Active Surveillance of Papillary Thyroid Cancer: Frequency and Time Course of the Six Most Common Tumor Volume Kinetic Patterns

The 2024 revised clinical guidelines on the management of thyroid tumors by the Japan Association of Endocrine Surgery

The Japan Association of Endocrine Surgery published the first edition of the "Clinical guidelines on the management of thyroid tumors" in 2010 and the revised edition in 2018. The guideline presented herein is the English translation of the revised third edition, issued in 2024. The aim is to enhance health outcomes for patients suffering from thyroid tumors by facilitating evidence-based shared decision-making between healthcare providers and patients, as well as standardizing the management of thyroid tumors. The focus is on adult patients with thyroid tumors, addressing clinically significant issues categorized into areas such as an overview of the diagnosis and treatment of thyroid nodules, treatment strategies by histological type, radioactive iodine therapy, treatment of advanced differentiated carcinoma, pharmacotherapy, and complications and safety management associated with thyroid surgery. Thirty-two clinical questions were established in these areas. Following a comprehensive search of the literature and systematic review to evaluate the overall evidence, we aimed to present optimal recommendations by considering the balance of benefits and harms from the patient's perspective. We integrated evidence and clinical experience to determine the "Certainty of evidence" and "Strength of recommendations". Based on these, we illustrated overall flows of care as "Clinical algorithms". Necessary background knowledge of diseases and established clinical procedures for understanding the recommendations are presented in "Notes", while information that may be clinically useful but for which evidence remains insufficient is included in "Columns", based on the current state of evidence. Finally, future challenges for the next revision are presented as "Future research questions".

Optimizing Face Validity and Clinical Relevance of a Mathematical Population Cancer Epidemiology Model Using a Novel Advisory Group Approach

BackgroundCancer simulation models can answer research and policy questions when prospective evidence is incomplete or not feasible. However, such models require incorporating unmeasureable inputs for which there is often not strong evidence, and model utility is limited if assumptions lack face validity or if the model is not clinically relevant. We systematically incorporated formal advisory input to mitigate these challenges as we developed a microsimulation model of papillary thyroid cancer (PApillary Thyroid CArcinoma Microsimulation model [PATCAM]).MethodsWe used a participatory action research approach incorporating focus group techniques and using principles of bidirectional learning.ResultsWe assembled a formal standing advisory group with representation by perspective (medical, patient, and payor), geography, and local practice culture to understand current and historical clinical beliefs and practices about thyroid cancer diagnosis and treatment. The group provided input on critical modeling assumptions and decisions: 1) the role of nodule size in biopsy decisions, 2) trends in provider biopsy behavior, 3) specialty propensity to biopsy, 4) population prevalence of thyroid cancer over time, 5) proportion of malignant tumors showing regression, and 6) cancer epidemiology and diagnostic practices by sex and age. Advisory group questions and concerns about model development will inform future research questions and strategies to communicate and disseminate model results.ConclusionsWe successfully used our advisory group to provide critical inputs on unmeasurable assumptions, increasing the face validity of our model. The use of a standing advisory group improved model transparency and contributed to future research plans and dissemination of model results so they can have maximum impact when guiding clinical decisions and policy.HighlightsUnfamiliarity with simulation modeling poses a threat to its acceptability and adoption. The effectiveness of these models is contingent on end-users' willingness to accept and adopt model results. The effectiveness of the models is further limited if they lack face validity to potential users or do not have clinical relevance.Several approaches to overcoming validity challenges have been advanced, such as collaborative modeling, which involves developing multiple models independently using common data sources. However, when only a single model exists, another approach is needed. We used an Advisory Group and "participatory modeling," which has been used in other settings but has not been previously reported in cancer modeling. We describe the methods used for and results of incorporating a formal advisory group into the development of a cancer microsimulation model.The use of a formal, standing advisory group (as opposed to one-off focus groups or interviews) strengthened our model by rigorously vetting modeling assumptions and model inputs with subject matter experts. The formal, ongoing structure promoted transparency. The group education in cancer modeling improved participant ability to provide useful input and may help with dissemination. The advisory group also provided critical feedback about how to effectively communicate model results and informed planned future research questions.

Outcomes and effectiveness of active surveillance for low-risk papillary thyroid carcinoma: a systematic review and meta-analysis

PURPOSE

This study aimed to evaluate the outcomes and effectiveness of active surveillance (AS) in patients with low-risk papillary thyroid carcinoma (PTC) and compare them to those of immediate surgery (IS).

METHODS

A systematic review and meta-analysis, including 14 comparative studies and 7 noncomparative studies, was conducted, encompassing a total of 9,397 patients.

RESULTS

AS was associated with lower rates of familial history of thyroid cancer, multiplicity, and overall mortality compared to IS. The disease progression rate during AS was 14.53% (95% CI, 9.59-21.43%), and the delayed surgery rate was 14.91% (95% CI, 8.35-25.21%). No thyroid cancer-related mortality was observed in either the AS and IS groups. Clinicopathological characteristics showed no significant differences between delayed surgery and IS, except for higher rates of extrathyroidal extension and multiplicity in the delayed surgery group. Overall complication and recurrence rates were higher in the delayed surgery group than in the IS group. Quality of life and anxiety levels were similar between AS and IS, except for interest in sex, where AS was more beneficial.

CONCLUSION

AS is a feasible and reliable option for managing low-risk PTC, with a relatively low rate of disease progression and no thyroid cancer-related mortality. However, AS should be undertaken with caution, given the higher rates of overall complications and recurrence in the delayed surgery group compared to the IS group. Further studies with larger sample sizes and long-term follow-up are needed to clarify the role and effectiveness of AS.

Molecular Profiling of Low-Risk Papillary Thyroid Carcinoma (mPTC) on Active Surveillance

CONTEXT

The active surveillance (AS) program for papillary thyroid carcinoma (≤1 cm) at low risk (mPTC) showed a low percentage of progression.

OBJECTIVE

The aim of this study was to find a molecular signature of cases that showed disease progression during AS, which would allow their early identification.

METHODS

We performed next-generation sequencing of 95 fine-needle aspiration cytology specimens from cases prospectively enrolled in the AS program to analyze key somatic driver alterations or gene fusions implicated in PTC tumorigenesis. TERT promoter analysis was performed using Sanger sequencing or droplet digital polymerase chain reaction.

RESULTS

BRAF p.V600E was found in 66.3% (63/95) of mPTC and was the most common somatic alteration, followed by RAS oncogene mutations detected in 3.2% of mPTC (3/95: 2 NRAS and 1 KRAS) and gene fusions detected in 3.2% of mPTC (3/95: 1 RET-PTC1, 1 TFG-NTRK1, 1 ALK imbalance). No TERT promoter mutations (C228T and C250T) were found in the analyzed mPTC (84/95). The comparison between the molecular profile and the clinical outcome of the mPTC (stable vs progressive disease) showed no correlation (P = .6) and did not identify a molecular signature able to identify progressive mPTC.

CONCLUSION

The molecular profile of mPTC is like that of bigger PTC with the exception that none of them showed a TERT promoter mutation. The identification of the most common driver mutations, such as BRAF, RAS, or gene fusions, is not helpful for the early identification of mPTC that will show disease progression during follow-up in the AS program.

Changes in the Volume and Diameter of Benign Thyroid Nodules: A 10-Year Follow-Up Study

Background: The incidence of asymptomatic thyroid nodules has risen enormously, with > 90% being benign. Despite limited long-term data, significant nodule growth (SNG) is common. Guidelines recommend cytology reevaluation if SNG occurs. Our study aimed to identify the rate and factors associated with SNG, compare diameter and volume-based assessments, and examine the association between SNG and malignancy risk over the long term (10 years). Methods: The retrospective cohort study, conducted at Ankara University, School of Medicine, Department of Endocrinology and Metabolism, included 732 nodules from 376 euthyroid patients, all monitored over a 10-year period by the same experienced sonographer, with evaluations at baseline, 5th and 10th years. The nodules were cytologically benign and/or sonographically in the low-to-intermediate risk category. Size changes at the 5th and 10th years were considered significant if there was a 20% or 2 mm increment in two diameters according to diameter-based criterion (DBC) or 50% increment in volume-based criterion (VBC) designed by the ellipsoid formula. Generalized linear mixed-effects models were used to account for the clustered data structure and analyze factors affecting nodule growth. Nodule growth was the dependent variable, while sex, age at diagnosis, initial TSH level, total nodule count, nodule volume, echogenicity, and localization were independent variables. Results: At the 5th and 10th years, SNG frequencies were higher when calculated using VBC [27.7% (n = 203) and 44% (n = 321), respectively] compared with DBC [19.1% (n = 140) and 35% (n = 256), respectively], with the differences being statistically significant (McNemar test, p < 0.01). Factors associated with SNG included being younger than 45 years of age (VBC OR = 1.704, CI = 1.227-2.366, p = 0.002; DBC OR = 1.913, CI = 1.379-2.656, p < 0.001), having higher number of nodules (VBC: OR = 1.171, CI = 1.061-1.291, p = 0.002; DBC: OR = 1.147, CI = 1.040-1.265, p = 0.006), and having smaller nodule volume (VBC: OR = 0.870, CI = 0.806-0.940, p < 0.001; DBC: OR = 0.912, CI = 0.850-0.978, p = 0.010). Thyroid cancer was diagnosed in four original nodules (0.5%), whereas the malignancy rate in biopsies performed was 1.4% (n = 4). Conclusions: In long-term follow-ups of sonographically and/or cytologically benign thyroid nodules, SNG is not rare. Growth is more likely in younger patients, those with higher number of nodules and smaller nodules. In the follow-up of nodule size, VBCs yield augmented results compared with DBCs. However, malignancy is quite rare in growing nodules. Therefore, adopting flexible long-term follow-up protocols appears to be practical for benign nodular thyroid disease.

Long-term outcomes of active surveillance for low-risk papillary thyroid carcinoma: Progression patterns and tumor calcification

INTRODUCTION

Active surveillance (AS) for low-risk papillary thyroid carcinoma (PTC) is acknowledged as a valid management strategy. While older age is identified as a favorable factor for progression, long-term evidence is scarce and lifelong monitoring has been deemed essential. This study investigated progression patterns and tumor calcification under long-term AS and explored the possibility of ending follow-up.

MATERIALS AND METHODS

A total of 650 patients with low-risk PTC who chose AS were enrolled. Progression was defined as either tumor enlargement (≥3 mm from initiation) or development of clinically apparent lymph node metastasis.

RESULTS

The median observation period was 8 years; 45.2% were under surveillance for ≥10 years. Overall, 80 patients (12.3%) exhibited progression. Median age and observation period at the time of progression were 55 and 4 years, respectively. Only 2 patients showed progression after 15 years of follow-up and 5 patients showed progression after reaching 80 years old. Among 71 patients experiencing tumor enlargement, surgery was performed immediately in 32 patients. The remaining 39 patients continued surveillance, but only 5 demonstrated ongoing enlargement thereafter. Of 40 surgeries due to progression, 36 were conducted within the first 10 years. The degree of calcification correlated with age and observation periods. No progression occurred after the development of rim calcification.

CONCLUSIONS

Progression during AS was extremely rare in older patients with long-term surveillance and in tumors with rim calcification. It may be feasible to consider ending scheduled surveillance visits for these patients. Instances of progression halting after enlargement are not uncommon.

Is conservative treatment always safe in unifocal clinically T1a/node-negative papillary thyroid carcinoma?

BACKGROUND

Management of clinically unifocal node-negative papillary thyroid carcinoma ≤1 cm (PTMC) is controversial with nonsurgical treatment as a potential alternative to thyroid lobectomy (TL). However, conservative strategies, such as active surveillance or thermal ablation, do not allow the evaluation of biological aggressive features or occult lymph node metastases (LNMs), which play a primary role as prognostic factors.

METHODS

Among 4216 thyroidectomies for malignancy (between September 2014 and September 2023), TL plus ipsilateral central neck dissection was performed in 203 (4.8%) unifocal N0 PTMCs. Completion thyroidectomy was accomplished in case of positive frozen section examination of removed nodes or within 6 months from index operation in presence of biological aggressive features.

RESULTS

Seventy-six out of 203 (37.4%) patients were staged pN1a and extranodal extension was detected in 5 (6.6%) patients. At final histology, biological aggressive features, including multifocality, lymphovascular invasion (LVI), extracapsular invasion, tumor aggressive subtypes, and BRAF-V600E mutation, were detected in 69 (34%), 93 (45.8%), 3 (1.5%), 30 (14.8%), and 7 (3.5%) patients, respectively. A comparative analysis between pN0 and pN1a patients showed younger age (p < 0.001), LVI (p = 0.037), and multifocality (p < 0.001) as risk factors for occult central LNMs. After logistic regression analysis, age (p < 0.001) and multifocality (p < 0.001) were confirmed as independent risk factors for nodal involvement.

CONCLUSIONS

Although most PTMC has been widely defined as indolent disease, a non-negligible rate of patients may present one or more biologically aggressive features including nodal involvement. Nonsurgical management should be considered with caution to avoid undertreatment especially in the younger population.

Outcomes of Conversion Surgery for Patients With Low-Risk Papillary Thyroid Carcinoma

Importance

The outcomes of patients with low-risk thyroid cancer who undergo surgery following a period of active surveillance (AS) are not well-defined.

Objective

To evaluate surgical, pathologic, and oncologic outcomes among patients undergoing conversion surgery (CS) following AS for low-risk papillary thyroid carcinoma.

Design, Setting, and Participants

In this cohort study, patients who underwent CS for disease progression were compared with patients who underwent CS without disease progression and with a propensity score-matched cohort of patients who underwent initial surgery (IS). The median (IQR) postsurgical follow-up time was 40.3 (18.0-59.0) months. Patients were treated at a quaternary cancer referral center in the United States.

Exposures

Surgery.

Main Outcomes and Measures

Surgical complications, pathologic characteristics, overall survival (OS), and recurrence-free survival (RFS).

Results

Of 550 patients who underwent AS, 55 (10.0%) had CS, of whom 39 (7.1%) had surgery due to suspected disease progression (median [IQR] age, 48 [39-56] years; 32 [82.1%] female). There were no clinically meaningful differences in rates of surgical sequalae between the progression CS group (12 of 39 [30.7%]) and the nonprogression CS group (7 of 16 [43.8%]) (Cramer V, 0.2; 95% CI, 0.01-0.5). The 5-year OS was 100% (95% CI, 100%-100%) in both the disease-progression CS cohort and the IS cohort. Although the cohort of patients undergoing CS after disease progression was by definition a subset with more aggressive tumor behavior, no clinically meaningful differences were observed in the rates of regional recurrence (2 of 39 [5.1%] vs 0 of 39 patients with IS), local recurrence (0 patients), distant metastasis (0 patients), or disease-specific mortality (0 patients) when compared with the matched IS group. Five-year RFS rates were similar: 100% in the IS group and 86% (95% CI, 70%-100%) in the CS group.

Conclusions and Relevance

In this cohort study, CS for suspected disease progression was associated with surgical and oncologic outcomes similar to IS, supporting the feasibility and safety of AS for patients with low-risk papillary thyroid carcinoma.

Active Surveillance in Early Thyroid Cancer: A Meta-Analysis

Background/Objectives: There remain several challenges to the acceptance and standardization of active surveillance (AS) in patients with early thyroid cancer. The purpose of this study was to update the evidence of tumor progression outcomes in AS to support resolution of clinical concerns and to examine the effect of follow-up duration, period context such as diagnostic techniques, and tumor size at baseline on outcomes. Methods: PubMed, Web of Science, and Embase were used to search for original articles in English until January 2024. The main outcomes were the pooled proportion of patients who showed tumor growth ≥ 3 mm, metastasis to cervical lymph nodes, and conversion to delayed thyroid surgery. A single-arm meta-analysis was performed using a random-effects model. Results: Fourteen studies with 7291 patients were included in the analysis. Pooled results showed that 5.6% (95% CI: 4.2-7.4) of patients increased tumor diameter by more than 3 mm, 1.1% (95% CI: 0.9-1.4) developed cervical lymph node metastases by clinical diagnosis and 3.6% (95% CI: 3.1-4.2) by pathology, 12.7% (95% CI: 9.9-16.1) of patients converted to delayed surgery, with 31.6% (95% CI: 25.3-38.7) of those conversions being due to tumor progression. Subgroup analysis showed a small difference in the proportion of outcomes by baseline tumor size but no increase in the proportion of tumor progression or conversion to surgery due to other factors. Conclusions: This meta-analysis suggests long-term stability in the proportion of tumor progression in AS and less susceptibility to external influences.

Standardized Ultrasound Evaluation for Active Surveillance of Low-Risk Thyroid Microcarcinoma in Adults: 2024 Korean Society of Thyroid Radiology Consensus Statement

Active surveillance (AS) has been widely adopted as an alternative to immediate surgery owing to the indolent nature and favorable outcomes of papillary thyroid microcarcinoma (PTMC). AS is generally recommended for tumors measuring ≤1 cm without aggressive cytological subtypes, risk of gross extrathyroidal extension (ETE), lymph node metastasis (LNM), or distant metastasis. AS requires careful patient selection based on various patient and tumor characteristics, and ultrasound (US) findings. Moreover, during AS, regular US is performed to monitor any signs of tumor progression, including tumor growth, new US features of potential gross ETE, and LNM. Therefore, appropriate imaging-based assessment plays a crucial role in determining whether AS or surgery should be pursued. However, detailed recommendations concerning US evaluation are currently insufficient, necessitating the formulation of this guideline. The Korean Society of Thyroid Radiology has developed a consensus statement for low-risk PTMC, covering US assessment methods when considering AS as a management option and conducting follow-up imaging tests during AS. This guideline aims to provide optimal scientific evidence and expert opinion consensus regarding a standardized US-based assessment protocol for low-risk PTMC.

Assessment of the Diagnostic Performance of a Commercially Available Artificial Intelligence Algorithm for Risk Stratification of Thyroid Nodules on Ultrasound

Background: Thyroid nodules are challenging to accurately characterize on ultrasound (US), though the emergence of risk stratification systems and more recently artificial intelligence (AI) algorithms has improved nodule classification. The purpose of this study was to evaluate the performance of a recent Food and Drug Administration (FDA)-cleared AI tool for detection of malignancy in thyroid nodules on US. Methods: One year of consecutive thyroid US with ≥1 nodule from Duke University Hospital and its affiliate community hospital (649 nodules from 347 patients) were retrospectively evaluated. Included nodules had ground truth diagnoses by surgical pathology, fine needle aspiration (FNA), or three-year follow-up US showing stability. An FDA-cleared AI tool (Koios DS Thyroid) analyzed each nodule to generate (i) American College of Radiology Thyroid Imaging Reporting and Data System (ACR TI-RADS) descriptors, scores, and follow-up recommendations and (ii) an AI-adapter score to further adjust risk assessments and recommendations. Four groups were then compared: (i) Koios with AI-adapter, (ii) Koios without AI-adapter, (iii) clinical radiology report, and (iv) radiology report combined with AI-adapter. Performance of the final recommendations (FNA or no FNA) was determined based on ground truth, and comparison between the four groups was made using sensitivity, specificity, and receiver-operating-curve analysis. Results: Of 649 nodules, 32 were malignant and 617 were benign. Performance of Koios with AI-adapter enabled was similar to radiologists (area under the curve [AUC] 0.70 for both, [CI 0.60-0.81] and [0.60-0.79], respectively). Koios with AI-adapter had improved specificity compared to radiologists (0.63 [CI: 0.59-0.67] versus 0.43 [CI: 0.38-0.48]) but decreased sensitivity (0.69 [CI: 0.50-0.83) versus 0.81 [CI: 0.61, 0.92]). Highest performance was seen when the radiology interpretation was combined with the AI-adapter (AUC 0.76, [CI: 0.67-0.85]). Combined with the AI-adapter, radiologist specificity improved from 0.43 ([CI: 0.38-0.48]) to 0.53 ([CI: 0.49-0.58]) (McNemar's test p < 0.001), resulting in 17% fewer FNA recommendations, with unchanged sensitivity (0.81, p = 1). Conclusion: Koios DS demonstrated standalone performance similar to radiologists, though with lower sensitivity and higher specificity. Performance was best when radiologist interpretations were combined with the AI-adapter component, with improved specificity and reduced unnecessary FNA recommendations.

Standardized Ultrasound Evaluation for Active Surveillance of Low-Risk Thyroid Microcarcinoma in Adults: 2024 Korean Society of Thyroid Radiology Consensus Statement

Active surveillance (AS) has been widely adopted as an alternative to immediate surgery owing to the indolent nature and favorable outcomes of papillary thyroid microcarcinoma (PTMC). AS is generally recommended for tumors measuring ≤1 cm without aggressive cytological subtypes, risk of gross extrathyroidal extension (ETE), lymph node metastasis (LNM), or distant metastasis. AS requires careful patient selection based on various patient and tumor characteristics, and ultrasound (US) findings. Moreover, during AS, regular US is performed to monitor any signs of tumor progression, including tumor growth, new US features of potential gross ETE, and LNM. Therefore, appropriate imaging-based assessment plays a crucial role in determining whether AS or surgery should be pursued. However, detailed recommendations concerning US evaluation are currently insufficient, necessitating the formulation of this guideline. The Korean Society of Thyroid Radiology has developed a consensus statement for low-risk PTMC, covering US assessment methods when considering AS as a management option and conducting follow-up imaging tests during AS. This guideline aims to provide optimal scientific evidence and expert opinion consensus regarding a standardized US-based assessment protocol for low-risk PTMC.

Thyroid cancer epidemiology in Ireland from 1994 to 2019 - Rising diagnoses without mortality benefit

BACKGROUND

The epidemiology and management of thyroid cancer has changed radically in the recent past, with rising international incidence of early-stage papillary thyroid cancer (PTC) in particular. In this paper, we review the epidemiology of thyroid cancer in Ireland.

METHODS

A retrospective cohort study of National Cancer Registry of Ireland data, 1994-2019.

RESULTS

Records from 4158 patients were analysed. 73 % (n = 3040) were female. The average age was 50.4 years. Patient sex did not change over time (p = 0.662), while age decreased significantly (p < 0.0001). The most common diagnoses were PTC (n = 2,905, 70 %) and follicular thyroid carcinoma (n = 549, 13 %). Incidence rose over threefold (1.8-6.2 cases/100000 person-years). The incidence of T1 PTC rose over twelvefold (0.169-2.1 cases/100000 person-years), while the incidence of stage III and IV disease did not change significantly. Five-year disease-specific survival (DSS) was 85 % and varied significantly by diagnosis - 97 % for PTC versus 5 % for anaplastic thyroid carcinoma. Survival did not change significantly over time. Male sex was a risk factor for more advanced disease (p < 0.0001) but did not independently predict overall survival except in PTC (HR 1.6, p = 0.03). The use of radioactive iodine declined markedly from 49 % to 12.5 %. RAI improved DSS for PTC patients aged over 55 years (p = 0.02) without a notable effect on survival for those under 55 years (p = 0.99).

CONCLUSION

The epidemiology and management of thyroid cancer in Ireland has changed dramatically in a manner reflective of international trends.

Impact of a simple informative leaflet on Brazilian doctors' attitudes towards active surveillance of thyroid microcarcinomas

Introduction

Active surveillance (AS) is increasingly recognized as an appropriate strategy for selected patients with papillary thyroid microcarcinomas (PTMC). However, some factors, including physician-related ones, hinder its widespread adoption.

Methods

To explore the prevailing barriers and the impact of information on attitudes towards AS implementation, we developed a questionnaire that was completed before and after reading a simple information leaflet by 317 doctors working in different work environments. This leaflet provides information about the overdiagnosis of PTMC, the concept of AS, results of early studies, and main advantages and disadvantages of AS.

Results

We observed a greater resistance to AS among male physicians who were more likely to maintain the initial recommendation for surgery or referral to a head and neck surgeon than female physicians (77 % vs. 46 %, p = 0.01), regardless of their medical specialty. Fear of disease progression and of the patient losing follow-up were the main concerns. Reading the educational material significantly increased the number of physicians who endorsed AS as an initial approach to PTMC without risk factors from 14 % to 34 % (p < 0,001). This change in attitude was even more significant when doctors were confronted with a case of PTMC in an elderly patient. Gender, medical specialty, age range and academic environment were the factors that were determinants on the influence of the informative leaflet on the decision-making. The leaflet also increased the number of doctors who considered themselves capable of dealing with this patient profile; however, 17 % declared that the place where they worked would not be able to meet the need for periodic assessments and necessary examinations. This was particularly true for the 20 % of the professionals working in rural areas.

Conclusion

A simple educational leaflet with basic information presented via social media increased the number of Brazilian physicians who endorsed AS for PTMC management and proved to be a facilitating tool for understanding and accepting it. Our results suggest that this method can be easily extended to larger population.

Thyroid cancer-specific mortality during 2005-2018 in Korea, aftermath of the overdiagnosis issue: a nationwide population-based cohort study

BACKGROUND

Thyroid cancer (TC) has underwent notable changes in its diagnosis and treatments following the concerns regarding overdiagnosis and overtreatment. However, there is little research on evaluating the effects of these alterations on TC-specific mortality.

MATERIALS AND METHODS

This population-based cohort study included 434 228 patients with TC using Korean National Health Insurance Service-National Health Information Database. The age-standardized and sex-standardized mortality rates of TC per 1000 person-years were calculated considering the number of patients diagnosed with TC in 2013 per our database to evaluate the TC-specific mortality trends according to the year of TC diagnosis.

RESULTS

The authors enrolled 434 228 patients with TC, including 352 678 women and 81 550 men, with a mean age of 48.6±12.5 years and a median follow-up duration of 7.4 (interquartile range: 4.5-10.1) years. TC incidence increased from 2005 to 2012, with a standardized rate of 91.9 per 100 000 people in 2012, decreased rapidly to 50.6 in 2015, and remained stable until 2018. However, TC-specific age-standardized and sex-standardized mortality rates decreased from 1.94 per 1000 person-years in 2005 to 0.76 per 1000 person-years in 2013 and then increased to 2.70 per 1000 person-years in 2018. The TC-specific age-standardized and sex-standardized mortality rates of patients who had undergone hemithyroidectomy or subtotal thyroidectomy remained steady during 2005-2018, but increased in patients who had undergone total thyroidectomy or not undergone thyroidectomy between 2013 and 2018.

CONCLUSIONS

The TC-specific mortality rates among patients with TC diagnosed since 2015 have increased, in contrast to the significant decline in TC incidence during the same period. This underscores the importance of appropriate diagnosis and treatment in patients with TC at high-risk of progression, simultaneously emphasizing efforts to reduce overdiagnosis and overtreatment in those with low-risk TC.

Ultrasound Imaging in Active Surveillance of Small, Low-Risk Papillary Thyroid Cancer

The recent surge in the incidence of small papillary thyroid cancers (PTCs) has been linked to the widespread use of ultrasonography, thereby prompting concerns regarding overdiagnosis. Active surveillance (AS) has emerged as a less invasive alternative management strategy for low-risk PTCs, especially for PTCs measuring ≤1 cm in maximal diameter. Recent studies report low disease progression rates of low-risk PTCs ≤1 cm under AS. Ongoing research is currently exploring the feasibility of AS for larger PTCs (<20 mm). AS protocols include meticulous ultrasound assessment, emphasis on standardized techniques, and a multidisciplinary approach; they involve monitoring the nodules for size, growth, potential extrathyroidal extension, proximity to the trachea and recurrent laryngeal nerve, and potential cervical nodal metastases. The criteria for progression, often defined as an increase in the maximum diameter of the PTC, warrant a review of precision and ongoing examinations. Challenges exist regarding the reliability of volume measurements for defining PTC disease progression. Although ultrasonography plays a pivotal role, challenges in assessing progression and minor extrathyroidal extension underscore the importance of a multidisciplinary approach in disease management. This comprehensive overview highlights the evolving landscape of AS for PTCs, emphasizing the need for standardized protocols, meticulous assessments, and ongoing research to inform decision-making.

Active surveillance versus immediate surgery in the management of low-risk papillary thyroid microcarcinoma: comparison of long-term costs in Brazil

Objective

To compare the long-term medical costs of active surveillance (AS), partial thyroidectomy (PT), and total thyroidectomy (TT) in patients with low-risk papillary thyroid microcarcinoma (PTMC) receiving care covered by the Brazilian Public Health System.

Materials and methods

After reviewing AS cohorts and our own data, we created a model of AS, PT, and TT flow care for low-risk PTMC over 10, 20, and 30 years. The medical costs included those associated with diagnosis, surgery, and follow-up. We considered that 13.3% of the patients on AS would require surgery after a mean of 21.3 months, 4% undergoing TT would develop permanent hypoparathyroidism, and 43% undergoing PT would develop hypothyroidism.

Results

The most economical alternative was AS. The costs of TT per patient were higher than those of AS by 182.8% over 10 years (866.89 versus 306.49 US dollars [USD], respectively), by 152.9% over 20 years (1,023.66 versus 404.73 USD, respectively), and by 134.7% over 30 years (1,180.42 versus 502.96 USD, respectively). The costs of PT per patient were higher than those of AS by 16.0% over 10 years (355.66 versus 306.49 USD, respectively), by 16.9% over 20 years (473.41 versus 404.73 USD, respectively), and by 17.5% over 30 years (591.17 versus 502.96 USD, respectively).

Conclusion

The AS approach was less costly than immediate surgery throughout 30 years of follow-up. Hence, the implementation of AS in Brazil should not be hindered by cost considerations.

Tumor Growth Kinetics Based on Initial Tumor Volume Doubling Time in Active Surveillance of Low-Risk Papillary Thyroid Carcinoma

Background: During active surveillance (AS) of low-risk papillary thyroid carcinomas (PTCs), the majority remain stable, while some exhibit either an increase or a decrease in tumor diameter or tumor volume (TV). We aimed to evaluate the clinical outcomes and relevant parameters influencing tumor growth kinetics of low-risk PTCs. Methods: This retrospective cohort study evaluated clinical parameters of 402 patients with low-risk PTC sized <2 cm, with a follow-up duration over 3 years. Changes in maximum tumor diameter, TV, and initial TV doubling time (i-TVDT) calculated within 3 years were assessed. A significant change in TV was defined as a change of 75% or more. Results: Of the 402 patients with low-risk PTC, 93.3% (375/402) were diagnosed with papillary thyroid microcarcinoma. During a median follow-up of 5 years, 3.4% (14/402) of patients developed new cervical lymph node (LN) metastasis, and 8.2% (33/402) experienced a maximal diameter increase of ≥3 mm. The i-TVDT of <5 years emerged as an independent risk factor for both maximal diameter growth and new LN metastasis (p < 0.001 and p = 0.04, respectively). Based on TV changes and i-TVDT during AS, we identified four statistically significant tumor kinetic patterns (p < 0.001): Stable (±75% change in TV), Rapid growth (TV increase >75% and i-TVDT <5 years), Slow growth (TV increase >75% and i-TVDT ≥5 years), and Shrinkage (TV decrease >75%). Most of the PTCs remained stable (67.7%), but 17.2% were rapidly growing, with a median onset of growth of 2.0 years. Slowly growing PTCs, comprising 10.9%, grew at a median of 4.3 years. A minority, 4.2%, exhibited shrinkage. In total, 115 (28.6%) patients underwent delayed surgery >12 months after initiating AS. The reasons for delayed surgery included patient preference (51/115, 44.3%), disease progression (31/115, 27.0%), and suspected disease progression, which was referred to as tumor growth not meeting the criteria of an increase of ≥3 mm in maximal tumor diameter (17/115, 14.8%). Conclusion: An i-TVDT of <5 years serves as an important prognostic indicator for disease progression, including tumor growth and new LN metastasis. The four tumor kinetic patterns based on TV changes and i-TVDT assist in guiding personalized decisions early in AS.

Implementing active surveillance for low-risk thyroid carcinoma into clinical practice: collaborative recommendations for Latin America

The incidence of thyroid cancer is increasing globally, but mortality rates have remained steady. Many patients with thyroid cancer have low-risk, nonmetastatic intrathyroidal tumors smaller than 2 cm. Active surveillance has shown benefits in these patients, but the adoption of this approach remains below standard in Latin America. The purpose of this article is to identify ways to improve the incorporation of active surveillance into clinical practice for patients with low-risk thyroid carcinoma in Latin America, taking into consideration cultural and geographic factors. Current recommendations include three steps involving patient participation. The first step, which consists of the initial clinical examination, has eight factors requiring special attention. Anxiety must be managed while considering individual, disease-related, cognitive, and environmental aspects. Terms like "overdiagnosis", "incidentaloma," and "overtreatment" must be explained to the patient. Implementing precise terminology contributes to adequate disease perception, substantially reducing stress and anxiety. Clarifying the nonprogressive nature of thyroid cancer helps dispel myths surrounding the disease. The second step includes advice about procedures and guidelines for patients who choose active surveillance. Flexible monitoring techniques should be implemented, with regular check-ins scheduled based on patient needs. Reasons for adjusting treatment must be clearly communicated to the patient, and changes in preference regarding active surveillance should be considered in advance. The third step includes assistance during follow-up. Patients must be educated about ultrasound results and receive surgical indications from specialized physicians. The effectiveness of active surveillance can be reinforced by explaining to the patients the dynamics of changes in nodule size using clear and concise visual aids.

Undercover active surveillance of small highly suspicious thyroid nodules without fine needle aspiration

PURPOSE

Active surveillance (AS) is an alternative treatment approach for small, low-risk papillary thyroid microcarcinoma (PTMC). This study aimed to assess the clinical outcomes of small, highly suspicious nodules lacking initial cytological confirmation.

METHODS

This study included 112 patients with highly suspicious nodules measuring ≤ 10 mm who underwent serial ultrasound at Asan Medical Center, Korea, between 2010 and 2023.

RESULTS

The median participant age was 51.9 years, and 74.1% were female. The median maximal tumor diameter and tumor volume (TV) were 4.5 (interquartile range [IQR] 3.7-5.2, range 2.2-9.3) mm and 25.2 (IQR 13.1-49.2) mm3, respectively. During a median follow-up period of 4.8 years, four (3.6%) patients showed a ≥ 3 mm increase in maximal diameter, and two (1.8%) developed new lymph node (LN) metastasis. Disease progression was associated with a TV doubling time (TVDT) of < 5 years and a ≥ 75% increase in TV (p = 0.017 and p < 0.005, respectively). Furthermore, 34.8% of patients underwent fine needle aspiration (FNA), primarily at their own request, yielding 46.2%, 5.1%, 41.0%, and 12.8 % malignant, benign, indeterminate, and non-diagnostic results, respectively. Of 18 patients with PTMC, 8 (44.4%) underwent surgery and 10 continued AS, with no LN metastasis during AS and no postoperative recurrence.

CONCLUSION

Small, highly suspicious nodules had a low disease progression rate during AS without FNA. Disease progression was associated with a TVDT of < 5 years and a ≥ 75% increase in TV. FNA can be performed more conservatively than it currently is in patients with highly suspicious nodules measuring ≤ 10 mm.

Malpractice Trends Involving Active Surveillance Across Cancers

OBJECTIVE

To characterize malpractice trends related to active surveillance (AS) as a treatment strategy across cancers.

BACKGROUND

Active surveillance is increasingly considered a viable management strategy for low-risk cancers. Since a subset of AS cases will progress, metastasize, or exhibit cancer-related mortality, a significant barrier to implementation is the perceived risk of litigation from missing the window for cure. Data on malpractice trends across cancers are lacking.

METHODS

Westlaw Edge and LexisNexis Advance databases were searched from 1990 to 2022 for malpractice cases involving active surveillance in conjunction with thyroid cancer, prostate cancer, kidney cancer, breast cancer, or lymphoma. Queries included unpublished cases, trial orders, jury verdicts, and administrative decisions. Data were compiled on legal allegations, procedures performed, and verdicts or settlements rendered.

RESULTS

Five prostate cancer cases were identified that pertained to active surveillance. Two cases involved alleged deliberate indifference from AS as a management strategy but were ruled as following the appropriate standard of care. In contrast, 3 cases involved alleged physician negligence for not explicitly recommending AS as a treatment option after complications from surgery occurred. All cases showed documented informed consent for AS, leading to defense verdicts in favor of the physicians. No cases of AS-related malpractice were identified for other cancer types.

CONCLUSIONS

To date, no evidence of successful malpractice litigation for active surveillance in cancer has been identified. Given the legal precedent detailed in the identified cases and increasing support across national guidelines, active surveillance represents a sound management option in appropriate low-risk cancers, with no increased risk of medicolegal exposure.

RAS-Mutated Cytologically Indeterminate Thyroid Nodules: Prevalence of Malignancy and Behavior Under Active Surveillance

Background: Genomic profiling is now available for risk stratification of cytologically indeterminate thyroid nodules (ITNs). Mutations in RAS genes (HRAS, NRAS, KRAS) are found in both benign and malignant thyroid nodules, although isolated RAS mutations are rarely associated with aggressive tumors. Because the long-term behavior of RAS-mutant ITNs is not well understood, most undergo immediate surgery. In this multicenter retrospective cohort study, we characterize tumor growth kinetics of RAS-mutant ITNs followed with active surveillance (AS) using serial ultrasound (US) scans and examine the histopathologic diagnoses of those surgically resected. Methods: US and histopathologic data were analyzed retrospectively from two cohorts: (1) RAS-mutant ITNs managed with AS at three institutions (2010-2023) and (2) RAS-mutant ITNs managed with immediate surgery at two institutions (2016-2020). AS cohort subjects had ≥3 months of follow-up and two or more US scans. Cumulative incidence of nodule growth was determined by the Kaplan-Meier method and growth by ≥72% change in tumor volume. Pathological diagnoses for the immediate surgery cohort were analyzed separately. Results: Sixty-two patients with 63 RAS-mutated ITNs under AS had a median diameter of 1.7 cm (interquartile range [IQR] 1.2-2.6) at time of diagnosis. During a median AS period of 23 months (IQR 9.5-53.5 months), growth was observed in 12 of 63 nodules (19.0%), with a cumulative incidence of 1.9% (1 year), 23.0% (3 years), and 28.0% (5 years). Most nodules (81.0%) demonstrated stability. Surgery was ultimately performed in 6 nodules, of which 1 (16.7%) was malignant. In the cohort of 209 RAS-mutant ITNs triaged to immediate surgery, 33% were malignant (23.9% American Thyroid Association [ATA] low-risk cancers, 7.2% ATA intermediate-risk, and 1.9% ATA high-risk. During a median follow-up of 6.9 (IQR 4.4-7.1) years, there were no disease-specific deaths in these patients. Conclusions: We describe the behavior of RAS-mutant ITNs under AS and find that most demonstrate stability over time. Of the resected RAS-mutant nodules, most were benign; of the cancers, most were ATA low-risk. Immediate surgical resection of all RAS-mutant ITNs appears to be a low-value practice. Further research is needed to help define cases most appropriate for AS or immediate surgery.

Tumor volume-doubling rate is negatively associated with patient age in papillary thyroid microcarcinomas under active surveillance

BACKGROUND

Active surveillance of low-risk papillary thyroid microcarcinomas has gained popularity worldwide as a management strategy. We previously reported that young age was associated with tumor enlargement by ≥3 mm. Here, we used the tumor volume-doubling rate to study the age-related tumor volume dynamics of papillary thyroid microcarcinomas under active surveillance.

METHODS

Between 2005 and 2019, 2,896 patients diagnosed with low-risk papillary thyroid microcarcinomas underwent active surveillance. We excluded patients who underwent ultrasound examination fewer than 4 times, had coexisting Graves' disease, or were treated with levothyroxine at the time of diagnosis, and we enrolled 2,129 patients for this study. We divided them into 3 subsets based on the age at diagnosis: young (<40 years), middle-aged (40-59 years), and elderly (≥60 years). The tumor volume-doubling rate was calculated based on ultrasound-derived tumor sizes and the respective examination date for each patient.

RESULTS

Overall, 140 patients (6.6%) had moderate or rapid growth (tumor volume-doubling rate ≥0.3/year), and the incidence significantly decreased with advanced age (P < .01): 11.3%, 7.1%, and 5.0% in the young, middle-aged, and elderly groups, respectively. Tumor regression (tumor volume-doubling rate <0/year) was detected in 1,200 patients (56.4%), and the incidence significantly increased with age (P < .01): 44.6%, 55.3%, and 60.0% in the young, middle-aged, and elderly groups, respectively. On multivariate analysis, both the ≥60 years and 40 to 59 years age groups were independent negative predictors of papillary thyroid microcarcinoma enlargement and positive predictors of tumor regression.

CONCLUSION

Tumor volume-doubling rate analysis demonstrated that the incidence of tumor enlargement decreased and that of tumor regression increased with advancing age in patients with papillary thyroid microcarcinomas.

Tumor growth manifested in two-fifths of low-risk papillary thyroid microcarcinoma patients during active surveillance: data from a tertiary center in China

Purpose

To assess tumor growth using tumor doubling rate (TDR) during active surveillance (AS) in China.

Methods

Between January 2016 and June 2020, a total of 219 patients with low-risk papillary thyroid microcarcinoma (PTMC) (aged 23-75 years) were consecutively enrolled in the AS program.

Results

Four sections of TDR, >0.5, 0.1~0.5, -0.1~0.1 and <-0.1, corresponded with four categories of tumor volume kinetics: rapid growth, slow growth, stable, and decreased size. We found that 10.5% of PTMCs exhibited rapid growth, 33.33% exhibited slow growth, 26.48% were stable, and 29.68% decreased in size. Tumor growth was associated with two factors: age and volume of PTMC at diagnosis. 85.72% of elderly patients (≥ 61 years old) had tumors that remained stable or even shrank and rapidly growing tumors were not found in them. When the volume was small (≤14.13 mm3), the proportion of rapid growth was high (41.67%), whereas when the volume was large (> 179.5 mm3), the proportion of non-growth was 68.75%.

Conclusion

TDR may be a better metric for evaluating tumor growth in observational PTMCs. A certain proportion of PTMCs grow during the period of AS and tumor growth was associated with age and volume of PTMC at initial diagnosis. Therefore, how to block tumor growth during the AS period, especially for young patients and patients with early-stage PTMC (size ≤ 5 mm), will be a new challenge.

Thirty years of active surveillance for low-risk thyroid cancer, lessons learned and future directions

Active Surveillance is a non-invasive strategy designed to identify a minority of patients with low-risk papillary thyroid carcinoma who might experience clinical progression and benefit from additional definitive treatments. Global experience suggests that these tumors typically show minimal changes in size during active surveillance, often demonstrating very slow growth or even size reduction. Moreover, the rate of lymph node metastases is low and can be effectively managed through rescue surgery, without impacting cancer-related mortality. However, despite 30 years of experience demonstrating the safety and feasibility of active surveillance for appropriately selected patients, this approach seems to have limited adoption in specific contexts. This limitation can be attributed to various barriers, including disparities in access to accurate information about the indolent nature of this disease and the prevalence of a maximalist mindset among certain patients and medical settings. This review aims to revisit the experience from the last three decades, provide current insights into the clinical outcomes of active surveillance trials, and propose a systematic approach for its implementation. Furthermore, it intends to emphasize the importance of precise patient selection and provides new perspectives in the field.

Active surveillance for micropapillary thyroid carcinoma: a clinical review

With the rapid rise in the incidence of micropapillary carcinoma, there is increasing concern about its overdiagnosis and overtreatment. There is considerable interest in managing patients with micropapillary carcinoma with active surveillance or deferred intervention. Various institutions around the world are practicing active surveillance. The major question remains as to who the ideal candidates are and how best to monitor these patients. This clinical review will discuss the ideal, appropriate, and inappropriate patients for active surveillance. It will also discuss the follow-up strategy for these patients and some of the adverse clinical features that will be used to decide against active surveillance. There are uncertainties as to who should be offered active surveillance. Various studies have shown approximately 10% of the patients switching to surgery primarily related to fear factor rather than increase in the tumor size or lymph node metastasis. The results of immediate surgery do raise issues related to complications of thyroid surgery and quality of life. The most ideal candidate would be patients with a tumor below 1 cm, intrathyroidal. For the patient who is a minimalist, the follow up strategy includes, ultrasound every 6 months for the first 1 or 2 years, and then every year after that. If there is a substantial change in the tumor volume or nodal metastasis, surgery should be considered, which happens in less than 10 percent of patients according to many studies. Based on existing literature and clinical experience, it appears that active surveillance is an appropriate strategy for monitoring micropapillary carcinoma.

Recent advances in head and neck surgical oncology

In recent years, the field of head and neck oncology has witnessed a remarkable transformation with unprecedented advances that have revolutionized the management of complex tumors in this region. As an intricate subspecialty within oncology, head and neck surgical procedures demand detailed knowledge of the complex anatomy meticulous precision in surgical technique, and expertise to preserve vital functions while ensuring optimal oncological outcomes. With the relentless pursuit of improved patient outcomes, the integration of innovative technologies has significantly enhanced the surgical armamentarium. Robotics, endoscopic platforms, and image-guided navigation have revolutionized the surgical approach, enabling precise tumor resection and sparing healthy tissues. Furthermore, the application of advanced imaging modalities and molecular biomarker profiling has opened new avenues for personalized treatment strategies. From targeted therapies and immunotherapies to adaptive radiation techniques, clinicians are now equipped with an array of tailored options, ushering in a new era of personalized care for patients with head and neck malignancies. This article delves into the unfolding narratives of clinical triumphs, exploring the transformative potential of emerging therapies and the collaborative efforts propelling head and neck surgical oncology toward a future of hope and healing.

Criteria to Evaluate Tumor Enlargement During the Active Surveillance of High-Risk Thyroid Nodules: Which is Better, Diameter or Volume?

INTRODUCTION

Tumor enlargement is the most common parameter identifying disease progression during active surveillance, but the value and significance of the changes in tumor diameter and volume in the evaluation of tumor growth have not been compared.

METHODS

This cohort study included 468 patients with high-risk thyroid nodule, in whom nodule size change was monitored using ultrasound, to compare the changes in tumor diameter and volume in assessing tumor growth.

RESULTS

A total of 569 high-risk thyroid nodules were found in the 468 patients. A total of 14 nodules (2.5%) showed a diameter increase ≥ 3 mm. The number of nodules with a peak volume change exceeding 50% and 100% was 185 (32.5%) and 86 (15.1%), respectively. Among the 555 stable nodules, the number of nodules with volume fluctuations exceeding 50% and 100% was 171 (30.8%) and 72 (13.0%), respectively. Among 212 stable nodules at the baseline and in the first three follow-up, the percentage of peak volume fluctuations exceeding 50% (48.5% vs. 28.5%, p = 0.004) and 100% (26.5% vs. 8.3%, p < 0.001) in the nodules with the sum of three diameters (SOTDs) ≤ 1 cm was significantly higher than that of nodules with SOTDs > 1 cm. A statistically significant difference was also found in the range distribution of SOTDs ≤ 1 cm and SOTDs > 1 cm (p = 0.007).

CONCLUSIONS

Volume is not an appropriate method for determining tumor growth. Tumor diameter measurement alone serves as a better surrogate for disease progression in sonographically high-risk thyroid nodules than volume.

Is Multifocality a Predictor of Poor Outcome in Childhood and Adolescent Papillary Thyroid Carcinoma?

CONTEXT

Total thyroidectomy in pediatric papillary thyroid carcinoma (PTC) is recommended in national guidelines because of the high incidence of multifocal disease (MFD).

OBJECTIVE

To determine the incidence of MFD in childhood and adolescent vs adult PTC and whether MFD is a predictor for poorer outcomes in childhood and adolescent PTC.

METHODS

We conducted an institutional review board-approved review of patients with PTC undergoing surgery (1986-2021) at Memorial Sloan Kettering Cancer Center. Clinical and pathological characteristics in patients with unifocal disease (UFD) and MFD were compared using Pearson's χ2 test. Survival outcomes were analyzed using the Kaplan-Meier method and log-rank test. Multivariate analysis assessed the impact of MFD on outcome.

RESULTS

MFD was less common in childhood and adolescent patients with PTC (45%; 127/283) than in adults (54%; 3023/5564; P = .002). Childhood and adolescent patients with UFD and MFD had similar tumor stage and PTC subtype at presentation, with no significant difference in histopathologic features. Median follow-up was 68 months. There was no significant difference in 5-year recurrence-free probability and overall survival was 100% in both groups. There was no significant difference in 5-year contralateral lobe PTC-free probability between patients with UFD and MFD treated with lobectomy. Multivariate analysis showed MFD was not a predictor for recurrence.

CONCLUSION

MFD was less common in childhood and adolescent patients with PTC than adults and was not a predictor of poor outcome on multivariate analysis, with excellent long-term outcomes in all patients with PTC. MFD does not appear to warrant completion thyroidectomy in childhood and adolescent patients selected for lobectomy.

Development of a novel clinical support tool for active surveillance of low risk papillary thyroid cancer

Background

Active surveillance (AS) is an alternative to surgery in select patients with very low risk papillary thyroid cancer (PTC). Many clinicians feel ill-equipped in selecting appropriate patients. We aimed to 1) Develop an evidence-based web delivered decision support tool to assist clinicians in identifying patients appropriate for AS; and 2) Evaluate the prevalence of patients suitable for AS in a tertiary high volume thyroid cancer centre.

Method

A REDCap web based clinical support tool was developed utilising evidence-based characteristics for AS suitability available to clinicals during initial assessment. A retrospective database was interrogated for patients who underwent hemithyroidectomy between 2012 - 2021 with final histopathology demonstrating PTC. Patients with PTCs>2cm, missing data, benign disease on surgical histopathology or incidental PTC were excluded.

Results

Between 2012 - 2021, 763 patients underwent hemithyroidectomy with final histopathology confirming PTC. Of these, 316 patients were excluded (missing data, incidental PTC, concomitant hyperparathyroidism were most common reasons for exclusion) and 114/447 remaining patients had a pre-operative fine needle aspirate (FNA) of Bethesda V or VI (high likelihood of malignancy). Using the tool, 59/114 (52%) met criteria for AS. The majority of patients were female (85% vs 15% male); median age 36 years (range 19 - 78). Following initial surgery, 10/59 patients had a completion thyroidectomy, with 4/10 demonstrating malignancy in contralateral lobe and eight of those patients undergoing I131 ablation. During a median follow up of over 3 years, 49/59 (83%) did not require further surgery or intervention with no patients developing recurrence. A subgroup analysis with second radiology assessment excluded 4/59 patients as meeting criteria for AS based on presence of ETE on preoperative ultrasound. None of these 4 patients had completion thyroidectomy.

Conclusion

Our clinical support tool identifies patients with PTC potentially suitable for AS which could be utilised during initial patient assessment. In a retrospective cohort of patients who had hemithyroidectomy for PTC with a pre-operative FNA diagnosis of Bethesda V or VI, 55/114 (48%) patients may have been suitable for AS. Prospective validation studies are required for implementation of the tool in clinical practice.

Conservative management of low-risk papillary thyroid carcinoma: a review of the active surveillance experience

The detection of low-risk thyroid carcinoma has increased in recent decades, although disease-specific mortality remained without changes. The high prevalence of occult carcinomas in autopsy studies, and hence the underlying indolent course of this entity, prompted the emergence of active surveillance as an alternative approach to these tumors. This strategy aims to recognize the minority group of patients who will develop clinical progression and probably benefit from deferred surgery. Experience around the world has shown that during active surveillance these tumors are mostly unchanged in size, with very-slow growth and even a decrease in diameter. Moreover, the rates of lymph node metastases were low and easily handled by rescue surgery, and distant metastases have not been reported. Given the high prevalence of small thyroid carcinomas and the excellent outcomes for observation, active surveillance provides a safe and feasible alternative in properly selected patients with low-risk thyroid cancer.