Thyroid cancer surgery guidelines in an era of de-escalation

Role of prophylactic central neck lymph node dissection for papillary thyroid carcinoma in the era of de-escalation

Thyroid cancer is the most common endocrine malignancy. While there has been no appreciable increase in the observed mortality of well-differentiated thyroid cancer, there has been an overall rise in its incidence worldwide over the last few decades. Patients with papillary thyroid carcinoma (PTC) and clinical evidence of central (cN1) and/or lateral lymph node metastases require total thyroidectomy plus central and/or lateral neck dissection as the initial surgical treatment. Nodal status in PTC patients plays a crucial role in the prognostic evaluation of the recurrence risk. The 2015 guidelines of the American Thyroid Association (ATA) have more accurately determined the indications for therapeutic central and lateral lymph node dissection. However, prophylactic central neck lymph node dissection (pCND) in negative lymph node (cN0) PTC patients is controversial, as the 2009 ATA guidelines recommended that CND "should be considered" routinely in patients who underwent total thyroidectomy for PTC. Although the current guidelines show clear indications for therapeutic CND, the role of pCND in cN0 patients with PTC is still debated. In small solitary papillary carcinoma (T1, T2), pCND is not recommended unless there are high-risk prediction factors for recurrence and diffuse nodal spread (extrathyroid extension, mutation in the BRAF gene). pCND can be considered in cN0 disease with advanced primary tumors (T3 or T4) or clinical lateral neck disease (cN1b) or for staging and treatment planning purposes. The role of the preoperative evaluation is fund-amental to minimizing the possible detrimental effect of overtreatment of the types of patients who are associated with low disease-related morbidity and mortality. On the other hand, it determines the choice of appropriate treatment and determines if close monitoring of patients at a higher risk is needed. Thus, pCND is currently recommended for T3 and T4 tumors but not for T1 and T2 tumors without high-risk prediction factors of recurrence.

The role of surgery in small differentiated thyroid cancer

INTRODUCTION

The incidence of small, differentiated thyroid cancer (DTC) cases has been increasing in the United States and the world mainly due to incidental detection because of widespread use of diagnostic modalities. While the option of active surveillance instead of surgical resection is getting more popular, there is still an open discussion about the best approach in these cases.

MATERIALS AND METHODS

The National Cancer Database was queried for patients diagnosed with non-metastatic small T1/N0 DTC between 2004 and 2016, who have known surgical status and Charlson comorbidity index of two or less. We evaluated the overall survival (OS) based on the surgery status using Kaplan-Meier estimates and multivariable cox regression analyses.

RESULTS

A total of 98,501 patients with non-metastatic small DTC were included, within which 96,612 (98.1%) were treated with surgery, and 1889 (1.9%) were not treated with surgery or other ablative modalities. We found that patients who were treated with surgery had better OS compared to patients who were not treated with surgery (mean OS 171 months vs 134.1 months, P < 0.001, median OS was not reached). This difference was still statistically significant even after we used propensity score matching for age, gender, race, Charlson-Deyo score, tumor size, and histology. On multivariate analysis, surgery was associated with better OS (HR 0.218; 95% CI: 0.196-0.244; P < 0.001). Same trend was found in subgroup analysis when we split the cohort according to tumor size (<1 and ≥1 cm), histology (follicular, papillary and Hurthle cell carcinoma), and age (<55 years vs ≥55 years).

CONCLUSION

Patients with non-metastatic small DTC who were treated with surgery had significant improvement in OS compared to patients who were not treated with surgery. Notwithstanding the limitations of the current analysis, these results call for caution prior to recommending routine surveillance for all patients with small DTC.

Novel Strategies for Managing Retropharyngeal Lymph Node Metastases in Head and Neck and Thyroid Cancer with Transoral Robotic Surgery (TORS)

Retropharyngeal metastases are encountered in a variety of head and neck malignancies, imposing significant surgical challenges owing to their distinct location and proximity to neurovascular structures. Radiotherapy is the recommended treatment in most cases owing to its oncological efficacy. However, retropharyngeal irradiation affects the superior pharyngeal constrictor muscles and parotid glands, with the potential for long-term dysphagia and xerostomia. A younger oropharyngeal and thyroid cancer patient demographic is trending, fueling interest in treatment de-escalation strategies. Consequently, reducing radiotoxicity and its long-term effects is of special relevance in modern head and neck oncology practice. Through its unique ability to safely extirpate these traditionally difficult-to-access retropharyngeal lymph nodes via a natural orifice, TransOral Robotic Surgery (TORS) can considerably lower the surgical morbidity of retropharyngeal lymph node dissection (RPLND), compared with current existing approaches. This review summarizes the latest developments in the field, exposing current research gaps and discusses specific clinical settings where TORS could enable treatment de-escalation. In early-stage node-negative oropharyngeal cancer, single-modality surgical treatment with TORS RPLND may improve risk stratification of metastasis and recurrence in this region. TORS RPLND is also a potentially viable treatment option in salvage of an isolated retropharyngeal node recurrence or in the primary setting of a thyroid malignancy with a single positive retropharyngeal node. In time, TORS RPLND may provide an alternative de-escalation strategy in these three scenarios. However, with the reported morbidities, further prospective trials with long-term follow-up data are required to prove oncological safety and functional benefits over existing strategies.

Biodegradable iron oxide nanoparticles for intraoperative parathyroid gland imaging in thyroidectomy

Parathyroid gland (PG) injury is the most common complication of thyroidectomy owing to the lack of approaches for surgeons to effectively distinguish PGs from surrounding thyroid glands (TGs) in the operation room. Herein, we report the development of biodegradable iron oxide nanoparticles (IONPs) as a promising contrast agent candidate for intraoperative PG visualization. We elucidated that locally administrated dark-colored IONPs readily diffuse in TGs but cannot infiltrate tissue-dense PGs, yielding a distinguishable contrast enhancement between PGs and TGs by naked eye observation. We performed unbiased and quantitative in vivo screenings to optimize particle size and concentration of IONPs for PG/TG contrast enhancement. Moreover, in vivo applications of IONPs via the local administration route demonstrate no adverse toxicities and can be biodegraded in the thyroid microenvironment within 3 months. To our knowledge, these promising findings provide the first in vivo evidence that IONPs can serve as a safe, biodegradable, and effective contrast agent candidate for improving PG visualization in thyroidectomy.

The 2015 American Thyroid Association guidelines and trends in hemithyroidectomy utilization for pediatric thyroid cancer

BACKGROUND

In 2015, the American Thyroid Association (ATA) released its inaugural recommendations for the management of thyroid cancer in children. We aim to evaluate whether there has been a change in hemithyroidectomy utilization for pediatric differentiated thyroid cancer, and the association between those changes and the release of the ATA guidelines.

METHODS

The National Cancer Database was queried and identified 4776 patients ≤18 years old with differentiated thyroid cancer. Causal impact time-series analysis and logistic analysis were utilized to assess factors associated with use of hemithyroidectomy.

RESULTS

Post-2015 hemithyroidectomy rate was greater than predicted based on preguideline trends (predicted: 8.4%, actual: 12.6%, p = 0.001). In logistic analysis of factors associated with hemithyroidectomy use, we find that Papillary histology, tumor size >1 cm, nodal examination, and positive nodes were associated with lower rate of hemithyroidectomy (OR: 0.23, 0.51, 0.62, and 0.18, respectively).

CONCLUSION

There has been a significant increase in hemithyroidectomy utilization for pediatric differentiated thyroid cancer.

Thyroid stimulating hormone suppression and recurrence after thyroid lobectomy for papillary thyroid carcinoma

BACKGROUND

Thyroid lobectomy is recommended as the primary treatment for low-risk thyroid cancer. However, recurrence and hypothyroidism may develop after lobectomy, necessitating thyroid hormone supplementation. The 2015 American Thyroid Association (ATA) guidelines recommended post-lobectomy thyroid-stimulating hormone (TSH) suppression. This study examined the need for TSH suppression and recurrence after lobectomy for unilateral papillary thyroid carcinoma (PTC).

METHODS

This study involved 369 patients who underwent thyroid lobectomy and ipsilateral central neck dissection for PTC between 2007 and 2015. Thyroid function tests were performed before and regularly after lobectomy. Binary logistic regression analyses were used to find factors predictive of the post-lobectomy need for TSH suppression that was defined by the 2015 ATA guidelines.

RESULTS

Serum TSH concentrations gradually increased after lobectomy: proportions with TSH >2 mIU/L at post-lobectomy 1, 3-6, 12, and 24 months were found in 77.0%, 82.3%, 66.7%, and 59.9%, respectively. After lobectomy, 168 (45.5%) patients received levothyroxine (T4) supplementation. Multivariate logistic regression analyses showed that pre-TSH level >2 mIU/L was the sole independent variable predictive of the need for post-lobectomy TSH suppression (P = 0.003). During the median follow-up of 72 months, recurrence was found in 4 (1.1%) patients who never received T4 supplementation and had post-lobectomy TSH levels >2 mIU/L.

CONCLUSIONS

Our data show that thyroid lobectomy for unilateral PTC is associated with a low recurrence rate, but a significant risk of hypothyroidism. Preoperative TSH level can predict the need for post-lobectomy TSH suppression compliant with the 2015 ATA guidelines.

Thyroidectomy for Papillary Thyroid Carcinoma

Papillary thyroid carcinoma is the most common endocrine malignancy and accounts for the overwhelming majority of thyroid carcinoma. This recent dramatic increase in incidence is almost exclusively attributed to the incidental detection of small papillary thyroid carcinoma or microcarcinoma. Surgical management of thyroid carcinoma has been evolving to avoid overtreating patients by adopting the appropriate risk-based approach including the recommendation of hemithyroidectomy for low-risk carcinoma, the avoidance of routine prophylactic central nodal dissections, a higher threshold in using postoperative radioiodine ablation after total thyroidectomy, and the active observation or surveillance of papillary microcarcinoma as a viable alternative option instead of immediate surgical treatment.

Lymph Node Dissection for Papillary Thyroid Carcinoma

Cervical lymph node metastasis is frequent in patients with papillary thyroid carcinoma. In addition to the extent of thyroidectomy, the need as well as the extent of concomitant lymphadenectomy has been a subject of controversy and debate. The central compartment is the most frequent site of metastasis followed by the lateral compartment although skip metastasis in the lateral compartment can occur. Papillary thyroid carcinoma can also present with cervical lymph node metastasis, while the primary tumor remains clinically undetectable. Surgical removal of clinically involved nodal metastasis should be mandatory to prevent recurrence and improve disease prognosis. However, despite a low accuracy of preoperative imaging for microscopic disease and the frequent microscopic metastasis to the central compartment, routine prophylactic neck dissection has not been shown to have any relevance to prevent recurrence or improve disease cure. Routine or prophylactic central compartment dissection is generally not recommended unless in the presence of high-risk tumors. The potential benefit of reducing central compartment recurrence or avoiding high-risk reoperation probably outweighs the risk of inducing surgical complication including hypoparathyroidism during routine central neck dissection. Therapeutic lateral neck dissection is performed for clinically involved nodes detected by preoperative imaging confirmed by needle biopsy, while prophylactic lateral neck dissection is contraindicated. The extent of neck dissection has been de-escalated, and compartmental nodal dissection aiming at preservation of function is performed to achieve a complete surgical resection. Postoperative adjuvant radioiodine is frequently administered for patients with positive nodal metastasis (intermediate-risk group) to avoid future recurrence. Routine central neck dissection may also upstage patients with microscopic nodal metastases and increase the use of postoperative adjuvant radioiodine.

Yield and costs of molecular diagnostics on thyroid cytology slides in the Netherlands, adapting the Bethesda classification

Objective

To evaluate our institutional experience with molecular diagnostics (MD) on thyroid cytology smears, evaluate the costs and describe MD guided clinical management of indeterminate Bethesda III/V thyroid nodules.

Methods

We performed a retrospective review of 164 Bethesda III or V thyroid cytopathology reports subjected to MD from 2013 to 2020, that altered Bethesda classification or management. MD consisted of mutation and gene fusion analysis by next‐generation sequencing (NGS) of morphologically analysed and selected cytological slides. Findings were modelled to nationwide data on Bethesda incidences from ‘the Dutch Pathology Registry’ PALGA, and costs were estimated.

Results

82 of 164 cases received an upgrade in Bethesda class. Twenty cases changed from Bethesda III to IV/V, 62 from Bethesda III or V to VI, and 72 remained unaltered. We estimate net savings with implementing MD, by preventing 454 repeat cytology and 326 (diagnostic) hemithyroidectomies, to be at least 2 million Euro annually in the Netherlands. Per Bethesda III and V patient, net savings would be about 100 Euro and 4100 Euro, respectively.

Conclusion

NGS‐based MD on nucleic acids extracted directly from cytology slides is a feasible and cost saving tool for personalized management in indeterminate Bethesda III/V thyroid cytology. Based on the interpretation of our retrospective data, we assume that this approach results in less disease burden for the patient, reduced surgical interventions and complication risks, reduced sick leave, among others. Further evaluation of structural implementation of the presented approach in routine thyroid Bethesda III/V cytology in a prospective setting is warranted.

Decline in radioiodine use but not total thyroidectomy in thyroid cancer patients treated in the United Arab Emirates - A retrospective study

Objectives

To assess the trend of clinicopathological features and treatment modalities in patients with thyroid cancer (TC) in the largest oncology center in the United Arab Emirates (UAE).

Methods

A retrospective analysis of patients with TC presenting to a tertiary care hospital in Al Ain, UAE between September 2008 and December 2018 identified using ICD 9 & 10 codes was performed. Data on demographics, histopathology, surgical extent, and use of Radioiodine (RAI) were extracted. Exact logistic and ordinal logistic regressions were performed to analyze the annual trend in features and management of TC, and logistic regression analysis was performed to identify predictors of total thyroidectomy and RAI use.

Results

A total of 762 patients were included in the analysis (mean age: 39.6 ± 12.6 years, 45 (60%) women). The majority (92.2%) were diagnosed with papillary thyroid cancer (PTC) and 83.9% had tumor size of <4 cm. All patients underwent surgery (93.8% total thyroidectomy, 6.2% lobectomy) and 77.4% received RAI therapy overall with a significant (p < 0.001) decline from 100% in 2008 to 60% in 2018. In multivariate analysis, nationality, and lymph node (LN) involvement were significant predictors of total thyroidectomy, while nationality, LNs, year of diagnosis, and tumor size significantly predicted RAI use.

Conclusion

Most patients in our cohort were diagnosed with localized PTC with no significant change in the extent of surgical approach but a substantial decline in RAI therapy administration over time. Nationality and LN involvement were significant predictors of surgical extent and RAI use.

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This is the largest study evaluating clinicopathological features and treatment modalities in TC patients in the UAE.

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Most patients were diagnosed with localized PTC.

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A substantial decline in RAI therapy administration but not the extent of thyroidectomy was observed during the study period.

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Nationality and LN involvement were significant predictors of surgical extent and RAI use.

Physician Confidence in Neck Ultrasonography for Surveillance of Differentiated Thyroid Cancer Recurrence

IMPORTANCE

Neck ultrasonography, a mainstay of long-term surveillance for recurrence of differentiated thyroid cancer (DTC), is routinely used by endocrinologists, general surgeons, and otolaryngologists; however, physician confidence in their ability to use ultrasonography to identify lymph nodes suggestive of cancer recurrence remains unknown.

OBJECTIVE

To evaluate physicians' posttreatment surveillance practices for DTC recurrence, specifically their use of and confidence in ultrasonography.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional study of 448 physicians in private and academic hospitals who completed a survey on DTC posttreatment practices from October 2018 to August 2019 (response rate, 69%) and self-reported involvement in long-term surveillance for thyroid cancer recurrence. Physicians were identified by patients affiliated with the Surveillance, Epidemiology, and End Results Program registries in Georgia State and Los Angeles County. Of the respondents, 320 physicians who reported involvement with DTC surveillance were included in the analysis.

MAIN OUTCOMES AND MEASURES

Physician-reported long-term surveillance practices for DTC, including frequency of use and level of confidence in ultrasonography for detecting lymph nodes suggestive of cancer recurrence.

RESULTS

In the cohort of 320 physicians who reported involvement with DTC surveillance, 186 (60%) had been in practice for 10 years to less than 30 years; 209 (68%) were White; and 212 (66%) were men. The physicians included 170 (56%) endocrinologists, 67 (21%) general surgeons, and 75 (23%) otolaryngologists. Just 84 (27%) physicians reported personally performing bedside ultrasonography. Only 57 (20%) had high confidence (rated quite or extremely confident) in their ability to use bedside ultrasonography to identify lymph nodes suggestive of recurrence; 94 (33%) did not report high confidence in either their ability or a radiologist's ability to use ultrasonography to detect recurrence. Higher confidence in ultrasonography was associated with the general surgery subspecialty (odds ratio [OR], 5.7; 95% CI, 2.2-14.4; reference endocrinology) and with treating a higher number of patients per year (>50 patients: OR, 14.4; 95% CI, 4.4-47.4; 31-50 patients: OR, 8.4; 95% CI, 2.6-26.7; 11-30 patients: OR, 4.3; 95% CI, 1.5-12.1; reference 0-10 patients).

CONCLUSIONS AND RELEVANCE

Given the importance of neck ultrasonography in long-term surveillance for thyroid cancer, these findings of physicians' low confidence in their own ability and that of radiologists to use ultrasonography to detect recurrence point to a major obstacle to standardizing long-term DTC surveillance practices.

Sternal metastatectomy in a case of papillary thyroid carcinoma

Thyroid cancer is the most common among endocrine cancers. Over 90% of all thyroid malignancies are differentiated thyroid carcinomas (DTC). However, only 2%-13% of DTC present with bone metastasis. Radioactive iodine ablation (RAI) is the treatment of choice for metastatic DTC. However, RAI therapy is not as effective in bone metastasis as it is in lung and visceral metastases. Only few cases of surgical management of bone metastasis in DTC have been reported in the literature. Here, we report a case of follicular variant of papillary thyroid carcinoma with sternal and lung metastases, for which sternal metastatectomy was performed.

Continuing controversy regarding individualized surgical decision-making for patients with 1-4 cm low-risk differentiated thyroid carcinoma: A systematic review

Implementing high-quality randomized controlled trials is difficult for patients with 1-4 cm low-risk differentiated thyroid carcinoma (DTC). Controversy exists regarding whether lobectomy (LT) or total thyroidectomy (TT) is the optimal surgical approach over the short term and long term. Inconsistent recommendations have led to confusion amongst surgeons. Consequently, the outcomes of patients may be influenced. A great deal of new literature is published monthly, and there have been numerous studies supporting both LT and TT. Surgeons must spend considerable time and energy clarifying why controversy exists and which studies should be used as references. We selected 19 recent guidelines/consensuses for surgical approach in treating of 1-4 cm DTC. This study presents various topics relevant to the present debate, including disease-specific survival (DSS), persistence/recurrence, and complications between LT and TT, in patients with 1-4 cm low-risk DTC. This review includes a discussion of the background of those recommendations with regard to various medical, cultural and geographic environments. Additionally, recent technologies and future directions for current issues in risk identification were integrated into the review to provide a reference for individualized decision-making for patients with 1-4 cm low-risk DTC. Given different national conditions, there are different points of emphasis amongst the guidelines. Consideration of surgical approach should consider the character of both surgeons and patients. We should balance the relative benefits, risks and resulting quality of life in order to perform individualized surgical decision-making, and to make reasonable decisions in employing either TT or LT.

New paradigms in the treatment of low-risk thyroid cancer

INTRODUCTION

Thyroid cancer is the most common endocrine malignancy. Multiple different staging systems have been introduced and used for differentiated thyroid carcinoma (DTC).

AREAS COVERED

In this literature review we provide an overview of the standard options for management of patients with low risk differentiated thyroid cancer.

EXPERT OPINION

Surgery is considered the first and most important step in managing DTC with goal to remove all the malignant foci in order to achieve cure and increase the survival with least chance of recurrence. Many studies have been conducted to determine the best surgical approaches and how aggressive surgeries should be in order to achieve the best outcomes regarding efficacy as well as safety. Radioactive iodine (RAI) therapy has also been a part of the treatment regimen and is used for different purposes with three main goals: post-surgical ablation, adjuvant therapy and persisted/recurrent disease treatment. Radiation therapy, on the other hand, is still not recommended to be used routinely in DTC because of the conflicting data of its benefit.

The Identification of Intraoperative Risk Factors Can Reduce, but Not Exclude, the Need for Completion Thyroidectomy in Low-Risk Papillary Thyroid Cancer Patients

Background: The extent of initial surgical resection for low-risk papillary thyroid cancer (PTC) remains debatable. Since the 2015 American Thyroid Association (ATA) guidelines, several retrospective studies have reported that 40-60% of patients initially treated with lobectomy would require a completion thyroidectomy (CTx) due to high-risk pathological features (HRFs). These studies are limited by variable preoperative stratification and inability to quantify the value of intraoperative assessment. The study objectives were to determine whether diligent preoperative and intraoperative assessment improves the appropriateness of initial surgery for low-risk PTCs and whether varying the criteria for lobectomy reduces the need for CTx. Methods: A prospectively collected province-wide database was analyzed over a 10-year period (2008-2017) for patients who underwent a total thyroidectomy (TT) for PTC without preoperative HRFs. All patients had preoperative ultrasound and fine-needle aspirates. Unique to this database are mandatory synoptic operative fields that identify intraoperative risk factors such as positive lymph nodes and local invasion. Results: In total, 74% of patients (709/959) were deemed eligible for lobectomy. Of those eligible, 149 (21%) had intraoperative risk factors that would necessitate conversion to TT at the initial operation. A further 209 (30%) would require CTx due to HRFs on final pathology. Varying the preoperative criteria for lobectomy did not significantly affect intraoperative conversion or CTx rates. Conclusions: Although intraoperative assessment reduced the need for CTx in 21%, up to 30% of patients would still require a second operation. Altering the preoperative criteria does not influence this outcome. Patients deemed eligible for lobectomy should be informed that despite careful pre- and intraoperative assessment, there is up to a 30% risk of requiring CTx.

Fine-Needle Aspiration of Subcentimeter Thyroid Nodules in the Real-World Management

BACKGROUND

The Korea Thyroid Association published the revised guidelines for thyroid nodules in 2016. However, whether fine-needle aspiration is accurately performed based on indications and whether the results of this procedure are appropriately addressed according to clinical guidelines, particularly in subcentimeter nodules, are unclear.

METHODS

We retrospectively analyzed the fine-needle aspiration data of 331 thyroid nodules of patients who were referred to a tertiary hospital clinic for fine-needle aspiration. Each nodule was categorized according to ultrasonography findings based on the recommendations of the Korea Thyroid Association for fine-needle aspiration. Only nodules with a final pathological diagnosis of benign or malignant made using the Bethesda system were included.

RESULTS

Up to 32% of thyroid nodules that were not indicated for fine-needle aspiration were aspirated. Regarding subcentimeter nodules, only 28 of 123 (22.8%) aspirated nodules were indicated for fine-needle aspiration. Of the 49 malignant subcentimeter nodules, 33 (67.3%) underwent immediate surgery. Meanwhile, 14 (28.6%) nodules were lost to follow-up, and two (4.1%) were under active surveillance. Eighteen (36.7%) malignant subcentimeter nodules were not indicated for fine-needle aspiration but underwent surgical resection instead of active surveillance.

CONCLUSION

Despite the recommendations in the revised guidelines, several thyroid nodules that do not meet the indications for FNA are aspirated in real-world practice. To reduce overtreatment, a widespread knowledge of the correct indications for fine-needle aspiration is important in clinical practice, particularly for subcentimeter nodules.

Quantifying the differences in surgical management of patients with definitive and indeterminate thyroid nodule cytology

INTRODUCTION

Thyroid nodules are increasingly common. Despite being an essential pre-operative diagnostic tool, up to 30% of fine needle aspirate cytology (FNAC) yields a non-definitive diagnosis. This study aimed to quantify differences in surgical management of patients with definitive and indeterminate thyroid nodule cytology, and determine if clinical factors can improve cytological diagnosis.

MATERIALS AND METHODS

Patients who underwent thyroidectomy for nodules from 2001 to 2015 were recruited. Those with benign and malignant preoperative cytology were included in the "definitive diagnosis" (DC) group; patients with all other preoperative cytology results were included in the "indeterminate diagnosis" (IC) group. We compared demographics and procedures between these groups. Clinical factors and demographics were also compared between patients with benign and malignant histology in the IC group.

RESULTS

A total of 3821 cases were included. A significantly larger proportion of the IC patients had a hemithyroidectomy (IC 69% vs. DC 39%, p < 0.001) initially, and also had a significantly higher rate of two-stage surgery compared to the DC group (IC 17% vs. DC 11%, p < 0.001). Patients in the DC group were twice as likely to undergo concurrent central lymph node dissection for papillary and medullary cancers than the IC group (p < 0.001). Overall, up to 60% of IC patients had been over- or under-treated at initial surgery. The clinical factors examined were not significantly associated with higher risk of malignancy in IC patients.

CONCLUSION

This study highlights the potential for improved preoperative diagnosis to streamline decision making for surgical management of patients with thyroid nodules.

Explaining the Variation in Surgical Practice for Differentiated Thyroid Cancer in Ontario, Canada

IMPORTANCE

In the management of differentiated thyroid cancer (DTC), the extent of surgical treatment required for most patients remains controversial and varies widely. This variation may be associated with the Enthusiasm Hypothesis, the notion that geographic differences in use of health care services are driven by the prevalence of physicians with a preference for particular services.

OBJECTIVE

To evaluate the Enthusiasm Hypothesis and its applicability to the variation in the surgical treatment of thyroid cancer in Ontario, Canada.

DESIGN, SETTING, AND PARTICIPANTS

This population-based study obtained electronic data on all health care-associated events for the complete population of insured residents of Ontario, Canada. Patients (n = 28 754) who were 18 years of age or older and underwent an initial therapeutic thyroid surgical procedure for a papillary or follicular carcinoma diagnosis between January 1, 2000, and December 31, 2015, were included. The final data analysis was performed January 31, 2019.

EXPOSURES

Therapeutic thyroid cancer surgical procedure.

MAIN OUTCOMES AND MEASURES

Numbers of surgeons, extent of surgical treatment, and case volumes in 14 geographic regions in Ontario.

RESULTS

In total, 28 754 patients with DTC were included, of whom 22 600 (78.6%) were female, with a mean (SD) age of 49 (14) years. The use of total thyroidectomy for DTC varied widely across geographic regions of Ontario, from 45.8% to 77.1% of all cancer cases. More than 90% of the overall variation in practice (total thyroidectomy vs less-than-total thyroidectomy) could be explained by the practices of the high-volume surgeons (enthusiasts) in regions with the highest rates of thyroid cancer diagnosis.

CONCLUSIONS AND RELEVANCE

The Enthusiasm Hypothesis appears to be consistent with the findings of this study. The practices of the high-volume surgeons who were enthusiastic for total thyroidectomy in the geographic regions with the highest rates of thyroid cancer diagnosis may account for the variation in practice across Ontario between 2000 and 2015.

IGSF1: A novel oncogene regulates the thyroid cancer progression

Thyroid cancer has been continuously increasing and extraordinarily prevalent worldwide. The genetic diagnosis has been widely used in fine needle aspiration. IGSF1, an immunoglobulin superfamily member 1, has been shown to be associated with the regulation of thyroid hormone. But the function of IGSF1 in thyroid cancer has not been explored yet. In this article, we will illuminate the correlation between IGSF1 expression and thyroid cancer. We analysed the level of IGSF1 expression in 55 pairs of tissue samples by real-time polymerase chain reaction (PCR) and The Cancer Genome Atlas (TCGA) data portal. After that, we transfected small interfering RNA to silence IGSF1 in thyroid cancer cell lines (KTC-1 and BCPAP) and confirmed the function of IGSF1 by performed colony formation, migration, invasion, cell counting kit-8, and apoptosis assays. IGSF1 was upregulated in thyroid cancer tissues compared with the adjacent normal tissues (t = 5.783, df = 54; P < .0001) and TCGA (T: N = 65.91 ± 3.998, n = 501: 2.824 ± 0.273, n = 58; P < .0001). In thyroid cell lines, experiments showed that downregulated IGSF1 inhibited proliferation, metastasis, and promoted cell apoptosis. Meanwhile, inhibited IGSF1 expression could downregulate N-cadherin, vimentin, and EZH2, which is associated with metastasis. Thyroid cancer cells IGSF1 expression levels are a correlation with its ability to growth, metastasis, and apoptosis.

Multifocality of papillary thyroid carcinoma as a risk factor for disease recurrence

OBJECTIVES

Tumor multifocality or bilaterality is associated with increased risk of papillary thyroid carcinoma (PTC) recurrence. However, its prognostic value in clinical outcomes remains controversial. This study aimed to evaluate the association of multifocality or bilaterality with recurrence and survival after total thyroidectomy.

METHODS

This was a retrospective study of 2390 consecutive patients with pathologically confirmed PTC who underwent total thyroidectomy. Multifocality and bilaterality were decided based on the final pathology results, that is, if there were two or more tumor foci and bilateral location, respectively. Primary outcomes were recurrence-free survival (RFS). Cox proportional hazards regression analyses were used to assess the associations of multifocality, bilaterality, and other clinicopathological factors with RFS.

RESULTS

Multifocal and bilateral PTC were found in 892 (37.3%) and 593 (24.8%) patients, respectively. Multivariate analyses showed that multifocality, lymphovascular invasion, N category, and number of positive lymph node (>5) were significant independent variables predictive of RFS (all P < 0.05). Multifocality was associated with adjusted hazard ratios for RFS of 1.93 (95% confidence interval = 1.33-2.80; P = 0.001). In a subset analysis, the prognostic value of multifocality was found to be significant in those patients with PTC > 1 cm, but not in papillary thyroid microcarcinoma.

CONCLUSIONS

Tumor multifocality is an independent risk factor of PTC recurrence after total thyroidectomy. This indicate a more progressive state of disease, being included in risk stratification.

The 2015 American Thyroid Association guidelines are associated with an increasing rate of hemithyroidectomy for thyroid cancer

BACKGROUND

In an attempt to prevent overly aggressive treatment of low-risk thyroid cancers, the American Thyroid Association changed guideline recommendations in late 2015 to state that either hemithyroidectomy or total thyroidectomy are acceptable operations for these patients. We hypothesized that surgeons would increasingly perform hemithyroidectomy after the release of these guidelines.

METHODS

The database of the National Surgery Quality Improvement Program was queried to identify all patients with thyroid cancer who were undergoing thyroidectomy between 2009 and 2017. Patients treated before the release of the 2015 American Thyroid Association guidelines were compared with those treated afterward. Temporal trends in operative rates were assessed quarterly using interrupted time series analyses.

RESULTS

A total of 35,291 patients were included in the study. Of those, 26,882 (76.2%) were female and 25,193 (71.3%) were white. After the release of the American Thyroid Association guidelines, there was an increase in hemithyroidectomy rate for patients with cancer from 17.3% to 22.0% (P < .001). Interrupted time series analysis controlling for patient factors demonstrated that quarterly growth in the hemithyroidectomy rate accelerated almost 10-fold (P < .001) after publication of the revised guidelines. Of note, there was no corresponding increase in the completion thyroidectomy rate (8.3% versus 7.9%, respectively, P = .213). Patients treated with hemithyroidectomy were more likely to be managed as outpatients (70.8% versus 57.1%, P < .001), had fewer surgical site infections (0.3% versus 0.5%, P = .050), and had fewer unplanned reintubations (0.2% versus 0.4%, P = .005).

CONCLUSION

In hospitals participating in the National Surgery Quality Improvement Program, the hemithyroidectomy rate increased significantly after the release of the 2015 American Thyroid Association guidelines. Surgeons at hospitals that participate in the National Surgery Quality Improvement Program may be changing practice patterns in response to these guidelines.

Feasibility of using colloidal gold immunochromatography for point-of-care identification of parathyroid glands during thyroidectomy

AIM

To determine the feasibility of using colloidal gold immunochromatography for rapid identification of parathyroid glands during thyroidectomy.

MATERIAL AND METHODS

127 patients undergoing thyroidectomy were randomly divided into PTH-ICGT group (64 cases) and conventional naked eye group (63 cases). The rate of identification of parathyroid glands and the incidence of hypoparathyroidism were compared between the two groups.

RESULTS

PTH-CGI assay results showed that PTH concentration in the parathyroid tissue was (955.3 ± 16.1) ng/L; skeletal muscle tissue [(14.5 ± 1.5) ng/L], thyroid tissue [(15.0 ± 1.3) ng/L], adipose tissue [(15.3 ± 1.2) ng/L], lymph node tissue [(14.0 ± 1.2) ng/L];PTH levels in parathyroid tissues were compared with PTH levels in skeletal muscle, thyroid, fat, and lymph node tissues, respectively. The differences were statistically significant(t values were 23.62, 33.42, 39.34, 30.77, P < 0.0001, respectively); Among the 127 patients undergoing total thyroidectomy, the rate of detection of parathyroid glands was 92.7% in the conventional naked eye group and 96.4% in the PTH-ICGT group. There was no significant difference in the detection rate of parathyroid gland between the two groups (χ2 = 0.7067, P = 0.40). The incidence of temporary hypoparathyroidism after surgery in both groups was 11.3% and 5.7%, respectively (χ2 = 1.093, P > 0.05). The incidence of postoperative permanent hypoparathyroidism in both groups was 3.8% and 0, respectively (Fisher's exact test, P = 0.495).

CONCLUSION

PTH-CGI has a high efficiency in identifying parathyroid glands, which may increase the rate of clinical parathyroid detection and reduce the incidence of postoperative hypoparathyroidism.

Partial resection and reconstruction of the sternum for treatment of metachronous sternal metastasis of thyroid carcinoma: A case report

RATIONALE

Metachronous sternal metastasis of thyroid carcinoma was a rare disease. There was no consensus in the treatment for bone metastasis after the initial thyroid carcinoma surgery.

PATIENT CONCERNS

A 53-year-old female patient was hospitalized due to recurrent dull chest pains, with a history of radical right side thyroid carcinoma 4 years ago. On examination, there was an irregular mass on the lower left half of the sternum. Computerized tomography scan showed sternal bone destruction with a soft tissue mass.

DIAGNOSES

Metachronous sternal metastasis of thyroid carcinoma.

INTERVENTIONS

Partial resection of the sternum and reconstruction with a titanium alloy mesh were performed.

OUTCOMES

After a 3-year follow-up, the patient had no recurrence.

LESSONS

Surgical resection may be a sufficient treatment for metachronous sternal metastasis of thyroid carcinoma. Biosynthesis material mesh is preferred to be used.