess benefit prophylactic selective unilateral cervical lymph node (LN) dissection with total thyroidectomy for patients who have papillary thyroid carcinoma (PTC) and negative cervical lymph nodes metastasis and determination recommended risk factors for such surgery. METHODS: This was a prospective study, 60 patients with PTC investigated by Fine needle aspiration, ultrasonography to support diagnosis patients with PTC, and negative lymph node metastasis. Nineteen patients are excluded from the entire 60 patients; remaining 41 patients are submitted to a total thyroidectomy and prophylactic selective one side ipsilateral lateral and central lymph nodes dissection (level II, III, IV, and V). Then, follow-up 2 years for all patients, postoperatively, for detection PTC recurrence. RESULTS: The result shows that from the total 41 patients, two groups are positive and negative lymph nodes metastasis 24.4% (10) and 75.6% (31), respectively, positive lymph nodes metastasis is presented more in male 7 (70%) with significant difference (p = 0.03) and age groups <55 years old 6 (60%) with insignificant association (p = 0.413). Thyroid nodular size (>1 cm) and multiple nodules presented more in positive lymph nodes metastasis with significant difference in both. Multivariate binary logistic regression, sex, thyroid multinodularity, and thyroid nodule size were insignificant relationship of prediction of lymph nodes metastasis. CONCLUSION: Prophylactic cervical LN dissection with total thyroidectomy for patients with PTC and negative cervical lymph nodes metastasis has beneficial role in preventing recurrence of PTC. Risk factors such as male gender, thyroid multinodularity (multiple nodule), and their size (>1 cm) have role in increasing chance of occurrence of cervical LN metastasis.

Analysis of anti-apoptotic PVT1 oncogene and apoptosis-related proteins (p53, Bcl2, PD-1, and PD-L1) expression in thyroid carcinoma

BACKGROUND

An aberrant expression of long non-coding RNA PVT1 has been associated with apoptosis in various cancer types. We aimed to explore the PVT1 and four apoptosis-related proteins (p53, Bcl2, and PD-1/PD-L1) signature in thyroid cancer (TC).

METHODS

The PVT1 expression level was measured in 64 FFPE TC paired samples by real-time quantitative PCR. Overall and stratified analyses by different clinicopathological features were done. The apoptotic proteins were evaluated by immunohistochemistry staining.

RESULTS

Overall analysis showed significant PVT1upregulation in TC tissues (p < 0.001). Similarly, subgroup analysis by BRAFV600E mutation showed consistent results. Lower expression of p53 was associated with mortality (p = 0.001). Bcl2 overexpression was associated with greater tumor size (p = 0.005). At the same time, HCV-positive cases were associated with repressed Bcl2 expression levels (54.3% in HCV-negative vs. 6.9% in HCV-positive cases, p = 0.011). PD-1 expression was associated with lymph node metastasis (p = 0.004). Enhanced PD-L1 expression in the tumor was associated with a higher tumor stage, lymphovascular invasion, and mortality risk. Kaplan-Meier curves for overall survival showed that low p53 and high PD-L1 expressions were associated with lower survival time. The p53-positive staining is associated with a 90% decreased mortality risk (HR = 0.10, 95%CI = 0.02-0.47, p = 0.001), while patients with high PD-L1 were five times more likely to die (HR = 4.74, 95%CI = 1.2-18.7, p = 0.027).

CONCLUSION

Our results confirm the upregulation of PVT1 in TC. The apoptosis-related proteins (p53, Bcl2, and PD-1/PD-L1) showed different prognostic utility in TC patients; in particular, low p53 and high PD-L1 expressions associated with low survival times. Further large-scale and mechanistic studies are warranted.

Long-Term Outcome of Differentiated Thyroid Cancer Patients-Fifty Years of Croatian Thyroid Disease Referral Centre Experience

Background: Indolent nature but a high incidence of differentiated thyroid cancer (DTC) remains a challenge for optimizing patient care. Therefore, prognostic factors present valuable information for determining an adequate clinical approach. Methods: This study assessed prognostic features of 1167 papillary (PTC) and 215 follicular (FTC) thyroid cancer patients that had undergone surgery between 1962 and 2012, and were followed-up up to 50 years in a single institution, till April 2020. Age, gender, tumor size, presence of local and distant metastases at presentation, extrathyroidal extension, disease recurrence, and cancer-specific survival were evaluated. Results: In multivariate analysis, factors affecting the worse outcome were age (p = 0.005), tumor size (p = 0.006), and distant metastases (p = 0.001) in PTC, while extrathyroidal extension (p < 0.001), neck recurrence (p = 0.002), and distant metastases (p < 0.001) in FTC patients. Loco-regional recurrence rate was 6% for PTC and 4.7% for FTC patients, while distant metastases were detected in 4.2% PTC and 14.4% of FTC patients. The 10-year cancer-specific survival rates for PTC and FTC were 98.6% and 89.8%, respectively (p < 0.001). Conclusions: Negative prognostic factors, besides distant metastases, were older age and greater tumor size in PTC, and extrathyroidal extension and neck recurrence in FTC patients. The recurrence and mortality rates were very low.

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.

Surgery and Radioactive Iodine Therapeutic Strategy for Patients Greater Than 60 Years of Age with Differentiated Thyroid Cancer

PURPOSE

The purpose of the current study was to determine whether older patients with differentiated thyroid cancer (DTC) who received surgical treatment had a better cause-specific survival (CSS) than patients who were recommended surgery, but declined, and whether patients who underwent postoperative RAI-131 therapy had an impact on CSS based on TNM staging and number of lymph node metastases for all total or near-total thyroidectomy patients. Patients and Methods: This retrospective, population-based study analyzed the clinical data of 162 DTC patients from signal institution in China and 26,487 cases from the Surveillance, Epidemiology, and End Results (SEER) program registry. The patients were divided into two groups (underwent surgery and surgery recommended, but not performed) in the SEER cohort. Furthermore, patients were grouped as follows: T4; N1b; M1; T1-3N0-1a; specific number of lymph node metastases; and total or near-total thyroidectomy. Results: The 120-month cause-specific survival (CSS) rate of women and men showed a gradual declining trend from 60-64 to ≥80 years of age in the group that underwent surgery. The CSS rate of women and men showed a marked downward and irregular trend with an increase in age in the recommended, but no surgery group in the SEER cohort. Univariate analysis indicated that the surgery group had a higher 120-month CSS in women in most stages and men, compared with the no surgery group in the SEER cohort. The analysis of the SEER cohort showed that RAI-131 therapy was associated with an improved 80-month CSS in T4/N1b/M1 women (P < 0.0183) and men (P < 0.0011). However, there were no CSS differences between the RAI-131 therapy and the no-RAI-131 group for the patients with T4/N1b/M1 (AJCC 7th) thyroid cancer in the Chinese cohort. There was no CSS difference in women or men between the T1-3N0 and T1-3N1a patients in the SEER cohort. And similar findings were observed in T1-3N1a patients in the Chinese cohort. There was no statistical difference between the two subgroups. Conclusions: Surgical treatment should be recommended for elderly DTC patients because surgery can lead to a better CSS. High-risk patients achieve a higher benefit-to-risk ratio with RAI-131 therapy. To avoid the adverse effects associated with RAI-131 therapy, a multidisciplinary discussion should be arranged for intermediate- and low-risk patients.

A Novel Role of Galectin-3 and Thyroglobulin in Prognosis and Differentiation of Different Stages of Thyroid Cancer and Elucidation of the Potential Contribution of Bcl-2, IL-8 and TNF-α

Thyroid cancer is among the most prevalent cancers with different types and stages. New markers are required for the prognosis and diagnosis of the disease. The present study aimed to detect the role of new markers, including galectin-3 (Gal-3) and thyroglobulin (TG), in the prognosis and staging of thyroid cancer. The study also investigated the potential apoptotic and inflammatory mechanisms involved in thyroid cancer through the determination of B-cell lymphoma 2 (Bcl-2), interleukin-8 (IL-8) and tumor necrosis factor α (TNFα) during the different stages of the cancer using a series of molecular methods. Histopathological and immunohistochemical examinations were also performed. A total of 300 subjects were classified into: 100 normal healthy subjects matched in age and sex, 100 patients with thyroid carcinoma stage I (T1N0M0) and 100 patients with thyroid carcinoma stage 2 (T2N1M1). Interestingly, the present study revealed a significant increase in the levels of TG and Gal-3 in thyroid cancer patients compared to the control group. Furthermore, the levels of Bcl-2, IL-8 and TNF-α significantly increased in the patient serum. The histopathological examination and immunohistochemical observations confirmed the molecular and hematological findings. Collectively, the present study concluded that serum TG and Gal-3 could be useful markers in the prognosis and staging of patients with thyroid cancer. Furthermore, the determination of Bax, Bcl-2, IL-8 and TNF-α levels constitute a major important marker for investigation of the mechanisms of apoptosis and inflammation in thyroid cancer. To our knowledge, this is the first study that used both galectin-3 and TG as tumor markers in the prognosis and differentiation between the different stages of cancer.

Correlation between Pre-Operative 25-Hydroxyvitamin D Levels and Poor Prognostic Factors for Papillary Thyroid Cancer

PURPOSE

To evaluate the relationship between pre-operative 25-hydroxyvitamin D (25 (OH) D) levels and poor prognostic factors for papillary thyroid cancer (PTC).

METHODS

A total of 1161 patients diagnosed with PTC were analyzed retrospectively. The patients were categorized .based on their pre-operative 25 (OH) D levels into three groups: the severe vitamin D deficiency (VDD) group (25 (OH) D < 10 ng/mL), moderate VDD group (20 ng/mL > 25 (OH) D ≥ 10 ng/mL), and control group (25(OH)D ≥ 20 ng/mL) Differences in the demographic and clinicopathological characteristics among the three groups were analyzed. Linear and logistic regression analyses were also performed to determine the effect of 25 (OH) D levels on the established poor prognostic factors for PTC.

RESULTS

We observed a negative correlation between 25 (OH) D levels and tumor size (r = -0.067, P = 0.049). Severe VDD and moderate VDD were independently associated with lymph node metastasis and distant metastasis diagnosed during surgery (P = 0.00, odds ratio (OR) = 4.11; P = 0.00, OR = 3.33, respectively). After adjusting parameters such as sex, age, body mass index, and thyroid-stimulating hormone (TSH) levels, severe VDD and moderate VDD were found to be closely associated with advanced cancer stage (stage III or IV) (P = 0.018, OR = 3.02; P = 0.041, OR = 3.60, respectively). Additionally, a significant correlation (P = 0.007) was observed between the pre-operative 25 (OH) D and TSH levels.

CONCLUSION

25 (OH) D levels were significantly associated with certain poor prognostic factors for PTC, including larger tumor diameter and the occurrence of lymph node metastasis. More prospective studies are needed to evaluate whether the assessment and supplementation of vitamin D contributes to the pre-operative management of patients with PTC.

Androgen Activity Is Associated With PD-L1 Downregulation in Thyroid Cancer

Thyroid cancer is the most prevalent endocrine malignancy in the United States with greater than 53,000 new cases in 2020. There is a significant gender disparity in disease incidence as well, with women developing thyroid cancer three times more often than men; however, the underlying cause of this disparity is poorly understood. Using RNA-sequencing, we profiled the immune landscape of papillary thyroid cancer (PTC) and identified a significant inverse correlation between androgen receptor (AR) levels and the immune checkpoint molecule PD-L1. The expression of PD-L1 was then measured in an androgen responsive-thyroid cancer cell line. Dihydrotestosterone (DHT) treatment resulted in significant reduction in surface PD-L1 expression in a time and dose-dependent manner. To determine if androgen-mediated PD-L1 downregulation was AR-dependent, we treated cells with flutamide, a selective AR antagonist, and prior to DHT treatment to pharmacologically inhibit AR-induced signaling. This resulted in a > 90% restoration of cell surface PD-L1 expression, suggesting a potential role for AR activity in PD-L1 regulation. Investigation into the AR binding sites showed AR activation impacts NF-kB signaling by increasing IkBα and by possibly preventing NF-kB translocation into the nucleus, reducing PD-L1 promoter activation. This study provides evidence of sex-hormone mediated regulation of immune checkpoint molecules in vitro with potential ramification for immunotherapies.

Imaging of the Thyroid: Practical Approach

Imaging evaluation of the thyroid gland spans a plethora of modalities, including ultrasound imaging, cross-sectional studies, and nuclear medicine techniques. The overlapping of clinical and imaging findings of benign and malignant thyroid disease can make interpretation a complex undertaking. We aim to review and simplify the vast current literature and provide a practical approach to the imaging of thyroid disease for application in daily practice. Our approach highlights the keys to differentiating and diagnosing common benign and malignant disease affecting the thyroid gland.

Predicting distant metastatic disease in differentiated thyroid cancer: a matched case-control study

BACKGROUND

The occurrence of distant metastasis (DM) is the most important prognostic factor influencing survival outcomes in differentiated thyroid cancer (DTC). Identifying patients who are likely to develop DM and offering these cases more aggressive surgical approaches and I-131 therapy, is paramount to achieving the best possible outcomes. DM on presentation in DTC are uncommon, with an incidence of 1-9%. However, the incidence of DTC is rising and the disease affects a relatively young cohort of patients. The aims of this study were to investigate predictive factors in the development of DM by comparing a homogenous group of DTC patients with and without DM, and to illustrate the overall and disease-specific survival (DSS) rates of DTC patients presenting with DM.

METHODS

A matched case-control study of patients with DTC and DM was undertaken. The study group comprised a consecutive series of cases with DM treated in the period 1968-2014. Patients with DM at initial presentation were identified (DTC-DM group). A control group of patients without DM were matched based on age, gender, tumour size and histological subtype. The primary outcome measures were overall and disease-free survival. Secondary outcome measures were lymph node involvement (LNI), extra-thyroidal extension (ETE) of tumour and presence of BRAFV600E mutation identified on immunohistochemistry.

RESULTS

A total of 2547 patients with DTC were reviewed and of these 83 (3.26%) had DM at initial presentation. At 5 and 10 years, the overall survival rates for DTC-DM patients were 89.6% and 64%, respectively. The 5 and 10 year DSS rates for DTC-DM cases were 90.2% and 67.3%, respectively. When compared to the DTC group, the DTC-DM group had significantly higher rates of ETE (63% vs. 29.5%, P < 0.0001) and LNI (32.5% vs. 18.8%, P = 0.044). Among patients with papillary thyroid cancer (PTC), the presence of BRAFV600E mutation was significantly associated with DM (62.2% vs. 36.8%, P = 0.028).

CONCLUSION

ETE, LNI and BRAFV600E mutation in PTC are significant predictors for the development of distant metastatic disease.

Long non-coding RNA signatures as predictors of prognosis in thyroid cancer: a narrative review

Thyroid cancer (TC) is the most common endocrine malignancy, with high incidence rates in recent decades. Most TC cases have good prognoses, but a high risk of recurrence and metastases poses challenges, especially for patients with high-risk factors. Currently used prognostic markers for TC involve a combination of genetic factors and overexpressed proteins. Long non-coding RNAs (lncRNAs) regulate several integral biologic processes by playing key roles in the transcription of several downstream targets maintaining cellular behavior. Prior studies have revealed that lncRNAs promote tumor cell proliferation, invasion, metastasis, and angiogenesis, making them important targets for therapeutic intervention in cancer. While the exact molecular mechanisms underlying the role of lncRNAs in modulating TC progression and recurrence is still unclear, it is important to note that some lncRNAs are upregulated in certain cancers, while others are downregulated. In the present study, we review several key lncRNAs, their association with cancer progression, and the important roles they may play as tumor suppressors or tumor promoters in tumorigenesis. We discuss the potential mechanisms of lncRNA-mediated pathogenesis that can be targeted for the treatment of TC, the existing and potential benefits of using lncRNAs as diagnostic and prognostic measures for cancer detection, and tumor burden in patients.

The Antitumour Effect of Prunella vulgaris Extract on Thyroid Cancer Cells In Vitro and In Vivo

Prunella vulgaris, a traditional Chinese medicine, has been used to treat various benign and malignant tumours for centuries in China. In our previous studies, Prunella vulgaris extract (PVE) was shown to promote apoptosis in differentiated thyroid cancer (DTC) cells. However, whether other mechanisms are involved in the antitumour effect of PVE in thyroid cancer (TC) cells remains unclear. The present study aimed to investigate the antiproliferative and antimigratory effects of PVE on TC cell lines both in vitro and in vivo. First, the TPC-1 and SW579 human TC cell lines were screened by MTT assay for their high level of sensitivity to PVE. Then, the results of cell growth curve and colony formation assay and cell cycle analyses, wound healing, and migration assays demonstrated that PVE inhibited the proliferation and migration of TPC-1 and SW579 cells. Moreover, the antitumour effect of PVE was verified in a subcutaneous xenotransplanted tumour model. Next, MKI67, PCNA, CTNNB1, and CDH1 were screened by qRT-PCR for their significantly differential expression levels in xenograft tissue with and without PVE treatment, and expression of MKI67, PCNA, and CDH1 was verified by Western blot. Finally, an integrated bioinformatics analysis containing protein-protein interaction network, KEGG pathway, and GO analysis was conducted to explore more potential antitumour mechanisms of PVE. In summary, PVE could inhibit the proliferation and migration of TC cells both in vitro and in vivo, which may have been achieved by modulation of the expression of MKI67, PCNA, and CDH1. These data suggest that PVE has the potential to be developed into a new anticancer drug for the treatment of TC.

From biomarkers to therapeutic targets: the promise of PD-L1 in thyroid autoimmunity and cancer

The programmed cell death-1/programmed cell death ligand-1 (PD-1/PD-L1) immune checkpoint proteins hold promise as diagnostic, prognostic, and therapeutic targets for precision oncology. By restoring antitumor T cell surveillance, the high degree of effectiveness of the immune checkpoint inhibitors (ICIs) has revolutionized cancer treatment. However, the majority of patients (65-80 %) treated with ICIs experience significant side effects, called immune-related adverse events (irAEs), resulting in autoimmune damage to various organs. Therefore, broadening the clinical applicability of these treatments to all cancer types requires an improved understanding of the mechanisms linking cancer immune evasion and autoimmunity. The thyroid is the endocrine gland the most frequently involved in autoimmunity and cancer, the growing incidence of which is raising serious public health issues worldwide. In addition, the risk of developing thyroid cancer is increased in patients with autoimmune thyroid disease and thyroid dysfunction is one of the most common irAEs, especially with PD‑1/PD-L1 blockade. Therefore, we chose the thyroid as a model for the study of the link between autoimmunity, irAEs, and cancer. We provide an update into the current knowledge of the PD‑1/PD-L1 axis and discuss the growing interest of this axis in the diagnosis, prognosis, and management of thyroid diseases within the context of autoimmunity and cancer, while embracing personalized medicine.

The age threshold of the 8th edition AJCC classification is useful for indicating patients with aggressive papillary thyroid cancer in clinical practice

BACKGROUND

Papillary thyroid cancer (PTC) is unique among cancers in that patient age is a consideration in staging. One of the most important modifications in the 8th Edition of the American Joint Committee on Cancer (AJCC) classification is to increase the age cut off for risk stratification in PTC from 45 to 55 years. However, whether this cut off is useful in clinical practice remains controversial. In the present study, we assessed how well this new age threshold stratifies patients with aggressive PTC.

METHODS

We retrospectively analyzed the clinicopathological features and overall survival rate of patients with PTC admitted to and surgically treated at a single surgical center. The study protocol was divided into two series. In each series all patients (n = 523) were divided in 2 groups according to age cut off. In the first series (cut off 45) patients < 45 (n = 193) vs. ≥45 (n = 330) were compared, and in the second series (cut off 55) patients < 55 (n = 306) vs. ≥55 (n = 217) were compared.

RESULTS

The rate of the prevalence of locally advanced disease (pT3 and pT4) was significantly higher in the patients above 55 years old than in those below 55 years old (p = 0.013). No significant differences were found for this parameter in series with cut off point 45 years old. A significantly higher risk of locally advanced disease T3 + T4 (OR = 4.87) and presence of LNM (N1) (OR = 3.78) was observed in ≥45 years old group (p = 0.021 and p < 0.0001, respectively). More expressive results were found for the patients ≥55 years old group, where the risk of locally advanced disease (T3 + T4) was higher (OR = 5.21) and LNM presence was OR = 4.76 (p < 0.001 and p < 0.0001, respectively). None of the patients below 55 years old showed distant metastasis, but 19 patients above 55 years old showed M1 (p < 0.0001). In older patients group (≥55 years old) we observed deaths related thyroid cancer in 11 individuals.

CONCLUSIONS

The age cut off of 55 years old for risk stratification proposed by the 8th Edition of AJCC effectively stratifies PTC patients with a poor prognosis, indicating it is likely to be useful in clinical practice.

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).

Plant natural products with anti-thyroid cancer activity

Thyroid cancer is the most frequent endocrine malignancy, with more than 500,000 cases per year worldwide. Differentiated thyroid cancers are the most common forms with best prognosis, while poorly/undifferentiated ones are rare (2% of all thyroid cancer), aggressive, frequently metastasize and have a worse prognosis. For aggressive, metastatic and advanced thyroid cancer novel antitumor molecules are urgently needed and phytochemical products can be a rational and extensive source, since secondary plant metabolites can guarantee the necessary biochemical variability for therapeutic purpose. Among bioactive molecules that present biological activity on thyroid cancer, resveratrol, curcumin, isoflavones, glucosinolates are the most common and used in experimental model. Most of them have been studied both in vitro and in vivo on this cancer, but rarely in clinical trial. This review summarizes phytochemicals, phytotherapeutics and plant derived compounds used in thyroid cancer.

Resveratrol Inhibits the Tumorigenesis of Follicular Thyroid Cancer via ST6GAL2-Regulated Activation of the Hippo Signaling Pathway

Follicular thyroid carcinoma (FTC) is a common endocrine malignancy with highly aggressive features. In this study, next-generation sequencing technology was used to identify aberrant expression of sialyltransferase (ST) family members in FTC. Aberrant high expression of alpha-2,6-sialyltransferase 2 (ST6GAL2) was demonstrated to promote tumorigenesis of FTC in vitro and in vivo. Furthermore, ST6GAL2 promoted tumorigenesis by inactivating the Hippo signaling pathway. Resveratrol is a native compound extracted from Vitis species, and many studies have confirmed its protective cardiovascular and antineoplastic effects. Here we found that resveratrol can inhibit the tumorigenesis of FTC by suppressing the expression of ST6GAL2, further activating the Hippo pathway. In summary, this study revealed the role of the ST6GAL2-Hippo signaling pathway in FTC tumorigenesis and indicated that resveratrol, a commonly found antineoplastic compound, could inhibit tumorigenesis of FTC by regulating the abovementioned pathways.

Thyroid nodules: diagnostic evaluation based on thyroid cancer risk assessment

Thyroid nodules are extremely common and can be detected by sensitive imaging in more than 60% of the general population. They are often identified in patients without symptoms who are undergoing evaluation for other medical complaints. Indiscriminate evaluation of thyroid nodules with thyroid biopsy could cause a harmful epidemic of diagnoses of thyroid cancer, but inadequate selection of thyroid nodules for biopsy can lead to missed diagnoses of clinically relevant thyroid cancer. Recent clinical guidelines advocate a more conservative approach in the evaluation of thyroid nodules based on risk assessment for thyroid cancer, as determined by clinical and ultrasound features to guide the need for biopsy. Moreover, newer evidence suggests that for patients with indeterminate thyroid biopsy results, a combined assessment including the initial ultrasound risk stratification or other ancillary testing (molecular markers, second opinion on thyroid cytology) can further clarify the risk of thyroid cancer and the management strategies. This review summarizes the clinical importance of adequate evaluation of thyroid nodules, focuses on the clinical evidence for diagnostic tests that can clarify the risk of thyroid cancer, and highlights the importance of considering the patient's values and preferences when deciding on management strategies in the setting of uncertainty about the risk of thyroid cancer.

Integrated analysis identifies DUSP5 as a novel prognostic indicator for thyroid follicular carcinoma

BACKGROUND

Differentiated thyroid cancer involves thyroid follicular carcinoma (FTC) and papillary thyroid carcinoma (PTC). Patients with FTC have a worse prognosis than those with PTC for early metastasis through blood of FTC. However, the mechanism of poor prognosis of FTC is still unclear. Here, we aim to evaluate the role of DUSP5 in the prognostic evaluation of FTC.

METHOD

We searched the Gene Expression Omnibus (GEO) database for the differentially expressed genes (DEGs) between FTC and PTC, and then combined with survival analysis of cBioPortal database to locate the gene significantly related to prognosis. Tissue microarrays and clinical tissues were used to examine DUSP5 expression by immunohistochemical (IHC) staining between FTC and PTC tissues. In vitro experiment, proliferation, migration and invasion of FTC were observed after regulation of DUSP5 by transfection of siRNA and plasmids, respectively.

RESULTS

After searching the GEO database, 26 DEGs were found. DUSP5 was significantly associated with prognosis of FTC in combination with survival analysis. Data of IHC staining showed lower expression of DUSP5 in FTC compared to PTC tissues. Furthermore, overexpression of DUSP5 inhibited the proliferation, migration and invasion accompanied with low level of MMP9 and Vimentin and high level of E-cadherin. Nevertheless, inhibition of DUSP5 ameliorated above damaging effect on the proliferation, migration and invasion.

CONCLUSION

DUSP5 was differentially expressed in FTC and PTC tissues. Low level of DUSP5 in FTC participates in the high frequency of metastasis, and further contributes to poor prognosis of FTC. DUSP5 could be served as a novel therapeutic target for FTC.

Radioiodine-Refractory Thyroid Cancer: Molecular Basis of Redifferentiation Therapies, Management, and Novel Therapies

Recurrent, metastatic disease represents the most frequent cause of death for patients with thyroid cancer, and radioactive iodine (RAI) remains a mainstay of therapy for these patients. Unfortunately, many thyroid cancer patients have tumors that no longer trap iodine, and hence are refractory to RAI, heralding a poor prognosis. RAI-refractory (RAI-R) cancer cells result from the loss of thyroid differentiation features, such as iodide uptake and organification. This loss of differentiation features correlates with the degree of mitogen-activated protein kinase (MAPK) activation, which is higher in tumors with BRAF (B-Raf proto-oncogene) mutations than in those with RTK (receptor tyrosine kinase) or RAS (rat sarcoma) mutations. Hence, inhibition of the mitogen-activated protein kinase kinase-1 and -2 (MEK-1 and -2) downstream of RAF (rapidly accelerated fibrosarcoma) could sensitize RAI refractivity in thyroid cancer. However, a significant hurdle is the development of secondary tumor resistance (escape mechanisms) to these drugs through upregulation of tyrosine kinase receptors or another alternative signaling pathway. The sodium iodide symporter (NIS) is a plasma membrane glycoprotein, a member of solute carrier family 5A (SLC5A5), located on the basolateral surfaces of the thyroid follicular epithelial cells, which mediates active iodide transport into thyroid follicular cells. The mechanisms responsible for NIS loss of function in RAI-R thyroid cancer remains unclear. In a study of patients with recurrent thyroid cancer, expression levels of specific ribosomal machinery-namely PIGU (phosphatidylinositol glycan anchor biosynthesis class U), a subunit of the GPI (glycosylphosphatidylinositol transamidase complex-correlated with RAI avidity in radioiodine scanning, NIS levels, and biochemical response to RAI treatment. Here, we review the proposed mechanisms for RAI refractivity and the management of RAI-refractive metastatic, recurrent thyroid cancer. We also describe novel targeted systemic agents that are in use or under investigation for RAI-refractory disease, their mechanisms of action, and their adverse events.

The binary presence or absence of lymph node metastasis or extrathyroidal extension is not associated with survival in papillary thyroid cancers: Implications for staging systems

BACKGROUND

The characteristics of diagnosed papillary thyroid cancer (PTC) have changed over time with the increasing trend of early diagnosis, and the survival impact of conventional prognostic factors such as lymph node metastasis (LNM) and extrathyroidal extension (ETE) is controversial. We investigated PTC prognostic factors for overall survival (OS) and disease specific survival (DSS), focusing on LNM, ETE, and their implications for PTC staging systems.

METHODS

We assessed prognostic factors for OS and DSS in a nationwide sample of Korean PTC patients (N = 5192, median follow-up 121 months) using Cox regression. The binary presence or absence of LNM and ETE, as well as other measures of LNM and ETE, were examined for their survival impact. We also evaluated the relative performance of PTC staging systems before and after revising the staging criteria for LNM and ETE.

RESULTS

The binary presence of LNM or ETE was not a prognostic factor for OS or DSS, nor were other various measures of LNM. However, the extent of ETE as none, microscopic, or gross independently influenced survival (OS hazard ratio for gross vs. none: 3.28, 95% confidence interval (CI) 1.97-5.46; DSS hazard ratio for gross vs. none: 3.75, 95% CI 1.59-8.81). The performance of PTC staging systems improved when the extent of ETE and/or location of LNM were used as staging components.

CONCLUSION

The extent of ETE and/or location of LNM may be better survival indicators than their binary presence or absence, and we propose staging criteria revisions to pertinent staging systems to better reflect the contemporary PTC population.

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

CONTEXT

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

DESIGN

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

MAIN OUTCOME MEASURES

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

CONCLUSIONS

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

Long non-coding RNA H19 knockdown inhibits the cell viability and promotes apoptosis of thyroid cancer cells through regulating the PI3K/AKT pathway

Certain long non-coding (lnc)RNAs have been reported to serve important roles in the genesis and progression of thyroid cancer (TC). Recent studies have demonstrated that the expression of lncRNA H19 is upregulated in TC tissues; however, knowledge of the associated molecular mechanisms is limited. Therefore, the present study aimed to clarify the roles of H19 in TC. The mRNA expression of lncRNA H19 in TC tissues was determined using reverse transcription-quantitative polymerase chain reaction analysis, and the effects of H19 knockdown on cell viability and apoptosis in vitro were assessed using MTT and flow cytometric assays, respectively. Finally, the signaling pathways involved in the effects of H19 were examined. The results indicated that H19 was upregulated in TC tissues. Silencing of H19 inhibited the cell viability and promoted apoptosis of FTC-133 and TPC-1 TC cells, accompanied by an increased expression of B-cell lymphoma 2 (Bcl-2)-associated X protein and caspase 3, and repressed expression of Bcl-2. The results of western blot analysis suggested that the levels of phosphorylated phosphoinositide-3 kinase (PI3K) and phosphorylated AKT were attenuated by H19 silencing. These results suggest that lncRNA H19 exerts an oncogenic function in TC, in part through the PI3K/AKT pathway.

PROGRAMMED CELL DEATH-LIGAND 1 OVEREXPRESSION IN THYROID CANCER

OBJECTIVE

Programmed cell death-ligand 1 (PD-L1) expression on tumor tissue has been associated with favorable response to anti-programmed cell death-receptor 1/PD-L1 therapy in many human cancers. Studies have reported that PD-L1 is also expressed in thyroid cancer. The objective of this paper is to introduce the potential predictive and therapeutic values of PD-L1 in thyroid cancer.

METHODS

A literature search was conducted in the PubMed database using the terms "PD-L1," "B7-H1," and "thyroid cancer." PD-L1 positivity was determined by immunohistochemical assay.

RESULTS

The frequency of PD-L1 positivity in different studies ranged from 6.1 to 82.5% in papillary thyroid cancer (PTC) patients and 22.2 to 81.2% in anaplastic thyroid cancer (ATC) patients. PD-L1 positivity rate was higher in ATC than in PTC within the same studies, and its expression intensity was significantly higher in tumor tissue than in the corresponding nontumor thyroid tissues. Moreover, PD-L1 expression was positively associated with the aggressiveness and recurrence of thyroid cancers and negatively associated with the differentiation status and outcomes. PD-L1 checkpoint pathway blockade may emerge as a promising therapeutic target in the treatment of thyroid cancers.

CONCLUSION

PD-L1 is a potential biomarker to predict the recurrence and prognosis of thyroid cancers. It is also a novel immunotherapy target for optimizing the management landscape of radioiodine-refractory and ATCs.

ABBREVIATIONS

ATC = anaplastic thyroid cancer; DTC = differentiated thyroid cancer; IHC = immunohistochemical; OS = overall survival; PD-1 = programmed cell death-receptor 1; PD-L1 = programmed cell death-ligand 1; PD-L2 = programmed cell death-ligand 2; PTC = papillary thyroid cancer; TNM = tumor-node-metastasis; Treg = regulatory T cell.

Papillary Thyroid Micro Carcinoma: The Incidence of High-Risk Features and Its Prognostic Implications

Background: The current management of papillary thyroid micro carcinoma (PTMC) has become more conservative. However, high-risk characteristics that can only be revealed post-surgically exist. Patients and clinicians need to estimate the risks and understand the prognostic meaning of these factors. Methods: We retrospectively analyzed 246 consecutive patients with PTMC who underwent surgery at our institution between 2015 and 2017. Clinical and histopathological parameters that may indicate recurrent disease were investigated. The responses to therapy in cases with different risks of recurrence were analyzed. Results: A total of 79.26% (195/246) of patients received total thyroidectomy (TT), of whom 177 (90.77%) also received central lymph node dissection. Radioiodine ablation (RAI) was applied in 64.23% (158/246) of patients. Intermediate-high risk features were identified in 27.64% (68/246) after primary treatment. After a median follow-up of 18 months (range, 6-39 months), 121 of 158 (76.58%) patients who received TT+RAI were evaluated as an excellent response. An incomplete response (IR) was observed in 14.56% (23/158) of this group of PTMC. Multivariate analysis identified extra thyroid extension (P = 0.001) and intermediate-high risk stratification (P = 0.014) as significant and independent risk factors for an IR. Conclusions: A total of 27.64% of PTMC cases evaluated as a low risk of recurrence pre-surgery showed intermediate to high risk disease post-surgery, and this leads to a higher rate of IR.

MiR-19a Overexpression in FTC-133 Cell Line Induces a More De-Differentiated and Aggressive Phenotype

In recent years, microRNAs (miRNAs) have received increasing attention for their important role in tumor initiation and progression. MiRNAs are a class of endogenous small non-coding RNAs that negatively regulate the expression of several oncogenes or tumor suppressor genes. MiR-19a, a component of the oncogenic miR-17-92 cluster, has been reported to be highly expressed only in anaplastic thyroid cancer, the most undifferentiated, aggressive and lethal form of thyroid neoplasia. In this work, we evaluated the putative contribution of miR-19a in de-differentiation and aggressiveness of thyroid tumors. To this aim, we induced miR-19a expression in the well-differentiated follicular thyroid cancer cell line and evaluated proliferation, apoptosis and gene expression profile of cancer cells. Our results showed that miR-19a overexpression stimulates cell proliferation and alters the expression profile of genes related to thyroid cell differentiation and aggressiveness. These findings not only suggest that miR-19a has a possible involvement in de-differentiation and malignancy, but also that it could represent an important prognostic indicator and a good therapeutic target for the most aggressive thyroid cancer.

The efficacy of radioactive iodine for the treatment of well-differentiated thyroid cancer with distant metastasis

Objective

Radioactive iodine (¹³¹I) has been used as a treatment for high-risk well-differentiated thyroid cancer after thyroidectomy. The aim of this study was to evaluate the long-term follow-up results after using high accumulated doses of ¹³¹I (>600 mCi) for the treatment of well-differentiated thyroid cancer.

Patients and methods

In this study, we retrospectively evaluated prospectively enrolled patients with well-differentiated thyroid cancer who were treated and followed up in Chang Gung Memorial Hospital in Linkou and Keelung, Taiwan. All the patients underwent thyroidectomy between 1979 and 2016.

Results

For our study, 228 patients with papillary and follicular thyroid carcinoma with distant metastases were enrolled. Of the 228 patients, 71 (31.1%) received ¹³¹I therapy with an accumulated dose of at least 600 mCi. Forty-four died because of disease-specific mortality (DSM) after a mean follow-up of 10.6±6.3 years. Compared with the patients in the DSM group, which included 27 survival cases, patients who were younger, and those with a multifocal tumor, more extensive thyroidectomy, and papillary thyroid carcinoma showed better prognosis. The DSM group included a higher percentage of patients who developed a secondary primary cancer after receiving a diagnosis of thyroid cancer than the survival group (18.2 vs. 3.7%). However, the difference did not reach statistical significance (P=0.075).

Conclusion

¹³¹I provided an effective therapeutic modality for well-differentiated thyroid cancer patients with distant metastasis. After a mean of follow-up 10 years, more than 60% of cases resulted in DSM when high accumulated ¹³¹I doses were administered.

Routine thyroglobulin, neck ultrasound and physical examination in the routine follow up of patients with differentiated thyroid cancer-Where is the evidence?

PURPOSE

Patients with differentiated thyroid cancer (DTC) typically have a favourable prognosis and recurrence as late as 45 years after diagnosis has been reported. International clinical guidelines for monitoring recommend routine thyroglobulin, ultrasound and physical examination for the detection of recurrence. The aim of this review was to systematically review whether routine monitoring using thyroglobulin (Tg), neck ultrasound and physical examination for recurrence in differentiated thyroid cancer patients is effective in improving patient survival and/or quality of life.

METHODS

Primary studies were retrieved via a comprehensive search of three electronic bibliographic databases (PubMed, Web of Science Core Collection and Cochrane Library) without time restriction. Eligible studies must have reported on disease-free patients with DTC subject to long-term routine surveillance. The primary and secondary outcomes of interest were overall survival (or other survival parameters) and quality of life, respectively.

RESULTS

Literature searches yielded 5529 citations, which were screened by two reviewers. 241 full texts were retrieved. No randomised controlled trials or two-arm cohort studies on the effectiveness of any of the three specified interventions were identified. However, three 'single-arm' studies reporting long-term follow-up outcomes in patients undergoing regular surveillance were identified and appraised.

CONCLUSIONS

This review highlights a lack of empirical evidence to support current use of routine surveillance in DTC. Although early detection is possible, routine surveillance may lead to unnecessary intervention.

Standards and Definitions in Neck Dissections of Differentiated Thyroid Cancer

Papillary and follicular thyroid carcinomas arising from the follicular epithelial cells and forming differentiated thyroid cancer (DTC) consist of >95% of thyroid cancers. Lymph node metastasis to the neck is common in DTC, especially in papillary thyroid cancer. The removal of only the metastatic lymph nodes (berry picking) does not help to achieve a potential positive contribution to the survival and recurrence of lymph node dissection in the DTC. Thus, systematic dissection of the cervical lymph nodes is needed. Today, according to the widely accepted and commonly used definitions and lymph node staging, the deep lymph nodes of the lateral side of the neck are divided into five regions. Based on the fact that some groups have biologically independent regions, Groups I, II, and V are divided into the A and B subgroups. The central region lymph nodes contain VI and VII region lymph nodes, which consist of the prelaryngeal, pretracheal, and right and left paratracheal lymph node groups. Radical neck dissection (RND) is accepted as the standard basic procedure in defining neck dissections. In this method, in addition to all the regions of the Groups I-V lymph nodes at one side, the ipsilateral spinal accessory nerve, internal jugular vein, and sternocleidomastoid muscle are removed. Sparing of one or more of the routinely removed non-lymphatic structures in the RND is called modified RND (MRND), whereas the preservation of one or more of the routinely removed lymph node groups in the RND is termed as selective neck dissection (SND). In difference, the procedure with an addition of a lymph node and/or non-lymphatic structures to routinely removed neck structures in RND is called extended RND. Generally, involving one or more regions of SND are applied for DTC. The removal of the paratracheal, prelaryngeal, and pretracheal lymph node groups at one side is termed as ipsilateral central dissection, whereas the removal of the bilateral paratracheal lymph node groups, in other words, the excision of four lymph node groups in the central region (Groups VI and VII), is defined as bilateral central dissection. In conclusion, bilateral central neck dissection (CND) is the SND in which the regions of VI and VII are removed. In the DTC, CND is prophylactically and therapeutically applied, whereas lateral neck dissection is performed only therapeutically in the presence of clinical metastasis (N1b) in the lateral neck region. Debates on the extent of SNDs to be made in the central and lateral neck regions are still ongoing. Central dissection should be made at least unilaterally. In the lateral side of the neck, SNDs can be applied in different combinations in which at least one region from Groups I to V is removed. The main variables that determine the extent of SND in the central and lateral regions in DTC are the complication rates, the effect of the procedure, and its effect on prognosis and recurrence.

Whole-Exome Sequencing Identifies Two Discrete Druggable Signaling Pathways in Follicular Thyroid Cancer

BACKGROUND

Thyroid cancer is the most common endocrine malignancy, with continuously increasing incidence. Follicular thyroid cancer (FTC) accounts for approximately 10% to 15% of these cases and is known to be associated with several gene mutations. The purpose of this study was to identify novel therapeutic targets in FTC using whole-exome sequencing (WES) and bioinformatics analysis.

STUDY DESIGN

Whole-exome sequencing was performed on 6 established FTC cell lines. Stringent false-proof filtering and exclusion of synonymous and known polymorphisms yielded novel missense, nonsense, and splice-site single nucleotide variants (SNV). Gene variants were analyzed for structural, functional, and evolutionary properties using GO (Gene Ontology), Pfam (Protein Families), and KEGG (Kyoto Encyclopedia of Genes and Genomes) searches by STRING (Search Tool for the Retrieval of Interacting Genes/Proteins) and GORILLA (Gene Ontology enRIchment anaLysis and visuaLizAtion tool) analyses. A false discovery rate of <0.5 was used to denote significantly enriched signaling pathways.

RESULTS

An average of 657 (range 366 to 1,158) SNVs including 31 (range 12 to 53) known cancer driver genes were identified in FTC cell line exomes. The SNV burden, distribution, frequency, and signature followed the known thyroid mutation profiles, without chromosomal bias. Recurrently mutated cancer driver genes included FRG1 (6/6), CDC27, NCOR1, PRSS1 (5/6), AHCTF1, MUC20, PABPC1, and PABPC3 (4/6). Pathway analysis using bioinformatics tools STRING and GORILLA segregated FTC cell lines into 2 druggable signaling groups showing dominant RAS/ERK1-2/AKT and CDK1/CyclinB signaling pathway targets.

CONCLUSIONS

Next-generation sequencing tools can be used to identify druggable signaling targets for precision treatment of FTCs.