Papillary thyroid cancer treated at the Mayo Clinic, 1946 through 1970: initial manifestations, pathologic findings, therapy, and outcome

The Surgical Management of Intracranial Metastasis Secondary to Follicular Cell-Derived Thyroid Carcinoma

BACKGROUND

Intracranial metastases (ICM) from follicular cell-derived thyroid carcinoma (FCDTC) are rare and are associated with a poor prognosis. The objective of this study is to report our experience in the surgical management of patients with ICM secondary to FCDTC.

METHODS

Patients with FCDTC who underwent surgical resection of an ICM were identified at our institution from 1998 to 2018.

RESULTS

Thirty-two patients were included in this study. Nineteen patients (59%) had involvement of the brain parenchyma only, 8 (25%) had a dural-based metastasis, 3 (9%) had a calvarial metastasis with dural extension, and 2 (6%) had a skull base metastasis with dural extension. In patients who had an R0-1 resection, the estimated lesional control at the site of resection was 91% at 3 years. However, overall ICM control was 37% at 3 years due to the progression of other ICM lesions. The 1-year disease-specific survival (DSS) was 87% and 5-year DSS was 37%.

CONCLUSIONS

ICM management in FCDTC is based on the size, number, and location of metastatic lesions. Complete resection of ICM may provide lesional control at the site of resection, however, DSS is poor due to the presence of other ICMs and metastases at multiple distant sites.

Hashimoto Thyroiditis and Mortality in Patients with Differentiated Thyroid Cancer: The National Epidemiologic Survey of Thyroid Cancer in Korea and Meta-Analysis

BACKGRUOUND

Many studies have shown that Hashimoto's thyroiditis (HT) acts as a protective factor in differentiated thyroid cancer (DTC), but little is known about its effects on mortality. Therefore, this study was performed to reveal the prognosis of HT on mortality in patients with DTC.

METHODS

This study included two types of research.

RESULTS

retrospective cohort study using the National Epidemiologic Survey of Thyroid cancer (NEST) in Korea and meta-analysis study with the NEST data and eight selected studies.

RESULTS

Of the 4,398 patients with DTC in NEST, 341 patients (7.8%) died during the median follow-up period of 15 years (interquartile range, 12.3 to 15.6). Of these, 91 deaths (2.1%) were related to DTC. HT was associated with a smaller tumor size and less aggressive DTC. In Cox regression analysis after adjusting for age and sex, patients with HT showed a significantly lower risk of all-cause death (hazard ratio [HR], 0.71; 95% confidence interval [CI], 0.52 to 0.96) and DTC-related death (HR, 0.33; 95% CI, 0.14 to 0.77). The analysis with inverse probability of treatment weight data adjusted for age, sex, and year of thyroid cancer registration showed similar association. The meta-analysis showed that patients with HT showed a lower risk of all-cause mortality (risk ratio [RR], 0.24; 95% CI, 0.13 to 0.47) and thyroid cancer-related mortality (RR, 0.23; 95% CI, 0.13 to 0.40) in comparison with patients without HT.

CONCLUSION

This study showed that DTC co-presenting with HT is associated with a low risk of advanced DTC and presents a low risk for all-cause and DTC-related death.

A study of variation in therapeutic approach to low-risk differentiated thyroid cancer in the UK

BACKGROUND

The British Thyroid Association and American Thyroid Association guideline definitions for low-risk differentiated thyroid cancers are susceptible to differing interpretations, resulting in different clinical management in the UK.

OBJECTIVE

To explore the national effect of these guidelines on the management of low-risk differentiated thyroid cancers.

METHODS

Anonymised questionnaires were sent to multidisciplinary teams performing thyroidectomies in the UK. Risk factors that multidisciplinary teams considered important when managing low-risk differentiated thyroid cancers were established.

RESULTS

Most surgeons (71 out of 75; 94.7 per cent) confirmed they were core multidisciplinary team members. More than 80 per cent of respondents performed at least 30 hemi- and/or total thyroidectomies per annum. A majority of multidisciplinary teams (50 out of 75; 66.7 per cent) followed British Thyroid Association guidelines. Risk factors considered important when managing low-risk differentiated thyroid cancers included: type of tumour histology findings (87.8 per cent), tumour size of greater than 4 cm (86.5 per cent), tumour stage T3b (85.1 per cent) and central neck node involvement (85.1 per cent). Extent of thyroid surgery (e.g. hemi- or total thyroidectomy) was highly variable for low-risk differentiated thyroid cancers.

CONCLUSION

Management of low-risk differentiated thyroid cancers is highly variable, leading to a heterogeneous patient experience.

In search of new stratification strategies: tissue proteomic profiling of papillary thyroid microcarcinoma in patients with localized disease and lateral neck metastases

INTRODUCTION

Papillary thyroid carcinomas (PTC) are the most common thyroid malignancies that are often diagnosed as microcarcinomas when the tumor is less than one centimetre in diameter. Currently, there are no valid stratification strategies that would reliably assess the risk of lateral neck metastases and optimize surgical treatment.

MATERIALS AND METHODS

Aiming to find potential tissue biomarkers of metastatic potential, we conducted a cross-sectional proteomic pilot study on formalin-fixed paraffin-embedded tissues of metastatic (N = 10) and non-metastatic (N = 10) papillary thyroid microcarcinoma patients. Samples were analysed individually using liquid chromatography/mass spectrometry, and the differentially expressed proteins (DEP) were functionally annotated.

RESULTS

We identified five overexpressed DEPs in the metastatic group (EPB41L2, CSE1L, GLIPR2, FGA and FGG) with a known association to tumour biology. Using bioinformatic-based tools, we found markedly different profiles of significantly enriched biological processes between the two groups.

CONCLUSIONS

The identified DEPs might have a role as potential tissue biomarkers for PTC metastases. However, further prospective research is needed to confirm our findings.

Causal inference between aggressive extrathyroidal extension and survival in papillary thyroid cancer: a propensity score matching and weighting analysis

Background

Extrathyroidal extension is a major risk factor for poor prognosis in papillary thyroid cancer. However, the effect of different degrees of extrathyroidal extension on prognosis remains controversial. We performed a retrospective study to elucidate how the extent of extrathyroidal extension in papillary thyroid cancer affected the clinical prognosis of patients and its covariates.

Methods

The study included 108,426 patients with papillary thyroid cancer. We categorized the extent of extension into none, capsule, strap muscles, and other organs. Three causal inference methods for retrospective studies, namely, inverse probability of treatment weighting, standardized mortality ratio weighting, and propensity score matching analysis, were used to minimize potential selection bias. Kaplan-Meier analysis and univariate Cox regression analyses were applied to analyze the precise effect of ETE on survival in papillary thyroid cancer patients.

Results

In the Kaplan-Meier survival analysis, only extrathyroidal extension into or beyond the strap muscles was statistically significant for both overall survival (OS) and thyroid cancer-specific survival (TCSS). In univariate Cox regression analyses before and after matching or weighting based on causal inference, extrathyroidal extension into soft tissues or other organs is a high-risk factor for both overall survival and thyroid cancer-specific survival. Sensitivity analysis revealed that lower overall survival was observed in patients with older age (≥55) and larger tumor size (>2 cm) of papillary thyroid cancer with extrathyroidal extension into or beyond the strap muscles.

Conclusions

Our study indicates that extrathyroidal extension into soft tissues or other organs is a high-risk factor in all papillary thyroid cancer. Even though invasion into the strap muscles did not seem to be a marker for poor prognosis, it still impaired the overall survival of patients with older age (≥55 years old) or larger tumor size (>2 cm). Further investigation is needed to confirm our results and to clarify further risk factors independent of extrathyroidal extension.

Brain metastases of papillary thyroid carcinoma origin are derived from aggressive histologic variants and demonstrate similar adverse morphology in the metastatic lesion

BACKGROUND

Distant metastases of papillary thyroid carcinoma are exceedingly rare. We analyzed all cases of brain metastases of papillary thyroid cancer at our institution and performed a literature review over the past ten years to identify histologic and molecular features of primary and metastatic tumors.

METHODS

Following institutional review board approval, the entire pathology archives at our institution were searched for cases of papillary thyroid carcinoma metastatic to brain. Patient demographics, histologic features of both primary and metastatic tumors, molecular information, and clinical outcomes were investigated.

RESULTS

We identified 8 cases of metastatic papillary thyroid carcinoma to brain. The average age at time of diagnosis of metastases was 56.3 years (range: 30-85). Average time from diagnosis of primary thyroid cancer to brain metastasis was 9.3 years (range: 0-24 years). All primary thyroid carcinomas demonstrated aggressive sub-types which were correspondingly seen in brain metastases. Next-generation sequencing revealed the most common mutations were identified in BRAFV600E, NRAS, and AKT1 with one tumor harboring a TERT promoter mutation. Six out of eight patients were deceased at the time of study with an average survival time of 2.3 years (range: 0.17-7 years) following diagnosis of brain metastasis.

CONCLUSIONS

Based on our study, it is highly unlikely that a low-risk variant of papillary thyroid carcinoma will metastasize to the brain. Therefore, careful and accurate reporting of the papillary thyroid carcinoma subtype in primary thyroid tumors is warranted. Certain molecular signatures are associated with more aggressive behavior and worse patient outcomes and next-generation sequencing should be performed on metastatic lesions.

Guideline for the Surgical Management of Locally Invasive Differentiated Thyroid Cancer From the Korean Society of Head and Neck Surgery

The aim of this study was to develop evidence-based recommendations for determining the surgical extent in patients with locally invasive differentiated thyroid cancer (DTC). Locally invasive DTC with gross extrathyroidal extension invading surrounding anatomical structures may lead to several functional deficits and poor oncological outcomes. At present, the optimal extent of surgery in locally invasive DTC remains a matter of debate, and there are no adequate guidelines. On October 8, 2021, four experts searched the PubMed, Embase, and Cochrane Library databases; the identified papers were reviewed by 39 experts in thyroid and head and neck surgery. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess the quality of evidence, and to develop and report recommendations. The strength of a recommendation reflects the confidence of a guideline panel that the desirable effects of an intervention outweigh any undesirable effects, across all patients for whom the recommendation is applicable. After completing the draft guidelines, Delphi questionnaires were completed by members of the Korean Society of Head and Neck Surgery. Twenty-seven evidence-based recommendations were made for several factors, including the preoperative workup; surgical extent of thyroidectomy; surgery for cancer invading the strap muscles, recurrent laryngeal nerve, laryngeal framework, trachea, or esophagus; and surgery for patients with central and lateral cervical lymph node involvement. Evidence-based guidelines were devised to help clinicians make safer and more efficient clinical decisions for the optimal surgical treatment of patients with locally invasive DTC.

Facility Volume as a Prognosticator of Survival in Locally Advanced Papillary Thyroid Cancer

OBJECTIVES

To evaluate the influence of facility case-volume on survival in patients with locally advanced papillary thyroid cancer (PTC), and to identify prognostic case-volume thresholds for facilities managing this patient population.

STUDY DESIGN

Retrospective database study.

METHODS

The 2004-2017 National Cancer Database was queried for patients receiving definitive surgery for locally advanced PTC. Using K-means clustering and multivariable Cox proportional-hazards (CPH) regression, two groups with distinct spectrums of facility case-volumes were generated. Multivariable CPH regression and Kaplan-Meier analysis assessed for the influence of facility case-volume and the prognostic value of its stratification on overall survival (OS).

RESULTS

Of 48,899 patients treated at 1304 facilities, there were 34,312 (70.2%) females and the mean age was 48.0 ± 16.0 years. Increased facility volume was significantly associated with reduced all-cause mortality (HR 0.996; 95% CI, 0.992-0.999; p = 0.008). Five facility clusters were generated, from which two distinct cohorts were identified: low (LVF; <27 cases/year) and high (HVF; ≥27 cases/year) facility case-volume. Patients at HVFs were associated with reduced mortality compared to those at LVFs (HR 0.791; 95% CI, 0.678-0.923, p = 0.003). Kaplan-Meier analysis of propensity score-matched N0 and N1 patients demonstrated higher OS in HVF cohorts (all p < 0.001).

CONCLUSIONS

Facility case-volume was an independent predictor of improved OS in locally advanced PTC, indicating a possible survival benefit at high-volume medical centers. Specifically, independent of a number of sociodemographic and clinical factors, facilities that treated ≥27 cases per year were associated with increased OS. Patients with locally advanced PTC may, therefore, benefit from referrals to higher-volume facilities.

LEVEL OF EVIDENCE

4 Laryngoscope, 133:443-450, 2023.

Screening and treatment of brain metastasis from papillary thyroid carcinoma: a case series

BACKGROUND

The brain metastasis from differentiated thyroid carcinoma (DTC) is a rare condition and its prognosis is poor. The standard protocol for screening and treatment of patients with brain metastases from papillary thyroid cancer (PTC) remains controversial. This report aims to share the experience of a single center in the management of brain metastases from DTC.

MATERIAL AND METHODS

Five patients with brain metastases were identified from 5000 patients with DTC attending the department of nuclear medicine, Hospital 108 between 2016 to 2022. The statistical software Statistical Package for Social Sciences (SPSS) 20.0 (SPSS Inc., Chicago, IL, USA) was used to analyze the data.

RESULTS

Five patients with brain metastases from DTC were revealed by MRI, ¹⁸F-FDG PET/CT with contrast enhancement, and ¹³¹I-SPECT/CT. The median time of overall survival (OS) was 15 months, ranging from 10 to 65 months. Two out of the five patients underwent surgery, and futher 2 patients were treated with stereotactic surgery (SRS). All patients are still alive.

CONCLUSIONS

Brain metastases from DTC are rare. MRI is the preferred imaging mobility to screen brain lesions in DTC. The primary treatment modalities are surgery and SRS.

TERT genetic polymorphism rs2736100 is associated with an aggressive manifestation of papillary thyroid carcinoma

Objectives

TERT rs2736100 genetic polymorphism is commonly found in human malignancies, indicating its key role in cancer cell transformation. The aim of this study is to investigate the effects of the functional TERT rs2736100 genetic polymorphism on the outcomes of papillary thyroid carcinoma (PTC) patients.

Materials and methods

We performed a retrospective study on the relationship between rs2736100 and clinicopathological outcomes of PTC in 500 patients (378 females and 122 males) aged 43.8 ± 11.4 years (range 15-74 years) with a median follow-up of 60 months (range, 1-455 months).

Results

TERT rs2736100 genetic polymorphism (TG/GG vs. TT) was significantly associated with several high-risk clinicopathological features such as tumor spread, extrathyroidal extension, central/lateral lymph node metastases, and Stage T III or IV disease. However, in Kaplan-Meier survival analyses, the rs2736100 mutation was unrelated to overall disease-free survival with a log-rank value of p > 0.05. In Cox-regression analyses, the overall survival rate of recurrence/neo-metastasis was related to a larger tumor size, younger age, and tumor spread but unrelated to the rs2736100 mutation.

Conclusions and significance

TERT rs2736100 genetic polymorphism mutation is more likely to manifest with aggressive clinicopathological characteristics but cannot worsen prognosis in PTC.

Propensity score matching analysis of adjuvant external-beam radiotherapy for the treatment of papillary thyroid carcinoma with other organ invasions

PURPOSE

The role of adjuvant external-beam radiotherapy (EBRT) in the treatment of locally advanced papillary thyroid carcinoma (PTC) remains controversial due to the lack of prospective data and the conflicting retrospective data. This study aimed to determine the benefits of adjuvant EBRT in patients with PTC and other organ invasions using propensity score matching to reduce the heterogeneity of the patient population.

METHODS

Data from patients with PTC with other organ invasions but no distant metastases who underwent surgery and adjuvant radioactive iodine (RAI) alone (Non-EBRT group) or adjuvant EBRT plus RAI (EBRT group) were retrospectively reviewed. Propensity matching was used to reduce heterogeneity. Survival outcomes and toxicities associated with EBRT were evaluated.

RESULTS

Between January 2005 and December 2019, 102 patients in the Non-EBRT group and 26 patients in the EBRT group were evaluated. In the 48 propensity score-matched patients, no significant differences in baseline characteristics between the Non-EBRT and EBRT groups were detected. The locoregional recurrence-free survival (LRRFS) and recurrence-free survival (RFS) rates were significantly higher in the EBRT group compared with the rates in the Non-EBRT group (5y-LRRFS: 100% vs. 74%, p = 0.003, 5y-RFS: 91% vs. 74%, p = 0.035). EBRT was well-tolerated, with no grade ≥ 3 toxicity, and all patients completed the therapy as planned.

CONCLUSION

Adjuvant EBRT plus RAI exhibited acceptable toxicity and improved LRRFS and RFS in patients with PTC with other organ invasions compared with RAI alone.

Circumferential Laryngotracheal Resection in Thyroid Cancer: Experience and Outcome in a Single Center

There is limited experience of laryngotracheal resection in patients with differentiated thyroid carcinoma (DTC). The aim of this study was to report our experience of circumferential laryngotracheal resection in DTC and its long-term outcome. In this retrospective study, 10 patients of locally invasive DTC who underwent circumferential laryngotracheal resection between January 2000 and December 2015 were included. Clinicopathologic profile and follow up was noted. Mean age of the cohort was 50.1 ± 7.8 years (M:F = 1: 2.3). Papillary carcinoma was the commonest pathology (60%) followed by follicular carcinoma (20%), 10% each had Hurthle cell and poorly differentiated thyroid carcinoma. Sixty percent patients presented with recurrent or persistent disease and 20% with distant metastases. Vocal cord palsy was observed in 30%. Fifty percent patients underwent tracheal resection with end to end anastomosis and remaining laryngotracheal resection. Carotid artery resection and anastomosis was performed in one patient. Shin stage IV invasion was observed in 80% and stage III in remaining. There was no perioperative mortality. All patients received adjuvant radioiodine therapy and 40% external beam radiotherapy. Median follow up was 48 months. One patient who earlier had tracheal resection underwent total laryngectomy due to recurrent disease after 24 months. Forty percent patients developed distant metastases during follow-up. Mean survival was 77.8 months (CI = 63.0-92.5). Five-year overall survival was 60% and was significantly high in those without distant metastases (p = 0.006). The outcome of circumferential larygotracheal resections for DTC is excellent in terms of local disease control and long term survival.

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.

Pathological Analysis of Encased Resected Recurrent Nerves in Locally Invasive Thyroid Cancer

Simple Summary

Thyroid cancer encasing the recurrent nerve is rare, and the decision to resect or preserve the nerve is multifactorial. The aim of this retrospective study was to evaluate the rate of actual invasion of the nerve beyond the nerve sheath in cancers encasing the nerve. Fifty-two patients were included: 7 cases of medullary thyroid carcinoma, 8 papillary thyroid carcinomas in children and 37 follicular derived cancers in adults. Tumor-related vocal fold paralysis was present in 30% of cases. The nerve was invaded in 82% of follicular cell-derived tumors, 88% of pediatric cases, and 100% of medullary carcinomas. Only agressive histology was a risk factor for nerve invasion. Vocal fold paralysis was not predictive. To our knowledge, this is one of the largest series with pathologic analysis of resected recurrent nerves, showing a high rate of nerve invasion in these rare cases of cancer encasing the reucrrent nerve.

Abstract

Objective: Thyroid cancer encasing the recurrent nerve is rare, and the decision to resect or preserve the nerve is multifactorial. The objective of this study was to histopathologically analyze resected encased nerves to assess the rate of nerve invasion and risk factors. Materials and Methods: A retrospective study was carried out on consecutive patients with resection of the recurrent nerve for primary or recurrent follicular cell-derived or medullary thyroid carcinoma from 2005 to 2020. Demographics, pathology, locoregional invasion, metastases, recurrences and survival were analyzed. Slides were reviewed blindly by two specialized pathologists (AAG, RC) for diagnosis of invasion deep to the epineurium. Results: Fifty-two patients were included: 25 females; average age, 55 (range 8–87). In total, 87% percent (45/52) were follicular cell-derived with 17/45 (37.8%) aggressive variants; 13% (7/52) were medullary carcinoma. Preoperative vocal fold (VF) paralysis was present in 16/52 (30.7%). Pathologically, the nerve was invaded in 44/52 cases (85%): 82% of follicular cell-derived tumors (37/45), 88% of pediatric cases, and 100% of medullary carcinomas (7/7). Nerve invasion was observed in 11/16 (69%) with preoperative VF paralysis and 33/36 (92%) with normal VF function. Only aggressive histology was correlated with nerve invasion in follicular cell-derived tumors (p = 0.019). Conclusions: The encased nerves were pathologically invaded in 82% of follicular cell-derived tumors and in 100% of medullary carcinomas. Nerve invasion was statistically correlated with aggressive histopathological subtypes and was observed in the absence of VF paralysis in 92% of cases.

Clinicopathological features and prognosis of papillary thyroid cancer patients with type 2 diabetes mellitus

BACKGROUND

The clinicopathological characteristics of patients with papillary thyroid carcinoma (PTC) combined with type 2 diabetes mellitus (T2DM) and patients with PTC alone were explored and compared in order to provide a more reasonable treatment plan for the clinical diagnosis and treatment of these patients.

METHODS

A total of 1,771 patients from January 2017 to December 2019 who underwent PTC surgery for the first time in the west branch of the Fourth Hospital of Hebei Medical University were analyzed retrospectively. Among them, 111 patients had PTC with T2DM (D-T group) and 1,660 patients had PTC alone (PTC group). The differences in general data and clinical characteristics between the D-T group and the PTC group were analyzed.

RESULTS

There were statistically significant differences in age, gender, and body mass index (BMI) between the D-T group and PTC group (P<0.05). Multifocality and extra-glandular invasion in the D-T group were significantly higher than the PTC group (P<0.05). In women, the D-T group was older, had a higher BMI, and was more likely to have extra-glandular invasion (P<0.05) than the PTC group. The prognosis of the D-T group was worse than that of the PTC group as determined by 3 well-developed prognostic staging systems, 8th AJCC TNM staging, MAGIS SCORE, AMES staging, and the results were statistically significant (P=0.001, P<0.001, P=0.021).

CONCLUSIONS

Our study showed that the overall prognosis of PTC patients with T2DM was worse than that of patients with PTC alone. At the same time, especially in patients younger than 55 years of age, multifocal carcinoma and extra-glandular invasion are likely to occur. In addition, female patients with T2DM are more likely to have extra-glandular invasion than male patients. Therefore, for such patients, preoperative evaluation should be fully conducted.

Optimization of follow-up in patients with papillary thyroid cancer who show no evidence of disease 9-12 months after treatment

BACKGROUND

Papillary thyroid cancer (PTC) has an excellent prognosis, and recurrence is rare in patients with no evidence of disease (NED) after initial treatment. Despite this, several guidelines recommend long and costly follow-up, with limited evidence of improved patient outcomes. This study aims to examine the value of follow-up in patients with NED after treatment for PTC, by determining the rate of recurrence, recurrence-associated morbidity, and death, and whether any recurrence was diagnosed through the follow-up programme.

METHODS

Patients operated for PTC at Lund University Hospital between January 2004 and December 2016 were eligible. Patients with T1a N0/NX were excluded as well as patients with any other thyroid malignancy. Data were collected retrospectively by searching the patients' medical records. NED was defined as thyroglobulin less than 1 ng/ml, thyroglobulin antibodies less than 20 kIU/l, and negative imaging. Biochemical recurrence was defined as thyroglobulin greater than 1 ng/ml, and/or thyroglobulin antibodies greater than 20 kIU/l. Structural recurrence was defined as a strong suspicion of recurrence on imaging and/or histological proof of recurrence.

RESULTS

Out of a cohort of 187 patients, there were 90 patients with NED who were followed for a median of 6.3 years. Three patients had biochemical recurrence; none of them had symptoms, nor were they treated for their recurrence. Three had structural recurrence; all were above 75 years old and only one was diagnosed through the follow-up programme. No patient died of PTC; five patients died during the follow-up.

CONCLUSION

Follow-up as it is designed today cannot identify recurrences accurately and seems to be of questionable benefit in younger patients with NED after treatment for PTC.

The Overdiagnosis of Thyroid Micropapillary Carcinoma: The Rising Incidence, Inert Biological Behavior, and Countermeasures

The incidence of papillary thyroid microcarcinoma (PTMC) has exponentially increased in the past three decades. The 2014 World Cancer Report stated that, among the new cases of thyroid carcinoma, >50% are PTMC. The incidence of thyroid cancer was growing by 20.1% annually in China. Most of PTMC have low risk and excellent prognoses. It must be realized that the problem of overdiagnosis of thyroid cancer is quite serious. In this article, we summarized the phenomenon and the cause of "overdiagnosis" of PTMC, the progress of clinical management, and the countermeasures.

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.

Data set for reporting carcinoma of the thyroid: recommendations from the International Collaboration on Cancer Reporting

Thyroid cancer therapy is increasingly tailored to patients' risk of recurrence and death, placing renewed importance on pathologic parameters. The International Collaboration on Cancer Reporting (ICCR), an organization promoting evidence-based, internationally agreed-upon standardized pathology data sets, is the ideal conduit for the development of a pathology reporting protocol aimed at improving the care of patients with thyroid carcinomas. An international expert panel reviewed each element of thyroid pathology reporting. Recommendations were made based on the most recent literature and expert opinion.The data set uses the most recent World Health Organization (WHO) classification for the purpose of a more clinically and prognostically relevant nomenclature. One example is the restriction of the term minimally invasive follicular carcinoma to tumors with capsular invasion only. It reinforces the already established criteria for blood vessel invasion adopted by the most recent WHO classification and Armed Forces Institute of Pathology fascicle. It emphasizes the importance of the extent of blood vessel invasion and extrathyroid extension to better stratify patients for appropriate therapy. It is the first data set that requires pathologists to use the more recently recognized prognostically powerful parameters of mitotic activity and tumor necrosis. It highlights the importance of assessing nodal disease volume in predicting the risk of recurrence.The ICCR thyroid data set provides the tools to generate a report that will guide patient treatment in a more rational manner aiming to prevent the undertreatment of threatening malignancies and spare patients with indolent tumors the morbidity of unnecessary therapy. We recommend its routine use internationally for reporting thyroid carcinoma histology.

Risk Factors and a Prediction Model of Lateral Lymph Node Metastasis in CN0 Papillary Thyroid Carcinoma Patients With 1-2 Central Lymph Node Metastases

BACKGROUND

Papillary thyroid cancer (PTC) in clinically lymph node-negative (cN0) patients is prone toward lymph node metastasis. As a risk factor for tumor persistence and local recurrence, lateral lymph node metastasis (LLNM) is related to the number of central lymph node metastases (CLNMs).

METHODS

We performed LLNM risk stratification based on the number of CLNMs for cN0 PTC patients who underwent thyroidectomy and lymph node dissection between January 2013 and December 2018. A retrospective analysis was applied to the 274 collected patients with 1-2 CLNMs. We examined the clinicopathological characteristics of the patients and constructed a LASSO model.

RESULTS

In the 1-2 CLNM group, tumors >10 mm located in the upper region and nodular goiters were independent risk factors for LLNM. Specifically, tumors >20 mm and located in the upper region contributed to metastasis risk at level II. Hashimoto's thyroiditis reduced this risk (p = 0.045, OR = 0.280). Age ≤ 30 years and calcification (microcalcification within thyroid nodules) correlated with LLNM. The LASSO model divided the population into low- (25.74%) and high-risk (57.25%) groups for LLNM, with an AUC of 0.715.

CONCLUSIONS

For patients with 1-2 CLNMs, young age, calcification, nodular goiter, tumor >10 mm, and tumor in the upper region should alert clinicians to considering a higher occult LLNM burden. Close follow-up and therapy adjustment may be warranted for high-risk patients.

Surgical treatment of locally advanced thyroid cancer

Operations in this area are demanding and require special experience in endocrine, thoracic and vascular surgery, an experienced anaesthesiologist, as well as the interdisciplinary cooperation with other medical specialists (nuclear medicine, oncology, radiology, otolaryngology). A reliable system of surgical guidelines has been developed from a few individual publications with special impact.

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

OBJECTIVES/HYPOTHESIS

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

STUDY DESIGN

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

4 Laryngoscope, 131:1026-1034, 2021.

Predictive factors of contralateral occult carcinoma in patients with papillary thyroid carcinoma: a retrospective study

BACKGROUND

The surgical approach toward unilateral papillary thyroid carcinoma (PTC) has been in controversy. One of the concerns is the existence of contralateral occult carcinoma, which could cause relapse and even lead to re-operation if not dealt with. This study aims to find out risk factors related to contralateral occult PTC, in order to facilitate in surgical approach decision for PTC.

METHODS

A total of 921 PTC patients who underwent total/near-total thyroidectomy and central lymph node dissection (CND) with/without lateral lymph node dissection (LND) from January 2014 to Sept 2017 in Guangdong General Hospital were assessed retrospectively. The relations between contralateral occult PTC and clinicopathologic characteristics of PTC were analyzed by univariate and multivariate logistic regression.

RESULTS

The incidence of contralateral occult carcinoma in patients with PTC was 16.7% (154 of 921 cases). Univariate analysis showed that multifocality of the primary carcinoma (P=0.000), lymph node metastasis (P=0.001), pathologic tumor size (P=0.014) and contralateral benign nodule (P=0.000) were significantly associated with the increased incidence of contralateral occult PTC. No significant correlations were found between contralateral carcinoma and other variables such as gender (P=0.338), age (P=0.283), BRAF mutation (P=0.187) or extrathyroidal extension (P=0.423). Multivariate logistic regression analysis revealed that contralateral benign nodule (P=0.000), multifocality (P=0.000) and lymph node metastasis (P=0.009) were independent predictors of bilateral PTC of patients whose pre-operation ultrasound (US) show a unilateral carcinoma.

CONCLUSIONS

Lymph node metastasis, contralateral benign nodule and multifocality are independent predictors of contralateral occult PTC. For unilateral PTC patients with one or more of these factors, total/near-total thyroidectomy should be considered when making surgical approach decisions.

Extrathyroidal extension predicts negative clinical outcomes in papillary thyroid cancer

BACKGROUND

The eighth edition American Joint Committee on Cancer tumor-node-metastasis staging for well-differentiated thyroid cancers, no longer considers "minimal" extrathyroidal extension for tumor staging. This change prompted us to examine the effect of extrathyroidal extension on patient outcomes.

METHODS

Patients (n = 177,497) in the 2016 National Cancer Database with classic papillary thyroid cancer were evaluated to determine the effect of extrathyroidal extension on overall survival and risk for nodal and distant metastases. Kaplan-Meier curves with the log-rank test were used to evaluate survival differences. Multivariable Cox and logistic regression analyses included relevant clinicopathologic variables (e.g. age, sex, race, and Charlson Comorbidity Index).

RESULTS

Patients with "minimal" extrathyroidal extension had worse survival versus patients with no extrathyroidal extension (10-year survival 89.3% vs 93.1%, hazard ratio 1.23; 95% confidence interval, 1.13-1.35; P < .001). Any extrathyroidal extension was associated with higher risks for lymph node (odds ratio 2.78; 95% confidence interval, 2.69-2.87) and distant metastasis (odds ratio 3.5; 95% confidence interval, 3.05-4.04). These associations persisted when comparing "micro" (extension into the thyroid capsule) versus none for nodal risk (odds ratio 1.25; 95% confidence interval, 1.18-1.33) and distant metastasis (OR 1.52; 95% confidence interval, 1.11-2.09).

CONCLUSION

All levels of extrathyroidal extension, including microscopic, were associated with increased risk for nodal and distant metastasis. Both minimal and macroscopic extrathyroidal extension were also associated with decreased overall survival. Such findings have the potential to affect the clinical decision making for patients diagnosed with papillary thyroid cancer.

Identifying the Transcriptional Regulatory Network Associated With Extrathyroidal Extension in Papillary Thyroid Carcinoma by Comprehensive Bioinformatics Analysis

Extrathyroidal extension (ETE) affects papillary thyroid cancer (PTC) prognosis. The objective of this study was to identify biomarkers for ETE and explore the mechanisms controlling its development in PTC. We performed a comprehensive bioinformatics analysis using several datasets. Differential expression analysis and weighted gene co-expression network analysis (WGCNA) on 58 paired PTC samples from The Cancer Genome Atlas (TCGA) were used to detect ETE-related mRNA and long noncoding (lnc) RNA modules and construct an lncRNA/mRNA network. An independent TCGA dataset containing 438 samples was utilized to validate and characterize the WGCNA results. Functional annotation was used to identify the biological functions and related pathways of ETE modules. Two independent RNA sequencing datasets were combined to crossvalidate relationships between lncRNAs and mRNAs by Pearson correlation analysis. Transcription factors (TFs) for affected genes were predicted using the binding motif data from Ensembl Biomart to construct a TF/lncRNA/mRNA network. Other two independent datasets were used to crossvalidate TF-mRNA associations. Finally, receiver operating characteristic, survival analyses, and Cox proportional hazard regression model were performed to explore the significance of hub genes in ETE diagnosis and PTC prognosis. Three mRNA modules and two lncRNA modules were significantly associated with ETE. Enrichment analysis showed extracellular matrix changes was closely related to the development of ETE. A TF/lncRNA/mRNA regulatory network was constructed containing 33 validated hub genes, 64 lncRNAs, and 64 TFs, all differentially expressed between ETE and non-ETE samples. Unc-5 family C-terminal like [area under the curve (AUC): 0.711], sushi repeat containing protein X-linked 2 (AUC: 0.706), lysyl oxidase (AUC: 0.704), collagen type I alpha 1 chain (AUC: 0.704), and collagen type X alpha 1 chain (AUC: 0.704) were the most highly significant hub genes for ETE diagnosis. The Cox proportional hazard regression model constructed with hub genes showed significant survival differences between low- and high-risk groups (p = 0.00025) and performed good prediction for PTC prognosis(AUC = 0.794; C-index = 0.895). The identification of 33 biomarkers and TF/lncRNA/mRNA regulatory network would provide new insights into the molecular mechanisms of ETE besides the prognosis model may have important clinical implications in the improvement of PTC risk stratification, therapeutic decision-making, and prognosis prediction.

Invasion in thyroid cancer: Controversies and best practices

Invasion is a key feature of malignancy and an important element in the classification, risk-stratification, and staging of thyroid cancers. However, the histopathologic criteria for tumor capsular invasion, angioinvasion, and extrathyroidal extension (ETE) have varied among pathologists, both in practice as well as in studies assessing the clinical significance of these findings. In this review, we provide historic context for the controversies surrounding the definition of invasion in thyroid neoplasms and highlight recent efforts to standardize how pathologists report capsular invasion, angioinvasion, and ETE. We offer practical suggestions for distinguishing invasion from its mimics and provide an algorithmic approach for classifying thyroid tumors based on integration of tumor invasiveness, nuclear atypia, and architectural pattern.

Differentiated thyroid carcinoma: a 5-years survival study at a referral hospital in Brazil

BACKGROUND

Although the prognosis of differentiated thyroid carcinoma (DTC) therapy is considered excellent over time, some cases have a poorer prognosis and evolve into death.

OBJECTIVE

This study aimed to estimate the 5-year specific survival and to identify prognosis factors in a cohort of DTC adult subjects.

METHODS

Survival probability was estimated by Kaplan-Meier's method in a retrospective hospital-based cohort study. Comparisons were made by log-rank test. Prognosis factors were identified using Cox risk modeling and crude and adjusted Hazard Ratio measures were obtained. Two models were estimated, considering age grouping of the 7th and 8th editions of TNM.

RESULTS

Specific 5-year survival in the cohort was 98.5% (95%CI: 94.2 - 97.5). Considering TNM 7th edition, the risk estimates were 9.88 (95%CI: 1.67 - 58.33) for age group ≥ 55 years, 18.87 (95%CI: 7.38 - 48.29) for individuals with distant metastasis, 6.36 (95%CI: 2.26 - 17.91) for patients who underwent lymphadenectomy and 0.16 (95%CI: 0.06 - 0.43) for those who received radioiodine therapy. For TNM 8th edition, the risk estimates were 10.12 (95%CI: 2.05 - 50.09) for age group ≥ 55 years, 12.43 (95%CI: 4.58 - 33.77) for individuals with distant metastasis, 5.06 (95%CI: 1.82 - 14.05) for patients who underwent lymphadenectomy and 0.19 (95%CI: 0.07 - 0.51) for those who received radioiodine therapy.

CONCLUSIONS

This cohort had a very high survival over a 5-year period. The prognosis was negatively influenced by age, distant metastasis and lymphadenectomy, whereas radioiodine therapy was found to be protective.

Interobserver Variability in the Histopathologic Assessment of Extrathyroidal Extension of Well Differentiated Thyroid Carcinoma Supports the New American Joint Committee on Cancer Eighth Edition Criteria for Tumor Staging

Background: Extrathyroidal extension (ETE) by papillary and follicular thyroid carcinoma can be associated with increased risk of tumor recurrence and mortality. In the seventh edition of its Cancer Staging Manual, the American Joint Committee on Cancer (AJCC) defined minimal ETE as the involvement of skeletal muscle (i.e., strap muscles) or perithyroidal soft tissue. The eighth edition of the AJCC Cancer Staging Manual has changed the criteria so that only grossly evident (macroscopic) ETE involving strap muscles (not microscopic ETE involving perithyroidal soft tissue) affects tumor staging. Summary: Concordance of identifying microscopic ETE (as well as extranodal extension by carcinoma metastatic to lymph nodes) was previously evaluated among 11 expert endocrine pathologists. The overall agreement rate was slight when rendering a diagnosis of ETE. Concordance was highest when pathologists assessed the spatial relationship of carcinoma to skeletal muscle. This article discusses the significance of these findings. It also reviews relevant anatomic and developmental considerations related to the boundaries of the thyroid. Conclusions: The results of the concordance study provide additional rationale supporting stringent criteria for diagnosing ETE, as proposed by the eighth edition of the AJCC Cancer Staging Manual. It is expected that these rigid morphologic criteria will potentially reduce interobserver variability and enhance consistency in the diagnosis and staging of thyroid carcinoma.

MicroRNA-1270 modulates papillary thyroid cancer cell development by regulating SCAI

PURPOSE

We intended to evaluate expression and mechanisms of human microRNA 1270 (hsa-miR-1270) in papillary thyroid cancer (PTC).

METHODS

In PTC cell lines and human PTC tumors, hsa-miR-1270 expressions were evaluated by qRT-PCR. Hsa-miR-1270 was downregulated in TPC1 and K1 cells via lentiviral transduction. Its effects on PTC cancer cell proliferation, migration and in vivo transplantation were assessed, respectively. Potential targeting of hsa-miR-1270 on downstream gene, Suppressor Of Cancer Cell Invasion (SCAI), was assessed. In hsa-miR-1270-downregulated PTC cells, SCAI was further downregulated to examine its associating role in hsa-miR-1270-mediated regulation on cancer cell proliferation and migration.

RESULTS

Hsa-miR-1270 was aberrantly upregulated in PTC cell lines and human PTC tumors. In TPC1 and K1 cells, lentivirus-mediated hsa-miR-1270 downregulation suppressed cancer cell proliferation, migration and in vivo transplantation. Hsa-miR-1270 binds SCAI and inversely regulated SCAI gene expression in PTC cells. SCAI downregulation removed the suppressing effects of hsa-miR-1270 downregulation in human PTC cells.

CONCLUSION

Hsa-miR-1270 downregulation may suppress human PTC cell development both in vitro and in vivo. The regulatory mechanism of hsa-miR-1270 in PTC may be primarily associated with SCAI.

Surgical outcomes of thyroid cancer patients in a tertiary cancer center in India

Background

Surgery is the mainstay in the management of thyroid cancer. Surgical outcomes need to be tempered against the excellent prognosis of the disease.

Aims

This study aims to study the surgical outcomes including the 30-day morbidity and 5-year survival of thyroid cancer patients.

Settings and Design

Retrospective analysis of a prospectively maintained surgical database in a tertiary cancer center in India.

Materials and Methods

We analyzed 221 surgically treated patients in the year 2012.

Statistical Analysis

Used IBM SPSS 24.0 (Armonk, NY) with p < 0.05.

Results

The median age was 40 years with predominantly papillary thyroid carcinoma (55%). Localized disease in 47% of cases, locoregional disease in 42.5% and distant metastasis in 10.2% of cases at presentation was noted. Treatment naïve patients were 71% and revision surgeries were done in 29% patients. Extended thyroidectomy constituted 11% of the surgeries. Temporary hypocalcemia was seen in 30.8% of patients, 5% requiring intravenous calcium supplementation. Vocal cord palsy as per nerve at risk and chyle leak were seen in 4.5% and 3.1%, respectively. Aggressive histology, extended thyroidectomy, and inadvertent parathyroidectomy were significant factors associated with complications. Five year estimated overall survival with median follow-up of 50 months was 98%, and event-free survival was 84.8%. Advanced age, distant metastasis at presentation and aggressive histology connoted poor outcomes.

Conclusion

Thyroid cancer, irrespective of the extent of disease, has good prognosis. Aggressive histology, the extent of thyroid surgery, distant metastasis and age are important factors, which should be factored in the algorithm of thyroid cancer management.

Appropriateness of Subadventitial Resection for Invasion of the Carotid Artery by Papillary Thyroid Carcinoma

BACKGROUND

Selection of surgical treatment for patients with papillary thyroid carcinoma (PTC) that includes great vessel invasion is challenging. We investigated the efficacy of tumor excision, with regard to safety of the surgical procedure and prognosis among patients with PTC invasion of the carotid or vertebral artery.

METHODS

This study is a retrospective review of patients who underwent surgical excision for PTC at our institution, between 1981 and 2010, with 49 patients treated for carotid artery invasion and nine for vertebral artery invasion.

RESULTS

Twenty patients with carotid artery invasion receiving initial treatment underwent subadventitial resection. Among 29 relapsing patients with carotid artery invasion, subadventitial resection was performed in 27 and en-block resection and reconstruction in the other two. In patients with carotid artery invasion, locoregional recurrence was identified in 14 patients, with the recurrence specific to the carotid artery in one case and distant recurrence in 15. The 10-year disease-specific survival rate was shorter among relapsing patients (21.7%) than among those receiving an initial treatment (69.3%). At 8 years after surgery, however, the survival rates were comparable between the two groups. Of the nine patients with vertebral artery invasion, two received initial treatment, with either preservation or reconstruction of the vertebral artery. The other six cases were tumor recurrences, treated by tumor and vertebral artery resection. Vertebral artery invasion was associated with carotid artery invasion in five patients and subclavian artery invasion in four.

CONCLUSIONS

Carotid artery invasion by PTC did not extend beyond the adventitia of the artery in the majority of patients. Most patients with vertebral artery invasion required tumor excision with vertebral artery resection.

Papillary Thyroid Carcinoma (PTC) in Children and Adults: Comparison of Initial Presentation and Long-Term Postoperative Outcome in 4432 Patients Consecutively Treated at the Mayo Clinic During Eight Decades (1936-2015)

BACKGROUND

Contemporary guidelines for managing PTC advise an approach wherein primary tumor and regional metastases (RM) are completely resected at first surgery and radioiodine remnant ablation (RRA) is restricted to high-risk patients, policies our group has long endorsed. To assess our therapeutic efficacy, we studied 190 children and 4242 adults consecutively treated during 1936-2015.

SUBJECTS AND METHODS

Mean follow-up durations for children and adults were 26.9 and 15.2 years, respectively. Bilateral lobar resection was performed in 86% of children and 88% of adults, followed by RRA in 30% of children and 29% of adults; neck nodes were excised in 86% of children and 66% of adults. Tumor recurrence (TR) and cause-specific mortality (CSM) details were taken from a computerized database.

RESULTS

Children, when compared to adults, had larger primary tumors which more often were grossly invasive and incompletely resected. At presentation, children, as compared to adults, had more RM and distant metastases (DM). Thirty-year TR rates were no different in children than adults at any site. Thirty-year CSM rates were lower in children than adults (1.1 vs. 4.9%; p = 0.01). Comparing 1936-1975 (THEN) with 1976-2015 (NOW), 30-year CSM rates were similar in MACIS <6 children (p = 0.67) and adults (p = 0.08). However, MACIS <6 children and adults in 1976-2015 had significantly higher recurrence at local and regional, but not at distant, sites. MACIS 6+ adults, NOW, compared to THEN, had lower 30-year CSM rates (30 vs. 47%; p < 0.001), unassociated with decreased TR at any site.

CONCLUSIONS

Children, despite presenting with more extensive PTC when compared to adults, have postoperative recurrences at similar frequency, typically coexist with DM and die of PTC less often. Since 1976, both children and adults with MACIS <6 PTC have a <1% chance at 30 years of CSM; adults with higher MACIS scores (6 or more) have a 30-year CSM rate of 30%.

Crucial parameters in thyroid carcinoma reporting - challenges, controversies and clinical implications

In the modern era, a pathology report of thyroid carcinoma requires the inclusion of numerous prognostically relevant histopathological features, e.g. the presence and extent of vascular and capsular invasion, extrathyroidal extension, the surgical margin status and the characteristics of nodal metastasis. These pathological features are crucial components of the initial risk stratification to determine the need for completion thyroidectomy and/or postoperative radioactive iodine ablation therapy. The current review aims to summarise the diagnostic criteria, the controversies, the prognostic impacts and the challenges of these pathological characteristics, focusing specifically on the parameters that are incorporated into the American Joint Committee on Cancer (AJCC) staging system, the College of American Pathologists (CAP) reporting template, the American Thyroid Association (ATA) and the National Comprehensive Cancer Network (NCCN) guidelines.

Eliminating the Age Cutoff in Staging of Differentiated Thyroid Cancer: The Safest Road?

BACKGROUND

Unlike virtually all other cancer types, thyroid cancer is unique in that patient age is a key component in its staging. Pathologists and clinicians worldwide have accepted an age cutoff of 45 years for staging; in 2018, this advances to age 55 years in the eighth edition of the American Joint Commission on Cancer staging system.

EVIDENCE ACQUISITION

Clinical and basic research studies, reviews, and previous editions of consensus statements regarding thyroid cancer staging were reviewed, with particular focus on the influence of age in thyroid cancer prognosis.

PURPOSE

This perspective briefly reviews the basis for this practice and challenges it as no more appropriate than for other malignancies.

EVIDENCE SYNTHESIS

The majority of findings report an association of age with thyroid cancer survival but do not support a specific age cutoff; rather, they suggest that outcome is affected by age as a continuous variable. Conceivably, other factors interact with age on a continuous basis over time, affecting prognosis. When identified, these factors could alter our current concept of the importance of an age cutoff in staging.

CONCLUSIONS

Among all cancers, age has an important role in only thyroid cancer staging. The consideration of age as a continuous variable and the search for age-associated prognostic variables could elucidate a more accurate staging system.

Follicular Thyroid Carcinoma with a Predominant Insular Component in a Child: A Case Report

Thyroid carcinoma is rare in children and differs from its adult counterpart in many aspects, including that childhood thyroid carcinomas are all well differentiated. Here we present a 14-year-old female from a goitrous area with follicular thyroid carcinoma with a predominant insular component. The child was well without recurrence or metastases after 5 years of follow-up.

Solitary Brain Metastases from Thyroid Carcinoma: Study of 6 Cases

Aims and background

Although systemic metastases from thyroid cancer are relatively frequent, they rarely affect the nervous system and only exceptionally originate from well-differentiated carcinoma.

Methods

The authors describe 6 cases of solitary brain metastases from thyroid carcinoma, well-differentiated in 3 cases and anaplastic in the other 3 cases.

Results

Four patients were females and 2 males (M:F ratio, 1:2); average age was 51 yrs (range 48-56). On average, the interval between diagnosis of the thyroid tumor and appearance of the metastasis was 2.8 years (range 1-12 years) and was shorter in the anaplastic forms (1.2 versus 4.4 years). Average survival was 15 months (range 6-48 months); in particular, average survival was longer in patients with well-differentiated carcinoma (9 vs 21 months) as also in those who did not present other metastatic sites (6 vs 24 months). Death was due to systemic progression of the disease in 4 cases and to brain-relapse in the other 2 cases.

Conclusions

Surgery, radioactive iodine (where uptake is demonstrable), and radiotherapy are the main therapies available for metastases from thyroid carcinoma. However, survival of patients appears to be modified by the type of treatment performed.

Brain Metastases in Well-Differentiated Carcinoma of the Thyroid

Fifteen patients (4 males and 11 females) developed brain metastases from well-differentiated thyroid cancer within 1 month to 14 years of the initial diagnosis. One patient presented with a brain tumor. Except for 3 patients with unique brain metastases, all the others had extensive metastases in nodes, lungs and bones in various combinations. Brain metastases generally appeared after the onset of metastases at other sites. The histology of the brain tumor matched the primary pathology in the 6 operated cases. The treatment was surgery and external radiation in 6 cases, and radioiodine or chemotherapy in the others. Survival in general was less than 6 months after the diagnosis of brain metastases. The prognosis is poor once the onset of brain metastases is evident.

Skip metastasis in papillary thyroid carcinoma is difficult to predict in clinical practice

BACKGROUND

Cervical lymph node metastases are very common in papillary thyroid cancer (PTC), and typically spread in a predictable stepwise fashion in clinical practice. However, lateral lymph node metastasis (LLNM) without central lymph node metastasis (CLNM) as skip metastasis is not rare in PTC. The aim of this study was to investigate the incidence, risk factors and pattern of skip metastasis in PTC.

METHODS

A total of 271 patients with PTC and suspicious LLN diagnosed by pre-operation examinations who underwent total thyroidectomy and central lymph node dissection plus lateral lymph node dissection between January 2008 and December 2011 were enrolled in this study. Clinicopathological features were collected, and the pattern of cervical lymph node metastasis and skip metastasis were analyzed.

RESULTS

The LLNM rate was 74.9% (203/271, diagnosed by postoperative pathology examination) and significantly associated with extrathyroid extension (ETE), primary tumor located at the upper pole, and CLNM (p < 0.05). The skip metastasis rate was 14.8% (30/203) and was more frequently found in microcarcinoma patients, especially when the primary tumor size was ≤0.5 cm (p = 0.001 OR = 12.9). However, skip metastasis was unrelated to the remaining factors examined.

CONCLUSION

Small cancers with a pre-operation diagnosis of LLNM are more likely to have skip metastases, especially when the primary tumor size is less than 0.5 cm in diameter; however, this type of metastasis appears to develop in a random fashion. Thus, additional research is needed to identify potential predictive factors, such as a primary tumor located at the upper pole.

Response to Treatment is Highly Predictable in cN0 Patients with Papillary Thyroid Carcinoma

BACKGROUND

While involvement of macrometastatic lymph nodes is a recognized independent predictor of an adverse course in papillary thyroid cancer (PTC) patients, the clinicopathological variables associated with disease persistence/recurrence in clinically node-negative (cN0) disease are not well defined. The indications for prophylactic central neck dissection (pCND) in this patient group remain unclear as well. We aim to investigate the risk factors associated with short- and long-term persistence/recurrence of PTC in patients with cN0 disease at presentation compared to patients with PTC and cervical lymph node involvement (N1) and the response to initial treatment in these subgroups of patients.

METHODS

Data were collected retrospectively for 392 consecutive patients with PTC, 223 with cN0 disease and 169 with N1 disease, who were treated and followed at a single tertiary medical center in which pCND is not routinely performed for PTC.

RESULTS

Compared to patients with N1 disease, patients with cN0 disease had significantly smaller tumors, lower rates of multifocality, and less extrathyroidal extension. Persistency rates at 1 year were 6.7 % in the cN0 group and 47 % in the N1 group, and at last follow-up, 3.6 and 33.5 %, respectively (p = 0.001 for both time points). Within the cN0 group, those with persistent disease at 1 year (n = 15) had significantly larger tumors and higher stimulated thyroglobulin. Only six had structural residual disease, four of them lymph node metastases. All patients with persistent disease were initially treated with total thyroidectomy and radioiodine. Recurrence occurred in only three patients. After 8.3 ± 3.8 years of follow-up, eight patients with cN0 had persistent disease, three of them biochemical. Higher American Joint Committee of Cancer stage and extrathyroidal extension were the only factors that predicted disease persistence at the last follow-up in this group.

CONCLUSIONS

Patients with cN0 PTC and no distant metastases are usually disease free after thyroidectomy with/without radioactive iodine and do not need further interventions. The initial staging in these patients is a valid prognostic factor for disease outcomes.

Risk prediction in children and adults less than 45 years old with papillary thyroid cancer

The incidence of papillary thyroid cancer is increasing faster than any other cancer in young patients. The purpose of this review is to discuss the most recent determinants of risk of recurrence and compromised outcomes in this population. Areas covered: This review discusses the most updated data on patient age, including children and young adults, extent of disease and subsequent dynamic staging over time, molecular markers for disease aggressiveness, adequacy of surgical resection and surgeon volume, and novel therapies for advanced non-resectable disease as predictors of patient outcomes. Expert commentary: Young patients enjoy excellent outcomes, with long-term survivorship, but face higher risks of short-term complications and disease recurrence. Thoughtful evaluation of the extent of disease, tumor features associated with more aggressive behavior, the presence of locoregional or distant metastases, and an understanding of molecular changes in their tumors are important areas of consideration. High-volume surgeons should work collaboratively with endocrinologists, radiologists, and pathologists specializing in thyroid cancer to help patients achieve excellent outcomes. Emerging data challenging the status quo regarding the relative importance of patient age, tumor features, and dynamic risk-adjustment for overall prognosis of these patients will likely impact future care and staging systems.

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

OBJECTIVES

WDTC (papillary and follicular thyroid cancer) make up around 90% of all thyroid tumours. Overall, the prognosis in patients with WDTC is excellent. However, there are small cohorts of patients who experience a more aggressive form of disease which is often associated with certain poor prognostic factors. Identifying these patients at an early stage is imperative for guiding treatment decisions. With recent developments in this area we plan to discuss the current evidence surrounding prognostic markers.

METHODS

The literature regarding prognostic factors in WDTC was reviewed using an electronic database Medline - Pubmed. Using the MeSH search engine specific prognostic factors including age, size, grade, lymph node involvement, distant metastasis, extension/invasion, ethnic background, radioactive iodine avidity, and thyroglobulin level and their association with WDTC were evaluated. A broader search of prognostic markers in thyroid cancer was also carried out to avoid missing other pertinent markers.

RESULTS

Multiple clinical and pathologic variables have been shown to be poor prognostic factors in WDTC with statistical significance. Extensive extrathyroidal extension and age may be the most important factors when predicting clinical outcomes in WDTC, although the age threshold may be increased from 45 to 55 years in due course.

CONCLUSIONS

Management of WDTC has changed considerably over the last two years as reflected in evolving British and American Thyroid Guidelines. In all cases a combined multi-disciplinary approach, with consideration of the available guidelines and stratification systems should be utilised when planning an individualised treatment program to offer the best contemporary care to WDTC patients.

Evolution of the histologic classification of thyroid neoplasms and its impact on clinical management

The vast majority of low grade follicular cell derived thyroid carcinomas follows an indolent clinical course and is associated with very low mortality. Risk stratification using multiple clinical and pathologic characteristics has become the standard of care to guide appropriate management and avoid overtreatment. Over the past few decades, the field of thyroid pathology has witnessed several major changes that significantly impacted upon patients' care. These are: 1) The reclassification of non-invasive encapsulated follicular variant of papillary thyroid carcinoma as noninvasive follicular thyroid neoplasm with papillary-like nuclear features; 2) the diagnosis of Hurthle cell carcinoma based on the presence of capsular and vascular invasion; 3) a detailed definition of poorly differentiated thyroid carcinoma, taking into consideration mitosis and necrosis; and 4) the emphasis on a detailed pathologic analysis such as the extent of vascular invasion and extrathyroidal extension. This review describes these histological concepts and details the history, rationale, and clinical impacts of such changes. These shifts in the classification and characterization of thyroid carcinoma provided a platform supporting therapy de-escalation. In addition several lessons were learned from these changes especially from the misclassification of the non-invasive encapsulated follicular variant of papillary thyroid carcinoma. We hope that the lessons learned will help better classify tumors in the future whether arising in the thyroid or other organs.

Autoimmune thyroid diseases in children

Autoimmune thyroid diseases (AIT) are common in children and may present with a variety of signs and symptoms including: euthyroid goiter, hypothyroidism, or hyperthyroidism. The natural history of AIT may be different in children but in all age groups, there appear to be genetic risk factors and environmental triggers that initiate thyroid autoimmunity. Areas covered: In this review, we summarize recent studies that investigate the genetics and environmental triggers believed to be involved in thyroid autoimmunity. We also discuss the approach and controversies in the treatment of children with AIT. Expert commentary: Much has been learned about the major roles for genetics, cytokines, regulatory lymphocytes, and environmental triggers in CLT but controversies remain.

Surgical management of primary thyroid tumours

The majority of patients who present with well differentiated thyroid cancer will require surgery, but decisions on the appropriate primary procedure will depend on information relating to patient, tumour and surgical factors. As the incidence of thyroid cancer continues to rise, it is critical that clinicians involved in the management of these cases understand the factors which underpin surgical decision making for individual patients. Reporting outcomes in well differentiated thyroid cancer (WDTC) has always been challenging due to the low recurrence and mortality rate of the disease. Although early data supported total thyroidectomy for all patients with >1 cm WDTC, more recent evidence has supported lobectomy in selected, low risk patients. As a result we have seen a change in the approach of international guidelines from a blanket statement that total thyroidectomy should be the treatment for all patients towards a more selective approach to therapy. When selecting the most appropriate surgical approach to WDTC, the primary aim is to minimize the chance of death from disease or further recurrence. Additionally the impact of potential side effects of treatment (laryngeal nerve injury and hypocalcaemia) must also be weighed in the balance. In this review of surgical management of WDTC we aim to present a historical perspective on this subject and explore the arguments for and against total thyroidectomy and thyroid lobectomy in the low-risk patient group.

Prognostic impact of minimal extrathyroidal extension in papillary thyroid carcinoma

BACKGROUND

It is widely accepted that maximal extrathyroidal extension (ETE) plays a vital role in the prognosis of papillary thyroid carcinoma (PTC). However, there is no consensus among researchers about the meaning of minimal ETE (mETE) in PTC. Herein, we conducted a systematic review and meta-analysis to examine the role of mETE in the prognosis of PTC.

METHODS

We searched PubMed, EMBASE, and Cochrane search trials databases in English to identify studies comparing data on disease recurrence in PTC patients with mETE and those with no ETE. To summarize the data related to mETE status, risk ratios and hazard ratios adjusted for potential confounders were used to assess the number of recurrence and time-dependent risks related to mETE status, respectively.

RESULTS

According to the inclusion criteria, a total of 7951 patients from 9 studies were included. The recurrence rate in patients with mETE is significantly higher when compared with those with no ETE (risk ratio = 1.70, 95% confidence interval: 1.26-2.28, I = 56%). According to the data summarized with hazard ratios, PTC patients with mETE showed a significantly increased risk of disease recurrence.

CONCLUSION

mETE is a risk factor for poor prognosis in patients with PTC. Our innovative classification of ETE has its value in assessing the prognosis of PTC.