Natural history, treatment, and course of papillary thyroid carcinoma

Papillary thyroid carcinoma: A bibliometric analysis of the top 100 cited articles

Objectives

To describe the current trends and key themes that are shaping the literature surrounding papillary thyroid carcinoma.

Methods

The Thomson Reuters Web of Science citation database was used to identify manuscripts relevant to papillary thyroid carcinoma. These were then subdivided into title, author, journal, publication date, theme, and manuscript types. Themes were then identified.

Results

A total of 1506 manuscripts were returned. The mean citation number was 163 (range 885-74), with the highest citation rate of 73.5. The highest impact factor was JAMA (impact factor of 56.27). 85% were original research, 10% review articles, and 5% were guidelines. The highest number of manuscripts were published in South Korea (21%).

Conclusions

This bibliometric analysis describes the most influential papers published in the topic of papillary thyroid carcinoma. Historic key themes have been endocrinology and metabolism, followed by surgical management and oncology (subdivided into surgery, pathology, radiology and public health/epidemiology). South Korea leads the world with the largest number of publications in this field; with an incidence rate of papillary thyroid carcinoma that is significantly higher than most parts of the world. Despite concerns with overdiagnosis, a collaborative radiological team skilled in ultrasonography of the neck appears to be of great value to the workup of thyroid cancers.

Infiltration of nanocarbon into the trachea during thyroidectomy surgery: case series and literature review

Introduction

The presence of metastatic disease in the cervical lymph nodes can affect the recurrence and survival of patients with thyroid cancer. Parathyroid gland injury during surgery can result in hypoparathyroidism, particularly with total thyroidectomy. Injection of carbon nanoparticles into the thyroid will label draining lymph nodes and aid in the visualization of metastatic cervical lymph nodes during a radical operation, sparing accidental damage to the parathyroid glands. Although reported to be useful during surgery, the safety of nanocarbon particles has rarely been investigated, and adverse side effects need to be studied.

Case presentation

The author describes five patients with thyroid cancer who had carbon secretions in the trachea or mucosa after carbon nanoparticles were injected into the thyroid. A patient with carbon secretions in the trachea mucosa recovered but had progressive dyspnoea. Surgical treatment was performed, and a mass was found in the trachea mucosa. After excluding all other possibilities, the author concluded that the mass was caused by nanocarbon suspension.

Discussion

To the author's knowledge, there are no reports on nanocarbon suspension into the mucosa and no consensus has yet been reached on the precise injection site, depth, or dose for injecting carbon nanoparticles before thyroidectomy.

Conclusion

The author suggests that the most appropriate injection depth of nanocarbon suspensions should be no more than 3 mm of the thyroid gland thickness to avoid deep injection into the trachea.

Impact of Tumor Size on Prognosis in Differentiated Thyroid Cancer with Gross Extrathyroidal Extension to Strap Muscles: Redefining T3b

The prognostic significance of tumor size in T3b differentiated thyroid cancer (DTC) remains debated and underexplored. This study aimed to examine the varying impact of T3b based on tumor size, analyzing disease-specific survival, disease-free survival, and overall survival. A retrospective review of 6282 DTC patients who underwent thyroid surgery at Seoul St. Mary's Hospital from September 2000 to December 2017 was conducted. T3b was classified into three subcategories, T3b-1 (≤2 cm), T3b-2 (2-4 cm), and T3b-3 (>4 cm), using the same size criteria for T1, T2, and T3a. T3b-1 showed no significant difference in disease specific survival compared to T1, and both disease-free and disease-specific survival curves were sequentially ranked as T1, T3b-1, T2, T3a, T3b-2, and T3b-3. The modified T category, reclassifying T3b-1 as T1, demonstrated superior staging performance compared to the classic T category (c-index: 0.8961 vs. 0.8959 and AUC: 0.8573 vs. 0.8518). Tumors measuring 2 cm or less within the T3b category may require downstaging, and a modified T category could improve the precision of prognostic staging compared to the current T category.

Modeling Thyroid Cancer Epidemiology in the United States Using Papillary Thyroid Carcinoma Microsimulation Model

OBJECTIVES

Thyroid cancer incidence increased over 200% from 1992 to 2018, whereas mortality rates had not increased proportionately. The increased incidence has been attributed primarily to the detection of subclinical disease, raising important questions related to thyroid cancer control. We developed the Papillary Thyroid Carcinoma Microsimulation model (PATCAM) to answer them, including the impact of overdiagnosis on thyroid cancer incidence.

METHODS

PATCAM simulates individuals from age 15 until death in birth cohorts starting from 1975 using 4 inter-related components, including natural history, detection, post-diagnosis, and other-cause mortality. PATCAM was built using high-quality data and calibrated against observed age-, sex-, and stage-specific incidence in the United States as reported by the Surveillance, Epidemiology, and End Results database. PATCAM was validated against US thyroid cancer mortality and 3 active surveillance studies, including the largest and longest running thyroid cancer active surveillance cohort in the world (from Japan) and 2 from the United States.

RESULTS

PATCAM successfully replicated age- and stage-specific papillary thyroid cancers (PTC) incidence and mean tumor size at diagnosis and PTC mortality in the United States between 1975 and 2015. PATCAM accurately predicted the proportion of tumors that grew more than 3 mm and 5 mm in 5 years and 10 years, aligning with the 95% confidence intervals of the reported rates from active surveillance studies in most cases.

CONCLUSIONS

PATCAM successfully reproduced observed US thyroid cancer incidence and mortality over time and was externally validated. PATCAM can be used to identify factors that influence the detection of subclinical PTCs.

Radioactive iodine administration is not associated with improved disease-specific survival in classic papillary thyroid carcinoma greater than 4 cm confined to the thyroid

BACKGROUND

We aimed to evaluate the impact of radioactive iodine on disease-specific survival in intrathyroidal (N0M0) papillary thyroid carcinoma >4 cm, given conflicting data in the American Thyroid Association guidelines regarding their management.

METHODS

The Surveillance, Epidemiology, and End Results database was queried for N0M0 classic papillary thyroid carcinoma >4 cm. Kaplan-Meier estimates were performed to compare disease-specific survival between radioactive iodine-treated and untreated groups. A multivariable Cox regression was performed to identify predictors of disease-specific survival.

RESULTS

There were more patients aged ≥55 (41.7% vs 32.3%, P = .001) and fewer multifocal tumors (25.3% vs 30.6%, P = .006) in the no radioactive iodine group. Ten-year disease-specific survival was similar between the radioactive iodine treated and untreated groups (97.2% vs 95.6%, P = .34). Radioactive iodine was not associated with a significant disease-specific survival benefit (adjusted hazard ratio = 0.78, confidence interval [0.39-1.58], P = .49). Age ≥55 (adjusted hazard ratio = 3.50, confidence interval [1.69-7.26], P = .001) and larger tumor size (adjusted hazard ratio = 1.04, confidence interval [1.02-1.06], P < .001) were associated with an increased risk of disease-specific death. Subgroup analyses did not demonstrate improved disease-specific survival with radioactive iodine in patients ≥55 and in tumors >5 cm.

CONCLUSION

Adjuvant radioactive iodine administration in classic papillary thyroid carcinoma >4 cm confined to the thyroid did not significantly impact disease-specific survival. Thus, these patients may not require routine treatment with adjuvant radioactive iodine.

Analysis of preoperative computed tomography radiomics and clinical factors for predicting postsurgical recurrence of papillary thyroid carcinoma

BACKGROUND

Postsurgical recurrence is of great concern for papillary thyroid carcinoma (PTC). We aim to investigate the value of computed tomography (CT)-based radiomics features and conventional clinical factors in predicting the recurrence of PTC.

METHODS

Two-hundred and eighty patients with PTC were retrospectively enrolled and divided into training and validation cohorts at a 6:4 ratio. Recurrence was defined as cytology/pathology-proven disease or morphological evidence of lesions on imaging examinations within 5 years after surgery. Radiomics features were extracted from manually segmented tumor on CT images and were then selected using four different feature selection methods sequentially. Multivariate logistic regression analysis was conducted to identify clinical features associated with recurrence. Radiomics, clinical, and combined models were constructed separately using logistic regression (LR), support vector machine (SVM), k-nearest neighbor (KNN), and neural network (NN), respectively. Receiver operating characteristic analysis was performed to evaluate the model performance in predicting recurrence. A nomogram was established based on all relevant features, with its reliability and reproducibility verified using calibration curves and decision curve analysis (DCA).

RESULTS

Eighty-nine patients with PTC experienced recurrence. A total of 1218 radiomics features were extracted from each segmentation. Five radiomics and six clinical features were related to recurrence. Among the 4 radiomics models, the LR-based and SVM-based radiomics models outperformed the NN-based radiomics model (P = 0.032 and 0.026, respectively). Among the 4 clinical models, only the difference between the area under the curve (AUC) of the LR-based and NN-based clinical model was statistically significant (P = 0.035). The combined models had higher AUCs than the corresponding radiomics and clinical models based on the same classifier, although most differences were not statistically significant. In the validation cohort, the combined models based on the LR, SVM, KNN, and NN classifiers had AUCs of 0.746, 0.754, 0.669, and 0.711, respectively. However, the AUCs of these combined models had no significant differences (all P > 0.05). Calibration curves and DCA indicated that the nomogram have potential clinical utility.

CONCLUSIONS

The combined model may have potential for better prediction of PTC recurrence than radiomics and clinical models alone. Further testing with larger cohort may help reach statistical significance.

Investigation of the Importance of Applying Various Methods of Calculation in Determining the Blood-Absorbed Dose for Patients with Differentiated Thyroid Carcinoma

The objective was to compare estimated total blood-absorbed doses obtained by applying 4 methods to the same group of patients. In addition, these results were compared with those for the patients of other researchers, who used various other techniques over a period of more than 20 y. Methods: Twenty-seven patients (22 women and 5 men) with differentiated thyroid carcinoma were enrolled in the study. Whole-body measurements were performed as conjugate-view (anterior and posterior) counts by scintillation camera imaging. All patients received 3.7 GBq of 131I for thyroid ablation. Results: The mean total blood-absorbed doses by the first, second, third, and fourth methods in the 27 patients were estimated to be 0.46 ± 0.12, 0.45 ± 0.13, 0.46 ± 0.19, and 0.62 ± 0.23 Gy, respectively. The maximum values were 1.40, 0.81, 1.04. and 1.33 Gy, respectively. The difference between the mean values was 37.22%. In the comparison with the total blood-absorbed doses for the patients of other researchers, the difference was 50.77% (difference between the means of 0.65 and 0.32 Gy). Conclusion: None of the total absorbed doses to the blood by the 4 methods in my 27 patients was 2 Gy, the maximum permissible dose. The difference between the total absorbed doses to the blood obtained by different teams of researchers was 50.77%, whereas the difference between the values by the 4 different methods in the 27 patients was 37.22%.

Should multifocality be an indication for prophylactic central neck dissection in papillary thyroid cancer?

Although multifocality is common in patients with papillary thyroid cancer, its effects on lymphatic metastasis and the necessity of central dissection in the presence of multifocality are still controversial. In our clinic, 258 patients who underwent thyroidectomy between 2015 and 2020 and were found to have papillary thyroid cancer in postoperative pathology reports were analyzed. The tumor characteristics contributing to central lymph node metastasis positivity were evaluated. Lymph node metastases were not significantly increased in the presence of multifocality. In cases with bilateral multifocal tumors, compared to cases with unilateral multifocal tumors, capsular invasion (p = 0.02), vascular invasion (p = 0.01) and cervical lymphatic metastasis (p = 0.004) were observed to increase. Bilateral multifocal tumors have more aggressive clinicopathological features than unilateral tumors. We found that the risk of central lymph node metastasis increased significantly in bilateral multifocal tumors in our study. Prophylactic central lymph node dissection may be considered in patients with no preoperative or intraoperative lymph node metastasis but thought to have a multifocal tumor.

Prognostic factors for recurrence in patients with papillary thyroid carcinoma

BACKGROUND

The prognostic factors for tumor recurrence and mortality of patients diagnosed with Papillary Thyroid Carcinoma (PTC) with immediate surgery in Colombia has not been reported.

OBJECTIVE

To retrospectively evaluate the risk factors for recurrence and survival at 10 years in patients with the diagnosis of PTC treated at Fundación Santa Fe deBogota (FSFB).

METHODS

A total of 486 patients with thyroid surgery accompanied by medical follow-up were recruited. Demographic, clinical, and pathological variables were followed-up for a median period of 10 years.

RESULTS

The most significant variables for recurrence were tumors with > 4 cm of size (hazard ratio [HR] = 8.1; 95% confidence interval [CI] = 1.7-55) and extrathyroidal spread (HR = 26.7; 95% CI = 3.1-228).

CONCLUSION

PTC in our population has low rates of mortality (0.6%) and recurrence (9.6%), with an average time of recurrence of 3 years. Size of the lesion, positive surgical margins, extrathyroidal spread, and high postoperative serum thyroglobulin (Tg) level act as prognostic factors that determine the likelihood of recurrence. Unlike other studies, the influence of age and gender does not act as a prognostic factor.

Lobo-isthmectomy in the management of differentiated thyroid cancer

We have recently witnessed a rapid increase in the incidence of differentiated thyroid carcinoma (DTC), particularly low and very low-risk papillary thyroid carcinoma. Simultaneously, the number of cancer-related deaths has remained stable for more than 30 years. Such an indolent nature and long-term survival prompted researchers and experts to an ongoing discussion on the adequacy of DTC management to avoid, on the one hand, the overtreatment of low-risk cases and, on the other hand, the undertreatment of highly aggressive ones.The most recent guidelines of the American Thyroid Association (ATA GL) moved primary thyroid surgery in DTC towards a less aggressive approach by making lobectomy an option for patients with intrathyroidal low-risk DTC tumors up to 4 cm in diameter without evidence of extrathyroidal extension or lymph node metastases. It was one of the key changes in DTC management proposed by the ATA in 2015.Following the introduction of the 2015 ATA GL, the role of thyroid lobectomy in DTC management has slowly become increasingly important. The data coming from analyses of the large databases and retrospective studies prove that a less extensive surgical approach, even if in some reports it was related to a slight increase of the risk of recurrence, did not show a negative impact on disease-specific and overall survival in T1T2N0M0 low-risk DTC. There is no doubt that making thyroid lobectomy an option for low-risk papillary and follicular carcinomas was an essential step toward the de-escalation of treatment in thyroid carcinoma.This review summarizes the current recommendations and evidence-based data supporting the necessity of de-escalation of primary thyroid surgery in low-risk DTC. It also discusses the controversies raised by introducing new ATA guidelines and tries to resolve some open questions.

Comparison of surgical strategies in the treatment of low-risk differentiated thyroid cancer

CONTEXT

Increasing diagnostic sensitivity in the detection of thyroid cancer has led to uncertainties in the optimal surgical approach of the smaller, low risk tumors. Current ATA guidelines consider lobectomy safe between 1 and 4 cm, while ETA advocates for primary total thyroidectomy to avoid reoperation, as final risk stratification is based on the histological results.

OBJECTIVE

Our aim was to compare the differences in outcomes that are potentially achievable with adherence to the different guidelines, and also to examine the predictive value of clinical parameters on the incidence of postoperative risk factors.

METHODS

We performed a retrospective cohort database analysis to identify the different surgical outcomes (based on postoperative risk factors) using ATA and ETA guidelines; the hypothetical rate of completion thyroidectomy when ATA or ETA recommends lobectomy; the accuracy of our preoperative evaluation; the utility of preoperative findings in predicting the optimal surgical strategy using binary logistic regression.

RESULTS

Out of 248 patients, 152 (ATA) and 23 (ETA) cases would have been recommended for initial lobectomy. Following the guidelines, a postoperative risk factor would have been present in 61.8, and 65.2% of the cases, respectively. Except for angioinvasion, tumor size was not a significant predictor for the presence of postoperative risk factors.

CONCLUSION

Current pre-operative criteria are inadequate to accurately determine the extent of initial surgery and our postoperative findings verify the frequent need for completion thyroidectomy using both guidelines. As a consequence, in the absence of effective pre-operative set of criteria, we advocate primary total thyroidectomy in most cases.

Prevalence of Subclinical Papillary Thyroid Cancer by Age: Meta-analysis of Autopsy Studies

CONTEXT

It is not known how underlying subclinical papillary thyroid cancer (PTC) differs by age. This meta-analysis of autopsy studies investigates how subclinical PTC prevalence changes over the lifetime.

METHODS

We searched PubMed, Embase, and Web of Science databases from inception to May 2021 for studies that reported the prevalence of PTC found at autopsy. Two investigators extracted the number of subclinical PTCs detected in selected age groups and extent of examination. A quality assessment tool was used to assess bias. Logistic regression models with random intercepts were used to pool the age-specific subclinical PTC prevalence estimates.

RESULTS

Of 1773 studies screened, 16 studies with age-specific data met the inclusion criteria (n = 6286 autopsies). The pooled subclinical PTC prevalence was 12.9% (95% CI 7.8-16.8) in whole gland and 4.6% (2.5- 6.6) in partial gland examination. Age-specific prevalence estimates were ≤40 years, 11.5% (6.8-16.1); 41-60 years, 12.1% (7.6-16.5); 61-80 years, 12.7% (8-17.5); and 81+ years, 13.4% (7.9-18.9). Sex did not affect age-specific prevalence and there was no difference in prevalence between men and women in any age group. In the regression model, the OR of prevalence increasing by age group was 1.06 (0.92-1.2, P = .37).

CONCLUSION

This meta-analysis shows the prevalence of subclinical PTC is stable across the lifespan. There is not a higher subclinical PTC prevalence in middle age, in contrast to higher observed incidence rates in this age group. These findings offer unique insights into the prevalence of subclinical PTC and its relationship to age.

Behaviour and epidemiology of differentiated thyroid cancer among filipinos in and outside the Philippines: Comparison between Qatar, Canada and Philippines

Background

No study assessed the behaviour/epidemiology of differentiated thyroid cancer (DTC) among Filipinos in the Middle East/north Africa; or compared such behaviour with Filipino DTC patients in and outside the Philippines.

Materials and methods

Retrospective review of all adult Filipinos with DTC diagnosed between 2015 and 2020 at our institution [papillary TC (PTC, n = 110); follicular TC (FTC, n = 4)]. Chi-square or t-test compared the frequency, demography, history, ultrasound, laboratory and histopathology of PTC vs FTC; and compared the epidemiology of DTC among Filipinos in Qatar vs Canada (1 study) vs the Philippines (3 studies).

Results

DTC frequency was ≈43.84 cases/100,000 Filipinos in Qatar. Males had more aggressive disease in terms of lymphovascular invasion, number of nodules, stage IV disease and metastases. PTC and FTC were similar, but more PTC patients presented with solid tumors and higher number of involved lymph nodes. DTC behaviour among Filipinos in Qatar vs Canada was fairly homogenous. Conversely, DTC among Filipinos in Qatar vs Philippines exhibited many dissimilarities: Qatar had significantly younger patients, less hyperthyroid/thyrotoxicity symptoms and neck swelling at presentation, fewer solid nodules, micro-calcifications, and multi-nodular disease; smaller tumors; more stage I and less stage IV disease; and no distant metastasis (P 0.01 to < 0.0001).

Conclusions

DTC epidemiology among Filipinos in Qatar and Canada was fairly homogenous. Conversely, DTC in Qatar vs the Philippines was dissimilar. DTC among Filipinos in Qatar has presentations that could be misinterpreted as non-suspicious. This warrants additional practices for earlier detection among Filipinos.

SPTBN2 Promotes the Progression of Thyroid Cancer by Accelerating G1/S Transition and Inhibiting Apoptosis

Background. Thyroid carcinoma (TC) is an increasingly common malignancy of endocrine organs, and its most frequently encountered histotype is papillary thyroid cancer (PTC). Identifying new potential gene alterations is important for completely elucidating the mechanism of PTC initiation and progression. Thus, we performed whole transcriptome sequence analysis (RNA-seq) on 79 PTC tissue samples and paired adjacent nontumor tissue samples to study the molecular mechanism of TC tumorigenesis and progression further. The results of RNA-seq analysis showed that spectrin beta, nonerythrocytic 2 (SPTBN2), was markedly overexpressed in PTC tissues relative to that in the paired nontumor tissues. Additionally, the analysis results for 502 PTC samples and 58 nontumor thyroid samples from The Cancer Genome Atlas dataset were consistent with our RNA-seq results. However, the molecular mechanisms and function of SPTBN2 in TC progression remain unknown. Methods. We examined SPTBN2 gene expression in 48 papillary thyroid tumor tissues and paired adjacent normal thyroid tissues by using qRT-PCR. SPTBN2 expression in the TC cell lines was silenced by small interfering RNA. Then, the transfected TC cells were used to investigate the in vitro function of SPTBN2. Result. The expression of SPTBN2 was significantly upregulated in our RNA-seq cohort, our local validated cohort, and TCGA RNA-seq cohort. The results of the in vitro experiment revealed that in TC cell lines, SPTBN2 downregulation considerably suppressed tumor cell proliferation, the cell cycle, migration, colony formation, and invasion and induced cell apoptosis. Furthermore, the protein levels of CCNE2, CDK2, CDK4, and Bcl-2 were downregulated, and those of P21, Bax, cleaved caspase-8, and cleaved caspase-3 had increased in transfected TC cells relative to in control TC cells. Conclusion. The downregulation of SPTBN2 caused apoptosis and retarded G1/S cell cycle transition in TC cells. Thus, SPTBN2 may be a good candidate gene for TC diagnosis and therapy.

Radioiodine remnant ablation in stage I adult papillary thyroid carcinoma: does it improve postoperative outcome?

Objective

To determine whether radioiodine remnant ablation (RRA) reduces cause-specific mortality (CSM) or tumor recurrence rates (TRR) after potentially curative bilateral thyroidectomy (BT) in low-risk adult papillary thyroid carcinoma (APTC) patients, we compared postoperative outcomes in 1836 pTNM stage I APTC patients having BT alone with 832 having BT+RRA during two consecutive 25-year periods.

Methods

The THEN cohort (consecutively managed during 1966-1990) comprised 809 patients (36% having BT+RRA) and the NOW cohort (1991-2015) comprised 1859 patients (29% BT+RRA). Analyses of differences in occurrence rates between BT alone and BT+RRA patients were performed with SAS software.

Results

During 1966-1990, when RRA rates rose ten-fold, 20-year CSM after BT alone was 0.6% and after BT+RRA was 1.2% (P = 0.66); during 1991-2015, when RRA rates progressively fell, no PTC deaths occurred in 1859 patients. In the THEN cohort, RRA did not significantly improve TRR at local, regional, or distant sites (P > 0.1), when compared to BT alone. RRA in NOW cohort was administered to 49% of node-positive (pN1) patients and 17% of node-negative (pN0/NX) patients (P < 0.0001); TRR therefore, were examined separately for pN0/NX and pN1 patients. In 1157 pN0/NX cases, 20-year locoregional TRR were 3.1% after BT and were higher (P = 0.049) at 8.6% after BT+RRA. In four pN1 groups, stratified by metastatic nodal burden, RRA did not significantly reduce the locoregional TRR observed after BT with curative intent (P > 0.5).

Conclusions

In a 5-decade experience, RRA administered postoperatively to stage I APTC patients did not reduce either CSM or TRR and should probably not be indicated when such patients undergo potentially curative BT.

Frequency of TERT Promoter Mutations in Real-World Analysis of 2,092 Thyroid Carcinoma Patients

BACKGRUOUND

Telomerase reverse transcriptase (TERT) promoter mutations are associated with increased recurrence and mortality in patients with thyroid carcinoma. Previous studies on TERT promoter mutations were retrospectively conducted on a limited number of patients.

METHODS

We prospectively collected data on all consecutive patients who underwent thyroid carcinoma surgery between January 2019 and December 2020 at the Samsung Medical Center, Seoul, Korea. We included 2,092 patients with thyroid carcinoma.

RESULTS

Of 2,092 patients, 72 patients (3.4%) had TERT promoter mutations. However, the frequency of TERT promoter mutations was 0.5% in papillary thyroid microcarcinoma (PTMC) ≤1 cm and it was 5.8% in papillary thyroid carcinoma (PTC) >1 cm. The frequency of TERT promoter mutations was significantly associated with older age at diagnosis (odds ratio [OR], 1.12; P<0.001), larger primary tumor size (OR, 2.02; P<0.001), and aggressive histological type (OR, 7.78 in follicular thyroid carcinoma; OR, 10.33 in poorly differentiated thyroid carcinoma; OR, 45.92 in anaplastic thyroid carcinoma; P<0.001). Advanced T stage, advanced N stage, and distant metastasis at diagnosis were highly prevalent in mutated thyroid cancers. However, initial distant metastasis was not present in patients with TERT promoter mutations in PTMC. Although the C228T mutation was more highly detected than the C250T mutation (64 cases vs. 7 cases), there were no significant clinicopathological differences.

CONCLUSION

This study is the first attempt to investigate the frequency of TERT promoter mutations in a real-world setting. The frequency of TERT promoter mutations in PTC was lower than expected, and in PTMC, young patients, and female patients, the frequency was very low.

Scoring system and a simple nomogram for predicting radioiodine refractory differentiated thyroid cancer: a retrospective study

Background

Differentiated thyroid carcinoma (DTC) originates from abnormal follicular cells and accounts for approximately 90–95% of thyroid malignancies. The diagnosis of radioiodine refractory DTC (RR-DTC) is based on clinical evolution and iodine uptake characteristics rather than pathological characteristics. Thus, it takes a long time to become apparent, and the definition of RR-DTC covers multiple aspects. We aimed to analyze the clinical and molecular imaging characteristics of patients with RR-DTC and identify independent predictors to develop an RR-DTC scoring system and a simple nomogram for predicting the probability of RR-DTC. We reviewed the data of 404 patients with metastatic DTC who underwent both post-RAI WB therapy scintigraphy and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography. Data on the clinical features and molecular characteristics of RR-DTC and non-RR-DTC cases were obtained from medical records. We screened for predictors using univariate analyses, obtained independent predictors through multivariate analyses, and then established a scoring system and a simple nomogram for predicting RR-DTC according to the corresponding odds ratio (OR) values.

Results

Diagnosis at age ≥ 48 years (OR, 1.037; 95% confidence interval [CI], 1.007–1.069), recurrence between the operation and iodine-131 treatment (OR, 7.362; 95% CI 2.388–22.698), uptake of ¹⁸F-FDG (OR, 39.534; 95% CI 18.590–84.076), and the metastasis site (OR, 4.365; 95% CI 1.593–11.965) were highly independently associated with RR-DTC. We established a scoring system for predicting RR-DTC, showing that the area under the receiver operating characteristic curve (AUC) with a cutoff value of 10 points (AUC = 0.898) had a higher discernibility than any other single independent predictor. The risk factors of RR-DTC in nomogram modeling include diagnosis at age ≥ 48 years, recurrence between the operation and iodine-131 treatment, uptake of ¹⁸F-FDG, and the site of metastasis. The concordance index (c-Index) of the nomogram was 0.9.

Conclusions

We demonstrated that a predictive model based on four factors has a good ability to predict RR-DTC. An index score ≥ 10 points was found to be the optimal index point for predicting RR-DTC. Moreover, this nomogram model has good predictive ability and stability. This model may help establish an active surveillance or appropriate treatment strategy for RR-DTC cases.

circSSU72 Promotes Cell Proliferation, Migration and Invasion of Papillary Thyroid Carcinoma Cells by Targeting miR-451a/S1PR2 Axis

Introduction: Thyroid cancer is the most common endocrine malignancy with Papillary Thyroid Carcinoma (PTC) as the most common pathological type. Due to low mortality but a high incidence, PTC still causes a relatively heavy burden on financial costs, human health, and quality of life. Emerging researches have indicated that circular RNAs (circRNAs) play a significant regulatory role in various cancers, including PTC. However, the functions and mechanisms of circRNAs derived from SSU72 remain unknown.

Method: The expression level of circRNAs derived from the exons of SSU72, miR-361–3p, miR-451a, and S1PR2 was evaluated by qRT-PCR assay or western blot assay. The interactions between circSSU72 (hsa_circ_0009294), miR-451a, and S1PR2 were verified by dual-luciferase reporter assay. Effects of circSSU72, miR-451a, and S1PR2 on cell proliferation, migration, and invasion were confirmed by colony formation assay, cell counting kit-8 (CCK-8), wound healing assay, and Transwell assays in vitro.

Results: circSSU72 was upregulated in PTC; circSSU72 knockdown inhibited PTC cell proliferation, migration, and invasion. In addition, circSSU72 could negatively regulate miR-451a by functioning as a sponge. circSSU72 promoted PTC cell proliferation, migration, and invasion by targeting miR-451a in vitro. We further found that miR-451a inhibited PTC cell proliferation, migration, and invasion by regulating S1PR2. Overall, the circSSU72/miR-451a/S1PR2 axis might influence PTC cell proliferation, migration, and invasion.

Conclusions: Overall, circSSU72 (hsa_circ_0009294)/miR-451a/S1PR2 axis may promote cell proliferation, migration, and invasion in PTC. Thus, circSSU72 may serve as a potential biomarker and therapeutic target for PTC.

Comparison between 2015 ATA guidelines and Italian Consensus for DTC management. A commented report

The 2015 ATA guidelines and 2018 Italian Consensus have produced a series of generally concordant recommendations on clinical and therapeutic management of thyroid nodules and thyroid carcinoma. Currently, the goals of treatment are to achieve the highest disease-free survival rates through the best ratio between minimum invasiveness and cost/impact on quality of life. By analysis and comparison of the ATA Guidelines and Italian Consensus, we highlighted and commented upon the key points of differentiated thyroid cancer management. Furthermore, the aim of this work is to identify and promote uniform clinical approaches among all specialists who treat differentiated thyroid cancer and represent a starting point for a consensus drafted by the Italian Society of Otolaryngology - Head and Neck Surgery.

Comparison between Two Different Scanners for the Evaluation of the Role of 18F-FDG PET/CT Semiquantitative Parameters and Radiomics Features in the Prediction of Final Diagnosis of Thyroid Incidentalomas

The aim of this study was to compare two different tomographs for the evaluation of the role of semiquantitative PET/CT parameters and radiomics features (RF) in the prediction of thyroid incidentalomas (TIs) at ¹⁸F-FDG imaging. A total of 221 patients with the presence of TIs were retrospectively included. After volumetric segmentation of each TI, semiquantitative parameters and RF were extracted. All of the features were tested for significant differences between the two PET scanners. The performances of all of the features in predicting the nature of TIs were analyzed by testing three classes of final logistic regression predictive models, one for each tomograph and one with both scanners together. Some RF resulted significantly different between the two scanners. PET/CT semiquantitative parameters were not able to predict the final diagnosis of TIs while GLCM-related RF (in particular GLCM entropy_log2 e GLCM entropy_log10) together with some GLRLM-related and GLZLM-related features presented the best predictive performances. In particular, GLCM entropy_log2, GLCM entropy_log10, GLZLM SZHGE, GLRLM HGRE and GLRLM HGZE resulted the RF with best performances. Our study enabled the selection of some RF able to predict the final nature of TIs discovered at ¹⁸F-FDG PET/CT imaging. Classic semiquantitative and volumetric PET/CT parameters did not reveal these abilities. Furthermore, a good overlap in the extraction of RF between the two scanners was underlined.

Efficacy of radiofrequency ablation for metastatic papillary thyroid cancer with and without initial biochemical complete status

OBJECTIVE

The application of radiofrequency ablation (RFA) for recurrent thyroid cancer has been demonstrated to effectively manage lesions at critical locations, such as abutting the trachea, with limited complications. Comprehensive investigation of both biochemical (B) and structural (S) change after RFA remains limited. We herein present the first single-center experience of RFA for the treatment of locoregional recurrent thyroid cancer in Taiwan.

DESIGN

23 patients were enrolled, and the treatment responses after RFA were divided into four groups (E, S(+), B(+), and SB(+)), and then compared. The RFA technique, follow-up strategy, changes in pre-and post-operative status, and complications are presented. The volume reduction rate at 1, 3, and 6 months, and the differing responses between lesions abutting/not abutting the trachea are also discussed.

RESULTS

In patients with pre-RFA structural and biochemical incomplete (SB(+)) status, presenting with lesion with an initial maximum diameter of >3.2cm, a higher rate of structural incomplete status at the 6-month follow-up was noted in ROC analysis, with a sensitivity of 57% and specificity of 91%. Favorable structural remission after RFA was noted, and 60.9% of patients achieved biochemical complete status. No significant correlation was noted between the trachea-abutted lesion number and complete remission (p= 0.474). No significant difference in RFA efficacy was noted between the lesions abutting/not abutting the trachea.

CONCLUSIONS

This retrospective study reveals that RFA can achieve both structural and biochemical improvements for locoregionally recurrent thyroid cancer, with a low complication rate. Nearly half of the patients achieved an excellent response after RFA, while a favorable treatment response can be achieved despite the lesion abutting the trachea, with a mean VRR of 84.74%.

Radioiodine adjuvant therapy in differentiated thyroid cancer: An update and reconsideration

Radioiodine (¹³¹I) therapy (RAI) has been utilized for treating differentiated thyroid cancer (DTC) for decades, and its uses can be characterized as remnant ablation, adjuvant therapy (RAT) or treatment for known diseases. Compared with the definite ¹³¹I treatment targets for remnant ablation and known disease, ¹³¹I adjuvant therapy (RAT) aims to reduce the risk of recurrence by destroying potential subclinical disease. Since it is merely given as a risk with no imaging confirmation of persistence/recurrence/metastases, the evidence is uncertain. With limited knowledge and substance, the indication for RAT remains poorly defined for everyday clinical practice, and the benefits of RAT remain controversial. This ambiguity results in a puzzle for clinicians seeking clarity on whether patients should receive RAT, and whether patients are at risk of recurrence/death from undertreatment or adverse events from overtreatment. Herein, we clarified the RAT indications in terms of clinicopathological features, postoperative disease status and response to therapy evaluation, and retrospectively examined the clinical outcomes of RAT as reported in current studies and guidelines. Furthermore, given the evolution of nuclear medicine imaging techniques, it can be expected that the future of RAT may be advanced by nuclear medicine theranostics (i.e., ¹³¹I whole-body scan, PET/CT) by accurately revealing the biological behaviors, as well as the underlying molecular background.

Radioiodine therapy in patient of differentiated thyroid cancer with end-stage renal disease on maintenance hemodialysis: case report with review of literature

Surgical resection followed by radioactive-iodine (¹³¹I) therapy constitutes a standard treatment for differentiated thyroid cancer (DTC). ¹³¹I is normally excreted through kidneys and treatment of patients with end stage renal disease (ESRD) on hemodialysis requires special attention for dosage of ¹³¹I, timing of dialysis and radiation safety. We present a case of a post-thyroidectomy patient with ESRD on haemodialysis who required radioactive iodine ablation with review of literature.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

KEY POINTS

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

Imaging of Cervical Lymph Nodes in Thyroid Cancer: Ultrasound and Computed Tomography

Sonographic evaluation of cervical lymph nodes in patients with thyroid malignancy is important both for preoperative staging and for post-treatment surveillance, and contrast-enhanced computed tomography plays a complementary role. Knowledge of anatomy and surgical approaches, combined with an understanding of the various imaging features that distinguish malignant from benign lymph nodes, allows for accurate staging, thereby enabling complete surgical initial resection.

Inability of Radioiodine Remnant Ablation to Improve Postoperative Outcome in Adult Patients with Low-Risk Papillary Thyroid Carcinoma

OBJECTIVE

To determine whether radioiodine remnant ablation (RRA) reduces cause-specific mortality (CSM) or tumor recurrence (TR) rate after bilateral lobar resection (BLR).

PATIENTS AND METHODS

There were 2952 low-risk adult papillary thyroid cancer (LRAPTC) patients (with MACIS scores <6) who underwent potentially curative BLR during 1955-2014. During 1955-1974, 1975-1994, and 1995-2014, RRA was administered in 3%, 49%, and 28%. Statistical analyses were performed using SAS software.

RESULTS

During 1955-1974, the 20-year CSM and TR rates after BLR alone were 1.0% and 6.8%; rates after BLR+RRA were 0% (P=.63) and 5.9% (P=.82). During 1975-1994, post-BLR 20-year rates for CSM and TR were 0.3% and 7.5%; after BLR+RRA, rates were higher at 0.9% (P=.31) and 12.8% (P=.01). When TR rates were examined separately for 448 node-negative and 317 node-positive patients, differences were nonsignificant. In 1995-2014, post-BLR 20-year CSM and TR rates were 0% and 9.2%; rates after BLR+RRA were higher at 1.4% (P=.19) and 21.0% (P<.001). In 890 pN0 cases, 15-year locoregional recurrence rates were 3.4% after BLR and 3.7% after BLR+RRA (P=.99). In 740 pN1 patients, 15-year locoregional recurrence rates were 10% higher after BLR+RRA compared with BLR alone (P=.01). However, this difference became nonsignificant when stratified by numbers of metastatic nodes.

CONCLUSION

RRA administered to LRAPTC patients during 1955-2014 did not reduce either the CSM or TR rate. We would therefore not recommend RRA in LRAPTC patients undergoing BLR with curative intent.

Quality of life comparison in thyroxine hormone withdrawal versus triiodothyronine supplementation prior to radioiodine ablation in differentiated thyroid carcinoma: a prospective cohort study in the Indian population

BACKGROUND

Thyroid withdrawal in preparation for radioiodine ablation (RIA) may have a profound impact on health-related quality of life (HRQL). Cost implications and scheduling limit the use of recombinant TSH and triiodothyronine (T3) with its shorter half-life is a conceptually attractive alternative.

METHODS

Prospective cohort study design with patients having withdrawal of thyroxine (n = 37) or T3 supplementation (n = 33). HRQL was assessed using EORTC QLQ-C30, QLQ-H&N35 and modified Billewicz questionnaires. Time interval to achieve optimal TSH levels (at least 30 mIU/ml) prior to RIA was determined.

RESULTS

With the exception of emotional domain (QLQ-C30 p = 0.045), LT3 supplementation did not confer significant benefit when compared to LT4 withdrawal. Target serum TSH levels was achieved in 95% of patients by week 4 post thyroidectomy.

CONCLUSIONS

LT3 supplementation delivered equivocal benefit and therefore the alternate strategies to minimize the impact on HRQL of reduction in the duration of hypothyroidism in T4 withdrawal are suggested.

Prognostic Assessment of BRAF Mutation in Preoperative Thyroid Fine-Needle Aspiration Specimens

OBJECTIVES

We investigate the potential role of BRAF testing in guiding surgical intervention in papillary thyroid carcinoma (PTC).

METHODS

Thyroid fine-needle aspiration (FNA) cases with available BRAF result and follow-up thyroidectomy for PTC were included in the study. Cytology and surgical diagnoses were correlated with BRAF status.

RESULTS

There were 151 cases of thyroid FNA specimens with BRAF testing (70 mutant and 81 wild-type BRAF) and histologically confirmed unilateral, unifocal PTCs. There were no differences in age, sex, tumor size, or lymphovascular invasion on thyroidectomy specimens between mutant and wild-type BRAF cases. BRAF mutation was significantly associated with cytology diagnosis (P < .001), PTC subtype (P < .001), extrathyroidal extension (ETE) (P = .006), and higher tumor (T) stage (P = .04). However, an analysis within the histologic subtypes of PTC revealed no significant association between BRAF mutation and ETE or higher T stage. There was also no difference in central (P = .847) or lateral (p = 1) neck lymph node (LN) metastasis.

CONCLUSIONS

BRAF mutation identified in thyroid FNA specimens correlates with histologic subtypes but is not an independent factor for predicting PTC biological behavior and should not be used to guide the extent of LN dissection.

Trends in Thyroid Surgery and Guideline-Concordant Care in the United States, 2007-2018

Background: The American Thyroid Association (ATA) published the 2015 Management Guidelines for patients with thyroid nodules and differentiated thyroid cancer, recommending a shift to less aggressive diagnostic, surgical, and postoperative treatment strategies. At the same time and perhaps related to the new guidelines, there has been a shift to outpatient thyroid surgery. The aim of the current study was to assess physician adherence to these recommendations by identifying and quantifying temporal trends in the rates and indications for thyroid procedures in the inpatient and outpatient settings. Methods: Using the IBM^® MarketScan^® Commercial database, we identified employer-insured patients in the United States who underwent outpatient and inpatient thyroid surgery from 2007 to 2018. Thyroid surgery was classified as total thyroidectomy (TT), thyroid lobectomy (TL), or a completion thyroidectomy. The surgical indication diagnosis was also determined and classified as either benign or malignant thyroid disease. We compared outpatient and inpatient trends in surgery between benign and malignant thyroid disease both before and after the release of the 2015 ATA guidelines. Results: A total of 220,088 patients who underwent thyroid surgery were included in the analysis. Approximately 80% of TLs were performed in the outpatient setting versus 70% of TTs. Longitudinal analysis showed a statistically significant changepoint for TT proportion occurring in November 2015. The proportion of TT as compared with TL decreased from 80% in September 2015 to 39% by December 2018. For thyroid cancer, there is an increasing trend in performing TL over TT, increasing from 17% in 2015 to 28% by the end of 2018. Conclusions: There was a significant changepoint occurring in November 2015 in the operative and management trends for benign and malignant thyroid disease.

Therapeutic Strategy in Low-Risk Papillary Thyroid Carcinoma - Long-Term Results of the First Single-Center Prospective Non-Randomized Trial Between 2011 and 2015

Optimal therapeutic strategy in low advanced papillary thyroid carcinoma (PTC) is still a matter of debate. The management differs depending on the country. A prospective non-randomized study was performed to evaluate whether less extensive surgery could be a safe, acceptable, and sufficient therapeutic option in PTC cT1N0M0 patients. The present paper summarizes the results of over a 5-year follow-up.

MATERIAL

Our prospective group (PG) treated between 2011 and 2015 consisted of 139 patients with cT1aN0M0 PTC who underwent lobectomy (LT) as initial surgical treatment (PGcT1aN0M0 group) and 102 cT1bN0M0 patients in whom total thyroidectomy (TT) with unilateral central neck dissection (CND) was performed (PGcT1bN0M0). PG was compared with the retrospective group (RG) of patients who underwent TT with bilateral CND between 2004 and 2006: 103 cT1aN0M0 patients (RGcT1aN0M0) and 91cT1bN0M0 (RGcT1bN0M0). The risks of reoperation, cancer relapse and postoperative complications were analyzed.

RESULTS

Only 12 cT1aN0M0 patients (7.6%) withdrew from the trial and underwent TT with bilateral CND. Over 90% of patients accepted less extensive surgery. In 4 cT1aN0M0 cases, TT with CND was performed due to lymph node metastases found intraoperatively. The initial clinical stage according to the TNM/AJCC 7^th edition was confirmed histologically in 77% of cases in PGT1aN0M0 and in 72% in PGT1bN0M0, respectively. 24 PGcT1aN0M0 patients were reoperated on. In this group, cancer lesions in the postoperative histological specimens were found in 8 cases (32%). Five-year disease-free survival (DFS) was excellent. However, no statistically significant differences were found between PG and RG groups (99.3% in PGcT1aN0M0 and 99.0%, in RGcT1aN0M0; p = 0.41 and 98%, in PGcT1bN0M0 and 94.4% in RGcT1bN0M0; p=0.19). No significant differences were observed in the incidence of early paresis of the recurrent laryngeal nerves between PG and RG. However, as predicted, LT completely eliminated the risk of postoperative hypoparathyroidism.

SUMMARY

The results of the prospective clinical trial confirm that less extensive surgery in adequately selected low-advanced PTC patients is both safe and sufficient.

Long-term follow-up of differentiated thyroid carcinoma in children and adolescents

Objectives The aims were to analyze the clinical features, response to treatment, prognostic factors and long-term follow-up of children and adolescents with differentiated thyroid carcinoma (DTC). Methods Eighty patients with DTC were studied retrospectively. All underwent total or near-total thyroidectomy, and in 75 cases, ablative iodine therapy was recommended. Patients were assessed periodically by tests for serum thyroglobulin levels and whole-body iodine scans. Age, gender, initial clinical presentation, histology, tumor stage, postoperative complications, radioiodine treatment protocol, treatment response, thyroglobulin (Tg), recurrence and long-term disease progression were evaluated. Results Seventy patients completed >2 years of follow-up (23 males, 47 females; median age: 14 years; range: 3-18 years). Sixty-two patients showed papillary DTC and eight, follicular DTC. Sixty-five percent presented nodal metastasis and 16%, pulmonary metastasis at diagnosis. Six months after first radioiodine treatment, 36.2% of patients were free of disease. Seven recurrences were documented. At the end of follow-up, overall survival was 100%, and 87.2% of patients were in complete remission. Nine patients had persistent disease. We found a significant association between stage 4 and persistent disease. Hundred percent of patients with negative Tg values at 6 months posttreatment were documented free of disease at the end of the follow-up. The analysis of disease-free survival based on radioiodine treatment protocols used showed no statistically significant differences. Conclusions DTC in children and adolescents is frequently associated with presence of advanced disease at diagnosis. Despite this, complete remission was documented after treatment in most cases, with a good prognosis in the long-term follow-up. Negative posttreatment thyroglobulin and stage 4 at diagnosis were significant prognostic variables.

The Effect of BRAF V600E Mutation on Lymph Node Involvement in Papillary Thyroid Cancer

OBJECTIVES

Papillary thyroid cancer (PTC) is the most common well-differentiated thyroid cancer. Lymph node (LN) metastasis is frequently seen in PTC. The effect of BRAFV600E mutation on PTC-associated LN metastasis has not been clearly established. Therefore, we aimed to evaluate the effect of the BRAFV600E mutation in patients with PTC on regional LN metastasis.

MATERIAL AND METHODS

Between January 2013 and 2017, sixty-three PTC patients who underwent central lymph node dissection were included into the study. The patients were divided into two groups according to the pathology results of the LN dissection, and these groups were compared for positive BRAFV600E mutations and other clinicopathological findings.

RESULTS

BRAFV600E mutation was found to be more significant in the pLN1 group (p= 0.005). Multivariate analysis revealed that nodule size, microcalcifications, and BRAFV600E mutation were associated with lymph node metastasis independent of other parameters. ROC analysis also evaluated the adequacy of the BRAFV600E mutation in predicting the presence of LN involvement. AUC: 0.738 (95%CI:0.6110.866,p: 0.002).

CONCLUSION

In our study, independent of other parameters, BRAFV600E gene mutation was found to be effective on lymph node involvement.

Prognostic factors and the effect of radioiodine on patients with locally advanced differentiated thyroid cancer

Background

Locally advanced differentiated thyroid cancer (DTC) is rare. The optimal treatment remains controversial. This study was to investigate the natural history and prognostic factors of patients with locally advanced DTC and assess the effects of radioiodine therapy for locally advanced DTC.

Methods

A retrospective study was performed in 259 patients with locally advanced DTC. The clinicopathological features, prognostic factors and the effects of radioiodine therapy were evaluated using univariate and multivariate statistical analysis.

Results

Among the clinicopathological characteristics of locally advanced DTC, the patient’s age (unfavourable >55 years), extent of primary tumour (more widely extrathyroidal extension showed a worse prognosis than others), tumor size, histopathological classifications and distant metastases were the significant prognostic factors. With regard to the effects of RAI on local invasive DTC, neither T3b nor T4 patients without distant metastases could benefit from performance of ¹³¹I therapy for over survival and locoregional relapse-free survival.

Conclusions

In patients with locally advanced DTC, the independent prognostic factors were age, extent of extrathyroidal invasion, tumor size, histopathological classifications and distant metastases. Adjuvant postoperative RAI did not affect overall survival and locoregional control in patients with locally advanced DTC who had no distant metastasis disease. Given the results, we suggested radioiodine would not be applied for metastasis-free patients with locally advanced DTC postoperatively.

The Impact of the Extent of Surgery on the Long-Term Outcomes of Patients with Low-Risk Differentiated Non-Medullary Thyroid Cancer: A Systematic Meta-Analysis

Recently, the management of patients with low-risk differentiated non-medullary thyroid cancer (DTC), including papillary and follicular thyroid carcinoma subtypes, has been critically appraised, questioning whether these patients might be overtreated without a clear clinical benefit. The American Thyroid Association (ATA) guideline suggests that thyroid lobectomy (TL) could be a safe alternative for total thyroidectomy (TT) in patients with DTC up to 4 cm limited to the thyroid, without metastases. We conducted a meta-analysis to assess the clinical outcomes in patients with low-risk DTC based on the extent of surgery. The risk ratio (RR) of recurrence rate, overall survival (OS), disease-free survival (DFS) and disease specific survival (DSS) were estimated. In total 16 studies with 175,430 patients met the inclusion criteria. Overall, low recurrence rates were observed for both TL and TT groups (7 vs. 7%, RR 1.10, 95% CI 0.61-1.96, I² = 72%), and no statistically significant differences for OS (TL 94.1 vs. TT 94.4%, RR 0.99, CI 0.99-1.00, I² = 53%), DFS (TL 87 vs. TT 91%, RR 0.96, CI 0.89-1.03, I² = 85%), and DSS (TL 97.2 vs. TT 95.4%, RR 1.01, CI 1.00-1.01, I² = 74%). The high degree of heterogeneity of the studies is a notable limitation. Conservative management and appropriate follow-up instead of bilateral surgery would be justifiable in selected patients. These findings highlight the importance of shared-decision making in the management of patients with small, low-risk DTC.

BRAF and TERT promoter mutations: clinical application in thyroid cancer

Given the long-term survival of most patients with thyroid cancer, it is very important to distinguish patients who need aggressive treatment from those who do not. Conventional clinicopathological prognostic parameters could not completely predict the final outcome of each patient. Recently, molecular marker-based risk stratification of thyroid cancer has been proposed to better estimate the cancer risk. Although BRAF mutation has drawn much attention based on its high prevalence, its association with recurrence or mortality is not clear. Recently, telomerase reverse transcriptase (TERT) promoter mutation has been identified in thyroid cancer. It increases telomerase activity, which allows cancer cells to immortalize. It was found in 10 to 20% of differentiated thyroid carcinoma and 40% of dedifferentiated thyroid carcinoma. It is highly prevalent in old age, large tumor, aggressive histology, advanced stages, and distant metastasis. It is associated with increased recurrence and mortality. Concomitant BRAF and TERT promoter mutations worsen the survival rate. Inclusion of TERT promoter mutation analysis with conventional clinicopathological evaluation can lead to better prognostication and management for individual patients.

Role of 18F-FDG-PET/CT in patients with differentiated thyroid cancer with biochemical incomplete or indeterminate response to treatment

OBJECTIVES

To assess the value of ¹⁸F-FDG-PET/CT for detecting recurrent/persistent disease in patients with biochemical incomplete (BIR) or indeterminate response (IR) and to assess the impact of ¹⁸F-FDG-PET/CT on the therapeutic management of these patients.

METHODS

The study included patients with BIR, in whom ¹⁸F-FDG PET/CT was used within the diagnostic algorithm from our database. Patients with IR referred to our hospital with the ¹⁸F-FDG PET/CT already performed were also enrolled. All patients had neck ultrasonography with no structural changes. A change in therapeutic approach was defined as repeat surgery; administration of external beam radiotherapy; and/or the start of systemic therapy.

RESULTS

Sixty patients (85% women) aged 18-86 years were enrolled in this retrospective study. Of these, 75% had BIR and 25% IR. Increased FDG uptake suggesting locoregional lesions was seen in 40% of patients. Sensitivity, specificity, and diagnostic accuracy of ¹⁸F-FDG PET/CT to detect local disease were 95%, 87.5% and 90% respectively. The therapeutic approach was modified in 50% of patients with locoregional lesions.

CONCLUSIONS

Our study confirmed that ¹⁸F-FDG-PET/CT is a useful tool for detecting locoregional recurrence in thyroid cancer patients with BIR or IR with conflicting findings in standard diagnostic procedures. In 50% of patients with locoregional lesions, there was an immediate change in the treatment approach.

Is Less More? A Microsimulation Model Comparing Cost-effectiveness of the Revised American Thyroid Association's 2015 to 2009 Guidelines for the Management of Patients With Thyroid Nodules and Differentiated Thyroid Cancer

OBJECTIVE

To assess relative clinical and economic performance of the revised American Thyroid Association (ATA) thyroid cancer guidelines compared to current standard of care.

BACKGROUND

Diagnosis of thyroid cancer in the United States has tripled whereas mortality has only marginally increased. Most patients present with small papillary carcinomas and have historically received at least a total thyroidectomy as a treatment. In 2015, the ATA released the revised guidelines recommending an option for active surveillance (AS) of small papillary thyroid carcinoma and thyroid lobectomy for larger unifocal tumors.

METHODS

We created a Markov microsimulation model to evaluate the performance of the ATA's 2015 guidelines compared to the ATA's 2009 guidelines. We modeled a cohort of simulated patients with demographic and thyroid nodule characteristics representative of those presenting clinically in the United States. Outcome measures include life expectancy, quality-adjusted life years, costs, and frequency of surgical adverse events.

RESULTS

In our base case analysis, the ATA 2015 strategy dominates the ATA 2009 strategy. The ATA 2015 strategy delivers greater discounted average quality-adjusted life years (13.09 vs 12.43) at a lower discounted average cost ($14,752 vs $20,126). Deaths due to thyroid cancer under the 2015 strategy are higher than the 2009 strategy but this is offset by a reduction in surgical deaths, leading to greater average life expectancy under the ATA 2015 strategy. The optimal strategy is sensitive to patients who experience a greater decrement in quality of life while undergoing AS.

CONCLUSIONS

The ATA 2015 Guidelines represent a cost-effective strategy regarding AS and extent of surgery.

Total thyroidectomy with therapeutic level II-IV neck dissection for papillary thyroid carcinoma: level VI recurrence patterns

OBJECTIVE

Lateral and central compartments cervical lymph nodes metastases are common among patients with papillary thyroid carcinoma (PTC). Elective level VI neck dissection during thyroidectomy and lateral neck dissection (LND) for the treatment of PTC with lateral compartment lymph node metastases is controversial because of the uncertain benefit in clinical outcomes and increased risks of surgical morbidity. We aimed to determine the potential benefit of elective level VI neck dissection in patients with cN1 papillary thyroid carcinoma (PTC) by investigating the rate and pattern of locoregional recurrence in PTC patients who underwent total thyroidectomy and therapeutic lateral node dissection (LND; levels II-IV) without elective level VI dissection.

METHODS

A retrospective cohort study. Data on demographics, clinical presentation and workup, intraoperative and pathological report, postoperative course, adjuvant therapy, recurrence patterns, and overall survival were retrieved from the medical charts of patients who underwent thyroid surgery in our hospital between January 2006 and December 2017.

RESULTS

A total of 1415 thyroidectomies were performed during the study period, of which 802 (56.67%) were for PTC. Of those PTC patients, 228 (28.42%) also underwent LND (levels II-VI) during the same thyroidectomy procedure. Thirty-four (14.91%) of those 228 patients, underwent total thyroidectomy with therapeutic lateral ND II-IV without elective level VI ND. During the follow-up period, five (14.7%) of the latter cohort were diagnosed with recurrence in central neck (level VI) lymph nodes, and four of them (11.7%) were diagnosed with ipsilateral recurrence at level VI.

CONCLUSION

Our results revealed 11.7% rate of clinically significant recurrent disease in ipsilateral level VI which, in our opinion, does not justify routine prophylactic level VI ND dissection when the ipsilateral lateral neck is operated for metastases.

Divergent Metastatic Patterns Between Subtypes of Thyroid Carcinoma Results From the Nationwide Dutch Pathology Registry

BACKGROUND

Metastatic disease is the main cause of cancer-related mortality in thyroid carcinoma (TC) patients. Clinical studies have suggested differences in metastatic patterns between the different subtypes of TC. This study systematically evaluates the metastatic patterns of different subtypes in TC patients.

METHODS

A nationwide review of pathological records of all 650 patients diagnosed with a primary malignancy in the thyroid who underwent an autopsy between 1991 and 2010 was performed. Patients were selected from the Dutch pathology registry (PALGA).

RESULTS

Metastatic disease was present in 228 (35.1%) patients and was found in 38.7%, 17.3%, 75.4%, and 47.8% of patients with follicular, papillary, anaplastic, and medullary types of TC, respectively (P < .0001). The majority of patients had more than 1 metastasis. The most common site of metastatic disease was the lung for papillary (79.7%), follicular (72.9%), and anaplastic (92.1%) carcinoma but not for medullary carcinoma (56.3%), P < .0001. Medullary carcinoma patients most frequently had metastases to the liver (81.3%). The combination of metastases also differed between subtypes.

CONCLUSION

There are major differences in metastatic patterns between different subtypes of TC. The patterns and frequencies identified in this autopsy study may reflect the underlying biology of metastatic thyroid cancer and have potential to influence future monitoring and treatment strategies depending on clinical correlations.

Determination and Comparison of Radiation Absorbed dose to the Blood, by Applying Different Techniques, for Patients, Suffering from Differentiated Thyroid Cancer

Background:

Radiation absorbed dose to the red bone marrow, in the therapy of differentiated thyroid carcinoma (DTC) with 131I (radioiodine), cannot be measured directly. The absorbed dose to the blood seems to be a good first- order approximation of the radiation absorbed dose to the hematopoietic system and a better means to quantify exposure from therapy than the total amount of activity administered.

Objective:

The aim of this research was to determine the radiation absorbed dose to the blood, for patients suffering from differentiated thyroid cancer.

Materials and Methods:

Twenty seven patients, 22 women and 5 men, suffering from DTC were enrolled in this study. We applied four formulas and we compared between the estimated values of absorbed dose that were obtained by three formulas and those that obtained by fourth (standard one).

Results:

All the values of absorbed dose that obtained by one of the techniques were regularly highly estimated, even though they have an excellent correlation (99%) with the standard value.

Conclusions:

Highly overestimated or highly underestimated results that can be obtained by certain method or technique are not desirable, because they tend to exaggerate, by increasing or decreasing, the radiation protection procedures.

Conversion radiation Units:

To convert the values of absorbed dose from S.I unit (mGy/MBq) to traditional unit (rad/mCi), we can simply multiply the values that expressed in S.I units by a factor of 3.7, and we don't need to apply complicated formulas, which were applied by other researches.

Metastatic Thyroid Cancer Presenting as Renal Cortical Mass

The authors present a rare case of primary diagnosis of metastatic, differentiated thyroid cancer presenting as a solitary, large renal mass. Renal cortical masses which represent metastatic primary malignancies are often small, multifocal, and in the setting of active malignancy. Surgical excision of this patient's renal mass demonstrated the unexpected diagnosis and subsequent endocrine surgical intervention.

Hemorheology and oxidative stress in patients with differentiated thyroid cancer following I-131 ablation/metastasis treatment

BACKGROUND

Although radioiodine theraphy (RAIT) is thought to affect blood cells and oxidative stress, hemorheological alterations following dose-dependent RAIT remains unknown.

OBJECTIVE

The aim of this study was to determine the effects of RAIT on hemorheological and oxidative stress parameters in patients with differentiated thyroid cancers (DTC).

METHODS

Totally 31 DTC patients (mean age 46.32±11.15 years) and 26 healthy controls (mean age 50.50±6.22 years) were included. Venous blood samples were collected from each patient before and after treatment (7th day, 1th month and 6th month). Erythrocyte aggregation-deformability and oxidative stress parameters were determined. p < 0.05 was considered as statistically significant.

RESULTS

Erythrocyte deformability of the patients determined at 16.87 and 30 Pascal were significantly lower than healthy individuals. Erythrocyte aggregation index (AI) of the patients was higher, whereas erythrocyte aggregation half-time (t½) was lower compared to control. Erythrocyte deformability values and AI were not significantly different from the pre- and post-radioiodine treatment groups. There was no statistically significant difference between the oxidative stress parameters before and after the treatment.

CONCLUSIONS

Patients were in a worse hemorheological condition compared to healthy individuals. After RAIT, RBC deformability and aggregation were not affected and no significant change in oxidative stress parameters was detected.

Contemporary Debates in Adult Papillary Thyroid Cancer Management

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

PROGNOSIS OF DIFFERENTIATED THYROID CARCINOMA IN PATIENTS WITH GRAVES DISEASE: A SYSTEMATIC REVIEW AND META-ANALYSIS

Objective: It is still controversial whether differentiated thyroid carcinoma (DTC) in patients with Graves disease (GD) can be more aggressive than non-Graves DTC. We conducted a systematic review and meta-analysis to examine the association between GD and prognosis in patients with DTC. Methods: We comprehensively searched the databases of MEDLINE and EMBASE from inception to March 2019. We included published studies that compared the risk of mortality and prognosis between DTC patients with GD and those with non-GD. Data from each study were combined using the random-effects model. Results: Twenty-five studies from February 1988 to May 2018 were included (987 DTC patients with GD and 2,064 non-Graves DTC patients). The DTC patients with GD had a significantly higher risk of associated multifocality/multicentricity (odds ratio, 1.45; 95% confidence interval, 1.04 to 2.02; I², 6.5%; P = .381) and distant metastasis at the time of cancer diagnosis (odds ratio, 2.19; 95% confidence interval, 1.08 to 4.47; I², 0.0%; P = .497), but this was not associated with DTC-related mortality and recurrence/persistence during follow-up. Conclusion: Our meta-analysis demonstrates a statistically significant increased risk of multifocality/multicentricity and distant metastasis at the time of cancer diagnosis in DTC patients with GD than those without GD. Abbreviations: CI = confidence interval; DTC = differentiated thyroid carcinoma; GD = Graves disease; LN = lymph node; OR = odds ratio; PTC = papillary thyroid carcinoma; TC = thyroid carcinoma; TSAb = thyroid-stimulating antibody; TSH = thyroid-stimulating hormone.

Impact of the change from the seventh to eighth edition of the AJCC TNM classification of malignant tumours and comparison with the MACIS prognostic scoring system in non-medullary thyroid cancer

Background

In 2018, AJCC TNM staging changed for differentiated (DTC) and anaplastic (ATC) thyroid carcinoma. The impact of this change on mortality rates was investigated and compared with the MACIS prognostic score.

Methods

Analysis of a prospective database of DTC/ATC was undertaken. Patients were staged according to TNM7 and TNM8 criteria, and MACIS scores calculated. Five‐year disease‐specific mortality rates were determined. Proportions were compared with Fisher's exact and χ² goodness‐of‐fit tests.

Results

Between August 2002 and December 2016, 310 patients had primary surgery for thyroid cancer. After exclusions, 159 patients (154 DTC, 5 ATC) remained to be studied. The MACIS score was less than 6 in 105 patients (66·0 per cent), 6–6·99 in 19 (11·9 per cent), 7–7·99 in 14 (8·8 per cent) and 8 or more in 21 (13·2 per cent), with corresponding disease‐specific 5‐year mortality rates of 0, 5, 14 and 86 per cent. For TNM7 the distribution was stage I in 53·5 per cent (85 patients), stage II in 10·1 per cent (16), stage III in 14·5 per cent (23) and stage IV in 22·0 per cent (35), and differed from that for TNM8: 76·7 per cent (122), 10·7 per cent (17), 4·4 per cent (7) and 8·2 per cent (13) respectively (P < 0·001). Overall disease‐specific 5‐year mortality rates by stage for TNM7 versus TNM8 were: stage I, 0 of 85 versus 3 of 100 (P = 0·251); stage II, 0 of 16 versus 6 of 16 (P = 0·018); stage III, 3 of 23 versus 2 of 7 (P = 0·565); stage IV, 20 of 32 versus 11 of 11 (P = 0·020).

Conclusion

Compared with TNM7, TNM8 downstaged more patients to stage I and accurately reflected worse prognosis for stage IV disease. TNM8 is an inferior predictor of mortality compared with MACIS.

Papillary thyroid carcinoma presenting as a primary renal tumor with multiple pulmonary and bone metastases: a case report

Background

Papillary thyroid carcinoma is the most common endocrine malignancy. Distant metastasis from differentiated thyroid carcinoma is infrequent and the metastasis rate of papillary thyroid carcinoma is lower than that of follicular thyroid carcinoma. Distant metastases from differentiated thyroid carcinoma are usually seen in the lungs and bones; however, renal metastasis is very rare.

Case presentation

Here we describe an 85-year-old Caucasian woman who presented with right flank pain 10 years ago. We describe a case of papillary thyroid carcinoma presenting as a primary renal tumor with extensive pulmonary and bone metastases. Abdominal screening with computed tomography revealed a mass on her right kidney, which was considered a primary renal cell carcinoma and she underwent a right nephrectomy. Unexpectedly, papillary thyroid carcinoma metastasis was diagnosed from demonstrative histopathological findings, such as positive immunoperoxidase staining for thyroglobulin. A total thyroidectomy was performed. Unenhanced thoracic computed tomography and skeletal scintigraphy revealed bilateral multiple nodules in her lungs and bone metastasis on T10 vertebra and right sacroiliac joint. Initially, 30 Gy radiotherapy was implemented to her T9–10 vertebrae and then she was treated with a total of 800 mCi radioactive iodine for ablation. A radioactive iodine whole body scan was performed after each 200 mCi and continuous progression was shown in each scan. After she was lost to follow-up for 3 years, she referred to our clinic again with a draining mass on her neck and we planned radiotherapy to this giant mass.

Conclusion

Our patient was surprisingly still alive after metastatic disease was diagnosed 10 years ago and she had no major complaint other than a draining mass on her neck. Our primary aim by sharing this case is to underline potential renal metastasis from papillary thyroid carcinoma. In other words, when approaching primary renal tumors, possible distant metastases of other organs need to be kept in mind for differential diagnosis. In addition, it should be noted that if managed appropriately, the long-term survival in patients with papillary thyroid carcinoma with multiple organ metastases could be encouraging.