Cost-effectiveness of active surveillance versus hemithyroidectomy for micropapillary thyroid cancer

Cost-Effectiveness of the ACR TIRADS Compared to the ATA 2015 Risk Stratification Systems in the Evaluation of Incidental Thyroid Nodules

RATIONALE AND OBJECTIVES

Thyroid nodules are a common incidental imaging finding and prone to overdiagnosis. Several risk stratification systems have been developed to reduce unnecessary work-up, with two of the most utilized including the American Thyroid Association 2015 (ATA2015) and the newer American College of Radiology Thyroid Imaging, Reporting and Data System (TIRADS) guidelines. The purpose of this study is to evaluate the cost-effectiveness of the ATA2015 versus the TIRADS guidelines in the management of incidental thyroid nodules.

METHODS

A cost-utility analysis was conducted using decision tree modeling, evaluating adult patients with incidental thyroid nodules < 4 cm. Model inputs were populated using published literature, observational data, and expert opinion. Single-payer perspective, Canadian dollar currency, five-year time horizon, willingness to pay (WTP) threshold of $50,000, and discount rate of 1.5% per annum were utilized. Scenario, deterministic and probabilistic sensitivity analyses were performed. The primary outcome was the incremental cost-effectiveness ratio (ICER) expressed as incremental cost per quality-adjusted life year (QALY) gained.

RESULTS

For the base case scenario, TIRADS dominated the ATA2015 strategy by a slim margin, producing 0.005 more QALYs at $25 less cost. Results were sensitive to the malignancy rate of biopsy and the utilities of a patient with a benign nodule/subclinical malignancy or under surveillance. Probabilistic sensitivity analysis showed that TIRADS was the more cost-effective option 79.7% of the time.

CONCLUSION

The TIRADS guidelines may be the more cost-effective strategy by a small margin compared to ATA2015 in most scenarios when used to risk stratify incidental thyroid nodules.

Active Surveillance for Low-Risk Papillary Thyroid Carcinoma as an Acceptable Management Option with Additional Benefits: A Comprehensive Systematic Review

BACKGRUOUND

Active surveillance (AS) has been introduced as a management strategy for low-risk papillary thyroid carcinoma (PTC) due to its typically indolent nature. Despite this, the widespread adoption of AS has encountered several challenges. The aim of this systematic review was to evaluate the safety of AS related to disease progression and its benefits compared with immediate surgery (IS).

METHODS

Studies related to AS in patients with low-risk PTC were searched through the Ovid MEDLINE, Embase, Cochrane Library, and KoreaMed databases. Studies on disease progression, surgical complication, quality of life (QoL), and cost-effectiveness were separately analyzed and narratively synthesized.

RESULTS

In the evaluation of disease progression, the proportions of cases with tumor growth ≥3 mm and a volume increase >50% were 2.2%-10.8% and 16.0%-25.5%, respectively. Newly detected lymph node metastasis was identified in 0.0%-1.4% of patients. No significant difference was found between IS and delayed surgery in surgical complications, including vocal cord paralysis and postoperative hypoparathyroidism. AS was associated with better QoL than IS. Studies on the cost-effectiveness of AS reported inconsistent data, but AS was more cost-effective when quality-adjusted life years were considered.

CONCLUSION

AS is an acceptable management option for patients with low-risk PTC based on the low rate of disease progression and the absence of an increased mortality risk. AS has additional benefits, including improved QoL and greater QoL-based cost-effectiveness.

Active Surveillance for Low-Risk Thyroid Cancers: A Review of Current Practice Guidelines

The indolent nature and favorable outcomes associated with papillary thyroid microcarcinoma have prompted numerous prospective studies on active surveillance (AS) and its adoption as an alternative to immediate surgery in managing low-risk thyroid cancer. This article reviews the current status of AS, as outlined in various international practice guidelines. AS is typically recommended for tumors that measure 1 cm or less in diameter and do not exhibit aggressive subtypes on cytology, extrathyroidal extension, lymph node metastasis, or distant metastasis. To determine the most appropriate candidates for AS, factors such as tumor size, location, multiplicity, and ultrasound findings are considered, along with patient characteristics like medical condition, age, and family history. Moreover, shared decision-making, which includes patient-reported outcomes such as quality of life and cost-effectiveness, is essential. During AS, patients undergo regular ultrasound examinations to monitor for signs of disease progression, including tumor growth, extrathyroidal extension, or lymph node metastasis. In conclusion, while AS is a feasible and reliable approach for managing lowrisk thyroid cancer, it requires careful patient selection, effective communication for shared decision-making, standardized follow-up protocols, and a clear definition of disease progression.

Recommend with caution: A meta-analysis investigating papillary thyroid carcinoma tumor progression under active surveillance

BACKGROUND

Papillary thyroid carcinoma (PTC) is an indolent disease with favorable outcomes. The non-surgical treatment approach known as active surveillance (AS) has been introduced as an alternative treatment instead of the traditional thyroidectomy. However, 10-15 % of PTC tend to progress. We sought to determine factors predicting the progression of PTC under AS.

METHODS

A systematic search was performed in January 2022 using PubMed, Embase, Google Scholar, Web of Science, and ScienceDirect. PRISMA guidelines were used by multiple reviewers to extract study characteristics (author name, publication date, journal name, country, institution, and study design), as well as main outcomes and measures. A combination of utilization of thyroid replacement therapy, baseline tumor size and volume, follow-up tumor size and volume, and the presence of lymph node metastasis and its distribution, as well as surveillance duration, were the main measures of this study.

RESULTS

Nine studies with 4166 patients were included, of which 354 showed tumor progression during AS (15 %; 95%CI = 7 % - 23 %). The average follow-up period was 41.58 months. The mean tumor maximum diameter was 8.54 mm (95%CI = 7.04-10.03). Tumor progression was most commonly secondary to an increase in volume by ≥50 % (75 %; 95%CI = 68 % - 80 %), then increase in diameter by ≥3 mm (41 %; 95%CI = 13 % - 76 %), and finally the development of lymph node metastasis (13 %; 95%CI = 9 % - 19 %). Approximately only 2 % of all patients thus developed new lymph node metastasis. Patient age, sex, and tumor size were not associated with higher risks of tumor progression. 12 % of AS patients eventually underwent surgery, though only 40 % (95%CI = 27 % - 53 %) of these patients displayed tumor progression.

CONCLUSIONS

Our meta-analysis determined a tumor progression rate of 15 % in patients who underwent AS management, 13 % of which (2 % of all patients) developed lymph node metastasis. We found no protective or risk factors for tumor progression, and that almost half of all patients who underwent delayed surgery did so for reasons other than tumor progression. While not biopsying small (<1 cm) or very low suspicious nodules is already recommended, AS may be an appropriate treatment option in patients appropriately counseled, considering the low risk of advanced tumor progression but also the considerable patient population who fail to adhere to treatment. Alternatively, in aim of preventing overtreatment in patients who would rather take proactive measures against their low-risk carcinoma, minimally-invasive ablation techniques may be an attractive option.

Cost-Effectiveness of Active Surveillance Compared to Early Surgery of Small Papillary Thyroid Cancer: A Retrospective Study on a Korean Population

BACKGROUND

Recently, active surveillance (AS) has been introduced as an alternative to early surgery (ES) for the management of papillary thyroid microcarcinoma (PTMC), because of its indolent features and low mortality. However, its cost effects have not been determined and the findings of current studies differ, according to each country's medical system.

METHODS

A Markov model was constructed to compare the cost-effectiveness of AS and ES, based on a reference case of a 40-year-old patient diagnosed with PTMC. Costs and transition probabilities were derived from previous clinical studies in Korean populations, and the incremental cost-effectiveness ratio (ICER) and net monetary benefit (NMB) were calculated. The willingness-to-pay (WTP) threshold was set at USD 100,000 per quality-adjusted life year (QALY) gained. Sensitivity analyses were conducted to address the uncertainties in the model's variables.

RESULTS

From the base scenario, the cumulative costs and effectiveness were both higher in ES than AS. The ICER for ES, compared with AS, was USD 6,619.86/QALY, lower than the set WTP. The NMB difference between AS and ES increased across the stages (USD 5,980 at the first stage and USD 159,667 at the last stage). The ICER increased along with decreasing age and increasing cost of surgery. The higher the ES utility score and the lower that of AS, the more cost-effective ES, with WTP set at USD 30,000.

CONCLUSION

In the current Korean medical system, ES is more cost-effective than AS. ES is more cost-effective as it is diagnosed at young age and followed-up for a long time.

Cost-effectiveness of active surveillance versus early surgery for thyroid micropapillary carcinoma based on diagnostic and treatment norms in China

Objectives

In this study, we compared the cost-effectiveness comparison of the active surveillance (AS) and early surgery (ES) approaches for papillary thyroid microcarcinoma (PTMC) from the perspective of the Chinese healthcare system.

Methods

We performed a cost-effectiveness analysis using a Markov model of PTMC we developed to evaluate the incremental cost-effectiveness ratio of AS and ES. Our reference case was of a 40-year-old woman diagnosed with unifocal (<10 mm) PTMC. Relevant data were extracted after an extensive literature review, and the cost incurred in each state was determined using China Medicare data on payments for ES and AS. The willingness-to-pay threshold was set at ¥242,928/quality-adjusted life-year (QALY) gained. Sensitivity analyses were performed to account for any uncertainty in the model's variables. Additional subgroup analyses were performed to determine whether AS was cost-effective when different initial monitoring ages were used.

Results

ES exhibited an effectiveness of 5.2 QALYs, whereas AS showed an effectiveness of 25.8 QALYs. Furthermore, the incremental cost-effectiveness ratio for ES versus AS was ¥1,009/QALY. The findings of all sensitivity analyses were robust. Compared with ES, AS was found to be the cost-effective strategy at initial monitoring ages of 20 and 60 years, with an incremental cost-effectiveness ratio of ¥3,431/QALY and -¥1,316/QALY at 20 and 60 years, respectively. AS was a more cost-effective strategy in patients with PTMC aged more than 60.

Conclusions

With respect to the norms of the Chinese healthcare system, AS was more cost-effective for PTMC over lifetime surveillance than ES. Furthermore, it was cost-effective even when the initial monitoring ages were different. In addition, if AS is incorporated into the management plan for PTMC in China at the earliest possible stage, a predicted savings of ¥10 × 108/year could be enabled for every 50,000 cases of PTMC, which indicates a good economic return for future management programs. The identification of such nuances can help physicians and patients determine the best and most individualized long-term management strategy for low-risk PTMC.

High-Suspicion Subcentimeter Thyroid Nodules: Cost Effectiveness of Active Surveillance versus Fine Needle Aspiration

PURPOSE

To compare the cost-benefit of active surveillance (AS) against immediate fine needle aspiration (FNA) of sonographically suspicious subcentimeter thyroid nodules.

MATERIALS AND METHODS

A Markov model was constructed to compare the cost-benefit of 3 strategies from the point of discovery until death: (a) Surveillance of all nodules, (b) Surveillance of nodules with positive cytology, and (c) Surgery of nodules with positive cytology. The reference case was a 40-year-old woman with a sonographically suspicious subcentimeter thyroid nodule. Transition probabilities, costs, and health state utilities were derived from the literature. Sensitivity analyses were performed to evaluate model uncertainty. Willingness-to-pay threshold was set at $100,000/quality-adjusted life year.

RESULTS

Surveillance of nodules with positive cytology dominated in the reference scenario and was cost-beneficial over Surveillance of all nodules, independent of the utility of AS. Surveillance of all nodules was cost-beneficial only at a life expectancy of <2.6 years or surveillance duration of <4 years.

CONCLUSIONS

While current guidelines recommend AS of sonographically suspicious subcentimeter nodules, the results of this study suggest that immediate FNA (Surveillance of nodules with positive cytology) is more cost-beneficial than AS (Surveillance of all nodules). Patients with positive cytology on FNA may subsequently opt for AS (Surveillance of nodules with positive cytology) or surgery (Surgery of nodules with positive cytology) according to their level of comfort (ie, utility) with AS.

Active surveillance of low-risk papillary thyroid microcarcinoma

Recently, the incidence of thyroid carcinoma has been increasing rapidly worldwide. This is interpreted as an increase in the incidental detection of small papillary thyroid carcinomas by the widespread use of high-resolution imaging techniques such as ultrasonography. However, the mortality rates of thyroid carcinoma have not changed, suggesting that small papillary thyroid carcinomas may be overdiagnosed and overtreated. Active surveillance management has been introduced from Japan since the 1990s, as one of the measures to prevent overtreatment of low-risk papillary thyroid microcarcinoma. Based on the favorable outcomes, active surveillance has been gradually adopted worldwide as an alternative to immediate surgery. The management should be carried out with strict eligibility criteria and close monitoring for cancer progression, under a multidisciplinary team. In addition, an adequate shared decision-making is mandatory for individual patients. Papillary thyroid microcarcinomas with clinically apparent lymph node metastasis, distant metastasis, or invasion to adjacent organs should have surgery.

Endocrine surgeons are performing more thyroid lobectomies for low-risk differentiated thyroid cancer since the 2015 ATA guidelines

BACKGROUND

The 2015 American Thyroid Association guidelines recommended either total thyroidectomy or lobectomy for surgical treatment of low-risk differentiated thyroid cancer and de-escalated recommendations for central neck dissections. The study aim was to investigate how practice patterns among endocrine surgeons have changed over time.

METHODS

All adult patients with low-risk differentiated thyroid cancers (T1-T2, N0/Nx, M0/Mx) in the Collaborative Endocrine Surgery Quality Improvement Program (2014-2021) were identified. The outcomes between patients undergoing lobectomy versus total thyroidectomy were compared using multivariable logistic regression. The annual percent change in the proportion of lobectomies and central neck dissections performed was estimated using joinpoint regression.

RESULTS

In total, 5,567 patients with low-risk differentiated thyroid cancers were identified. Of these, 2,261 (40.6%) were very low-risk tumors ≤1 cm, and 2,983 (53.6%) were low-risk tumors >1 and <4 cm. Most patients (67.9%) underwent total thyroidectomy. Compared to total thyroidectomy, lobectomy was associated with outpatient surgery (adjusted odds ratio 5.19, P < .001), a decreased risk of postoperative emergency department visits (adjusted odds ratio 0.63, P = .03), and decreased risk of hypoparathyroidism events (adjusted odds ratio 0.03, P < .001). Compared to before (2014-2015), patients undergoing surgery after publication of the revised guidelines (2016-2021) had higher odds of lobectomy and lower odds of central neck dissection for tumors ≤1 cm (lobectomy adjusted odds ratio 2.70, P < .001; central neck dissections adjusted odds ratio 0.64, P = .03) and tumors between 1 and 4 cm (lobectomy adjusted odds ratio 2.27, P < .001; central neck dissection adjusted odds ratio 0.62, P < .001).

CONCLUSION

After publication of the 2015 American Thyroid Association guidelines, there has been an increase in thyroid lobectomies as a proportion of all thyroid operations performed by endocrine surgeons for low-risk differentiated thyroid cancer. This has implications for reduced health care use and costs, with potential population-level benefits.

Less-Intensive Management Options for Low-Risk Thyroid Cancer

The incidence of thyroid cancer is increasing, whereas mortality remains relatively stable. An increasing body of research supports the use of less-intensive treatment for low-risk thyroid cancer, as the overall prognosis is excellent. Although total thyroidectomy was the gold standard for many years, the options of lobectomy alone, active surveillance, and other ablative modalities are increasingly being used. The clinicohistologic features of any thyroid cancer are important to help determine the optimal management for a given tumor. However, the patient's own desires and goals in their cancer treatment must be evaluated.

Active Surveillance Versus Immediate Surgery for Low-Risk Papillary Thyroid Microcarcinoma Patients in South Korea: A Cost-Minimization Analysis from the MAeSTro Study

Background: Active surveillance (AS) has been established as an alternative to immediate surgery for low-risk papillary thyroid microcarcinoma (PTMC). Nonetheless, it remains difficult to decide between AS and immediate surgery, since limited objective evidence exists regarding risks and benefits. The aim of study is to compare the cumulative costs of AS and immediate surgery. Methods: To estimate cumulative costs, a hypothetical model is simulated based on the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Micro-Carcinoma (MAeSTro) study, a multicenter prospective cohort study of AS for PTMC. Direct and indirect costs are estimated from diagnosis to the treatment decision and follow-up for 10 years and a longer period. In the case of the scenarios, AS, AS to surgery due to changing their mind, and lobectomy (analyzed regardless of levothyroxine [LT4] treatment, as well as subdivided into lobectomy/LT4[-] and lobectomy/LT4[+]) are considered. A sensitivity analysis is performed using different discount rates to address uncertainties in future time costs. To compare the cumulative costs, we referred to previous research conducted in Hong Kong, the United States, and Japan. Results: The initial cost of AS is estimated to be 5.6 times lower than that of lobectomy (regardless of LT4 use), while the 10-year cumulative costs of AS ($2545) and lobectomy regardless of LT4 ($3045) are similar under a discount rate of 3%. However, in the long-term follow-up period, immediate surgery is going to be estimated more economical than AS. The costs of the two management approaches are similar in Hong Kong, but substantially different in the United States and Japan, implying that it could be affected by each country's national health insurance coverage and the thyroid ultrasound interval during follow-up. Conclusion: Considering both direct and indirect costs, the cumulative costs of AS and immediate surgery in low-risk PTMC patients are similar during 10 years, and surgery could be more economical for patients with a life expectancy in long-term follow-up. However, careful interpretation is needed for long-term follow-up and the country's health care system and environment. Nevertheless, considering the representative protocols and objective costs in South Korea, it is expected to be a key to suggest the appropriate treatment for PTMC patients.

Cost-Effectiveness Analysis of Active Surveillance Compared to Early Surgery in Small Papillary Thyroid Cancer: A Systemic Review

Papillary thyroid microcarcinoma (PTMC) has indolent features and low mortality. Recently, active surveillance (AS) instead of early surgery (ES) has been introduced as one treatment option but economical preference has not been established. The study objective was to systemically review the literature relating to cost-effectiveness of AS compared to ES for PTMC. Keywords were selected through PICO (Population, Intervention, Comparison, and Outcomes) tools. The search was conducted using PubMed, Cochrane, EMBASE, and Elsevier databases. Papers that had irrelevant titles were written in foreign languages, or had no original results were excluded. Out of the 62 papers extracted, five relevant to the subject matter of this study were identified. Three papers made their own decision models and proceeded with cost-effectiveness analysis (CEA), but the remaining two simply compared costs rather than cost-effectiveness. In terms of cost-effectiveness, three papers preferred AS, one preferred ES, and one preferred neither. The major differences in the CEA might arise from variations in each country’s medical insurance system, the utility score systems, and decision models used. In subgroup analysis, two papers preferred AS to ES for patients at a younger age at diagnosis in terms of cost-effectiveness as well as tumor biological characteristics. Although AS has been generally more cost-effective than ES in previous publications, younger age at diagnosis could be one factor contributing to preference for ES. The CEA of prospective cohorts based on the decision model and utility score for thyroid cancer should be undertaken to confirm the cost-effectiveness of AS.

Thyroid lobectomy as a cost-effective approach in low-risk papillary thyroid cancer versus active surveillance

BACKGROUND

An ongoing debate exists over the optimal management of low-risk papillary thyroid cancer. The American Thyroid Association supports the concept of active surveillance to manage low-risk papillary thyroid cancer; however, the cost-effectiveness of active surveillance has not yet been established. We sought to perform a cost-effectiveness analysis comparing active surveillance versus surgical intervention for patients in the United States.

METHODS

A Markov decision tree model was developed to compare active surveillance and thyroid lobectomy. Our reference case is a 40-year-old female who was diagnosed with unifocal (<15 mm), low-risk papillary thyroid cancer. Probabilistic outcomes, costs, and health utilities were determined using an extensive literature review. The willingness-to-pay threshold was set at $50,000/quality-adjusted life year gained. Sensitivity analyses were performed to account for uncertainty in the model's variables.

RESULTS

Lobectomy provided a final effectiveness of 21.7/quality-adjusted life years, compared with 17.3/quality-adjusted life years for active surveillance. Furthermore, incremental cost effectiveness ratio for lobectomy versus active surveillance was $19,560/quality-adjusted life year (<willing-to-pay threshold of $50,000/quality-adjusted life year), and thus surgical intervention proved to be cost-effective in patients between 40 and 69 years old. Further analysis revealed that, at the age of 69 years, active surveillance is more cost-effective than lobectomy, with a final effectiveness of 17.3/quality-adjusted life years. Compared to active surveillance, the incremental cost effectiveness ratio for lobectomy at the age of 69 was $27,235/quality-adjusted life year, which decreases quality-adjusted life years by 1.5.

CONCLUSION

Lobectomy is a cost-effective strategy in middle-aged patients with low-risk papillary thyroid cancer. In contrast, active surveillance is cost-effective beginning at the age of 69. Identification of such nuances can help physicians and patients determine the best, most individualized long-term management strategy for low-risk papillary thyroid cancer.

The Concept of Economic Evaluation and Its Application in Thyroid Cancer Research

Economic evaluation is a type of comparative analysis between interventions in terms of both their resource use and health outcomes. Due to the good prognosis of thyroid cancer (TC), the socioeconomic burden of TC patients post-diagnosis is increasing. Therefore, economic evaluation studies focusing on TC are recommended. This study aimed to describe the concept and methods of economic evaluation and reviewed previous TC studies. Several previous studies compared the costs of interventions or evaluated recurrence, complications, or quality of life as measures of their effectiveness. Regarding costs, most studies focused on direct costs and applied hypothetical models. Cost-minimization analysis should be distinguished from simple cost analysis. Furthermore, due to the universality of the term "cost-effectiveness analysis" (CEA), several studies have not distinguished CEA from cost-utility analysis; this point needs to be considered in future research. Cost-benefit analyses have not been conducted in previous TC research. Since TC has a high survival rate and good prognosis, the need for economic evaluations has recently been pointed out. Therefore, correct concepts and methods are needed to obtain clear economic evaluation results. On this basis, it will be possible to provide appropriate guidelines for TC treatment and management in the future.

Position paper from the Japan Thyroid Association task force on the management of low-risk papillary thyroid microcarcinoma (T1aN0M0) in adults

The incidence of thyroid carcinoma has been increasing worldwide. This is interpreted as an increase in the incidental detection of papillary thyroid microcarcinomas (PTMCs). However, mortality has not changed, suggesting overdiagnosis and overtreatment. Prospective clinical trials of active surveillance for low-risk PTMC (T1aN0M0) have been conducted in two Japanese institutions since the 1990s. Based on the favorable outcomes of these trials, active surveillance has been gradually adopted worldwide. A task force on the management of PTMC in adults organized by the Japan Thyroid Association therefore conducted a systematic review and has produced the present position paper based on the scientific evidence concerning active surveillance. This paper indicates evidence for the increased incidence of PTMC, favorable surgical outcomes for low-risk PTMC, recommended criteria for diagnosis using fine needle aspiration cytology, and evaluation of lymph node metastasis (LNM), extrathyroidal extension (ETE) and distant metastasis. Active surveillance has also been reported with a low incidence of disease progression and no subsequent recurrence or adverse events on survival if conversion surgery was performed at a slightly advanced stage. Active surveillance is a safe and valid strategy for PTMC, because it might preserve physical quality of life and reduce 10-year medical costs. However, some points should be noted when performing active surveillance. Immediate surgery is needed for PTMC showing high-risk features, such as clinical LNM, ETE or distant metastasis. Active surveillance should be performed under an appropriate medical team and should be continued for life.

Thyroid cancer, recent advances in diagnosis and therapy

Over the past several decades, the approach to the diagnosis and management of patients with follicular cell-derived thyroid cancer has evolved based on improved classification of patients better matching clinical outcomes, as well as advances in imaging, laboratory, molecular technologies and knowledge. While thyroid surgery, radioactive iodine therapy and TSH suppression remain the mainstays of treatment, this expansion of knowledge has enabled de-escalation of therapy for individuals diagnosed with low-risk well-differentiated thyroid cancer; better definition of treatment choices for patients with more aggressive disease; and improved ability to optimize treatments for patients with persistent and/or progressive disease. Most recently, the advancement of knowledge regarding the molecular aspects of thyroid cancer has improved thyroid cancer diagnosis and has enabled individualized therapeutic options for selected patients with the most aggressive forms of the disease. Guidelines from multiple societies across the world reflect these changes, which focus on taking a more individualized approach to clinical management. In this review, we discuss the current more personalized approach to patients with follicular cell-derived thyroid cancer and point toward areas of future research still needed in the field.

Differentiated Thyroid Cancer: A Health Economic Review

Simple Summary

This review reflects on health economic considerations associated with the increasing diagnosis and treatment of differentiated thyroid cancer. Analysis of different relevant health economic topics, such as overdiagnosis, overtreatment, surgical costs, and costs of follow-up are being addressed. Several unanswered research questions such as optimising molecular markers for diagnosis, active surveillance of primary tumours, and improved risk stratification and survivorship care all influence future healthcare expenditures.

Abstract

The incidence of differentiated thyroid cancer (DTC) is rising, mainly because of an increased detection of asymptomatic thyroid nodularity revealed by the liberal use of thyroid ultrasound. This review aims to reflect on the health economic considerations associated with the increasing diagnosis and treatment of DTC. Overdiagnosis and the resulting overtreatment have led to more surgical procedures, increasing health care and patients’ costs, and a large pool of community-dwelling thyroid cancer follow-up patients. Additionally, the cost of thyroid surgery seems to increase year on year even when inflation is taken into account. The increased healthcare costs and spending have placed significant pressure to identify potential factors associated with these increased costs. Some truly ground-breaking work in health economics has been undertaken, but more cost-effectiveness studies and micro-cost analyses are required to evaluate expenses and guide future solutions.

Protocol for a Korean Multicenter Prospective Cohort Study of Active Surveillance or Surgery (KoMPASS) in Papillary Thyroid Microcarcinoma

BACKGROUND

A Korean Multicenter Prospective cohort study of Active Surveillance or Surgery (KoMPASS) for papillary thyroid microcarcinomas (PTMCs) has been initiated. The aim is to compare clinical outcomes between active surveillance (AS) and an immediate lobectomy for low-risk PTMCs. We here outline the detailed protocol for this study.

METHODS

Adult patients with a cytopathologically confirmed PTMC sized 6.0 to 10.0 mm by ultrasound (US) will be included. Patients will be excluded if they have a suspicious extra-thyroidal extension or metastasis of a PTMC or multiple thyroid nodules or other thyroid diseases which require a total thyroidectomy. Printed material describing the prognosis of PTMCs, and the pros and cons of each management option, will be provided to eligible patients to select their preferred intervention. For the AS group, thyroid US, thyroid function, and quality of life (QoL) parameters will be monitored every 6 months during the first year, and then annually thereafter. Disease progression will be defined as a ≥3 mm increase in maximal diameter of a PTMC, or the development of new thyroid cancers or metastases. If progression is detected, patients should undergo appropriate surgery. For the lobectomy group, a lobectomy with prophylactic central neck dissection will be done within 6 months. After initial surgery, thyroid US, thyroid function, serum thyroglobulin (Tg), anti-Tg antibody, and QoL parameters will be monitored every 6 months during the first year and annually thereafter. Disease progression will be defined in these cases as the development of new thyroid cancers or metastases.

CONCLUSION

KoMPASS findings will help to confirm the role of AS, and develop individualized management strategies, for low-risk PTMCs.

Clinical management of low-risk papillary thyroid microcarcinoma

Papillary thyroid microcarcinoma (PTMC) is well known to have an indolent nature with an excellent prognosis. Surgery has been the standard treatment during the past several decades, with metastasis or recurrence being exceedingly rare. Active surveillance (AS) is a new risk-adapted approach alternative to surgery that involves just watching, but not giving any treatment unless needed, not addressing the tumor itself. The patients for whom AS is adopted spend their time "with tumors." In follow-up, it is possible that alarming factors such as tumor progression appear, causing anxiety about progression. Furthermore, endless follow-up is needed. However, considering the indolent nature and unfavorable events such as surgical complications caused by surgery, AS is a good management plan for selected PTMC patients. Decision making balancing between the prognosis and unfavorable events is needed for the treatment plan. Consideration of the factors and timing of surgical conversion is also needed. In this review article, how AS should be adopted as a new management option that is an alternative to surgery, which has been the absolute choice of treatment up to recently, is discussed. Concurrently, the characteristics of the two treatment strategies are reviewed, while introducing the background that explains how AS came to attention.

Active Surveillance of Thyroid Microcarcinoma-Can This Approach Be Safely Implemented Worldwide?

The incidence of thyroid cancer has been increasing exponentially worldwide, mainly due to increased detection of small papillary thyroid microcarcinomas (PTMCs). Given the indolent nature of the disease, active surveillance (AS) has been suggested as an alternative approach to immediate surgery in the management of low-risk PTMCs. The decision to proceed with AS must take into account patient characteristics, tumor characteristics, and medical team characteristics. In this review, we discuss the rationale and evidence to support AS, as well as important considerations and limitations to implementing this approach for PTMC worldwide.

Active surveillance for low-risk small papillary thyroid cancer in North American countries: past, present and future (bridging the gap between North American and Asian practices)

Papillary thyroid cancer (PTC) is increasingly being diagnosed worldwide; yet the mortality remains very low, suggesting widespread overdiagnosis. While traditional management of PTC includes thyroid surgery, sometimes followed by radioactive iodine treatment, there is a global trend towards more conservative approaches for patients who are considered as the lowest risk of recurrence or death from their disease. Active surveillance (AS), once called watchful waiting, involves close follow-up, with the intention to intervene if the cancer progresses, or on patient request. The Kuma Hospital in Japan was the first to introduce AS as an alternative to immediate thyroid surgery for low-risk papillary thyroid microcarcinomas (PTMC, <1 cm) in 1993. Accumulated evidence over the years has shown that AS is a safe and effective approach in select patients, with a low rate of cancer progression during AS. Consequently, the Japanese Clinical Guidelines for treatment of thyroid tumor approved AS as a first-line management for patients with asymptomatic PTMC in 2010. Subsequently, the latest 2015 American Thyroid Association guidelines endorsed AS as an alternative approach to immediate surgery for cytologically confirmed very low-risk PTC. However, the acceptance, feasibility and results of AS in patients with low-risk PTC outside of Japan are still largely unknown. Most guidelines recommend that thyroid nodules <1 cm should not be aspirated but instead monitored regardless of the ultrasonographic characteristics. In essence, these patients are also being subjected to AS. Specific recommendations and the role of molecular testing for the optimal selection of PTMC patients for an AS management approach are not well established. Furthermore, research is needed to assess the long-term clinical and psychosocial outcomes in patients with larger tumor sizes (>1 cm) who undergo screening and diagnosis according to the North American guidelines and practices. The first Canadian prospective observational study launched in 2016 is intended to complement the existing data for AS of small low-risk PTC (≤2 cm) and may provide insight into the different approaches in North American and Asian practices. This review intends to summarize the development and the rationale of AS for PTMC and highlights significant differences between North American and Japanese practices.

Active surveillance of low-risk papillary thyroid microcarcinomas

In 1993, active surveillance of low-risk papillary thyroid microcarcinomas (PTMCs) started in Kuma Hospital, Kobe, Japan. It has spread globally after the publishing of American Thyroid Association (ATA) guidelines. During our hospital's active surveillance program, few patients (8.0%) showed tumor size enlargement ≥3 mm or the new appearance of node metastasis (3.8%) at 10-year follow-up. Conversion surgery was recommended for patients with disease progression. To date, no patients showed significant recurrence or metastasis or died with thyroid carcinoma when patients underwent active surveillance or after surgery due to PTMC progression. Unlike clinical papillary thyroid carcinoma (PTC), elderly patients' PTMCs were less progressive compared to those of young and middle-aged patients, indicating that elderly patients are strong candidates for the active surveillance of their PTMC. Although young patients' PTMCs are the most progressive, >50% and >75% of patients in their 20s and 30s would avoid conversion surgical treatment in their lifetime, respectively (according to estimated lifetime probability), indicating that such young patients are still candidates for active surveillance. It can thus be concluded that active surveillance is appropriate to be first management for PTMCs, based on the accumulation of favorable outcomes of PTMC patients who have undergone active surveillance, as well as the lower incidences of unfavorable events and lower medical cost than immediate surgery.

Cost-effectiveness of fiberoptic laryngoscopy prior to total thyroidectomy for low-risk thyroid cancer patients

BACKGROUND

Flexible fiberoptic laryngoscopy is performed prior to thyroid surgery to evaluate the function of the recurrent laryngeal nerve. We assess the cost-effectiveness of preoperative laryngoscopy prior to total thyroidectomy for a low-risk thyroid cancer patient without dysphonia.

METHODS

A decision tree analysis was performed from a third-party payer perspective. We assessed the cost-effectiveness of fiberoptic laryngoscopy prior to total thyroidectomy for T2N0M0 papillary thyroid carcinoma, such that an ipsilateral vocal fold paralysis alters the surgical plan to hemi-thyroidectomy, when permissible, to avoid the risk of bilateral vocal fold paralysis.

RESULTS

Performing preoperative laryngoscopy to assess vocal fold function has an incremental cost-effectiveness ratio (ICER) of 45 193 USD/QALY compared to no laryngoscopy. At a willingness-to-pay of 100 K/QALY, the intervention is cost-effective if the incidence of vocal fold paralysis is at least 0.57%, or when the permissible rate of hemithyroidectomy in cases of incidental paralysis is at least 41%. Probabilistic sensitivity analysis shows that laryngoscopy is cost-effective in 90.9% of cases.

CONCLUSIONS

Fiberoptic laryngoscopy is a cost-effective prior to total thyroidectomy in asymptomatic, low-risk thyroid cancer patients.

US-guided Microwave Ablation of Low-Risk Papillary Thyroid Microcarcinoma: Longer-Term Results of a Prospective Study

BACKGROUND

Papillary thyroid microcarcinoma (PTMC) has become a main cause of the extremely high incidence of thyroid carcinoma. This study aimed to evaluate the longer-term effectiveness of ultrasound (US)-guided microwave ablation (MWA) for treatment of low-risk PTMC with a large population.

METHODS

This prospective study was approved by ethics committee of our institution. MWA was performed under US-guidance for 119 unifocal PTMC patients without clinically cervical or distant metastasis. The target ablation zone exceeded the tumor edge judged by contrast-enhanced US to avoid marginal residue and recurrence. US and thyroid function evaluation were followed at 1, 3, 6, and 12 months after treatment and every 6 to 12 months thereafter. Any adverse event associated with MWA was evaluated.

RESULTS

The follow-up duration after MWA was 37.2 ± 20.9 months (range 12-101 months). Tumor volume decreased significantly from 1.87 ± 1.03 mL immediately after MWA to 0.01 ± 0.04 mL at the final evaluation (P < 0.001), with a mean volume reduction ratio of 99.4 ± 2.2% and 107 cases (93.9%) got complete remission. A patient was detected with cervical lymph node metastasis at 26-month follow-up and underwent 1 additional MWA treatment successfully. No distant metastasis was observed. All the acquired histological pathology results confirmed the absence of residual or recurrent tumor cells after MWA. No delayed complications associated with MWA were encountered for all patients.

CONCLUSIONS

Percutaneous MWA is technically feasible for complete PTMC destruction and showed well longer-term effectiveness; thus, it seems to be an effective nonsurgical therapy to complement the current recommendation for selected low-risk PTMC patients.

The American Association of Endocrine Surgeons Guidelines for the Definitive Surgical Management of Thyroid Disease in Adults

OBJECTIVE

To develop evidence-based recommendations for safe, effective, and appropriate thyroidectomy.

BACKGROUND

Surgical management of thyroid disease has evolved considerably over several decades leading to variability in rendered care. Over 100,000 thyroid operations are performed annually in the US.

METHODS

The medical literature from 1/1/1985 to 11/9/2018 was reviewed by a panel of 19 experts in thyroid disorders representing multiple disciplines. The authors used the best available evidence to construct surgical management recommendations. Levels of evidence were determined using the American College of Physicians grading system, and management recommendations were discussed to consensus. Members of the American Association of Endocrine Surgeons reviewed and commented on preliminary drafts of the content.

RESULTS

These clinical guidelines analyze the indications for thyroidectomy as well as its definitions, technique, morbidity, and outcomes. Specific topics include Pathogenesis and Epidemiology, Initial Evaluation, Imaging, Fine Needle Aspiration Biopsy Diagnosis, Molecular Testing, Indications, Extent and Outcomes of Surgery, Preoperative Care, Initial Thyroidectomy, Perioperative Tissue Diagnosis, Nodal Dissection, Concurrent Parathyroidectomy, Hyperthyroid Conditions, Goiter, Adjuncts and Approaches to Thyroidectomy, Laryngology, Familial Thyroid Cancer, Postoperative Care and Complications, Cancer Management, and Reoperation.

CONCLUSIONS

Evidence-based guidelines were created to assist clinicians in the optimal surgical management of thyroid disease.

Active surveillance as a management strategy for papillary thyroid microcarcinoma

Active surveillance (AS) can be considered as a treatment strategy for low risk papillary thyroid microcarcinoma (PTMC), with the absence of clinically apparent lymph nodes, extrathyroidal extensions, and distant metastasis. After reviewing the reports on AS of low risk PTMCs worldwide, we introduced AS, and discussed the selection criteria for active surveillance candidates based on different guidelines and the follow-up schedules. Moreover, the requirement of cytological diagnosis, progression evaluation methods, necessity of thyrotropin suppression, and medical costs were issues that both clinicians and patients considered. The usefulness of AS for low risk PTMC patients depended on accurate and confidential evaluation of patient risk. Clinicians may adopt measures like dynamic monitoring, risk stratification, and making personal follow-up schedules to minimize these potential risks. By appropriately selecting PTMC patients, AS can be an effective alternative treatment to immediate surgery.

Active surveillance of low-risk papillary thyroid microcarcinomas in Japan and other countries: a review

Introduction: Active surveillance of low-risk papillary thyroid microcarcinomas (PTMCs) was initiated in Japan in 1993 and has since been adopted in many countries, especially after its approval by the American Thyroid Association in 2015.Areas covered: We performed a literature review in Medline/PubMed to identify studies that used active surveillance for PTMCs. Moreover, we performed a literature review about the increased incidence of thyroid microcarcinomas in relation to the relative stability of deaths due to thyroid carcinomas.Expert opinion: No patients showed life-threatening metastasis/recurrence or died of thyroid carcinoma during active surveillance or after conversion surgery following PTMC progression. Thus, active surveillance should be the first-line management of PTMCs without high-risk features. In the future, molecular testing of actively growing PTMCs using cytology specimens could be useful to guide the treatment plan.

Early Diagnosis of Low-Risk Papillary Thyroid Cancer Results Rather in Overtreatment Than a Better Survival

We are witnessing a rapid worldwide increase in the incidence of papillary thyroid carcinoma (PTC) in the last thirty years. Extensive implementation of cancer screening and wide availability of neck ultrasound or other imaging studies is the main reason responsible for this phenomenon. It resulted in a detection of a growing number of clinically asymptomatic PTCs, mainly low-risk tumors, without any beneficial impact on survival. An indolent nature of low-risk PTC, particularly papillary thyroid microcarcinoma (PTMC), and the excellent outcomes raise an ongoing discussion regarding the adequacy of treatment applied. The question of whether PTMC is overtreated or not is currently completed by another, whether PTMC requires any treatment. Current ATA guidelines propose less extensive preoperative diagnostics and, if differentiated thyroid cancer is diagnosed, less aggressive surgical approach and limit indications for postoperative radioiodine therapy. However, in intrathyroidal PTMCs in the absence of lymph node or distant metastases, active surveillance may constitute alternative management with a low progression rate of 1%-5% and without any increase in the risk of poorer outcomes related to delayed surgery in patients, in whom it was necessary. This review summarizes the current knowledge and future perspectives of active surveillance in low-risk PTC.

Active Surveillance of Papillary Thyroid Microcarcinoma: Where Do We Stand?

The recent sharp increase in thyroid cancer incidence is mainly due to increased detection of small papillary thyroid microcarcinoma (PTMC). Due to the indolent nature of the disease, active surveillance (AS) of low-risk PTMCs is suggested as an alternative to immediate surgery to reduce morbidity from surgery. For appropriately selected PTMC patients, AS can be a good management option and surgical intervention can be safely delayed until progression occurs. Many considerations must be taken into account at the time of initiation of AS, including radiological tumor characteristics and clinical characteristics of the patient. A specialized medical team should be assembled to monitor patients during AS with an appropriate follow-up protocol. The fact that some patients require surgery for disease progression after long-term follow-up is a major drawback of the current AS protocol. Evaluation of tumor kinetics by three-dimensional tumor volume measurement during the initial 2-3 years of AS may be helpful for discrimination of PTMCs that need early surgical intervention. In this review, we will discuss the clinical outcomes of surgical intervention and AS, considerations during AS, and unresolved questions about AS.

Health Utility Book (HUB)-Cancer: Protocol for a Systematic Literature Review of Health State Utility Values in Cancer

Background. Treatment options in oncology are rapidly advancing, and public payer systems are increasingly under pressure to adopt new but expensive cancer treatments. Cost-utility analyses (CUAs) are used to estimate the relative costs and effects of competing interventions, where health outcomes are measured using quality-adjusted life years (QALYs). Health state utility values (HSUVs) are used to reflect health-related quality of life or health status in the calculation of QALYs. To support reimbursement agencies in the appraisal of oncology drug submissions, which typically include a CUA component, we have proposed a systematic literature review of published HSUV estimates in the field of oncology. Methods. The following databases will be searched: MEDLINE, EMBASE, EconLit, and CINAHL. A team of reviewers, working independently and in duplicate, will evaluate abstracts and full-text publications for eligibility against broad inclusion criteria. Studies using a direct, indirect, or combination approach to eliciting preferences related to cancer or cancer treatments are eligible. Data extraction will capture details of study methodology, participants, health states, and corresponding HSUVs. We will summarize our findings with descriptive analyses at this stage. A pilot review in thyroid cancer is presented to illustrate the proposed methods. Discussion. This systematic review will generate a comprehensive summary of the oncology HSUV literature. As a component of the Health Utility Book (HUB) project, we anticipate that this work will assist both health economic modelers as well as critical reviewers in the development and appraisal of CUAs in oncology.

Risk-oriented concept of treatment for intrathyroid papillary thyroid cancer

Adapting treatment and follow-up according to the risk of recurrence and/or death from thyroid cancer is a relatively recent concept of "personnalized" medicine, developed particularly to avoid overtreatment of low-risk thyroid cancer which represents the majority of thyroid cancers diagnosed in the world today. For low-risk thyroid cancer, this decrease in extent of treatment involves the extent of surgery-total thyroidectomy, lobectomy or no surgery with active surveillance-but also the indications, doses and methods of stimulation when or if administering radioactive iodine (RAI), the indication for suppressive thyroxin therapy and the extent and modalities for follow-up that should be adapted to the risk of recurrence. The aim is to optimize medical resources and quality of life, particularly for low-risk patients whose life expectancy is that of the general population.

Longitudinal Assessment of Quality of Life According to Treatment Options in Low-Risk Papillary Thyroid Microcarcinoma Patients: Active Surveillance or Immediate Surgery (Interim Analysis of MAeSTro)

Background: In this ongoing multicenter prospective cohort study on active surveillance (AS) in low-risk papillary thyroid microcarcinoma (PTMC), we aimed to compare the quality of life (QoL) of participants based on their choice of treatment, that is, AS or immediate surgery (OP). Methods: QoL of 203 participants who chose AS and 192 participants who underwent OP was evaluated using a thyroid-specific QoL questionnaire at diagnosis and during follow-up (median 8 months). Results: The mean ages of the participants in the AS and OP groups were 47.3 ± 11.7 and 45.6 ± 10.5 years (p = 0.138), respectively, and the mean tumor sizes were 5.7 ± 1.6 and 6.5 ± 2.1 mm (p = 0.065), respectively. At baseline, significantly better psychological health (7.1 ± 1.3 vs. 6.8 ± 1.6, p = 0.023) and overall health (6.8 ± 1.2 vs. 6.5 ± 1.3, p = 0.018) were observed in the AS group than in the OP group. During follow-up, significantly better physical (7.9 ± 1.1 vs. 7.4 ± 1.2, p < 0.001), psychological (7.4 ± 1.3 vs. 6.9 ± 1.6, p = 0.004), and overall health (6.9 ± 1.0 vs. 6.5 ± 1.1, p = 0.002) were observed in the AS group than in the OP group, whereas spiritual health was comparable between the two groups. Compared with the AS group, the OP group experienced more fatigue, changes in voice and appearance, less satisfaction, and low fear of recurrence. The self-assessed financial burden was similar at baseline and follow-up in both groups. Conclusion: The QoL of PTMC patients is different according to the type of treatment. Better psychological health at baseline and physical and psychological health at follow-up were observed in the AS group than in the OP group. However, studies with longer follow-up periods are needed.

Active surveillance for prostate and thyroid cancers: evolution in clinical paradigms and lessons learned

The adverse effects of overdiagnosis and overtreatment observed in men with clinically insignificant prostate cancers after the introduction of prostate-specific antigen-based screening are now being observed in those with thyroid cancer, owing to the introduction of new imaging technologies. Thus, the evolving paradigm of active surveillance in prostate and thyroid cancers might be valuable in informing the development of future active surveillance protocols. The lessons learned from active surveillance and their implications include the need to minimize the use of broad, population-based screening programmes that do not incorporate patient education and the need for individualized or shared decision-making, which can decrease the extent of overtreatment. Furthermore, from the experience in patients with prostate cancer, we have learned that consensus is required regarding the optimal selection of patients for active surveillance, using more-specific evidence-based methods for stratifying patients by risk. In this Review, we describe the epidemiology, pathology and screening guidelines for the management of patients with prostate and thyroid cancers; the evidence of overdiagnosis and overtreatment; and provide overviews of existing international active surveillance protocols.

Cost for treatment and follow-up of thyroid cancer increases according to the severity of disease

BACKGROUND

The aim of this study was to provide an analysis of thyroid cancer-related health care costs over a 5-year period, according to the extent of thyroid surgery.

METHODS

The study included 33 patients from our institutional database who underwent thyroid cancer surgery in 2010. Patients were divided into four groups based on surgical extent: (1) hemithyroidectomy, (2) total thyroidectomy, (3) total thyroidectomy with ipsilateral radical neck dissection, and (4) total thyroidectomy with bilateral radical neck dissection and mediastinal dissection. Costs for admission and outpatient follow-up for 5 years were analyzed.

RESULTS

Costs for outpatient follow-up and admission, and overall cost increased with increasing stage of disease and increasing extent of thyroid surgery. Patients who underwent only hemithyroidectomy had the lowest costs for outpatient follow-up and admission, as well as the lowest overall cost.

CONCLUSION

Over the 5-year follow-up period, surgery performed at an early disease stage was the most cost-effective.

Comparison of the Efficacy of Three Different Methods of Explaining the Surgical Procedure of Hemithyroidectomy

BACKGROUND

For patients indicated for surgical treatment, adequate information about the procedure and its complications is a prerequisite for consent, reassures the patient, and allows them to make a well-informed decision. This prospective randomized study aimed to compare the outcomes of three different methods of explaining the procedure of hemithyroidectomy to patients' satisfaction.

MATERIAL AND METHODS

The three different methods for explaining the surgical procedure included a conventional diagram, three-dimensional (3D) thyroid model, and 2-minute animated video. A modified Patient Satisfaction Questionnaire was used to evaluate the efficacy of the methods and assess overall patient experience; 20 patients were randomized to each group. An endocrine surgeon performed the operative procedure using a sutureless technique. The procedure was explained to the patient a week before surgery in the outpatient department.

RESULTS

Majority of the patients were female. The most common indication for surgery was a solitary thyroid nodule. Patients who watched the animated video demonstrated significantly higher satisfaction levels and significantly lower anxiety levels than those in the other groups (P < 0.01). Patients who watched the video or who received instructions using the 3D model also reported that their information needs were met. Overall experience with the procedure and hospital stay was not significantly different between the groups.

CONCLUSION

Overall patient satisfaction for the surgical procedure was similar across the three groups. However, the animated video appeared to be a better model to explain the procedure to the patient, resulting in enhanced knowledge acquisition, reduced anxiety, and improved patient satisfaction.

Study Protocol of Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro)

BACKGROUND

The ongoing Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) aims to observe the natural course of papillary thyroid microcarcinoma (PTMC), develop a protocol for active surveillance (AS), and compare the long-term prognosis, quality of life, and medical costs between the AS and immediate surgery groups.

METHODS

This multicenter prospective cohort study of PTMC started in June 2016. The inclusion criteria were suspicious of malignancy or malignancy based on fine needle aspiration or core needle biopsy, age of ≥18 years, and a maximum diameter of ≤1 cm. If there was no major organ involvement, no lymph node/distant metastasis, and no variants with poor prognosis, the patients were explained of the pros and cons of immediate surgery and AS before selecting AS or immediate surgery. Follow-up visits (physical examination, ultrasonography, thyroid function, and questionnaires) are scheduled every 6 months during the first 2 years, and then every 1 year thereafter. Progression was defined as a maximum diameter increase of ≥3, ≥2 mm in two dimensions, suspected organ involvement, or lymph node/distant metastasis.

RESULTS

Among 439 enrolled patients, 290 patients (66.1%) chose AS and 149 patients (33.9%) chose immediate surgery. The median follow-up was 6.7 months (range, 0.2 to 11.9). The immediate surgery group had a larger maximum tumor diameter, compared to the AS group (7.1±1.9 mm vs. 6.6±2.0 mm, respectively; P=0.014).

CONCLUSION

The results will be useful for developing an appropriate PTMC treatment policy based on its natural course and risk factors for progression.

Active Surveillance of Papillary Thyroid Microcarcinoma: A Mini-Review from Korea

In Korea, the incidence of thyroid cancer increased explosively in the early 2000s, and reached a plateau in the early 2010s. Most cases of newly diagnosed thyroid cancer are small indolent microcarcinoma and could be good candidates for active surveillance (AS) instead of immediate surgery. Many considerations must be taken into account for establishing selection criteria for candidates for AS of papillary thyroid microcarcinoma (PTMC), including the characteristics of the tumor, the patient, and the medical team. If possible, AS of PTMC should be a part of a prospective clinical trial to ensure long-term safety and to identify clinical and/or molecular markers of the progression of PTMC. In this review, we discuss lessons regarding surgical interventions for PTMC, and then describe the concept, application, caveats, unanswered questions, and future perspectives of AS of PTMC. For appropriately selected patients with PTMC, AS can be a good alternative to immediate surgery.

The thyroid cancer epidemic, 2017 perspective

PURPOSE OF REVIEW

Thyroid cancer incidence and mortality trends have been identified as being consistent with overdiagnosis, and several recent efforts have been made to mitigate this problem.

RECENT FINDINGS

Major guidelines for thyroid nodule management recommend against general biopsy of nodules less than 1 cm in size. Data supporting the safety of active surveillance of low-risk thyroid cancers is now recognized. Tumors previously labeled as encapsulated follicular variant papillary thyroid cancers are now recommended to be called noninvasive follicular thyroid neoplasm with papillary-like nuclear features.

SUMMARY

Workup, diagnostic, and management of papillary thyroid cancer are changing rapidly to accommodate the recognition that many thyroid cancers are low risk and do not require aggressive, immediate intervention.

Controversies in the Management of Low-Risk Differentiated Thyroid Cancer

Controversy exists over optimal management of low-risk differentiated thyroid cancer. This controversy occurs in all aspects of management, including surgery, use of radioactive iodine for remnant ablation, thyroid hormone supplementation, and long-term surveillance. Limited and conflicting data, treatment paradigm shifts, and differences in physician perceptions contribute to the controversy. This lack of physician consensus results in wide variation in patient care, with some patients at risk for over- or undertreatment. To reduce patient harm and unnecessary worry, there is a need to design and implement studies to address current knowledge gaps.

Indolent thyroid cancer: knowns and unknowns

Thyroid cancer incidence is rapidly increasing due to increased detection and diagnosis of indolent thyroid cancer, i.e. cancer that is likely to be clinically insignificant. Clinical, radiologic, and pathologic features predicting indolent behavior of thyroid cancer are still largely unknown and unstudied. Existing clinicopathologic staging systems are useful for providing prognosis in the context of treated thyroid cancer but are not designed for and are inadequate for predicting indolent behavior. Ultrasound studies have primarily focused on discrimination between malignant and benign nodules; some studies show promising data on using sonographic features for predicting indolence but are still in their early stages. Similarly, molecular studies are being developed to better characterize thyroid cancer and improve the yield of fine needle aspiration biopsy, but definite markers of indolent thyroid cancer have yet to be identified. Nonetheless, active surveillance has been introduced as an alternative to surgery in the case of indolent thyroid microcarcinoma, and protocols for safe surveillance are in development. As increased detection of thyroid cancer is all but inevitable, increased research on predicting indolent behavior is needed to avoid an epidemic of overtreatment.