Decreasing Use of Radioactive Iodine for Low-Risk Thyroid Cancer in California, 1999 to 2015

Practice patterns in management of differentiated thyroid cancer since the 2014 British Thyroid Association (BTA) guidelines

BACKGROUND

The updated 2014 BTA guidelines emphasised a more conservative, risk adapted model for the management of low-risk differentiated thyroid cancer (DTC). In comparison to historical approach of total thyroidectomy combined with radioactive iodine, treatment de-escalation is increasingly supported.

AIMS

To evaluate the impact of the updated BTA guidelines on the management of DTC cases at regional UK centre.

METHODS

All DTC patients were retrospectively identified from regional thyroid MDT database between Jan2009-Dec2020. Oncological treatment and clinico-pathological characteristics were analysed.

RESULTS

623 DTC cases were identified; 312 (247 female: 65 male) between 2009 and 2014 and 311 (225 female: 86 male) between 2015 and 2020. Median age is 48 years (range 16-85). By comparing pre- and post-2015 cohorts, there was a significant drop in total thyroidectomy (87.1% vs 76.8%, p = 0.001) and the use of radioactive iodine (RAI) (73.1% vs 62.1%, p = 0.003) in our post-2015 cohort. When histological adverse features were analysed, extra-thyroidal extension (4.2% vs 17.0%, p=< 0.001), lymphovascular invasion (31.4% vs 50.5%, p=<0.001) and multi-centricity (26.9% vs 43.4%, p = 0.001) were significantly increased in the post 2015 cohort. Nonetheless, total thyroidectomy (TT) remains the treatment choice for low risk T1/2 N0 M0 disease in 65.3% (124/190) in post-2015 cohort for several reasons. Reasons include adverse histological features (50.8%), benign indications (32.5%), contralateral nodules (11.7%), patient preference (2.5%), and diagnostic uncertainty (2.5%).

CONCLUSION

Our study confirms a move towards a more conservative approach to patients with low-risk DTC in the UK, which is in keeping with the BTA 2014 guideline and international trends, but total thyroidectomy remains prevalent for low risk T1/2 N0 M0 disease for other reasons.

Disparities in Initial Thyroid Cancer Care by Hospital Treatment Volume: Analysis of 52,599 Cases in California

Background: Racially minoritized patients with thyroid cancer are less likely to receive high-quality and guideline-concordant care. Inaccessibility of high-volume centers may contribute to inequalities in thyroid cancer outcomes. This study sought to understand the extent to which access to higher volume thyroid cancer centers is associated with patient outcomes. Methods: We queried linked California Cancer Registry and California Office of Statewide Health Planning and Development databases for thyroid cancer patients who received thyroid surgery between 1999 and 2017. Hospitals were stratified by their median annual volume of thyroid cancer operations: ultra-low volume (0-5 cases/year), low-volume (6-25 cases/year), mid-volume (26-50 cases/year), and high-volume (>50 cases/year). We analyzed the rates of complications, rates of reoperation for cancer recurrence, use of radioactive iodine (131I), and mortality by median hospital volume of thyroid surgery. A multivariable regression controlled for high-risk tumor features. Differences in access by center volume were assessed based on patient demographics. Results: We studied 52,599 thyroid cancer patients who underwent thyroidectomy. Patients who underwent thyroidectomy at ultra-low volume centers were more likely to undergo reoperations for recurrent/persistent disease compared with patients at low- (odds ratio [OR] 1.17 [CI 1.02-1.35]), mid- (OR 1.25 [CI 1.06-1.46]), and high-volume centers (OR 1.26 [CI 1.03-1.56]). Patients who received thyroid operations at ultra-low volume centers were also less likely to receive guideline-concordant 131I ablation compared with patients at higher volume centers (OR 0.77 [CI 0.72-0.82]). A pair-wise comparison between all volume categories for all outcomes revealed no statistically significant differences in outcomes between low-, mid-, or high-volume centers. Only ultra-low volume centers had significantly higher rates of adverse outcomes. Ultra-low volume centers were disproportionately accessed by women (p < 0.05), Hispanic, Asian/Pacific Islander, and American Indian people (p < 0.01), those from the lowest three quintiles of socio-economic status (p < 0.01), and the uninsured and those on Medicaid or Medicare (p < 0.01) when compared with higher volume centers. Conclusions: Patients receiving thyroid cancer surgery at centers performing ≤5 such operations per year were more likely to require reoperation for recurrent/persistent disease and less likely to receive appropriate 131I ablation. Ultra-low volume centers served higher proportions of socially and economically marginalized communities.

Radioactive Iodine: A Living History

Background: Before the development of antithyroid drugs in the 1940s, treatment of Graves' hyperthyroidism was primarily surgical. Surgical mortality was quite variable, but a significant minority of patients died during or after surgery. Summary: In 1936, Karl Compton, President of the Massachusetts Institute of Technology, in a lecture attended by Massachusetts General Hospital physicians, suggested that artificially radioactive isotopes might be useful for studying metabolism. By 1942, Hertz and Roberts reported on the successful use of radioactive iodine (RAI) to treat Graves' hyperthyroidism. RAI uptake was subsequently demonstrated in well-differentiated thyroid cancer metastases. In 1948, Seidlin demonstrated stimulation of uptake in thyroid cancer metastases by thyrotropin (TSH). By 1990, 69% of endocrinologists in North America recommended RAI for Graves' hyperthyroidism. Currently RAI is less frequently used for Graves' hyperthyroidism, related to concerns about exacerbation of thyroid eye disease, about radiation exposure, and about potential adverse consequences of permanent hypothyroidism. Similarly, RAI was administered to the majority of patients with thyroid cancer for decades, but its use is now more selective. Conclusions: RAI is a remarkable example of interinstitutional cooperation between physicians and scientists to transition from bench to bedside in only three years. It is the model for a theranostic approach to disease (the simultaneous use of a radioactive drug for diagnosis and therapy). The future of RAI is less certain; inhibition of TSH receptor stimulating antibodies in Graves' disease and more precise targeting of genes that drive thyroid oncogenesis may diminish the use of RAI. Alternatively, redifferentiation techniques may improve the efficacy of RAI in RAI-refractory thyroid cancer.

Progress and Challenges in Thyroid Cancer Management

The state of thyroid cancer in 2021 is reviewed including the prevalence of thyroid cancer, vulnerable patient groups such as women and young adults, and known and hypothesized risk factors for thyroid cancer. Understanding the overdiagnosis and overtreatment of thyroid cancer and recent efforts to reduce harms secondary to overdiagnosis and overtreatment are addressed with optimism that future work will continue to evaluate and improve the care of patients with thyroid cancer.

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.

Multilevel Factors Associated With More Intensive Use of Radioactive Iodine for Low-Risk Thyroid Cancer

CONTEXT

The use of radioactive iodine (RAI) for low-risk thyroid cancer is common, and variation in its use exists, despite the lack of benefit for low-risk disease and potential harms and costs.

OBJECTIVE

To simultaneously assess patient- and physician-level factors associated with patient-reported receipt of RAI for low-risk thyroid cancer.

METHODS

This population-based survey study of patients with newly diagnosed differentiated thyroid cancer identified via the Surveillance Epidemiology and End Results (SEER) registries of Georgia and Los Angeles County included 989 patients with low-risk thyroid cancer, linked to 345 of their treating general surgeons, otolaryngologists, and endocrinologists. We assessed the association of physician- and patient-level factors with patient-reported receipt of RAI for low-risk thyroid cancer.

RESULTS

Among this sample, 48% of patients reported receiving RAI, and 23% of their physicians reported they would use RAI for low-risk thyroid cancer. Patients were more likely to report receiving RAI if they were treated by a physician who reported they would use RAI for low-risk thyroid cancer compared with those whose physician reported they would not use RAI (adjusted OR: 1.84; 95% CI, 1.29-2.61). The odds of patients reporting they received RAI was 55% lower among patients whose physicians reported they saw a higher volume of patients with thyroid cancer (40+ vs 0-20) (adjusted OR: 0.45; 0.30-0.67).

CONCLUSIONS

Physician perspectives and attitudes about using RAI, as well as patient volume, influence RAI use for low-risk thyroid cancer. Efforts to reduce overuse of RAI in low-risk thyroid cancer should include interventions targeted toward physicians, in addition to patients.

Risk and outcome of subsequent malignancies after radioactive iodine treatment in differentiated thyroid cancer patients

BACKGROUND

We identified differentiated thyroid cancer (DTC) survivors from SEER registries and performed Poisson regression to calculate the relative risks (RRs) of subsequent malignancies (SMs) by different sites associated with radioactive iodine (RAI) treatment, and the attributable risk proportion of RAI for developing different SMs.

RESULTS

We identified 4628 of 104,026 DTC patients developing a SM after two years of their DTC diagnosis, with a medium follow-up time of 113 months. The adjusted RRs of developing SM associated with RAI varied from 0.98 (0.58-1.65) for neurologic SMs to 1.37 (1.13-1.66) for hematologic SMs. The RRs of developing all cancer combined SMs generally increased with age at DTC diagnosis and decreased with the latency time. We estimated that the attributable risk proportion of RAI treatment is only 0.9% for all cancer combined SMs and 20% for hematologic SMs, which is the highest among all SMs. The tumor features and mortalities in patients treated with and without RAI are generally comparable.

CONCLUSION

With the large population based analyses, we concluded that a low percentage of DTC survivors would develop SMs during their follow-up. Although the adjusted RR of SMs development increased slightly in patients receiving RAI, the attributable risk proportion associated with RAI was low, suggesting the absolute number of SMs induced by RAI in DTC survivors would be low. The attributable risk proportion of RAI treatment is the highest in hematological SMs, but when in consideration of its low incidence among all DTC survivors, the absolute number of hematological SMs was low.

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

Objectives

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

Methods

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

Results

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

Conclusion

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

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

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Most patients were diagnosed with localized PTC.

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

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

Changes in Population-Level and Institutional-Level Prescribing Habits of Radioiodine Therapy for Papillary Thyroid Cancer

Background: In the past two decades, new evidence and guidelines have emerged to refine recommendations for the use of radioactive iodine (RAI) therapy after thyroidectomy for cancer. We aim to describe national trends in RAI utilization, assess the impact of individual hospitals on RAI utilization, and examine whether variation in prescribing habits has declined over time. Methods: The National Cancer Database (NCDB) was queried from 2004 to 2016 for patients with papillary thyroid cancer (PTC) who received total thyroidectomy. Trends were analyzed using Joinpoint analysis. Hospital-specific effects and variation in prescribing habits were assessed through a hierarchical, mixed regression model. Results: RAI utilization declined from 61.0% in 2004 to 43.9% in 2016. RAI use declined most profoundly in patients with T1a, N0/X, M0 PTC without extrathyroidal extension (34.8% in 2004 to 9.5% in 2015), but continues to be used commonly in patients with advanced disease for whom it is routinely recommended (73.4% in 2004 to 72.0% in 2015). Furthermore, ∼80% of hospitals in 2016 utilized at or below the median utilization rate in 2006. Variation in RAI utilization across hospitals decreased by ∼50% from 2004 to 2016 (Levene's test p < 0.001), with a significant decline (p = 0.002) in the variation after 2012 (confidence interval: 2010 to 2014). Conclusions: Recommendations for whom to prescribe RAI appear to have impacted both the number of patients receiving RAI and the variation in prescribing habits across hospitals. Hospital selection has contributed less to the probability of receiving RAI over time.

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.

Salivary and lacrimal dysfunction after radioactive iodine for differentiated thyroid cancer: American Head and Neck Society Endocrine Surgery Section and Salivary Gland Section joint multidisciplinary clinical consensus statement of otolaryngology, ophthalmology, nuclear medicine and endocrinology

BACKGROUND

Postoperative radioactive iodine (RAI) administration is widely utilized in patients with differentiated thyroid cancer. While beneficial in select patients, it is critical to recognize the potential negative sequelae of this treatment. The prevention, diagnosis, and management of the salivary and lacrimal complications of RAI exposure are addressed in this consensus statement.

METHODS

A multidisciplinary panel of experts was convened under the auspices of the American Head and Neck Society Endocrine Surgery and Salivary Gland Sections. Following a comprehensive literature review to assess the current best evidence, this group developed six relevant consensus recommendations.

RESULTS

Consensus recommendations on RAI were made in the areas of patient assessment, optimal utilization, complication prevention, and complication management.

CONCLUSION

Salivary and lacrimal complications secondary to RAI exposure are common and need to be weighed when considering its use. The recommendations included in this statement provide direction for approaches to minimize and manage these complications.

Looking under the hood of "the Cadillac of cancers:" radioactive iodine-related craniofacial side effects among patients with thyroid cancer

PURPOSE

Despite having a generally favorable prognosis, differentiated thyroid cancer is known to have a significant, long-term impact on the quality of life of survivors. We wished to investigate short- and long-term effects among thyroid cancer survivors following radioactive iodine therapy.

METHODS

We conducted eight focus groups (N = 47) to understand patients' experiences of short- and long-term effects after radioactive iodine treatment and the impact these treatment-related side effects had on patients' quality of life. We elicited responses regarding experiences with side effects following radioactive iodine treatment, particularly salivary, lacrimal, and nasal symptoms. We transcribed audiotapes and conducted qualitative analyses to identify codes and themes.

RESULTS

We identified eight broad themes from the qualitative analyses. Themes reflecting physical symptoms included dry mouth, salivary gland dysfunction, altered taste, eye symptoms such as tearing or dryness, and epistaxis. Psychosocial themes included lack of knowledge and preparation for treatment, regret of treatment, and distress that thyroid cancer is labeled as a "good cancer."

CONCLUSIONS

Thyroid cancer survivors reported a wide range of radioactive iodine treatment-related effects and psychosocial concerns that appear to reduce quality of life. The psychosocial concerns reported by participants underscore the significant unmet information and support needs prior to and following RAI treatment among individuals diagnosed with thyroid cancer.

IMPLICATIONS FOR CANCER SURVIVORS

Future research is needed to help both patients and physicians understand the effect of radioactive iodine on quality of life, and to better assess the benefits versus the risks of radioactive iodine therapy.

The role of radioactive iodine in the management of patients with differentiated thyroid cancer - An oncologic surgical perspective

With improved understanding of the biology of differentiated thyroid carcinoma its management is evolving. The approach to surgery for the primary tumour and elective nodal surgery is moving from a "one-size-fits-all" recommendation to a more personalised approach based on risk group stratification. With this selective approach to initial surgery, the indications for adjuvant radioactive iodine (RAI) therapy are also changing. This selective approach to adjuvant therapy requires understanding by the entire treatment team of the rationale for RAI, the potential for benefit, the limitations of the evidence, and the potential for side-effects. This review considers the evidence base for the benefits of using RAI in the primary and recurrent setting as well as the side-effects and risks from RAI treatment. By considering the pros and cons of adjuvant therapy we present an oncologic surgical perspective on selection of treatment for patients, both following pre-operative diagnostic biopsy and in the setting of a post-operative diagnosis of malignancy.

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.

Patient-Perceived Lack of Choice in Receipt of Radioactive Iodine for Treatment of Differentiated Thyroid Cancer

PURPOSE

For many patients with differentiated thyroid cancer, use of radioactive iodine (RAI) does not improve survival or reduce recurrence risk. Yet there is wide variation in RAI use, emphasizing the importance of understanding patient perspectives regarding RAI decision making.

PATIENTS AND METHODS

All eligible patients diagnosed with thyroid cancer from 2014 to 2015 from the Georgia and Los Angeles SEER registries were surveyed (N = 2,632; response rate, 63%). Patients in whom selective RAI use is recommended were included in this analysis (n = 1,319). Patients were asked whether they felt like they had a choice to receive RAI (yes or no), how strongly their physician recommended RAI (5-point Likert-type scale), whether they received RAI (yes or no), and how satisfied they were with their RAI decision (more [score of 4 or greater] v less). Multivariable, weighted logistic regression with multiple imputation was used to assess the associations between patient characteristics and perception of no RAI choice and between perception of no RAI choice with receipt of RAI and decision satisfaction.

RESULTS

More than half of respondents (55.8%) perceived they did not have an RAI choice, and the majority of patients (75.9%) received RAI. The odds of perceiving no RAI choice was greater among those whose physician strongly recommended RAI (adjusted odds ratio [OR], 1.56; 95% CI, 1.13 to 2.17). Patients who perceived they did not have an RAI choice were more likely to receive RAI (adjusted OR, 2.50; 95% CI, 1.64 to 3.82) and report lower decision satisfaction (adjusted OR, 2.31; 95% CI, 1.67 to 3.20).

CONCLUSION

Many patients did not feel they had a choice about whether to receive RAI. Patients who perceived they did not have a choice were more likely to receive RAI and report lower decision satisfaction, suggesting a need for more shared decision making to reduce overtreatment.

The efficacy of radioactive iodine for the treatment of well-differentiated thyroid cancer with distant metastasis

Objective

Radioactive iodine (¹³¹I) has been used as a treatment for high-risk well-differentiated thyroid cancer after thyroidectomy. The aim of this study was to evaluate the long-term follow-up results after using high accumulated doses of ¹³¹I (>600 mCi) for the treatment of well-differentiated thyroid cancer.

Patients and methods

In this study, we retrospectively evaluated prospectively enrolled patients with well-differentiated thyroid cancer who were treated and followed up in Chang Gung Memorial Hospital in Linkou and Keelung, Taiwan. All the patients underwent thyroidectomy between 1979 and 2016.

Results

For our study, 228 patients with papillary and follicular thyroid carcinoma with distant metastases were enrolled. Of the 228 patients, 71 (31.1%) received ¹³¹I therapy with an accumulated dose of at least 600 mCi. Forty-four died because of disease-specific mortality (DSM) after a mean follow-up of 10.6±6.3 years. Compared with the patients in the DSM group, which included 27 survival cases, patients who were younger, and those with a multifocal tumor, more extensive thyroidectomy, and papillary thyroid carcinoma showed better prognosis. The DSM group included a higher percentage of patients who developed a secondary primary cancer after receiving a diagnosis of thyroid cancer than the survival group (18.2 vs. 3.7%). However, the difference did not reach statistical significance (P=0.075).

Conclusion

¹³¹I provided an effective therapeutic modality for well-differentiated thyroid cancer patients with distant metastasis. After a mean of follow-up 10 years, more than 60% of cases resulted in DSM when high accumulated ¹³¹I doses were administered.

Predictors of Neck Reoperation and Mortality After Initial Total Thyroidectomy for Differentiated Thyroid Cancer

BACKGROUND

In an era of rising differentiated thyroid cancer incidence, the rate and impact of neck reoperation may inform the intensity of earlier interventions and surveillance. This study sought to define predictors of neck reoperation and to assess its impact on survival.

METHODS

Using the California Cancer Registry linked to the California Office of Statewide Health Planning and Development records, a retrospective cohort study was performed of 24,230 patients with total or near-total thyroidectomy for papillary or follicular thyroid cancer between 1991 and 2008 and follow-up through 2013. The primary outcome was neck reoperation 91 days to 5 years after the initial thyroid surgery. Using logistic and Cox proportional hazards regression, the impact of sociodemographics, tumor staging, and hospital thyroid cancer surgery volume on neck reoperation and survival was determined.

RESULTS

Neck reoperation was identified in 1231 (5.1%) patients in increasing odds from 1991 to 2008. In multivariable models, male sex, papillary thyroid cancer, and advancing tumor stage were associated with neck reoperation. Among men, neck reoperation was associated with Asian/Pacific Islander (odds ratio [OR] = 1.44 [confidence interval (CI) 1.07-1.94]) race/ethnicity. Among women, neck reoperation was associated with younger age (15-34 years; OR = 1.50 [CI 1.17-1.92] versus ≥55 years), and Asian/Pacific Islander (OR = 1.24 [CI 1.02-1.51]) or Hispanic (OR = 1.20 [CI 1.00-1.44]) race/ethnicity. After controlling for baseline characteristics, neck reoperation predicted worse thyroid cancer-specific survival (hazard ratio = 4.26 [CI 3.50-5.19]). The effect differed between men and women, and was most pronounced among women who received radioiodine in initial treatment (hazard ratio = 8.32 [CI 6.14-11.27]).

CONCLUSIONS

Neck reoperation is becoming increasingly frequent and is strongly predictive of mortality. Advancing tumor stage, Asian/Pacific Islander race/ethnicity, male sex, as well as younger age and Hispanic ethnicity among women predict a higher risk for neck reoperation and subsequent mortality, reflecting a higher risk of persistent or more biologically aggressive disease.