Thyroid Incidentalomas: Scrutinizing the Mode of Detection and Evaluating its Contribution to Thyroid Cancer Diagnosis

There is an ongoing debate about the reasons behind the increasing incidence of thyroid cancer in the last two to three decades. Here, we investigate how thyroid nodules were detected in a large series of consultations for thyroid nodular pathology.

METHODS

In total, 576 patients were analyzed, with a total of 1014 nodules described.

RESULTS

In 347 (60.2%) cases, the diagnosis of a thyroid nodule was incidental, mostly during imaging tests for other reasons. Incidental diagnosis occurred among all ranges of nodule diameter and between palpable and non-palpable cases, even within a small proportion of symptomatic cases. In univariate analysis, incidental diagnosis was associated with smaller nodule diameter, non-palpable nodules, asymptomatic cases, older patient age, less advanced stages (T1-2), and conservative management. After multivariate analysis, older age, euthyroidism, and smaller diameter were statistically significant. Incidental diagnosis contributed to the diagnosis of 53.8% of the cases of cancer. Advanced T stages (T3-4) were more common in non-incidental diagnoses.

CONCLUSION

Our results indicate that incidental diagnosis of thyroid nodules is a significant contributor to thyroid cancer diagnosis in all ranges of nodule diameter, especially at earlier stages.

Genotype-Phenotype Correlations in Thirty Japanese Patients with Congenital Hypothyroidism Attributable to TG Defects

CONTEXT

Thyroglobulin (Tg), encoded by TG, is essential for thyroid hormone synthesis. TG defects result in congenital hypothyroidism (CH). Most reported patients were born before the introduction of newborn screening (NBS).

OBJECTIVE

We aimed to clarify the phenotypic features of patients with TG defects diagnosed and treated since the neonatal period.

SUBJECTS AND METHODS

We screened 1061 patients with CH for thirteen CH-related genes and identified thirty patients with TG defects. One patient was diagnosed due to hypothyroidism-related symptoms and the rest were diagnosed via NBS. Patients were divided into two groups according to their genotypes, and clinical characteristics were compared. We evaluated the functionality of the seven missense variants using HEK293 cells.

RESULTS

Twenty-seven rare TG variants were detected, including fifteen nonsense, three frameshift, two splice-site, and seven missense variants. Patients were divided into two groups: thirteen patients with biallelic truncating variants and seventeen patients with monoallelic/biallelic missense variants. Patients with missense variants were more likely to develop thyroid enlargement with TSH stimulation than patients with biallelic truncating variants. Patients with biallelic truncating variants invariably required full hormone replacement, whereas patients with missense variants required variable doses of levothyroxine. Loss of function of the seven missense variants was confirmed in vitro.

CONCLUSION

To our knowledge, this is the largest investigation on the clinical presentation of TG defects diagnosed in the neonatal period. Patients with missense variants showed relatively mild hypothyroidism with compensative goiter. Patients with only truncating variants showed minimal or no compensative goiter and required full hormone replacement.

Prophylactic effect of pilocarpine on acute sialadenitis following radioactive iodine therapy in thyroid cancer patients

Purpose: Our aim was to evaluate the effect of prophylactic pilocarpine on acute salivary symptoms after radioactive iodine (RAI) therapy in patients with differentiated thyroid cancer. Methods: We enrolled 88 patients (76 women and 12 men; mean age: 47 years; range: 20-74 years) with differentiated thyroid cancer who received RAI. Patients were divided into pilocarpine (51 patients) and control (37 patients) groups. Pilocarpine was given orally, at a dose of 5 mg three times a day, from 2 days before and 12 days after RAI therapy. Symptoms and signs of acute sialadenitis within 3 months of RAI therapy were recorded. Results: During the 3 months after RAI therapy, 13 of the 88 patients (14.7%) developed acute symptomatic sialadenitis (swelling or pain of salivary glands). Acute salivary symptoms were reported by 4 (7.8%) and 9 (24.3%) patients in the pilocarpine and control groups, respectively. Acute salivary symptoms were less frequent in the pilocarpine than control group (p = 0.04), but did not differ by age, sex, or RAI dose (p = 0.3357, p = 0.428, and p = 0.2792). Conclusions: Pilocarpine reduced the likelihood of acute sialadenitis after RAI therapy in patients with differentiated thyroid cancer.

Increased Screening Rates for Thyroid Cancer Among Residents Living Near Nuclear Power Plants

Frequent screening for thyroid cancer has been suggested as a probable explanation for the observed high risk of thyroid cancer in nuclear power plant (NPP) areas. We aimed to compare thyroid cancer screening rates of residents living near NPPs to those of the general population. This study utilized data from two national survey-based studies in 2016 and in 2014, respectively, for residents (n = 1,200) living in administrative districts within 5 km of NPP sites as the interest group, and the general population (n = 228,712) including distant-living residents (n = 19,100) in administrative districts within 30 km of NPP sites as reference groups. We observed an increase in screening rates in residents near NPPs, which may lead to a higher possibility of thyroid cancer detection. Therefore, further epidemiological studies investigating radiation-induced thyroid cancer risk among residents near NPPs should be carefully designed and interpreted considering possible detection bias.

Survival rate of thyroid cancer in the Asian countries: a systematic review and meta-analysis study

PURPOSE

Overall, thyroid cancer is the most common endocrine malignancy. This cancer is fifth most common cancer among adult women and the second most common cancer in women over 50 years old and it occurs in women 3 times more than men. The present systematic review and meta-analysis were designed with the aim of determining the 5-year survival rate of thyroid cancer in Asian countries in 2022.

METHODS

The current study is a systematic review and meta-analysis of thyroid cancer survival rates in Asian countries. Researchers in the study searched for articles published in six international databases: PubMed/Medline, EMBASE, Scopus, Google Scholar, ISI (Web of Knowledge), and ProQuest until July 03, 2022. A checklist (The Newcastle-Ottawa Quality Assessment Form) has been prepared in previous studies to evaluate the quality of articles.

RESULTS

In general, 38 articles were entered for the meta-analysis. The 5-year survival rate was 95.3%, with a 95% confidence interval of 93.5% to 96.6%. The year of study is a cause of variability in results of 5-year (Reg Coef = 0.145, P < 0.001). According to the results, an increased survival rate across the study period was observed. Human Development Index was a cause of variability in results of 5-year survival rates (Reg Coef = 12.420, P < 0.001). The results of Table 2 showed that women have 4% more 5-year survival rate than men (Hazard ratio: 1.05 CI: 95% 1.04-1.06)).

CONCLUSION

In general, the 5-year survival of thyroid cancer in Asian countries was higher than in European countries, but it is at a lower level than in the United States.

Update regarding the role of PD-L1 in oncocytic thyroid lesions on cytological samples

AIMS

Several papers have shown that programmed death-ligand 1 (PD-L1) expression is a relevant predictive biomarker in anti-PD-L1 cancer immunotherapy. While its role in several human cancers is correlated with poor prognosis and resistance to anticancer therapies, in thyroid cancers the role of PD-L1 remains questionable. Few articles have studied PD-L1 in thyroid fine-needle aspiration cytology (FNAC), demonstrating a possible correlation with papillary thyroid carcinoma. However, its role in oncocytic thyroid lesions remains controversial. We accordingly examine the performance of PD-L1 immunostaining in liquid based cytology (LBC) from oncocytic lesions.

METHODS

From January 2019 to March 2021, 114 thyroid lesions diagnosed by FNAC from lesions with a predominant oncocytic component, were enrolled for evaluation by PD-L1 immunostaining on both LBC and corresponding histology samples.

RESULTS

The FNAC cohort included 51 benign (B, negative controls), 4 atypia of undetermined significance/follicular lesions of undetermined significance (AUS/FLUS), 57 follicular lesions (follicular neoplasm/suspicious for FN, FN/SFN) and 2 suspicious for malignancy (SFM) cases. Fifty-four cases (11B, 2 AUS/FLUS, 39 FN/SFN and 2 SFM) had histological follow-up including: 1B case resulted as a hyperplastic oxyphilic nodule in Hashimoto thyroiditis (HT), 10B as goitre, 2 AUS/FLUS cases as oncocytic adenomas (OAs); 39 FN/SFN included 27 OAs, 4 FA and 8 oncocytic follicular carcinoma (OFC). The two SFM cases were diagnosed on histopathology as OAs. Increased plasma membrane and cytoplasmic PD-L1 expression were found in 47 cases of the LBC cases (41.2%). Among the histological series, 67.3% of OAs and 75% of OFC had PD-L1 expression, while negative PD-L1 was found in hyperplastic oncocytic cells in HT. A positivity in more than 30% of the neoplastic cells was found in 72.9% of the cases including six OFC.

CONCLUSIONS

These data suggest that PD-L1 expression is expressed in oncocytic thyroid lesions. While weak PD-L1 expression failed to discriminate benign from malignant lesions, OFC demonstrated more intense cytoplasmic and membranous expression.

Analysis of 665 thyroid nodules using both EU-TIRADS and ACR TI-RADS classification systems

BACKGROUND

Ultrasound-based classification systems allow stratification of thyroid nodules to recommend fine-needle aspiration (FNA) based on their malignancy risk. However, these have discrepancies that may have an impact in thyroid cancer detection. We aimed to compare European Thyroid Association (EU-TIRADS) and American College of Radiology (ACR TI-RADS), in terms of FNA indication and diagnostic performance.

METHODS

Retrospective study of 665 thyroid nodules from 598 patients who underwent ultrasound and fine-needle aspiration at a tertiary-care institution between January 1st of 2016 and July 31st of 2019. Based on their sonographic features they were classified according to the EU-TIRADS and ACR TI-RADS classification and then their cytological results were obtained. Differences in FNA indications according to these two classifications were analysed. In patients who underwent surgical removal of the nodules, the final pathological diagnosis was obtained.

RESULTS

A statistically significant association was found between EU-TIRADS and ACR TI-RADS classification systems (p < 0.001). ACR TI-RADS allowed greatest reduction in FNA performed (32% vs 24.5%). A different risk category was obtained in 174 (26.1%) nodules, mostly higher with EU-TIRADS. The indication to FNA changed in 54 (8.1%) nodules (49 only indicated following EU-TIRADS recommendations), of which 4 had Bethesda IV and 5 had Bethesda III cytology. The FNA indication in a higher number of nodules using EU-TIRADS was due to difference in the dimensional threshold for FNA on low-risk nodules; to the fact that hypoechogenicity in a mixed nodule ascribes it moderate risk, while using ACR TI-RADS it would only be considered of low risk, and to the use of isolated sonographic features, namely marked hypoechogenicity, microcalcifications and irregular margins, to automatically categorize a nodules as high risk in EU-TIRADS, while ACR TI-RADS requires a group of potentially suspicious features to consider a nodule of high risk. The analysis of pathology proven nodules revealed equally good sensitivity of both systems in the detection of malignancy, but weak specificity, slightly greater with ACR TI-RADS (27.1% vs 18.6%).

CONCLUSIONS

The EU-TIRADS and ACR TI-RADS are both suitable to assess thyroid nodules and through risk stratification avoid unnecessary FNA. FNA was less performed using ACR TI-RADS, which was slightly more efficiency in excluding malignancy.

A systematic-review of endotracheal stenting in patients with locally advanced thyroid cancer

OBJECTIVE

Locally aggressive thyroid cancer can result in airway obstruction secondary to tracheal compression or vocal cord palsy. A tracheal stent provides an alternative to surgical resection, tracheostomy or conservative management in patients with compressive symptoms. This systematic review synthesises the current evidence associated with tracheal stenting in locally advanced thyroid cancer.

DESIGN, SETTING AND PARTICIPANTS

We conducted a systematic review of tracheal stenting in locally advanced thyroid cancers. We searched MEDLINE, Embase and Web of Science for studies until September 22nd 2020. Inclusion criteria were studies involving patients who had received tracheal stents to treat laryngo-tracheal stenosis secondary to locally advanced thyroid cancer. Single case reports or single cases were not included.

MAIN OUTCOME MEASURES

We assessed studies for data on the performance of tracheal stenting; defined as symptomatic relief, spirometry data, complication rates and mortality. We also extracted data pertaining to the use of different types of stent.

RESULTS

We identified 8 full-text articles from 325 titles found in our search. These were all single-centre retrospective studies that lacked homogeneity of thyroid cancer histotypes. The number of patients in each study ranged from 4 to 35 patients. Stenting improved performance status (2 of 2 studies), symptoms (5 of 5 studies) and spirometry (2 of 3 studies). The most common complications were tracheal granulation, tumor overgrowth, stent migration and sputum retention.

CONCLUSION

There is a lack of evidence in the literature of tracheal stents in locally advanced Thyroid cancer. However, the evidence available suggests tracheal stenting may be a useful treatment adjunct in advanced thyroid cancer causing symptomatic airway obstruction.

Analysis of anteroposterior-to-transverse ratio in predicting thyroid malignancy on ultrasonography

OBJECTIVE

To explore the diagnostic value of anteroposterior-to-transverse ratio for predicting thyroid cancer.

METHODS

A total of 2306 nodules were divided into 5 groups according to their size. The ability of the anteroposterior-to-transverse ratio to predict thyroid cancer was analysed in each group on the basis of the sensitivity, specificity, accuracy and Youden index.

RESULTS

The median anteroposterior-to-transverse ratio was 0.83, with an interquartile range of 0.28. The area under the receiver operating characteristic curve was 0.709 (p < 0.001). When the diameter of a thyroid nodule was less than 1.5 cm, an anteroposterior-to-transverse ratio of more than 0.9 was associated with higher sensitivity, accuracy and Youden index, compared with an anteroposterior-to-transverse ratio of greater than 1.0, but the specificity was lower. When the diameter of a thyroid nodule was 1.5 cm or more, an anteroposterior-to-transverse ratio of greater than 0.9 was associated with higher sensitivity and Youden index, compared with an anteroposterior-to-transverse ratio of greater than 1.0, but specificity and accuracy were lower.

CONCLUSION

The anteroposterior-to-transverse ratio was a meaningful indicator of thyroid cancer, and its predictive effectiveness could be influenced by nodule size.

[Primary Health Care Follow-up of Patients with Differentiated Thyroid Cancer: Are We Ready?]

N/a.

Isthmusectomy for well-differentiated thyroid carcinoma located to the isthmus: A report of two cases and review of the literature

Papillary thyroid cancer is the most common endocrine malignancy, and due to its favorable prognosis, the extent of surgery has been a matter of debate. About 10% of these tumors are located in the thyroid isthmus, with no specific management in current guidelines. In the last decades, isthmusectomy has been proposed as a therapeutic option for isthmic papillary thyroid carcinoma, although there is no consensus on its management. We present two cases of patients from our institution with solitary isthmic papillary thyroid carcinoma without clinical macroscopic extrathyroidal extension or clinical-radiological lymph node involvement who were treated with isthmusectomy without prophylactic lymph node dissection. Neither of them had any postoperative complications. Both had an intermediate risk of recurrence due to aggressive variants. None of them had signs of recurrence during follow-up. We intend to show that isthmusectomy seems to be an effective and safe surgical alternative in selected patients through these cases.

Canadian consensus statement on the management of radioactive iodine-resistant differentiated thyroid cancer

Radioactive iodine-resistant differentiated thyroid cancer (RAIRTC) is an aggressive form of thyroid cancer that is uncommon and heterogeneous in its clinical behavior. With the emergence of more effective systemic therapy, the need for guidance in decision-making was recognized and a consensus committee of national experts was assembled. The consensus committee consisted of 13 clinicians involved in treating RAIRTC from across Canada and included endocrinologists, nuclear medicine physicians, surgeons, and radiation and medical oncologists. Domains of interest were identified by consensus, and evidence gathered using systematic reviews. Consensus recommendations for the diagnosis and management of RAIRTC were developed. It was recognized that the rarity of RAIRTC in practice and heterogeneous patterns of thyroid cancer care could limit access to effective therapy for some RAIRTC patients. This document offers guidance to manage RAIRTC patients in a multidisciplinary manner.

Metastatic Dedifferentiated Chondrosarcoma to Thyroid Gland: A Case Report

A 54-year-old man presented with a pathologic hip fracture secondary to a right femur tumor. A reaming biopsy showed the diagnosis of dedifferentiated chondrosarcoma (DDC). In addition, the patient had a thyroid mass. Fine needle aspirate from the thyroid mass revealed numerous large fragments of cohesive spindle cells with moderate nuclear atypia and brisk mitosis, identical to the femur tumor. Immunohistochemical staining on cell blocks of thyroid aspirate showed positivity for mesenchymal markers and negativity for epithelial and thyroid markers. The metastasis of DDC to the thyroid gland is a very rare incident and has previously been described once in the literature. In this report, we describe the clinical and pathologic findings of this case.

Application of thermography in the diagnostic investigation of thyroid nodules

Thyroid nodules (TN) are common in the general population, and the clinical importance of diagnosing thyroid nodules is based on excluding the possibility of thyroid cancer, which occurs in 7-15% of cases. The thyroid gland, owing to its superficial location, is easily accessible via thermography, a noninvasive method of recording body temperature that measures infrared radiation emitted by the body surface. Therefore, this study aimed to evaluate the temperature differences between benign and malignant TN by using thermography. We conducted a cross-sectional study where 147 TN were divided into two groups: the first group included 120 benign nodules and the other included 27 malignant nodules. All the nodules were subjected to ultrasound, fine needle aspiration biopsy, and thermography. On analyzing the thermography results, the benign nodules had a higher temperature at the beginning of the thermography evaluation, and the malignant nodules showed a higher temperature in the middle and at the end (Ft). Using the relationships, it was observed that the temperature delta (ΔT), ΔT nodule/ΔT healthy, ΔT nodule minus ΔT healthy, and nodule Ft minus Ft of the healthy region were higher in malignant nodules. The ROC curve analysis of ΔT demonstrated a cutoff point of 2.38°C, with a sensitivity of 0.963 and specificity of 0.992. Malignant nodules have higher temperatures than benign nodules on thermographic evaluation. This finding suggests that thermography can be a useful tool in the diagnosis of thyroid nodules.

Disease-free Survival of Patients with Differentiated Thyroid Cancer: A Study from a Tertiary Center in Oman

Objectives

As with global trends, the prevalence of differentiated thyroid cancer (DTC) has increased in recent years in Oman. However, to the best of our knowledge, no local studies have yet been published evaluating the prognosis of DTC cases in Oman. This study aimed to assess disease-free survival (DFS) and prognostic factors related to DTC among Omani patients attending a tertiary care center.

Methods

This retrospective, observational cohort study was conducted between January 2006 and May 2016 at the National Diabetes and Endocrine Center in Oman. Data related to DFS and prognostic factors were obtained from the electronic medical records of all ≥ 18-year-old patients diagnosed with DTC during the study period.

Results

A total of 346 DTC cases were identified. Overall, 82.7% of patients were disease-free at their last follow-up appointment. Univariate analysis indicated that various tumor characteristics including histological subtype (i.e., papillary carcinoma, Hurthle cell cancer, and minimally invasive follicular thyroid carcinoma), lymph node status, number of lymph node metastases, distant metastasis status, and TNM status (primary tumor (T), regional lymph node (N), distant metastasis (M) stage) were strong prognostic factors for DFS (p < 0.050). According to multivariate regression analysis, lymph node status, extrathyroidal extension, and angiovascular invasion were independent predictors of DFS (p < 0.050).

Conclusions

The overall prognosis of DTC among Omani patients was excellent. Treatment and follow-up strategies for patients with DTC should be tailored based on the individual’s risk factor profile.

Relevance of level IIb neck dissection in patients with papillary thyroid carcinoma

BACKGROUND

Cervical nodal metastasis is a key prognostic factor in patients with papillary thyroid carcinoma. The role of lymph nodes in papillary thyroid carcinoma management and prognosis remains controversial.

METHODS

Level IIb lymph nodes obtained from 44 patients with papillary thyroid carcinoma were histopathologically examined retrospectively. Specimens were classified as ipsilateral or contralateral. The number of dissected nodes and prevalence of level IIb metastasis were compared according to pre-operative clinical nodal stage.

RESULTS

In the node-negative neck, the prevalence of contralateral and ipsilateral IIb nodes was 0 out of 20 and 0 out of 3, respectively. In the node-positive neck, the prevalence of contralateral and ipsilateral IIb nodes was 1 out of 13 (7.70 per cent) and 3 out of 41 (7.32 per cent), respectively. Clinically determined and pathologically confirmed level IIb node negativity were significantly associated. Thirty-four patients (77.3 per cent) developed accessory nerve complications from level IIb dissection.

CONCLUSION

Level IIb neck dissection for papillary thyroid carcinoma may be required if pre-operative examination reveals multilevel, level IIa or suspicious level IIb metastasis.

Initial Experience With Robotic Modified Radical Neck Dissection Using the da Vinci Xi System Through the Bilateral Axillo-Breast Approach

Objectives.

The bilateral axillo-breast approach (BABA) to robotic thyroidectomy has been extended to modified radical neck dissection (MRND). This study assessed outcomes in patients who underwent robotic MRND through BABA using the da Vinci Xi system.

Methods.

The medical records of 40 patients who underwent total thyroidectomy, bilateral central neck dissection, and MRND from September 2018 to March 2020 were reviewed retrospectively, including 12 who underwent robotic surgery and 28 who underwent open surgery. All operations were performed by a single endocrine surgeon.

Results.

The operation time was significantly longer in the robotic group than in the open group (277.08±32.64 vs. 191.43± 60.43 minutes, respectively, P<0.01), but the number of retrieved lymph nodes did not differ significantly (32.58± 9.31 vs. 34.54±10.90, respectively, P=0.569). The incidence of transient hypoparathyroidism was significantly lower in the robotic group (16.7% [2/12] vs. 53.6% [15/28], P=0.041). The mean hospital stay was shorter (3.92±0.90 vs. 4.71±1.63 days) and the pain score on the first postoperative day was lower (2.92±0.29 vs. 3.18±0.67) in the robotic group. Six of the 12 patients (50%) in the robotic group had stimulated thyroglobulin levels <1.0 ng/mL.

Conclusion.

Robotic MRND through BABA has several advantages, including excellent cosmetic outcomes and a lower incidence of transient hypoparathyroidism than is the case for open MRND. Robotic MRND through BABA may be a promising surgical approach compared with conventional open MRND.

North East London coronavirus disease 2019 protocol for diagnostics in two-week wait head and neck cancer patients

Background

The coronavirus disease 2019 pandemic requires urgent modification to existing head and neck cancer diagnosis and management practices. A protocol was established that utilises risk stratification, early investigation prior to clinical review and a reduction in aerosol generating procedures to lessen the risk of coronavirus disease 2019 spread.

Methods

Two-week wait referrals were stratified into low, intermediate and high risk. Low risk patients were referred back to primary care with advice; intermediate and high risk patients underwent investigation. Clinical encounters and aerosol generating procedures were minimised. A combined diagnostic and therapeutic surgical approach was undertaken where possible.

Results

Forty-one patients were used to assess feasibility. Thirty-one per cent were low risk, 35 per cent were intermediate and 33 per cent were high risk. Thirty-three per cent were discharged with no imaging.

Conclusion

Implementing this protocol reduces the future burden on tertiary services, by empowering primary care physicians to re-refer low risk patients. The protocol is applicable across the UK and avoids diagnostic delay.

[Correlation between the Bethesda system for thyroid nodules and post-thyroidectomy histopathological diagnosis]

BACKGROUND

Thyroid nodules are a common clinical condition. Thyroid nodules may be identified with ultrasonography in roughly 50% of the population. The risk of malignancy varies between 4 and 15% of the nodules. Fine needle aspiration (FNA) with a cytopathology report using the Bethesda system is the most utilized methods to diagnose thyroid carcinoma.

MATERIAL AND MEHOTDS

A retrospective, descriptive study was performed to investigate the correlation between the cytopathology of the FNA biopsies, and the final histopathology after thyroidectomy.

RESULTS

A total of 128 nodules in 128 patients were studied; 24 males and 104 females. In the Bethesda category I, a 67% malignancy rate was reported, Bethesda II 14%, Bethesda III 28% for follicular lesions and 15% for atypia, Bethesda IV 36%, Bethesda V 79% and Bethesda VI 100%.

CONCLUSION

The Bethesda system has been widely adopted internationally and has become an unassailable tool for the pathologist and clinicians for the evaluation and management of thyroid nodules. Since its implementation in the ABC Medical Center, the Bethesda system has granted the institution with favorable and reproducible results.

Identification of Radioactive Iodine Refractory Differentiated Thyroid Cancer

Most differentiated thyroid cancer (DTC) patients have an excellent prognosis. However, about one-third of DTC patients with recurrent or metastatic disease lose the hallmark of specific iodine uptake initially or gradually and acquire radioactive iodine-refractory DTC (RAIR-DTC) with poor prognosis. Due to the potentially severe complications from unnecessarily repeated RAI therapy and encouraging progress of multiple targeted drugs for advanced RAIR-DTC patients, it has become crucial to identify RAIR-DTC early. In this review, we focus on the progress and controversies regarding the defining of RAIR-DTC, further with subsistent approaches and promising molecular nuclear medicine imaging in identifying RAIR-DTC, which may shed light on the proper management methodsof such patients.

Multifocal papillary carcinoma of the thyroid with heterotopic ossification and extramedullary hematopoiesis associated with a lipomatous follicular nodule

Heterotopic ossification has been described in papillary thyroid carcinoma in association with high incidence of extrathyroidal invasion, multifocality, lymph node metastasis, and older age. Nevertheless, it has not been described as a specific subtype of papillary thyroid carcinoma, because of its rarity. We described the case of an 80-year-old female patient, with familial history of papillary thyroid carcinoma. In the annual screening examination, she was diagnosed with thyroid nodules. The patient was submitted to a thyroidectomy because the fine needle aspiration cytology was positive for malignancy according to the Bethesda classification. The surgical specimen analyses showed a multifocal papillary carcinoma with one major lesion in the left lobe measuring 0.9 cm, and two small lesions (0.4 cm and 0.2 cm) in the right lobe. Only the biggest lesion in the right lobe had the osteoid matrix with rare osteoclasts and fat metaplasia with progenitor cells. There was perineural invasion, but vascular invasion was not identified. The margins were free and there was no extrathyroidal extension. In the left lobe there was an oncocytic nodule and a lipomatous follicular nodule. In recent years there has been a significant increase in the diagnosis of thyroid cancer, mainly because of the finding of microcarcinomas as a result of many requests for cervical image exams. Future studies may define (i) whether papillary thyroid carcinoma with heterotopic ossification is a true histological variant; (ii) the causes of that alteration; and (iii) eventual follow-up implications.

Papillary thyroid carcinoma in cervical lymph nodes with vanished thyroid gland after ablation of Graves' disease by radioactive iodine

Primary thyroid carcinoma after thyroid ablation by radioactive iodine is rare. We present a very rare condition of lateral apparent papillary thyroid carcinoma eight years after receiving radioactive iodine for thyrotoxicosis, which led to complete anatomical and functional involution of the thyroid gland.

Comparison of I-131 Biokinetics after Recombinant Human TSH Stimulation and Thyroid Hormone Withdrawal Measured by External Detector in Patients with Differentiated Thyroid Cancer

The aim of this study was to compare radioactive iodine (I-131) biokinetics after recombinant human TSH stimulation (rhTSH) and thyroid hormone withdrawal (THW) in patients with differentiated thyroid cancer (DTC). External effective dose rates were measured using external detectors and imaged quantitatively at the time of discharge from the isolation wards. We retrospectively analyzed 32 patients who had been diagnosed with DTC, papillary or follicular, and underwent remnant ablation after either rhTSH stimulation (n=22) or THW (n=10). The uptake of I-131 by remnant thyroid tissue was measured from 20.0 cm, 100.0 cm and 200.0 cm distances using a handheld external detector. The remnant thyroid tissue measured by the whole body images two to five days from administration was 10.7+26.0% (range 0.5 to 60.0%). The values measured at 20 cm were best correlated to the thyroid residual uptake measured by SPECT/CT. The half-lives of I-131washout (T1/2) in rhTSH group measured by external detector were shorter than those of THW group. T1/2 becomes longer when it was measured over longer distances. They were 10.9, 12.3 and 13.1 hours at distances of 20, 100, and 200 cm in rhTSH group, respectively. The TWH group showed 12.8, 14.9 and 17.7 hours, respectively. We conclude that I-131 biokinetics can be measured by external detector after high dose I-131 therapy for DTC. It showed that washout of I-131 was faster after rhTSH stimulation than THW, and slower in patients with distant metastasis than those without metastasis.

Robotic and Endoscopic Thyroid Surgery: Evolution and Advances

To minimize surgical morbidity and neck scarring, minimally invasive thyroidectomy and robotic/endoscopic thyroidectomy via cervical, axillary, anterior chest, breast, postauricular or transoral approaches have been developed over the past 20 years. In this article, we review the evolution of robotic and endoscopic thyroid surgery and recent advances. Among remote access approaches, the gasless transaxillary approach, bilateral axillo-breast approach, postauricular facelift approach, and transoral vestibular approach are in common use today. Each procedure has its own advantages and disadvantages. Therefore, we need to understand these advantages and limitations, and to select the appropriate method for each patient. The most significant advantage of remote access thyroidectomy is its excellent cosmesis. The complication rate is similar in patients undergoing a remote access approach and those undergoing conventional surgery if the former is performed by experienced surgeons. Operative time is significantly longer in remote access thyroidectomy. In conclusion, remote access thyroidectomy is feasible and its outcomes are comparable to those of conventional transcervical thyroidectomy in highly selected patients.

Thyroid cancer among female workers in Korea, 2007-2015

Background

Prevalence of thyroid cancer has been increasing rapidly worldwide, especially among women. There has been a debate as to whether such an increase represents consequences of over-diagnosis or a true increase. To find the occupational risk of Korean female workers in different industry sectors, we analyzed the data of Korean female workers.

Methods

National Female Worker Cohort data that contain information on total female workers were used for our analysis of prevalence of thyroid cancer (C73 according to KCD-5, 6 code) derived from National Health Insurance data. By combining industrial codes from National Health Insurance Service and those from Korea Workers' Compensation and Welfare Service, the classification of industrial codes became to consist of the total of thirty three representing both non-office (NO) and office (O) categories. Both an internal comparison among female workers within the cohort and an external comparison to compare female workers with Korean general female population were carried out.

Results

Among 149,258 female workers, 2,641 cases of thyroid cancers were identified. Differences in prevalence of thyroid cancer between female workers (40.5%) and general Korean female population (32.6%) were observed; however, the differences in prevalence of thyroid cancer between NO workers and O workers were not apparent. An analysis involving workers in Financial and insurance activities sector revealed that, standardized prevalence rate (SPR) of both NO (2.96, 95% CI = 2.01-4.20) and O workers (3.68, 95% CI = 3.10-4.33) increased significantly and that an AOR (adjusted odds ratio) increased marginally (1.38, 95% CI = 0.97-1.96). Further, when stratified in respect to the duration of employment, an AOR of female workers having been employed for more than 8 years showed a significant increase (1.63, 95% CI = 1.07-2.49).

Conclusions

Female workers had a higher risk of thyroid cancer than general female population but the difference between NO workers and O workers was not found to be significant in most industrial sectors. Further studies using data with information regarding specific occupational exposures are needed.

An Unusual Case of Papillary Thyroid Carcinoma Iodine-131 Avid Metastasis to the Adrenal Gland

SUMMARY – Papillary thyroid carcinoma (PTC) is considered one of the most favorable tumors, indolent, with rare distant dissemination. Lungs and bones are the most common metastatic sites. Unusual sites of PTC distant metastases are extremely rare. Brain, liver, skin, kidney, pancreas, and adrenal gland PTC metastases have been sporadically reported in the literature. An 86-year-old female patient underwent total thyroidectomy and neck dissection due to PTC. Postoperative whole body iodine-131 scintigraphy with I-131 SPECT/CT of the abdomen revealed radioiodne avid left adrenal gland metastasis together with high postoperative serum thyroglobulin (Tg) value of more than 5000 µg/L and high serum Tg antibodies. Considering the above-mentioned findings, patient‘s age and multiple comorbidities, radioiodine therapy was applied. PTC metastases to the adrenal gland are extremely rare, and to our knowledge, only nine cases have been reported in the literature. This case report complements rare examples of unusual PTC metastases.

The MEK1/2 Inhibitor AZD6244 Sensitizes BRAF-Mutant Thyroid Cancer to Vemurafenib

Background

BRAF^V600E mutation occurs in approximately 45% of papillary thyroid cancer (PTC) cases, and 25% of anaplastic thyroid cancer (ATC) cases. Vemurafenib/PLX4032, a selective BRAF inhibitor, suppresses extracellular signal-regulated kinase kinase/extracellular signal-regulated kinase 1/2 (MEK/ERK1/2) signaling and shows beneficial effects in patients with metastatic melanoma harboring the BRAFV600E mutation. However, the response to vemurafenib is limited in BRAF-mutant thyroid cancer. The present study evaluated the effect of vemurafenib in combination with the selective MEK1/2 inhibitor AZD6244 on cell survival and explored the mechanism underlying the combined effect of vemurafenib and AZD6244 on thyroid cancer cells harboring BRAFV600E.

Material/Methods

Thyroid cancer 8505C and BCPAP cells harboring the BRAFV600E mutation were exposed to vemurafenib (0.01, 0.1, and 1 μM) and AZD6244 (0.01, 0.1, and 1 μM) alone or in the indicated combinations for the indicated times. Cell viability was detected by the MTT assay. Cell cycle distribution and induction of apoptosis were detected by flow cytometry. The expression of cyclin D1, P27, (P)-ERK1/2 was evaluated by Western blotting. The effect of vemurafenib or AZD6244 or their combination on the growth of 8505C cells was examined in orthotopic xenograft mouse models in vivo.

Results

Vemurafenib alone did not increase cell apoptosis, whereas it decreased cell viability by promoting cell cycle arrest in BCPAP and 8505C cells. AZD6244 alone increased cell apoptosis by inducing cell cycle arrest in BCPAP and 8505C cells. Combination treatment with AZD6244 and vemurafenib significantly decreased cell viability and increased apoptosis in both BCPAP and 8505C cells compared with the effects of each drug alone. AZD6244 alone abolished phospho-ERK1/2 (pERK1/2) expression at 48 h, whereas vemurafenib alone downregulated pERK1/2 at 4–6 h, with rapid recovery of expression, reaching the highest level at 24–48 h. Combined treatment for 48 h completely inhibited pERK1/2 expression. Combination treatment with vemurafenib and AZD6244 inhibited cell growth and induced apoptosis by causing cell-cycle arrest, with the corresponding changes in the expression of the cell cycle regulators p27^Kip1 and cyclin D1. Co-administration of vemurafenib and AZD6244 in vivo had a significant synergistic antitumor effect in a nude mouse model.

Conclusions

Vemurafenib activated pERK1/2 and induced vemurafenib resistance in thyroid cancer cells. Combination treatment with vemurafenib and AZD6244 inhibited ERK signaling and caused cell cycle arrest, resulting in cell growth inhibition. Combination treatment in patients with thyroid cancer harboring the BRAFV600E mutation may overcome vemurafenib resistance and enhance the therapeutic effect.

Malignancy Rates in Thyroid Nodules Classified as Bethesda Categories III and IV: Retrospective Data from a Tertiary Center

BACKGROUND

Thyroid fine needle aspiration (FNA) has a well-established role in the diagnosis of thyroid nodules, and the "Bethesda system for reporting thyroid cytopathology" is used to interpret FNA results. Bethesda categories III and IV encompass varying risks of malignancy. In addition, there is some debate in the literature about how to select among many acceptable treatment approaches.

OBJECTIVES

To establish an association between these 2 cytological categories and malignancy rates in patients treated in a referral tertiary cancer center, where surgical treatment is recommended for all these patients.

METHODS

A total of 615 thyroid nodules (582 patients) were included in this retrospective study. There were 478 nodules that were classified as Bethesda category III and 137 nodules as Bethesda category IV. Electronic records were reviewed to establish a correlation between the FNA cytological results and the final histopathological analyses. Incidentally detected carcinomas were considered separately.

RESULTS

Among the bethesda category III group, 75 malignant nodules (15.7%) were coincident with the target nodule (74 patients, 16.2%). Incidental carcinomas were found in 13.8% of these patients. The remaining 403 (84.3%) target nodules were benign. Among the bethesda category IV nodules, 23 malignant nodules (16.8%) were coincident with the target nodule. Incidental carcinomas were found in 25 patients (19.7%). The other 114 target nodules were benign. A total of 46 patients (52.3%) had carcinomas in the thyroid lobe contralateral to the one containing the target nodule, and 40 patients (45.5%) had carcinomas exclusively in the contralateral lobe.

CONCLUSIONS

We observed a 16% rate of malignancy in nodules classified as bethesda category III and 17% among bethesda category IV. When incidental carcinomas were included, the rates of malignancy doubled.

Thrombosis in Thyroid Cancer

BACKGROUND

The number of studies on venous thromboembolism (VTE) and thyroid cancer is very scarce and existing data are contradictory. This paper reviews VTE in thyroid cancer.

METHODS

The following words were used for a comprehensive literature review using MEDLINE database: Blood coagulation factors; thyroid hormones; blood coagulation tests; venous thromboembolism; receptors thyroid hormone; hemostasis; fibrinolysis; bleeding; blood coagulation disorders; thyroid neoplasms; Thyroid cancer, papillary; Thyroid cancer, follicular; Thyroid carcinoma, anaplastic; Thyroid cancer, Hurthle cell; Familial medullary thyroid carcinoma; venous thrombosis; Pulmonary embolism; Blood coagulation factors. The studies, which include any changes in hemostasis and thyroid cancer were included and reviewed.

RESULTS

Although few studies have shown a possible increase in VTE occurrence in thyroid cancer in patients ≥ 60 years old and in proximity to cancer diagnosis, other studies could not find any difference compared to general population. New thyroid cancer classification excluding common subtype(s) with benign nature, may affect the results of the future studies on association of VTE and thyroid cancer.

CONCLUSIONS

Prospective studies on the occurrence of VTE in various types and severities of thyroid cancer and in different age groups are warranted, as the results would affect clinical practice on the necessity of usage of anticoagulants in some thyroid cancer groups.

Hemostasis in Overt and Subclinical Hyperthyroidism

CONTEXT

There are contradictory results on the effect of hyperthyroidism on hemostasis. Inadequate population-based studies limited their clinical implications, mainly on the risk of venous thromboembolism (VTE). The present review focuses on hemostatic changes in overt and subclinical hyperthyroidism.

METHODS

A systematic literature search was conducted employing MEDLINE database. The following words were used for the search: Hyperthyroidism; thyrotoxicosis; Graves disease; goiter, nodular; hemostasis; blood coagulation factors; blood coagulation disorders; venous thromboembolism; bleeding; fibrinolysis. The articles that were related to hyperthyroidism and hemostasis are used in this manuscript.

RESULTS

Hyperthyroidism, either overt or subclinical, renders a hypercoagulable state, although there are several studies with contradictory findings in the literature. Hypercoagulability may be caused by an increase in the level of various coagulation factors such as factor (F) VIII, FX, FIX, von Willebrand F (vWF), and fibrinogen, while hypofibrinolysis by changes in coagulation parameters such as a decrease in plasmin and plasmin activator or an increase in α2-antiplasmin, plasminogen activator inhibitor-1 and thrombin activatable fibrinolysis inhibitor.

CONCLUSIONS

Although many reports are in favor of a hypercoagulable state in overt hyperthyroidism but this finding at the biochemical level and its clinical implication, on the occurrence of VTE, has yet to be confirmed.

The role of race in thyroid cancer: systematic review

BACKGROUND

The incidence of thyroid cancer is increasing. There is conflicting evidence as to why. However, studies suggest that it is not an apparent increase resulting from enhanced diagnostic practices, but a true increase with more affected patients. This study aimed to assess racial variation in thyroid cancer.

METHOD

A narrative systematic review of the literature was conducted.

RESULTS

Eight retrospective cohort studies were identified, comprising 611 777 adult patients. Variations exist between racial groups, which are also dependent on gender; white patients have a slightly higher male population when compared to their counterparts. Black and white patients have a higher proportion of follicular cancer. Hispanics were younger at the age of diagnosis. Outcomes are greatly affected by socioeconomic status.

CONCLUSION

This study identified many gaps in the way that these types of data are presented. A more concise manner of reporting, with individual-level risk factors, is recommended.

Incidental nodal metastasis of differentiated thyroid carcinoma in neck dissection specimens from head and neck cancer patients

BACKGROUND

Occult differentiated thyroid carcinomas are not uncommon. The initial presentation of a thyroid carcinoma is often detection of a metastatic cervical lymph node.

METHODS

A retrospective review was performed of the medical records of 304 patients who underwent neck dissection between 1996 and 2008 for squamous cell carcinoma of the head and neck.

RESULTS

Ten patients (3.3 per cent) had nodal metastasis originating from papillary thyroid cancer. All of these patients underwent thyroidectomy and post-operative 131iodine radiometabolic therapy. No patient developed a thyroid tumour after surgery.

CONCLUSION

Despite its metastatic spread, thyroid cancer does not affect the overall prognosis of patients who are already being treated for a more aggressive malignancy. However, in otherwise healthy patients, it is worth treating this second malignancy to avoid potential complications related to local disease or metastatic thyroid cancer.

Observation versus thyroidectomy for papillary thyroid microcarcinoma in the elderly

OBJECTIVE

To compare the effectiveness of non-surgical versus surgical therapy in elderly patients with papillary thyroid microcarcinoma.

METHODS

The study cohort included 2323 elderly patients (aged 65 years and over) diagnosed with papillary thyroid microcarcinoma between 1988 and 2009, identified in the Surveillance, Epidemiology, and End Results 18 database of the National Cancer Institute.

RESULTS

The five-year overall survival rate was 23 per cent for non-surgical patients compared with 91 per cent for surgical patients (p < 0.0001). Unadjusted analysis revealed significantly improved survival in surgical patients compared with non-surgical patients (hazard ratio = 0.06; p < 0.0001). Propensity score analysis also revealed significantly improved survival in surgical patients compared with non-surgical patients (hazard ratio = 0.11; p < 0.0001).

CONCLUSION

Thyroidectomy appears to provide a survival benefit for elderly patients with papillary thyroid microcarcinoma. High-quality prospective studies are needed to better evaluate the comparative effectiveness of immediate thyroidectomy versus observation for elderly patients with papillary thyroid microcarcinoma.

Racial disparities in papillary thyroid microcarcinoma survival

OBJECTIVE

To evaluate the impact of race on survival in patients with papillary thyroid microcarcinoma.

METHODS

The study cohort included 17 668 patients diagnosed with papillary thyroid microcarcinoma between 1988 and 2009, identified in the Surveillance, Epidemiology, and End Results 18 database of the National Cancer Institute.

RESULTS

Black patients had lower overall survival than other racial groups (p < 0.001). Black patients had significantly worse overall survival (hazard ratio = 2.59) after adjusting for sex, marital status, age, year of diagnosis, multifocal disease and type of surgery. A subset analysis of Black patients revealed no significant difference in overall survival for total thyroidectomy versus lobectomy (p = 0.15).

CONCLUSION

Black race is a negative prognostic factor in thyroid cancer, which cannot be explained by advanced disease stage. Further research on mechanisms by which race affects survival is needed to reveal areas of opportunity for interventions aimed at reducing health disparities in cancer care.

Diagnostic Accuracy of Contrast-Enhanced Ultrasound Enhancement Patterns for Thyroid Nodules

Background

The aim of this study was to investigate the accuracy of contrast-enhanced ultrasound (CEUS) enhancement patterns in the assessment of thyroid nodules.

Material/Methods

A total of 158 patients with suspected thyroid cancer underwent conventional ultrasound (US) and CEUS examinations. The contrast enhancement patterns of the lesions, including the peripheries of the lesions, were assessed by CEUS scans. The relationship between the size of the lesions and the degree of enhancement was also studied. US- and/or CEUS-guided biopsy was used to obtain specimens for histopathological diagnosis.

Results

The final data included 148 patients with 157 lesions. Seventy-five patients had 82 malignant lesions and 73 patients had 75 benign lesions. Peripheral ring enhancement was seen in 40 lesions. The differences of enhancement patterns and peripheral rings between benign and malignant nodules were significant (p=0.000, 0.000). The diagnostic sensitivity, specificity, and accuracy for malignant were 88%, 65.33%, and 88.32%, respectively, for CEUS, whereas they were 98.33%, 42.67%, and 71.97%, respectively, for TC by conventional US. The misdiagnosis rate by conventional US was 57.33% and 34.67% by CEUS (p=0.005). With regard to the size of lesions, a significant difference was found between low-enhancement, iso-enhancement, high-enhancement, iso-enhancement with no-enhancement area and no-enhancement (p=0.000).

Conclusions

In patients with suspicious US characteristics, CEUS had high specificity and contributed to establishing the diagnosis. Therefore, CEUS could avoid unnecessary biopsy.

Preoperative Lymph Node Staging by FDG PET/CT With Contrast Enhancement for Thyroid Cancer: A Multicenter Study and Comparison With Neck CT

Objectives

The purpose of this study was to compare lymph node (LN) staging using ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) with contrast-enhancement (CE) PET/CT and contrast-enhanced neck CT (neck CT) in patients with thyroid cancer with level-by-level comparison with various factors.

Methods

This was a retrospective multicenter study. A total of 85 patients were enrolled. Patients who underwent a preoperative evaluation by CE PET/CT and neck CT for thyroid cancer were enrolled. The gold standard for LN was the combination of surgical pathology and clinical follow-up. We compared CE PET/CT with neck CT using a level-by-level method. Factors, including age, sex, camera, arm position, tumor size, extra-thyroidal extension, tumor location, number of primary tumors, primary tumor maximum standardized uptake value, and the interval from scan to operation were also analyzed.

Results

Overall accuracy was 81.2% for CE PET/CT and 68.2% for neck CT. CE PET/CT was more sensitive than neck CT (65.8% vs. 44.7%). Also, CE PET/CT showed higher negative predictive value (77.2% vs. 66.1%). CE PET/CT showed good agreement with the gold standard (weighted kappa [κ], 0.7) for differentiating N0, N1a, and N1b, whereas neck CT showed moderate agreement (weighted κ, 0.5). CE PET/CT showed better agreement for the number of levels involved with the gold standard (weighted κ, 0.7) than that of neck CT with the gold standard (weighted κ, 0.5). The accuracies for differentiating N0, N1a, and N1b were 81.2% for CE PET/CT and 68.2% for neck CT. Level-by-level analysis showed that CE PET/CT was more sensitive and has higher negative predictive value for detecting ipsilateral level IV and level VI LNs than neck CT. Other analyzed factors were not related to accuracies of both modalities.

Conclusion

CE PET/CT was more sensitive and reliable than neck CT for preoperative LN staging in patients with thyroid cancer.

Jugular Vein Invasion Diagnosis and Prognosis in Thyroid Carcinomas

Diagnosis of venous jugular invasion by means of traditional imaging is very rarely reported in the literature. Doppler ultrasound definitively helps to diagnose the tumor thrombus, the extent, and helps in redefining the TNM stage of such an aggressive thyroid tumor.

Radioprotective Effect of Epigallocatechin-3-Gallate on Salivary Gland Dysfunction After Radioiodine Ablation in a Murine Model

Objectives.

Radioiodine (RI) therapy is known to subject cellular components of salivary glands (SG) to oxidative stress leading to SG dysfunction. However, the protective effects of antioxidants on RI-induced SG damage have not been well investigated. The authors investigated the morphometric and functional effects of epigallocatechin-3-gallate (EGCG) administered prior to RI therapy and compared this with the effects of amifostine (a well-known antioxidant) in a murine model of RI sialadenitis.

Methods.

Four-week-old female C57BL/6 mice (n=48) were divided into four groups; a normal control group, a RI-treated group (0.01 mCi/g mouse, orally), an EGCG and RI-treated group, and an amifostine and RI-treated group. Animals in these groups were divided into 3 subgroups and euthanized at 15, 30, and 90 days post-RI treatment. Salivary flow rates and lag times were measured, and morphologic and histologic examinations and TUNEL (terminal deoxynucleotidyl transferase biotin-dUDP nick end labeling) assays were performed. Changes in salivary ^99mTc pertechnetate uptake and excretion were followed by single-photon emission computed tomography.

Results.

Salivary flow rates and lag times to salivation in the EGCG or amifostine groups were better than in the RI-treated group. Histologic examinations of SGs in the EGCG or amifostine group showed more mucin-rich parenchyma and less periductal fibrosis than in the RI-treated group. Fewer apoptotic cells were observed in acini, ducts, and among endothelial cells in the EGCG or amifostine group than in the RI group. In addition, patterns of ^99mTc pertechnetate excretion were quite different in the EGCG or amifostine group than in the RI group.

Conclusion.

EGCG supplementation before RI therapy could protect from RI-induced SG damage in a manner comparable to amifostine, and thus, offers a possible means of preventing SG damage by RI.

Ultrasonographic Characteristics of the Follicular Variant Papillary Thyroid Cancer According to the Tumor Size

Follicular variant papillary thyroid cancer (FVPTC) is the second most common subtype after conventional PTC. We compared ultrasonographic (US) features of FVPTC to those of conventional PTC according to tumor size. We reviewed US findings, pathologic reports, and medical charts of 249 PTC patients with surgically proven disease (83 FVPTCs, 166 conventional PTCs) at our institution from January 2007 to December 2012. FVPTCs were divided into PTC-like and follicular neoplasm (FN)-like based on sonographic characteristics. PTC-like features were defined as having at least one malignant feature (taller-than-wide shape, infiltrative margin, marked hypoechogenicity, and micro-calcifications), whereas FN-like cancers showed oval solid features without malignant features. FVPTCs showed a higher rate of FN-like features than conventional PTCs. Of 166 conventional PTCs, 13 (7.8%) had FN-like features and 153 (92.2%) had PTC-like features, whereas of the 83 FVPTCs, 31 (37.3%) had FN-like features and 52 (62.7%) had PTC-like features. Macro-FVPTCs showed a higher rate of FN-like features than micro-FVPTCs (P < 0.001). Of 21 macro-FVPTCs, 18 (85.7%) had FN-like features and 3 (14.3%) had PTC-like features, whereas of the 62 micro-FVPTCs, 13 (21%) had FN-like features and 49 (79%) had PTC-like features. There were no differences in multifocality, extrathyroidal invasion, and lymph node metastasis between PTC-like FVPTCs and FN-like FVPTCs. FVPTCs showed fewer sonographic malignant features than conventional PTCs. In particular, FVPTCs larger than 1 cm had a more frequent benign sonographic appearance. Therefore, if fine-needle aspiration result is suspicious for PTC in a nodule larger than 1 cm with no suspicious US features, the possibility of FVPTC might be considered.

Primary tumour characteristics predict the invasiveness of lymph node metastases in papillary thyroid carcinoma patients

OBJECTIVE

This study evaluated whether primary tumour characteristics are associated with specific features of metastatic lymph nodes in papillary thyroid carcinoma patients.

METHOD

A retrospective review of 411 patients with pathologically diagnosed cervical lymph node metastasis was conducted.

RESULTS

A metastatic lymph node focus size of at least 2 mm was independently associated with a primary tumour size of at least 1 cm (hazard ratio 1.962) and with male sex (hazard ratio 1.947). A number of at least five lymph node metastases was independently associated with a primary tumour size of at least 1 cm (hazard ratio 2.863), extrathyroidal extension (hazard ratio 1.737) and male sex (hazard ratio 1.689). Extranodal extension was independently associated with a primary tumour size of at least 1 cm (hazard ratio 2.288), extrathyroidal extension (2.201) and male sex (hazard ratio 1.733).

CONCLUSION

Primary papillary thyroid carcinoma characteristics are related to the pathological features of lymph node metastases.

A Rare Complication of the Thyroid Malignancies: Jugular Vein Invasion

Background

Unilateral invasion of the internal jugular vein (IJV) after subtotal thyroidectomy caused by local recurrence of papillary thyroid carcinoma is extremely rare. We report a case of papillary thyroid carcinoma which invades IJV with hypervascular tumor thrombus.

Case Report

We report a case of a 52-year-old woman with a history of previous thyroid operation who presented with a 2-month history of a painless, growing, hard, solitary mass on the left side of the neck. Clinical examination revealed also ipsilateral cervical lymphadenopathy. Radiological examination showed a necrotic and cystic mass arising from the operated area extending and invading the left jugular vein wall with hypervascular tumor thrombus. Cytological examination of the mass confirmed a papillary thyroid carcinoma (PTC) and enlarged metastatic lymph nodes. Therefore, total thyroidectomy with left neck dissection and segmental resection of the left internal jugular vein were performed, and the tumor thrombus was cleared successfully.

Conclusions

Invasion of IJV with hypervascular tumor thrombosis is an extremely rare condition in papillary thyroid carcinoma. Thrombosis of IJV is probably underdiagnosed. Early-stage diagnosis is important for long-term survival rates.

Use of tracheal stenting in the palliation of anaplastic thyroid carcinoma: tertiary centre experience

BACKGROUND

Anaplastic thyroid carcinoma is rare but carries a poor prognosis. Anaplastic thyroid carcinoma leads to tracheal compression, airway compromise and eventually death. Airway compromise, a particularly distressing symptom, can be palliated with tracheal stenting.

METHOD

A retrospective case note analysis was conducted of patients diagnosed with anaplastic thyroid carcinoma between July 2003 and July 2013.

RESULTS

Twelve patients with anaplastic thyroid carcinoma were identified. Four patients underwent palliative tracheal stenting. Three patients had no dyspnoea at the time of stenting. Two stented patients subsequently developed dyspnoea secondary to stent migration; this was managed successfully with stent exchange. The other stented patient remained asymptomatic with regards to dyspnoea. All non-stented patients died with or from airway compromise.

CONCLUSION

Tracheal stenting is a relatively safe and effective method for palliation of distressing airway symptoms in patients with anaplastic thyroid carcinoma. Early prophylactic tracheal stenting in anaplastic thyroid carcinoma may be an effective option to prevent development of airway compromise as the disease progresses.

Stem cell biology in thyroid cancer: Insights for novel therapies

Currently, thyroid cancer is one of the most common endocrine cancer in the United States. A recent involvement of sub-population of stem cells, cancer stem cells, has been proposed in different histological types of thyroid cancer. Because of their ability of self-renewal and differentiation into various specialized cells in the body, these putative cells drive tumor genesis, metastatic activity and are responsible to provide chemo- and radioresistant nature to the cancer cells in the thyroid gland. Our Review was conducted from previously published literature to provide latest apprises to investigate the role of embryonic, somatic and cancer stem cells, and discusses the hypothesis of epithelial-mesenchymal transition. Different methods for their identification and isolation through stemness markers using various in vivo and in vitro methods such as flow cytometry, thyrosphere formation assay, aldehyde dehydrogenase activity and ATP-binding cassette sub-family G member 2 efflux-pump mediated Hoechst 33342 dye exclusion have been discussed. The review also outlines various setbacks that still remain to target these tumor initiating cells. Future perspectives of therapeutic strategies and their potential to treat advanced stages of thyroid cancer are also disclosed in this review.

Metastasis of colon cancer to medullary thyroid carcinoma: a case report

Metastasis to the primary thyroid carcinoma is extremely rare. We report here a case of colonic adenocarcinoma metastasis to medullary thyroid carcinoma in a 53-yr old man with a history of colon cancer. He showed a nodular lesion, suggesting malignancy in the thyroid gland, in a follow-up examination after colon cancer surgery. Fine needle aspiration biopsy (FNAB) of the thyroid gland showed tumor cell clusters, which was suspected to be medullary thyroid carcinoma (MTC). The patient underwent a total thyroidectomy. Using several specific immunohistochemical stains, the patient was diagnosed with colonic adenocarcinoma metastasis to MTC. To the best of our knowledge, the present patient is the first case of colonic adenocarcinoma metastasizing to MTC. Although tumor-tumor metastasis to primary thyroid carcinoma is very rare, we still should consider metastasis to the thyroid gland, when a patient with a history of other malignancy presents with a new thyroid finding.

Frequency of thyroid incidentalomas in Karachi population

Objectives: The aim of this study was to determine frequency of thyroid incidentalomas (TI) through ultrasound (US) and its association with age, gender and ethnicities.

Methods: It was a cross-sectional study. Total 269 adults who were asymptomatic for thyroid disease aged 21 years and above underwent ultrasound examination of their thyroid.

Results: Frequency of TI found was 21%. TI was detected in 25% of females and 16% males (P= 0.078). 61% had thyroid nodules (TNs) in one lobe (right, left or isthmus) and 39% had TNs in more than one location. About 55% had single TN and 45% had multiple TNs. 38% had TNs greater than 1cm while 57% had TNs smaller than 1 cm. 5% had TNs greater and smaller than 1 cm. TI was equally common in individuals of different ethinicities (P= 0.758).

Conclusion: Frequency of thyroid incidentalomas found in our study was higher than most of the other iodine sufficient states. Unlike other studies, incidentalomas were equally common in both the genders of our study. This may be due to the previous iodine deficient status of Pakistan which was prevalent. However further studies on the same topic will help us in identifying the correct status of thyroid incidentalomas if Pakistan retains it’s status as an iodine sufficient state.

Clinicopathological features of rare BRAF mutations in Korean thyroid cancer patients

The most common BRAF mutation in thyroid cancer is c.1799T>A (p.Val600Glu), and other BRAF mutations are rarely reported. We investigated the clinicopathological features of thyroid cancer with rare BRAF mutations. A total of 2,763 patients with thyroid cancer underwent molecular testing by direct DNA sequencing for mutations in BRAF exon 15. Among them, 2,110 (76.4%) had BRAF mutations. The c.1799T>A mutation was found in 2,093 (76.9%) of 2,722 papillary carcinomas and in one of 7 medullary carcinomas. Sixteen cases (0.76%) harbored rare mutation types. Five cases had single-nucleotide substitutions, 5 cases had small in-frame deletion or insertion, and one harbored a two-nucleotide substitution. Of these mutations, 2 were novel (c.1797_1798insGAGACTACA, c.[1799T>A; 1801_1812del]). The c.1801A>G mutation was identified in 4 follicular variant papillary carcinomas and one follicular carcinoma. None of the patients with the c.1801A>G mutation showed extrathyroidal extension or lymph node metastasis. The prevalence of rare BRAF mutations was 0.76% of all BRAF-positive thyroid cancers, and the rare mutations were associated with less aggressive pathologic features. Although BRAF mutations are detected exclusively in papillary carcinoma, they are also found in medullary carcinoma and follicular carcinoma. [Corrected]

The effectiveness of recombinant human thyroid-stimulating hormone versus thyroid hormone withdrawal prior to radioiodine remnant ablation in thyroid cancer: a meta-analysis of randomized controlled trials

We evaluated the efficacy of recombinant human thyroid-stimulating hormone (rhTSH) versus thyroid hormone withdrawal (THW) prior to radioiodine remnant ablation (RRA) in thyroid cancer. A systematic search of MEDLINE, EMBASE, the Cochrane Library, and SCOPUS was performed. Randomized controlled trials that compared ablation success between rhTSH and THW at 6 to 12 months following RRA were included in this study. Six trials with a total of 1,660 patients were included. When ablation success was defined as a thyroglobulin (Tg) cutoff of 1 ng/mL (risk ratio, 0.99; 95% confidence interval, 0.96-1.03) or a Tg cutoff of 1 ng/mL plus imaging modality (RR 0.97; 0.90-1.05), the results of rhTSH and THW were similar. There were no significant differences when ablation success was defined as a Tg cutoff of 2 ng/mL (RR 1.03; 0.95-1.11) or a Tg cutoff of 2 ng/mL plus imaging modality (RR 1.02; 0.95-1.09). When a negative (131)I-whole body scan was used solely as the definition of ablation success, the effects of rhTSH and THW were not significantly different (RR 0.97; 0.93-1.02). Therefore, ablation success rates are comparable when RRA is prepared by either rhTSH or THW.

The association between the socioeconomic status and thyroid cancer prevalence; based on the Korean National Health and Nutrition Examination Survey 2010-2011

The incidence of thyroid cancer has recently increased in most industrialized countries, including Korea. To date, few studies have examined the association between thyroid cancer and socioeconomic status (SES). The current study was based on data collected from a total of 12,276 subjects (5,277 men and 6,999 women) by the Korean National Health and Nutrition Examination Survey (KNHANES) between 2010 and 2011. Univariate and multivariate logistic regression analysis revealed that older age (odds ration [OR], 1.03; 95% confidence interval [CI], 1.00-1.05), being female (OR, 8.16; 95%CI, 2.99-22.24), being overweight (OR, 1.04; 95%CI, 1.01-1.06), monthly household income (OR, 3.27; 95%CI, 1.16-9.20 for medium-highest household income vs lowest household income; OR, 3.30; 95%CI, 1.16-9.34 for highest household income vs lowest household income), educational level (OR, 2.74; 95%CI, 1.16-6.46 for 10-12 yr vs < 7 yr) and alcohol consumption (OR, 1.89; 95%CI 1.08-3.32) were significant risk factors for thyroid cancer. Our results indicate that the recent increase in thyroid cancer is attributable to better early detection rather than to any increase in actual prevalence.