Trends in thyroid cancer incidence in Texas from 1995 to 2008 by socioeconomic status and race/ethnicity

Targeting CHEK1: Ginsenosides-Rh2 and Cu2O@G-Rh2 nanoparticles in thyroid cancer

Thyroid cancer (THCA) is an increasingly common malignant tumor of the endocrine system, with its incidence rising steadily in recent years. For patients who experience recurrence or metastasis, treatment options are relatively limited, and the prognosis is poor. Therefore, exploring new therapeutic strategies has become particularly urgent. This study confirmed that effective suppression of THCA cell proliferation and stimulation of apoptosis can be achieved through the application of Ginsenosides-Rh2. Through network pharmacology screening, the molecular target of Ginsenosides-Rh2 in THCA was identified as CHEK1, and its inhibitory effect was confirmed by downregulating CHEK1 protein expression. Furthermore, demonstrations conducted both in vitro and in vivo showcased that delivering Ginsenosides-Rh2 using nanoparticle carriers significantly reduced cell viability by approximately 50%, regulated DNA damage levels, apoptosis-related protein expression, and cell cycle control. The IC50 of the nanoparticle formulation was determined (B-CPAP IC50 = 88.24 μM), TPC IC50 = 79.52 μM). This study confirmed that Cu2O@G-Rh2 is effective in suppressing tumors and exhibits a significant inhibitory effect on tumor recurrence and metastasis while maintaining good safety. Cu2O@G-Rh2 nanoparticles possess excellent stability and anti-tumor efficacy. This research offers new perspectives for the treatment of THCA and demonstrates potential clinical applications.

Global burden of disease study analysis of thyroid cancer burden across 204 countries and territories from 1990 to 2019

Background

The purpose of this study is to assess the burden of thyroid cancer over the course of 30 years in 204 countries and territories.

Methods

Data from the Global Burden of Disease (GBD) 2019 database was analyzed to extract information on prevalence, deaths, DALYs(disability-adjusted life-years), YLL(years of life los), YLD(years lived with disability), and their corresponding age-standardized rates at global, regional, and national levels. The primary focus of the study was to examine trends in thyroid cancer from 1990 to 2019, specifically looking at the Estimated Annual Percentage Change (EAPC) for ASPR, ASDR, and ASDR. Additionally, the study investigated the relationship between cancer burden and the Socio-Demographic Index (SDI).

Results

Globally, there will be approximately 18.3 million thyroid cancer (TC) cases in 2019; China and the USA are projected to be the most significant with 310,327 and 220,711 cases (16.17 and 14.82 cases per 100,000 people, respectively).Over the period from 1990 to 2019, age-standardized prevalence rates exhibited a global rise, whereas deaths and DALYs saw a decrease(EAPC:1.63, -0.15- -0.14, respectively). Significantly, the age-standardized prevalence rate increased in 21 GBD regions, affecting 195 out of 204 countries or territories. Over the studied period, thyroid cancer cases, deaths, and DALYs were consistently higher among females than males. Furthermore, a higher Socio-demographic Index was associated with increased age-standardized prevalence rates.

Social Vulnerability Association with Thyroid Cancer Disparities in the United States

Background: As thyroid cancer incidence rises, it is increasingly valuable to recognize disparities in treatment and diagnosis. Prior investigations into social determinants of health (SDoH) are limited to pediatric populations or studies looking at single factors such as race or environmental influences. Utilizing the CDC-social vulnerability index and SEER-patient database to assess the amalgamated, real-world influence of varied SDoH and their quantifiable impact on thyroid cancer disparities across the United States. Methods: In a retrospective cohort study, 199,340 adult thyroid cancer patients from 1975 to 2017 were assessed for significant regression trends in months of follow-up/surveillance, survival, late staging, and treatment receipt across thyroid cancer-subtypes with increasing overall social vulnerability, as well as in 15 SDoH variables regarding socioeconomic status, minority-language status, household composition, and housing-transportation across all the U.S. counties while accounting for sociodemographic regional differences. Results: With increasing overall social vulnerability, decreases in months of follow-up were observed with patients with papillary, follicular, medullary, oncocytic, and anaplastic thyroid cancer (p = 0.001). Comparing lowest with highest vulnerability cohorts, relative decreases in months of surveillance ranged from 55.6% (14.5-6.5 months) with anaplastic to 17% (108.6-90.2) with oncocytic. Socioeconomic status vulnerabilities, followed by vulnerabilities in household composition and housing-transportation type, contributed to these overall trends. Similar survival decreases occurred across all thyroid cancer patients, ranging from 55.9% (9.6-4.2) with anaplastic to 28.3% (97-69.5) with oncocytic. Minority-language status vulnerabilities and housing-transportation types largely contributed to these trends. Increasing overall vulnerability was associated with increased odds of advanced staging for papillary (odds ratio [OR] = 1.07 [confidence interval, CI 1.03-1.12]) and decreased odds of indicated treatment via surgery (lowest, medullary: 0.91 [CI 0.84-0.99]), radiation therapy (lowest, anaplastic: 0.88 [CI 0.82-0.93]), and chemotherapy (lowest, oncocytic: 0.81 [CI 0.67-0.98]) were observed. Vulnerabilities in minority-language status and housing-transportation, followed by socioeconomic status vulnerabilities, were differential contributors to these overall vulnerability trends. Conclusions: Our results show significant detriments in thyroid cancer care and prognosis in the United States with increasing overall social vulnerability while identifying which SDoH quantifiably contribute more to disparities in inter-relational, real-world-like contexts.

Racial and ethnic and socioeconomic disparities in childhood cancer incidence trends in the United States, 2000-2019

BACKGROUND

Population-based surveillance of pediatric cancer incidence trends is critical to determine high-risk populations, drive hypothesis generation, and uncover etiologic heterogeneity. We provide a comprehensive update to the current understanding of pediatric cancer incidence trends by sex, race and ethnicity, and socioeconomic status (SES).

METHODS

The Surveillance, Epidemiology, and End Results 22 data (2000-2019) was used to summarize age-adjusted incidence rates for children and adolescents aged 0-19 years at diagnosis. The annual percentage change (APC) and 95% confidence interval (CI) were estimated to evaluate incidence trends by sex, race and ethnicity, and SES overall and for cancer subtypes. Tests of statistical significance were 2-sided.

RESULTS

Substantial variation was observed overall and for several histologic types in race and ethnicity- and SES-specific rates. Overall, we observed a statistically significant increase in incidence rates (APC = 0.8%, 95% CI = 0.6% to 1.1%). All race and ethnic groups saw an increase in incidence rates, with the largest occurring among non-Hispanic American Indian and Alaska Native children and adolescents (APC = 1.7%, 95% CI = 0.5% to 2.8%) and the smallest increase occurring among non-Hispanic White children and adolescents (APC = 0.7%, 95% CI = 0.5% to 1.0%). The lowest SES quintiles saw statistically significant increasing trends, while the highest quintile remained relatively stable (quintile 1 [Q1] APC = 1.6%, 95% CI = 0.6% to 2.6%; quintile 5 [Q5] APC = 0.3%, 95% CI = -0.1% to 0.7%).

CONCLUSIONS

Childhood cancer incidence is increasing overall and among every race and ethnic group. Variation by race and ethnicity and SES may enable hypothesis generation on drivers of disparities observed.

Prevalence and Trends of Thyroid Disease Among Adults, 1999-2018

BACKGROUND

Thyroid disease is a prominent endocrine disorder, yet the clinical epidemiology of this condition remains unclear. This study aims to describe the recent trends in the prevalence of thyroid disease in US adults from 1999-2018.

METHODS

This cross-sectional study used nationally representative data collected through the National Health and Nutrition Examination Survey (NHANES) from January 1, 1999 to December 31, 2018. Patients with thyroid disease were defined as patients who reported having a thyroid disease and were on thyroid-related treatment. Age-standardized prevalence of thyroid disease was calculated within 4-year survey periods (1999-2002, 2003-2006, 2007-2010, 2011-2014, and 2015-2018).

RESULTS

During the NHANES 1999-2018, a total of 57 540 participants were examined. The age-standardized prevalence of thyroid disease was 5.05% (95% CI, 4.55%-5.60%) from 2015-2018, signifying a significant increase from the 1999-2002 period (P <.0002). However, prevalent thyroid disease remained steady between 2003 and 2014. The highest prevalence of thyroid disease was observed in non-Hispanic Whites (8.1%; 95% CI, 7.3%-9.0%), individuals aged ≥60 years (15.4%; 95% CI, 13.3%-17.8%), and tended to be higher in women (7.6%; 95% CI, 6.8%-8.5%). Multiple regression analysis revealed that age, women sex, non-Hispanic White and Mexican American, body mass index, higher education and incomes were independently associated with increased risks of thyroid disease.

CONCLUSION

The age-standardized prevalence of thyroid disease among US adults increased from 1999-2003, remained stable between 2003 and 2014, and then saw an increase from 2014-2018, with the highest rate observed among elders, women, and non-Hispanic Whites.

Proportion of papillary thyroid microcarcinoma in Kerala, India, over a decade: a retrospective cohort study

Background

Overdiagnosis is a phenomenon where an indolent cancer is diagnosed that otherwise would not have caused harm to the patient during their lifetime. The rising incidence of papillary thyroid cancer (PTC) in various regions of the world is attributed to overdiagnosis. In such regions, the rates of papillary thyroid microcarcinoma (PTMC) are also rising. We aimed to study whether a similar pattern of rising PTMC is found in Kerala, a state in India, where there has been a doubling of thyroid cancer incidence over a decade.

Methods

We conducted a retrospective cohort study in two large government medical colleges, which are tertiary referral facilities in the state of Kerala. We collected data on the PTC diagnosis in Kozhikode and Thrissur Government Medical colleges from 2010 to 2020. We analysed our data by age, gender and tumor size.

Results

The incidence of PTC at Kozhikode and Thrissur Government Medical colleges nearly doubled from 2010 to 2020. The overall proportion of PTMC in these specimens was 18.9%. The proportion of PTMC only marginally increased from 14.7 to 17.9 during the period. Of the total incidence of microcarcinomas, 64% were reported in individuals less than 45 years of age.

Conclusion

The rise in the number of PTCs diagnosed in the government-run public healthcare centres in Kerala state in India is unlikely to be due to overdiagnosis since there was no disproportionate rise in rates of PTMCs. The patients that these hospitals cater to may be less likely to show healthcare-seeking behavior or ease of healthcare access which is closely associated with the problem of overdiagnosis.

Socioeconomic disparity in the association between fine particulate matter exposure and papillary thyroid cancer

BACKGROUND

Limited data exists suggesting that cumulative exposure to air pollution in the form of fine particulate matter (aerodynamic diameter ≤ 2.5 μm [PM2.5]) may be associated with papillary thyroid carcinoma (PTC), although this relationship has not been widely established. This study aims to evaluate the association between PM2.5 and PTC and determine the subgroups of patients who are at the highest risk of PTC diagnosis.

METHODS

Under IRB approval, we conducted a case-control study of adult patients (age ≥ 18) newly diagnosed with PTC between 1/2013-12/2016 across a single health care system were identified using electronic medical records. These patients were compared to a control group of patients without any evidence of thyroid disease. Cumulative PM2.5 exposure was calculated for each patient using a deep learning neural networks model, which incorporated meteorological and satellite-based measurements at the patients' residential zip code. Adjusted multivariate logistic regression was used to quantify the association between cumulative PM2.5 exposure and PTC diagnosis. We tested whether this association differed by gender, race, BMI, smoking history, current alcohol use, and median household income.

RESULTS

A cohort of 1990 patients with PTC and a control group of 6919 patients without thyroid disease were identified. Compared to the control group, patients with PTC were more likely to be older (51.2 vs. 48.8 years), female (75.5% vs 46.8%), White (75.2% vs. 61.6%), and never smokers (71.1% vs. 58.4%) (p < 0.001). After adjusting for age, sex, race, BMI, current alcohol use, median household income, current smoking status, hypertension, diabetes, COPD, and asthma, 3-year cumulative PM2.5 exposure was associated with a 1.41-fold increased odds of PTC diagnosis (95%CI: 1.23-1.62). This association varied by median household income (p-interaction =0.03). Compared to those with a median annual household income <$50,000, patients with a median annual household income between $50,000 and < $100,000 had a 43% increased risk of PTC diagnosis (aOR = 1.43, 95%CI: 1.19-1.72), and patients with median household income ≥$100,000 had a 77% increased risk of PTC diagnosis (aOR = 1.77, 95%CI: 1.37-2.29).

CONCLUSIONS

Cumulative exposure to PM2.5 over 3 years was significantly associated with the diagnosis of PTC. This association was most pronounced in those with a high median household income, suggesting a difference in access to care among socioeconomic groups.

National, sub-national, and risk-attributed burden of thyroid cancer in Iran from 1990 to 2019

An updated exploration of the burden of thyroid cancer across a country is always required for making correct decisions. The objective of this study is to present the thyroid cancer burden and attributed burden to the high Body Mass Index (BMI) in Iran at national and sub-national levels from 1990 to 2019. The data was obtained from the GBD 2019 study estimates. To explain the pattern of changes in incidence from 1990 to 2019, decomposition analysis was conducted. Besides, the attribution of high BMI in the thyroid cancer DALYs and deaths were obtained. The age-standardized incidence rate of thyroid cancer was 1.57 (95% UI: 1.33-1.86) in 1990 and increased 131% (53-191) until 2019. The age-standardized prevalence rate of thyroid cancer was 30.19 (18.75-34.55) in 2019 which increased 164% (77-246) from 11.44 (9.38-13.85) in 1990. In 2019, the death rate, and Disability-adjusted life years of thyroid cancer was 0.49 (0.36-0.53), and 13.16 (8.93-14.62), respectively. These numbers also increased since 1990. The DALYs and deaths attributable to high BMI was 1.91 (0.95-3.11) and 0.07 (0.04-0.11), respectively. The thyroid cancer burden and high BMI attributed burden has increased from 1990 to 2019 in Iran. This study and similar studies' results can be used for accurate resource allocation for efficient management and all potential risks' modification for thyroid cancer with a cost-conscious view.

Temporal Trends in Papillary and Follicular Thyroid Cancer Incidence from 1995 to 2019 in Adults in Denmark According to Education and Income

Background: Thyroid cancer incidence has increased over the past decades. Differences in incidence trends have been observed depending on socioeconomic status. Here, we describe trends in the incidence of papillary thyroid cancer (PTC) and follicular thyroid cancer (FTC) in Denmark by level of education and income. Methods: All PTC and FTC cases registered in the Danish Cancer Registry from 1995 to 2019 were identified. Individual-level information on education and income was obtained from nationwide registries. We calculated age-standardized incidence rates according to sex, tumor size, education and income, and estimated incidence trends by average annual percentage change (AAPC) and corresponding confidence intervals [CIs] for the periods 1995 to 2004 and 2005 to 2019 by using Poisson regression models. Results: We identified 3454 cases of PTC and 972 cases of FTC. From 2005 to 2019 among women, the incidence of PTC increased across all levels of education (AAPC_{short education} = 12.5% [CI 9.8 to 15.3]; AAPC_{medium education} = 8.1% [CI 6.4 to 9.9]; AAPC_{long education} = 7.3% [CI 5.4 to 9.2]). The same pattern was seen for income. The incidence of FTC increased in all levels of education (AAPC_{short education} = 10.5% [CI 5.8 to 15.4]; AAPC_{medium education} = 4.0% [CI 0.9 to 7.3]; AAPC_{long education} = 4.3% [CI 0.6 to 8.1]), with the same pattern for income. Similar trends were observed among men, in both small (≤2 cm) and large (>2 cm) PTCs and from 1995 to 2004 in both sexes. Conclusions: Enhanced detection of thyroid cancer among all levels of education and income cannot be ruled out, and in addition, our results may suggest a true increase in the incidence of differentiated thyroid cancer.

Impact of healthcare services on thyroid cancer incidence among World Trade Center-exposed rescue and recovery workers

BACKGROUND

A recent study of World Trade Center (WTC)-exposed firefighters and emergency medical service workers demonstrated that elevated thyroid cancer incidence may be attributable to frequent medical testing, resulting in the identification of asymptomatic tumors. We expand on that study by comparing the incidence of thyroid cancer among three groups: WTC-exposed rescue/recovery workers enrolled in a New York State (NYS) WTC-medical monitoring and treatment program (MMTP); WTC-exposed rescue/recovery workers not enrolled in an MMTP (non-MMTP); and the NYS population.

METHODS

Person-time began on 9/12/2001 or at enrollment in a WTC cohort and ended at death or on 12/31/2015. Cancer data were obtained through linkages with 13 state cancer registries. We used Poisson regression to estimate rate ratios (RRs) and 95% confidence intervals (CIs) for MMTP and non-MMTP participants. NYS rates were used as the reference. To estimate potential changes over time in WTC-associated risk, change points in RRs were estimated using profile likelihood.

RESULTS

The thyroid cancer incidence rate among MMTP participants was more than twice that of NYS population rates (RR = 2.31; 95% CI = 2.00-2.68). Non-MMTP participants had a risk similar to NYS (RR = 0.96; 95% CI = 0.72-1.28). We observed no change points in the follow-up period.

CONCLUSION

Our findings support the hypothesis that no-cost screening (a benefit provided by WTC-MMTPs) is associated with elevated identification of thyroid cancer. Given the high survival rate for thyroid cancer, it is important to weigh the costs and benefits of treatment, as many of these cancers were asymptomatic and may have been detected incidentally.

Global burden of thyroid cancer and its attributable risk factors in 204 countries and territories from 1990 to 2019

Background

To investigate the burden of thyroid cancer and its attributable risk factors in 204 countries and territories during 30 years.

Methods

We extracted data from the Global Burden of Disease (GBD) 2019 database, including incidence, mortality, disability‐adjusted life‐years (DALYs), and the attributable risk factors of thyroid cancer from 1990 to 2019. Estimated annual percentage changes (EAPC) were calculated to assess the changes in age‐standardized incidence rate (ASIR), age‐standardized mortality rate (ASMR), and age‐standardized DALYs rate (ASDR). We also examined the associations between cancer burden and the sociodemographic index (SDI).

Results

The global new cases, death, and DALYs of thyroid cancer in 2019 were 233 847 (95% UI: 211 637–252 807), 45 576 (95% UI: 41 290‐48 775), and 1 231 841 (95% UI: 1 113 585–1 327 064), respectively. From 1990 to 2019, the ASIR of thyroid cancer showed an upward trend (EAPC = 1.25), but ASMR (EAPC = −0.15) and ASDR (EAPC = −0.14) decreased. The burden of thyroid cancer varied at regional and national levels, but the association between ASIR and SDI was positive. We found that the burden of thyroid cancer was mainly concentrated in females and that the age of onset tended to be younger. The proportion of DALYs from thyroid cancer attributable to high body‐mass index was higher in high SDI regions, especially in males.

Conclusions

The global incidence of thyroid cancer has continued to increase in the past three decades. The high body‐mass index as an important risk factor for thyroid cancer deserves greater attention, especially in high SDI regions.

Effects of Social Determinants of Health Care on Pediatric Thyroid Cancer Outcomes in the United States

OBJECTIVE

To identify social determinants of health care that are associated with poorer pediatric well-differentiated thyroid cancer (WDTC) outcomes and increased stage at presentation.

STUDY DESIGN

Using the SEER database (Surveillance, Epidemiology, and End Results), we retrospectively gathered data on pediatric WDTC across the United States between 1973 and 2015.

SETTING

All patients between 0 and 19 years old with a diagnosis of WDTC were included.

METHODS

Patient variables were analyzed for relationships to AJCC stage at presentation (American Joint Committee on Cancer), overall survival, and disease-specific survival.

RESULTS

Among 3913 patients with pediatric thyroid cancer, 3185 were female (81.4%), 3366 had papillary thyroid cancer (85.3%), and 367 had follicular thyroid cancer (9.4%). Two- and 5-year overall and disease-specific survival approached 100%. However, when outcomes were analyzed by specific populations, male sex, non-Caucasian race, poverty, and language isolation were linked to worse overall survival. Male sex and poverty were associated with poorer disease-specific survival. Regarding overall AJCC stage at presentation, male sex and Black race were related to higher overall presenting AJCC stage. Later AJCC T stage at presentation was seen in male, Hispanic, Asian, and Black patients. There were no variables significantly related to following through with recommended surgery.

CONCLUSION

Pediatric WDTC continues to carry an excellent prognosis in the United States. However, when we consider specific populations, the social determinants of health care affect survival and disease burden at presentation: male sex, poverty, language isolation, and race affected survival and/or AJCC stage at presentation in pediatric WDTC.

Spatial clustering and meso-scale correlates of thyroid disorder among women in India: evidence from the National Family Health Survey (2015–16)

Purpose

Thyroid disorders are a major public health burden. Generally, women exhibit higher differentials in the prevalence of these disorders. This study focuses on the socio-economic and behavioural correlates of thyroid disorders along with their spatial clustering among women of reproductive age in India.

Methods

The study uses dataset from the fourth National Family Health Survey (NFHS-4) carried out in 2015–16 to assess self-reported thyroid disorders. Poor–rich ratio (PRR) and concentration index (CI) were used to study the variation in thyroid disorder among women arising out of economic inequality. Moran’s I statistics and bivariate local spatial autocorrelation (BiLISA) maps were used to understand spatial dependence and clustering of thyroid disorder. Spatial lag and error models were applied to examine the correlates of the disorder.

Results

Thyroid disorder prevalence was higher among women from socio-economically better-off households. Adjusted effects showed that users of iodized salt were 1.14 times more likely to suffer from a thyroid disorder as compared to non-users, which is contrary to the general belief that a higher percentage of consumption of iodide salt leads to a lower prevalence of thyroid disorder. A higher autoregressive coefficient (0.71) indicated significantly higher spatial clustering in thyroid disorders.

Conclusions

The prevalence of thyroid disorder in India depends appreciably on spatial and various ecological factors. Sedentary lifestyles among women may be aggravating diseases, which has strong linkage with thyroid disorders. It is strongly recommended to effectively integrate universal salt iodization with activities geared towards the elimination of iodine deficiency disorders.

Neck CT imaging and correlation with thyroid cancer incidence across age, gender and race

OBJECTIVE

Incidental detection of thyroid cancers has been proposed as a cause of thyroid cancer increases over past decades, but few studies assess the impact of imaging utilization on thyroid cancer incidence. This study quantifies neck CT prevalence and its relationship with thyroid cancer incidence as a function of age, sex and race.

DESIGN AND PATIENTS

Medical records of over 1 million patients at our institution were retrospectively analysed to quantify neck CT prevalence from 2004 to 2011 (study period). A national cancer database was used to compute thyroid cancer incidences over the study period and a reference period (1974-81) and to calculate change in thyroid incidence between the two periods. Both populations were partitioned into demographic subgroups of varying age, sex and race. Linear correlation between neck imaging and thyroid cancer incidence changes among subgroups was assessed using Pearson's correlation.

RESULTS

Neck CT imaging and change in thyroid cancer incidence varied across all examined demographic variables, particularly age. When stratifying by age, CT use correlated strongly with recent national thyroid cancer incidence (R = .97) and with 30-year change in thyroid cancer incidence (R = .87). Across all demographic subgroups, CT prevalence correlated strongly and positively with change in thyroid cancer incidence (R = .60), greater for whites (R = .60) and blacks (R = .70) than other races (R = .28).

CONCLUSION

Differences in neck CT usage strongly and positively correlates with the variation in thyroid cancer trends based on age, gender and race.

SQSTM1/p62 Promotes Cell Growth and Triggers Autophagy in Papillary Thyroid Cancer by Regulating the AKT/AMPK/mTOR Signaling Pathway

Background

Thyroid cancer is one of the most common endocrine malignancies worldwide, and papillary thyroid cancer (PTC) is the most common pathologic type of thyroid cancer. SQSTM1/p62 activity mediates different biological functions. This study aimed to investigate the effect of SQSTM1/p62, a multifunctional receptor, on biological function and autophagy characteristics in the human PTC cell line TPC-1.

Methods

A total of 105 primary PTC samples and matched adjacent normal thyroid tissue samples were obtained to evaluate the expression of p62 in clinical patients. A similar p62 expression pattern was found in PTC cell lines and normal human thyroid follicular epithelial cells. To evaluate the effect of SQSTM1/p62 on TPC-1 cells, we constructed the p62 knockout cell line p62-KO-TPC-1. Cell proliferation, cell cycle, and cell apoptosis were analyzed by colony formation tests, Cell Counting Kit-8 (CCK-8) assays and flow cytometry in vitro. TPC-1 and p62-KO-TPC-1 human PTC cell lines in the logarithmic growth phase were subcutaneously implanted into BALB/c nude mice to verify their proliferation effect in vivo. Furthermore, western blotting and immunohistochemistry (IHC) were used to detect the expression of AKT/AMPK/mTOR signaling pathway-related proteins.

Results

Overall, p62 expression was higher in tumor tissues than in normal tissues in 73 of 105 PTC patients (69.5%). The expression level of p62 in the PTC cell line was higher than that in the normal thyroid cell line. Our data indicated that in vitro, p62 deficiency could decrease the number of colonies, inhibit cell growth and the cell cycle, and induce apoptosis. Tumor xenograft experiments in BALB/c nude mice corroborated these findings. Moreover, the molecular mechanism was explored by western blotting, and we found that the AMPK/AKT/mTOR pathway was involved.

Conclusions

The results indicate that p62 might mediate cell autophagy and apoptosis in TPC-1 cells via the AMPK/AKT/mTOR pathway and could be used as a potential therapeutic approach for PTC.

Trend dynamics of thyroid cancer incidence among China and the U.S. adult population from 1990 to 2017: a joinpoint and age-period-cohort analysis

BACKGROUND

Thyroid cancer (TC) is the most common malignant disease of the endocrine system. Based on the previously published reports, the incidence of TC has been increasing in the past 25 years, and the reason for the increase is not yet clear. The present study aims to reveal the long-term trends and age-period-cohort effects for the incidence of TC in China and the U.S. from 1990 to 2017.

METHODS

We examined the trends of TC incidence and the average annual percentage change (AAPC) of rate using the Joinpoint regression analysis in the two countries, for the different genders (men/women) in the Global Burden of Disease (GBD 2017). We further used an age-period-cohort model to analyze age-period-cohort effects on TC incidence.

RESULTS

The ASIR of China increased markedly with AAPC of 4.5% (95% confidence interval (CI): 4.0, 5.0%) and 1.8% (1.6, 2.0%) for men and women during 1990-2017. The ASIR of the U. S increased by 1.4% (1.0, 1.8%) and 1.3% (0.9, 1.7%) for men and women from 1990 to 2017.TC increased with the age and period. Aging was one of the most influential factors of TC in China. The age effect increased markedly in the U.S. compared with China. The period effect showed an increase in China while that tended to grow steadily during 1990-2017 in the U.S. The cohort effect peaked in 1963-1967 birth cohorts for men and women in China and declined consistently in the birth cohort in the U.S.

CONCLUSION

From 1990 to 2017, due to ionizing radiation and over-diagnosis, age-standardized TC incidence rates in both genders rose in China and the U.S. The standardized incidence rate of women is higher than that of men. It is necessary to provide women with reasonable prevention and protection measures for TC. We need to apply for health services and screening to reduce ionizing radiation.

Radioactive iodine therapy may not improve disease-specific survival in follicular variant papillary thyroid cancer without distant metastasis: A propensity score-matched analysis

BACKGROUND

Whether radioactive iodine (RAI) therapy is effective in improving disease-specific survival (DSS) in patients with follicular variant papillary thyroid cancer (FVPTC) without distant metastasis remains unclear.

METHODS

Patients with FVPTC were identified from the Surveillance, Epidemiology, and End Results (SEER) database between 2004 and 2015. The Kaplan-Meier method and the Cox proportional hazards regression model were used to evaluate DSS. Propensity score-matched analysis was performed to reduce the influence of confounding bias.

RESULTS

RAI did not improve DSS, even in patients with aggressive features such as T4 classification (p = 0.658), extrathyroidal extension (p = 0.083), lateral lymph node metastasis (p = 0.544), and ≥5 metastatic lymph nodes (p = 0.599).

CONCLUSION

RAI did not affect DSS in patients with FVPTC without distant metastases in this SEER database study. Multicenter, prospective studies including recurrence and molecular information should be conducted to comprehensively evaluate the effects of RAI on FVPTC.

Screening and the epidemic of thyroid cancer in China: An analysis of national representative inpatient and commercial insurance databases

Reasons behind the rapid increase of thyroid cancer (TC) in China are uncertain. We assessed the burden of TC and the role of access to screening and salt iodization. We analyzed two national databases in China: Hospital Quality Monitoring System (HQMS) and China Reinsurance Company (CRC) database. HQMS covered 1037 (44.3%) Class 3 hospitals and 76 263 617 Class 3 hospital inpatients in 2013 to 2017 and CRC covered 93 123 018 clients in 2000 to 2016. The proportion of TC inpatients among inpatients in HQMS and TC incidence in critical illness insurance buyers were used to evaluate the association with screening and iodine status. Between 2013 and 2017, the proportion of TC patients in HQMS with urban employee medical insurance and good access to screening increased sharply while there was little change among those with the other two forms of medical insurance. Across provinces, the proportion of TC inpatients in HQMS was positively correlated with per capita disposable income but not with median urinary iodine. Similar findings were observed in the CRC database. In 2017, approximately 1000 individuals were overdiagnosed with TC daily. We conservatively forecast that 5.1 million healthy individuals would become TC patients unnecessarily between 2019 and 2030. Our findings suggested the epidemic of TC in China was substantially underestimated. It was associated with screening but not with salt iodization.

What's new?

In recent decades, the incidence of thyroid cancer has increased rapidly worldwide. In China, the role of thyroid cancer screening as part of regular health checks and potential overdiagnosis remain unclear. Moreover, there are concerns among the general public that mandatory salt iodization may have contributed to the epidemic of thyroid cancer. Here, the authors found that the increase in thyroid cancer in China is associated with increased access to health care and screening, but not with salt iodization. Moreover, the results suggest that approximately 1000 individuals are overdiagnosed with thyroid cancer daily, calling for urgent measures to prevent overdiagnosis.

Evaluation of Medical Surveillance and Incidence of Post-September 11, 2001, Thyroid Cancer in World Trade Center-Exposed Firefighters and Emergency Medical Service Workers

IMPORTANCE

Elevated incidence rates of thyroid cancer among World Trade Center (WTC)-exposed individuals may be associated with the identification of asymptomatic cancers during medical surveillance.

OBJECTIVE

To examine the association between WTC exposure and thyroid cancer among Fire Department of the City of New York (hereafter, Fire Department) rescue/recovery workers as well as the association with medical surveillance.

DESIGN, SETTING, AND PARTICIPANTS

This closed-cohort study classified the method of detection (asymptomatic and symptomatic) of thyroid cancers in 14 987 men monitored through the Fire Department-WTC Health Program diagnosed from September 12, 2001, to December 31, 2018. Age-, sex-, and histologic-specific Fire Department incidence rates were calculated and compared with demographically similar men in Olmsted County, Minnesota, from the Rochester Epidemiology Project using age-standardized rates, relative rates (RRs), and 95% CIs. The secondary analysis was restricted to papillary carcinomas.

EXPOSURES

World Trade Center exposure was defined as rescue/recovery work at the WTC site from September 11, 2001, to July 25, 2002.

MAIN OUTCOMES AND MEASURES

The outcomes evaluated comprised (1) number of incident thyroid cancers and their detection method categorizations in the Fire Department and Rochester Epidemiology Project cohorts; (2) Fire Department, Rochester Epidemiology Project, and Surveillance, Epidemiology, and End Results-21 age-standardized incidence rates of thyroid cancer; and (3) RRs comparing Fire Department and Rochester Epidemiology Project overall and by detection method categorization.

RESULTS

Seventy-two post-9/11 Fire Department cases of thyroid cancer were identified. Among the 65 cases (90.3%) with a categorized detection method, 53 cases (81.5%) were asymptomatic and 12 cases (18.5%) were symptomatic. Median (interquartile range) age at diagnosis was 50.2 (44.0-58.6) vs 46.6 (43.9-52.9) years for asymptomatic vs symptomatic cases. Associated primarily with asymptomatic cancers, the overall age-standardized incidence of Fire Department thyroid cancers (24.7; 95% CI, 17.4-52.3) was significantly higher than the Rochester Epidemiology Project (10.4; 95% CI, 8.5-12.7) and Surveillance, Epidemiology, and End Results-21 (9.1; 95% CI, 9.0-9.1) per 100 000 person-years. Furthermore, the RR of thyroid cancer among symptomatic men in Fire Department cases was not significantly different from that of men in the Rochester Epidemiology Project (0.8; 95% CI, 0.4-1.5); however, the rate of asymptomatic cancers was more than 3-fold that of the Rochester Epidemiology Project rate (RR, 3.1; 95% CI, 2.1-4.7).

CONCLUSIONS AND RELEVANCE

Excess asymptomatic thyroid cancer in Fire Department WTC-exposed rescue/recovery workers is apparently attributable to the identification of occult lesions during medical surveillance. Among WTC-exposed cohorts and the general population, these findings appear to have important implications for how thyroid cancer incidence rates are interpreted and how diagnoses should be managed.

Epidemiologic, Clinical, Ultrasonographic, and Cytological Features of Thyroid Nodules in Predicting Malignancy Risk: A Retrospective Study of 442 French Afro-Caribbean Patients

OBJECTIVE

To evaluate epidemiologic, clinical, cytological, and ultrasonographic features of thyroid nodules in a sample French Afro-Caribbean population to determine if the standard criteria for predicting malignancy risk are applicable to this specific ethnic population. Methods and Design. This retrospectively designed study consisted of 442 patients who had consulted with the Endocrinology Department in Martinique (French overseas department) between 2007 and 2011. Of the 442 patients, 641 ultrasound-guided fine-needle aspirations (US-FNA) were performed by two experienced endocrinologists, and 212 patients underwent surgery. The geographical situation, age, gender of the patient, clinical and ultrasonographic features, TSH level, and US-FNA results were considered and cross-referenced with their pathology results.

RESULTS

The overall malignancy rate on final histopathology was 9% (women only), 80% of which were papillary cancer, and 20% were follicular cancer. Occult micropapillary carcinoma represented 35% of the papillary cancer. There was no significant difference in age, nodule localization, number of nodules, or thyroid function test between benign and malignant nodules. Contrary to the literature, we found only 12% incidentaloma in our series, while more than half of the nodules were discovered on palpation or as a clinical symptom. Hypoechogenicity in solid pattern nodules and nodules between 2 and 3 cm in size revealed a high diagnostic value in detecting malignancy. The corresponding rate of malignancy on Bethesda system histopathologic examination was as follows: 0% in undiagnosed (I), 0% benign (II) (micropapillary), 5% (FLUS)/atypia (III), 9% follicular neoplasm (IV), 33% suspected malignancy (V), and no malignant cytology (VI). These results show a different Bethesda system predictive value for this French Afro-Caribbean population.

CONCLUSION

Studies evaluating ethnic cancer disparities among patients with thyroid cancer are limited and do not specifically focus on the French Afro-Caribbean population. Despite rare thyroid incidentaloma, 35% of the papillary cancer cases were micropapillary carcinoma, and the incidence and standardized mortality rate in Martinique are lower than in metropolitan France. The malignant risk distribution of thyroid FNA Bethesda classification in this sample population differs from the standard risk, and it is necessary to take that into account in the decision to operate by associating it with echographic malignancy criteria.

Incidence of thyroid cancer in Puerto Rico and the US by racial/ethnic group, 2011-2015

BACKGROUND

Puerto Rico has the highest incidence rate of thyroid cancer (TC) in the Americas and the third highest rate worldwide. The purpose of this study was to compare the burden of TC between the population of PR and United States (US) non-Hispanic Whites (NHW), non-Hispanic Blacks (NHB), and US Hispanics (USH) during the period 2011-2015.

METHODS

TC data for the period 2011-2015 was obtained from the Puerto Rico Central Cancer Registry (PRCCR) and the Surveillance Epidemiology and Ends Results Program (SEER) 18 Registries Research Data. TC was categorized in: papillary carcinoma (PTC), and other TC histologic types. Data was analyzed by sex, age groups, and histologic type. Racial/ethnic differences by sex, age, and histologic types were assessed using the Standardized Rate Ratio (SRR) and its 95% CI.

RESULTS

During the period 2011-2015 there were 5175 and 65,528 cases of TC diagnosed in PR and the US, respectively. The overall age-adjusted incidence rate of PTC was almost two-fold higher in PR than in the US (25.8/100,000 vs. 12.9/100,000). Among PR women, the incidence rate of PTC was 40.0/100,000 compared to 19.4/100,000 in US. PR women had 83% increased risk of being diagnosed with PTC than NHW women, a 2.25-fold increased risk than USH, and 3.45-fold increased risk than NHB women. For men, PR had 34% increased risk of being diagnosed with PTC than NHW men, 2.2-fold increased risk than USH men, and 3.2-fold higher risk than in NHB men.

CONCLUSION

Further research is needed to understand this disparity in the island. This research should address the extent of overdiagnosis in PR, the role of health insurance status and insurance type, characteristics of the healthcare delivery system as well as the role of patient and environmental factors.

Thyroid Cancer in Ecuador, a 16 years population-based analysis (2001-2016)

BACKGROUND

Thyroid cancer is the most frequent endocrine neoplasia worldwide. Information from Andean countries is scarce. In Ecuador there is no reports available of the epidemiology of this type of cancer. The aim of this study is to present the epidemiology and the burden of disease of thyroid cancer.

METHODS

This is a cross-sectional population-based analysis of thyroid cancer epidemiology in Ecuador from 2001 to 2016. The variables studied were the overall mortality rate, socio-demographics characteristics of the hospitalized patients, geographical trends and the burden of thyroid cancer in Ecuador. All the data was obtained from the official records reported by the Ministry of Public Health's and retrieved from the public databases of the Vital Statistics Deaths and Births Databases and the National Institute of Census and Statistics (INEC).

RESULTS

In Ecuador, over a period of 16 years from 2001 to 2016 a total of 23,632 hospital admissions were reported, which caused 1539 deaths due thyroid cancer. Data demonstrated an annual mean of 1477 cases, which caused 96 deaths per year in average. The annual incidence fluctuated from 3 in 2001 to 22 in 2016 per 100,000 inhabitants. Women were 5 times more likely than men to have thyroid cancer. The average length of stay for both sexes were 4 days. The mortality attributable to thyroid cancer represent less than 0.3% of all cancer deaths.

CONCLUSION

Ecuador has one of the highest rates of thyroid cancer in Latin America, ranking first among women in Latin America. Although this cancer is frequent, mortality rate is relatively low. As this is the first national report of thyroid cancer in the country, a further analysis of the pathological variants and the grading of this neoplasia is needed.

The Relationship Between Human Development Index and Its Components with Thyroid Cancer Incidence and Mortality: Using the Decomposition Approach

BACKGROUND

The link between age specific-rates of thyroid cancer (TC) and human development index (HDI) and also its components can be a new direction for planning by policy makers.

OBJECTIVES

This study aimed at identifying the relationship between TC rates by gender, and HDI and its components in different regions of the world.

METHODS

An ecological study was conducted; the data was obtained from the GLOBOCAN project in 2012. Inequality in TC estimates (age-specific incidence and mortality rates), according to the HDI and its components was calculated. Concentration index (CI) was used to estimate inequality and CI was decomposed to determine contribution of HDI and its components in inequality.

RESULTS

The inequality index (CI) was 0.29 (95% CI: 0.21 - 0.38) and -0.15 (95% CI: -0.23 - 0.06) for incidence and mortality of TC by HDI, respectively. The important contributors in inequality for incidence rates of TC were life expectancy at birth (0.30), mean years of schooling (0.26), and expected years of schooling (0.18). The important contributors in inequality of mortality rates were mean years of schooling (0.19), expected years of schooling (0.17), and urbanization (0.17).

CONCLUSIONS

According to the findings of this study, global inequalities exist in the TC incidence and mortality rates; incidence rates of TC are more concentrated in countries with high HDI, yet inequality index showed that deaths occurred more in disadvantaged countries.

INCIDENTAL THYROID NODULES: RACE/ETHNICITY DISPARITIES AND OUTCOMES

OBJECTIVE

Black patients have a significantly lower incidence of well-differentiated thyroid cancer (WDTC) compared to all other race/ethnic groups, while white patients appear to be at greater risk. This study examines incidental thyroid nodules (ITNs) to assess whether racial disparities in WDTC arise from a differential discovery of ITNs-perhaps due to socioeconomic disparities-or reflect true differences in thyroid cancer rates.

METHODS

A retrospective review was performed of all patients who underwent fine-needle aspiration (FNA) of thyroid nodules by our academic medical center's endocrinology division between January 2006 and December 2010. Medical records were reviewed to identify whether the biopsied thyroid nodule was discovered incidentally through nonthyroid-related imaging or identified by palpation.

RESULTS

FNAs were performed on 1,369 total thyroid nodules in 1,141 study patients; 547 (48%) were classified as white, and 593 (52%) were classified as nonwhite. Among this cohort, 36.6% of patients underwent biopsy for an ITN. White patients were 1.6 times more likely to have undergone a biopsy for a nodule that was incidentally identified compared to nonwhites ( P<.0001). Indicators of socioeconomic status (SES) did not have a significant association with ITNs. Within the ITN cohort, 4.9% of nonwhite patients were found to have a thyroid malignancy compared to 12.9% of white patients ( P<.01).

CONCLUSION

The higher incidence of thyroid cancer in white patients appears to be not only due to diagnostic bias, but also to a true difference in cancer prevalence.

ABBREVIATIONS

FNA = fine-needle aspiration; ITN = incidental thyroid nodule; SEER = Surveillance Epidemiology and End Results; SES = socioeconomic status; WDTC = well-differentiated thyroid cancer.

Evidence of a positive association between malpractice climate and thyroid cancer incidence in the United States

The incidence of thyroid cancer has risen dramatically in the past few decades. The cause of this is unclear, but several lines of evidence indicate it is largely due to overdiagnosis, the diagnosis of tumors that would have never manifest clinically if untreated. Practices leading to overdiagnosis may relate to defensive medicine. In this study, we evaluated the association between malpractice climate and incidence of thyroid, breast, prostate, colon, and lung cancer in U.S. states from 1999-2012 using publicly available government data. State-level malpractice risk was quantified as malpractice payout rate, the number of malpractice payouts per 100,000 people per state per year. Associations between state-level cancer incidence, malpractice payout rate, and several cancer risk factors were evaluated. Risk factors included several social determinants of health, including factors predicting healthcare access. States with higher malpractice payout rate had higher thyroid cancer incidence, on both univariate analysis (r = 0.51, P = 0.009, Spearman) and multivariate analysis (P<0.001, multilevel model). In contrast, state-level malpractice payout rate was not associated with incidence of any other cancer type. Malpractice climate may be a social determinant for being diagnosed with thyroid cancer. This may be a product of greater defensive medicine in states with higher malpractice risk, which leads to increased diagnostic testing of patients with thyroid nodules and potential overdiagnosis. Alternatively, malpractice risk may be a proxy for another, unmeasured risk factor.

Contribution of industrial density and socioeconomic status to the spatial distribution of thyroid cancer risk in Hangzhou, China

BACKGROUND

The thyroid cancer (TC) incidence in China has increased dramatically during the last three decades. Typical in this respect is the case of Hangzhou city (China), where 7147 new TC cases were diagnosed during the period 2008-2012. Hence, the assessment of the TC incidence risk increase due to environmental exposure is an important public health matter.

METHODS

Correlation analysis, Analysis of Variance (ANOVA) and Poisson regression were first used to evaluate the statistical association between TC and key risk factors (industrial density and socioeconomic status). Then, the Bayesian maximum entropy (BME) theory and the integrative disease predictability (IDP) criterion were combined to quantitatively assess both the overall and the spatially distributed strength of the "exposure-disease" association.

RESULTS

Overall, higher socioeconomic status was positively correlated with higher TC risk (Pearson correlation coefficient=0.687, P<0.01). Compared to people of low socioeconomic status, people of median and high socioeconomic status showed higher TC risk: the Relative Risk (RR) and associated 95% confidence interval (CI) were found to be, respectively, RR=2.29 with 95% CI=1.99 to 2.63, and RR=3.67 with 95% CI=3.22 to 4.19. The "industrial density-TC incidence" correlation, however, was non-significant. Spatially, the "socioeconomic status-TC" association measured by the corresponding IDP coefficient was significant throughout the study area: the mean IDP value was -0.12 and the spatial IDP values were consistently negative at the township level. It was found that stronger associations were distributed among residents mainly on a stripe of land from northeast to southwest (consisting mainly of sub-district areas). The "industrial density-TC" association measured by its IDP coefficient was spatially non-consistent.

CONCLUSIONS

Socioeconomic status is an important indicator of TC risk factor in Hangzhou (China) whose effect varies across space. Hence, socioeconomic status shows the highest TC risk effect in sub-district areas.

Standardized cancer incidence disparities in Upper Manhattan New York City neighborhoods: the role of race/ethnicity, socioeconomic status, and known risk factors

We examined the effects of race/ethnicity and neighborhood, a proxy of socioeconomic status, on cancer incidence in New York City neighborhoods: East Harlem (EH), Central Harlem (CH), and Upper East Side (UES). In this ecological study, Community Health Survey data (2002-2006) and New York State Cancer Registry incidence data (2007-2011) were stratified by sex, age, race/ethnicity, and neighborhood. Logistic regression models were fitted to each cancer incidence rate with race/ethnicity, neighborhood, and Community Health Survey-derived risk factors as predictor variables. Neighborhood was significantly associated with all cancers and 14 out of 25 major cancers. EH and CH residence conferred a higher risk of all cancers compared with UES (OR=1.34, 95% CI 1.07-1.68; and OR=1.39, 95% CI 1.12-1.72, respectively). The prevalence of diabetes and tobacco smoking were the largest contributors toward high cancer rates. Despite juxtaposition and similar proximity to medical centers, cancer incidence disparities persist among EH, CH, and UES neighborhoods. Targeted, neighborhood-specific outreach may aid in reducing cancer incidence rates.

Growing incidence of thyroid carcinoma in recent years: Factors underlying overdiagnosis

There is an increasing incidence of well-differentiated thyroid cancer worldwide. Much of the increase is secondary to increased detection of small, low-risk tumors, with questionable clinical significance. This review addresses the factors that contribute to the increasing incidence and considers environmental, and patient-based and clinician-led influences. Articles addressing the causes of the increased incidence were critically reviewed. A complex interplay of environmental, medical, and social pressures has resulted in increased awareness of the thyroid disease risk, increased screening of thyroid cancers, and increased diagnosis of thyroid cancers. Although there is evidence to suggest that the true disease incidence may be changing slightly, most of the increase is related to factors that promote early diagnosis of low-risk lesions, which is resulting in a significant phenomenon of overdiagnosis. An improved understanding of these pressures at a global level will enable healthcare policymakers to react appropriately to this challenge in the future.

Increased incidence of thyroid cancer in Navarra (Spain). Evolution and clinical characteristics, 1986-2010

INTRODUCTION

The latest published studies show an increased incidence of thyroid cancer worldwide. The aim of this study was to analyze the changes in the incidence of thyroid cancer in Navarra and its clinical presentation regarding sex, histological subtype and size over the last 25 years.

METHODS

Thyroid cancer incidence rates were calculated on the basis of data from the Cancer Registry of Navarra during 1986-2010. Clinical data were obtained from the historical cohort of the Hospital Registry of Cancer of Navarra, which includes all the new cases of differentiated thyroid carcinoma diagnosed and treated in the public health network of this Community in that period.

RESULTS

The overall incidence of thyroid cancer in Navarra increased over the last 25 years, with an increase in the adjusted rate in men from 2.24 (1986-1990) to 5.85 (2006-2010) per 100,000 population/year (P<.001) and in women from 9.05 to 14.04, respectively (P<.001). This increase occurs only in papillary carcinoma. The clinical characteristics of 739 patients with differentiated thyroid cancer were studied. The mean age at diagnosis increased over the years and the predominance of women (about 80%) remains stable. Mean tumor size decreased over the five-year periods from 30.9 to 22.5mm (P<.001), the proportion of microcarcinomas (T1a) increased from 8.8% to 30% (P<.001) and, despite this increase, there were no statistical differences in the TNM stage at diagnosis during the study period. The distribution of histological variants of papillary and follicular carcinoma did not change over 25 years.

CONCLUSIONS

During the period studied, the incidence of thyroid cancer increased in Navarra in both sexes. The increase occurred only in papillary carcinoma, without changes in the distribution of his histological variants. The increase in the proportion of T1a tumors is remarkable, but the TNM stage distribution was maintained. These results suggest an increase in the diagnosis of thyroid microcarcinomas due to changes in clinical practice, without ruling out a real increase in the incidence of papillary carcinoma in Navarra.

Rising Thyroid Cancer Incidence in Southern India: An Epidemic of Overdiagnosis?

BACKGROUND

Thyroid cancer incidence is rising in high-income countries. This increase in disease burden is attributed to the phenomenon of overdiagnosis.

OBJECTIVE

We aimed to investigate trends in thyroid cancer rates in India, focusing on the state of Kerala in southern India, which has reported a high incidence of the disease.

DESIGN

Population-based study using data from the National Cancer Registry Program.

PARTICIPANTS

We used data from the Population Based Cancer Registries for Thiruvananthapuram (capital of Kerala state), Delhi, Mumbai, Bangalore, and Chennai. We used data for three reporting periods from 2005 to 2014 (represented as 2006, 2009, and 2012).

MAIN OUTCOME MEASURES

We reported the age-adjusted incidence rate (AARi) and mortality rate (AARm) per 100,000 women and the proportion of thyroid cancers diagnosed in females per 100 cancer cases.

RESULTS

During 2006, the AARi for thyroid cancer in women in Thiruvananthapuram was 6.9 per 100,000, rising to 10 in 2009 and 13.3 in 2012. There was a 93% increase in incidence rates over less than a decade. The AARis in the other four cities were stable. In 2012, Thiruvananthapuram had at least a fourfold higher incidence compared with other regions. Thyroid was the primary site in one of every 10 cancers diagnosed in Thiruvananthapuram, and large numbers of patients were <40 years of age. The AARm remained stable in all regions.

CONCLUSION

We reported a high burden of thyroid cancer in Kerala, India, which is most likely due to overdiagnosis.

The role of race in thyroid cancer: systematic review

BACKGROUND

The incidence of thyroid cancer is increasing. There is conflicting evidence as to why. However, studies suggest that it is not an apparent increase resulting from enhanced diagnostic practices, but a true increase with more affected patients. This study aimed to assess racial variation in thyroid cancer.

METHOD

A narrative systematic review of the literature was conducted.

RESULTS

Eight retrospective cohort studies were identified, comprising 611 777 adult patients. Variations exist between racial groups, which are also dependent on gender; white patients have a slightly higher male population when compared to their counterparts. Black and white patients have a higher proportion of follicular cancer. Hispanics were younger at the age of diagnosis. Outcomes are greatly affected by socioeconomic status.

CONCLUSION

This study identified many gaps in the way that these types of data are presented. A more concise manner of reporting, with individual-level risk factors, is recommended.

Thyroid Cancer Epidemiology in Iran: a Time Trend Study

BACKGROUND

Considering the rising incidence of thyroid cancer worldwide, the aim of our study was to investigate the temporal trends in the incidence of this cancer in a large population of Iranian patients.

MATERIALS AND METHODS

We used the Iran Cancer Data System (ICDS) Registry to assess the thyroid cancer trend from 2004 to 2010 with regard to different genders, age groups, and morphologies. To do this we analyzed the data of 10,913 new cases of thyroid cancer that occurred during these years.

RESULTS

The incidence rate (per one year) of thyroid cancer was 2.20 per 100,000 persons between 2004 and 2010 in Iran. Papillary thyroid cancer was the most common histology type, with an annual rate of 0.29 in Iran. The highest rate of prevalence in thyroid cancer was observed at the age of 45 years at the time of diagnosis. We found a female-to-male ratio of 2 in Iran. A significant decrease was detected in the trend of thyroid cancer in children <19y, which was not correlated to the trend of older patients.

CONCLUSIONS

As expected, the trend of thyroid cancer increased over the 7 years, primarily contributed by papillary thyroid cancer. A rising pattern of incidence was seen in all the age groups except patients aged under 19 years.

A detailed spatial analysis on contrasting cancer incidence patterns in thyroid and lung cancer in Toronto women

Background

Thyroid cancer has been rapidly rising in incidence in Canada; however, in contrast, lung cancer appears to be decreasing in incidence in Canadian men and stable in women. Moreover, disease-related mortality risk is generally very low in TC but high in LC. We performed a geographic spatial analysis in metropolitan Toronto, Canada to determine if there is regional variability of respective risks of thyroid cancer (TC) and lung cancer (LC), among women. Women were of particular interest for this study, given their known predilection for thyroid cancer.

Methods

The postal codes of all females with TC or LC, residing in metropolitan Toronto from 2004 to 2008, were geocoded to point locations according to 2006 Canadian Census data. The data were analysed using a log-Gaussian Cox Process, where the intensity of age-adjusted cancer cases was modelled as a log-linear combination of the population at risk, explanatory variables (race, immigration, and median household income), and a residual spatially varying random effect. For each respective malignancy, statistical models were fit to make quantify the relationship between cancer incidence and explanatory variables.

Results

We included 2230 women with TC and 2412 with LC. The distribution of TC and LC cases contrasted inversely among Toronto neighbourhoods with the highest TC incidence in the Northeast and the highest LC incidence in the Southeast. A higher proportion of Asian ethnicity was associated with higher regional risk of TC and lower risk of LC. A higher proportion of recent immigrants was associated with increased LC and lower TC risk, whereas median household income and proportions of African ethnicity were not significantly associated with risk of either cancer, after adjustment for other socio-demographic variables.

Conclusions

We observed contrasting regional distributions of female TC and LC cases in Toronto. The differences were partly attributed to ethnic composition variability and the proportion of recent immigrants, but substantial unexplained residual variation of incidence patterns of these malignancies exists, suggesting that more individual-level research is needed to explain the regional variability of incidence of these malignancies.

Risk Factors for Thyroid Cancer: A Hospital-Based Case-Control Study in Korean Adults

PURPOSE

Although the incidence of thyroid cancer in Korea has rapidly increased over the past decade, few studies have investigated its risk factors. This study examined the risk factors for thyroid cancer in Korean adults.

MATERIALS AND METHODS

The study design was a hospital-based case-control study. Between August 2002 and December 2011, a total of 802 thyroid cancer cases out of 34,211 patients screened from the Cancer Screenee. Cohort of the National Cancer Center in South Korea were included in the analysis. A total of 802 control cases were selected from the same cohort, and matched individually (1:1) by age (±2 years) and area of residence for control group 1 and additionally by sex for control group 2.

RESULTS

Multivariate conditional logistic regression analysis using the control group 1 showed that females and those with a family history of thyroid cancer had an increased risk of thyroid cancer, whereas ever-smokers and those with a higher monthly household income had a decreased risk of thyroid cancer. On the other hand, the analysis using control group 2 showed that a family history of cancer and alcohol consumption were associated with a decreased risk of thyroid cancer, whereas higher body mass index (BMI) and family history of thyroid cancer were associated with an increased risk of thyroid cancer.

CONCLUSION

These findings suggest that females, those with a family history of thyroid cancer, those with a higher BMI, non-smokers, non-drinkers, and those with a lower monthly household income have an increased risk of developing thyroid cancer.

Method of Detection of Well-Differentiated Thyroid Cancers in Obese and Non-Obese Patients

BACKGROUND

The incidence of well-differentiated thyroid cancer (WDTC) is increasing rapidly. Many authors feel that this increase is due to over-diagnosis and that one of the contributing factors is the increasing use of various imaging studies. The rate of obesity has also been increasing in the United States. It has been suggested that patients with an increased body mass index (BMI kg/m2) have a higher incidence of WDTC than patients with normal BMI. One might hypothesize that thyroid nodules are more difficult to palpate in obese patients and that as more cancers are detected by imaging the apparent rate of increase in WDTC in obese patients would appear to be greater than in non-obese patients. This study was undertaken to evaluate this hypothesis by determining if there is any difference in the way thyroid cancers are initially detected in obese and non-obese patients.

METHODS

The medical records of all 519 patients with a postoperative diagnosis of WDTC who underwent thyroidectomy at NYU Langone Medical Center from January 1, 2007 through August 31, 2010 by the three members of NYU Endocrine Surgery Associates were reviewed. Patients were divided into Non-obese (BMI<30 kg/m2) and Obese (BMI≥30 kg/m2) groups. Patients were also divided by the initial method of detection of their tumor into Palpation, Imaging, and Incidental groups.

RESULTS

The final study group contained 270 patients, 181(67%) of whom were in the Non-obese Group and 89(33%) were in the Obese Group. In the Non-obese group, 81(45%) of tumors were found by palpation, 72(40%) were found by imaging, and 28(16%) were found incidentally. In the Obese group, 40(45%) were found by palpation, 38(43%) were found by imaging, and 11(12%) were found incidentally. These differences were not statistically significant (p-value 0.769).

CONCLUSION

We show that BMI does not play a role in the method of initial detection in patients with WDTC. This suggests that the prevalence of WDTC detected by imaging is not an artifact caused by an increasingly obese population and that any association of WDTC and obesity is not related to the way in which these tumors are detected.

Increasing thyroid cancer incidence in Queensland, Australia 1982-2008 - true increase or overdiagnosis?

BACKGROUND

Thyroid cancer incidence has been increasing worldwide. Some suggest greater ascertainment of indolent tumours is the only driver, but others suggest there has been a true increase. Increases in Australia appear to have been among the largest in the world, so we investigated incidence trends in the Australian state of Queensland to help understand reasons for the rise.

METHODS

Thyroid cancers diagnoses in Queensland 1982-2008 were ascertained from the Queensland Cancer Registry. We calculated age-standardized incidence rates (ASR) and used Poisson regression to estimate annual percentage change (APC) in thyroid cancer incidence by socio-demographic and tumour-related factors.

RESULTS

Thyroid cancer ASR in Queensland increased from 2·2 to 10·6/100 000 between 1982 and 2008 equating to an APC of 5·5% [95% confidence interval (CI) 4·7-6·4] in men and 6·1% (95% CI 5·5-6·6) in women. The rise was evident, and did not significantly differ, across socio-economic and remoteness-of-residence categories. The largest increase seen was in the papillary subtype in women (APC 7·9%, 95% CI 7·3-8·5). Incidence of localized and more advanced-stage cancers rose over time although the increase was greater for early-stage cancers.

CONCLUSION

There has been a marked increase in thyroid cancer incidence in Queensland. The increase is evident in men and women across all adult age groups, socio-economic strata and remoteness-of-residence categories as well as in localized and more advanced-stage cancers. Our results suggest 'overdiagnosis' may not entirely explain rising incidence. Contemporary aetiological data and individual-level information about diagnostic circumstances are required to further understand reasons for rising thyroid cancer incidence.

Socioeconomic Factors Affect Outcomes in Well-Differentiated Thyroid Cancer

OBJECTIVES

The effects of socioeconomic status (SES) on the incidence of well-differentiated thyroid cancer (WDTC) are well researched. However, the association between SES and outcomes is not delineated. Our objective was to determine if SES affected outcomes of WDTC.

STUDY DESIGNS

Retrospective database review.

SETTING

Tertiary care medical center.

SUBJECTS AND METHODS

The Henry Ford Virtual Data Warehouse Tumor Registry was used to identify cases of WDTC. Socioeconomic data were obtained through the 2010 US Census: median household income, percentage below poverty line, median household size, percentage rent versus own property, and general demographics. Survival was the primary outcome. Disease-specific survival was also calculated. Cox proportional hazards were calculated and a multivariate analysis performed.

RESULTS

There were 1317 patients with WDTC. In multivariable analysis, median household income (hazard ratio [HR]: 0.85, 95% confidence interval [95% CI]: 0.79-0.91), household size (HR: 1.49, 95% CI: 1.09-2.14), younger age (HR: 1.97, 95% CI: 1.74-2.23), and female sex (HR: 0.50, 95% CI: 0.37-0.69) were significantly associated with survival. Controlling for stage revealed percentage below poverty line (stage I, HR: 0.51, 95% CI: 1.34-1.78; stage IV, HR: 1.28, 95% CI: 1.04-1.57) and median household income (HR: 0.84, 95% CI: 0.71-0.99) to be significant factors in survival. Median household income was a statistically significant variable for disease-related death (HR: 0.82, 95% CI: 0.69-0.96) CONCLUSIONS: Along with effects on incidence, lower SES correlates with worse survival in WDTC. This suggests that a patient's economic background, with younger age and female sex, influences one's outcomes with regard to both overall and disease-specific death.

Tobacco Withdrawal Amongst African American, Hispanic, and White Smokers

INTRODUCTION

Persistent tobacco use among racial and ethnic minority populations in the United States is a critical public health concern. Yet, potential sources of racial/ethnic disparities in tobacco use remain unclear. The present study examined racial/ethnic differences in tobacco withdrawal-a clinically-relevant underpinning of tobacco use that has received sparse attention in the disparities literature-utilizing a controlled laboratory design.

METHODS

Daily smokers (non-Hispanic African American [n = 178], non-Hispanic white [n = 118], and Hispanic [n = 28]) attended two counterbalanced sessions (non-abstinent vs. 16-hour abstinent). At both sessions, self-report measures of urge, nicotine withdrawal, and affect were administered and performance on an objective behavioral task that assessed motivation to reinstate smoking was recorded. Abstinence-induced changes (abstinent scores vs. non-abstinent scores) were analyzed as a function of race/ethnicity.

RESULTS

Non-Hispanic African American smokers reported greater abstinence-induced declines in several positive affect states in comparison to other racial/ethnic groups. Relative to Hispanic smokers, non-Hispanic African American and non-Hispanic white smokers displayed larger abstinence-provoked increases in urges to smoke. No racial/ethnic differences were detected for a composite measure of nicotine withdrawal symptomatology, negative affect states, and motivation to reinstate smoking behavior.

CONCLUSIONS

These results suggest qualitative differences in the expression of some components of tobacco withdrawal across three racial/ethnic groups. This research helps shed light on bio-behavioral sources of tobacco-related health disparities, informs the application of smoking cessation interventions across racial/ethnic groups, and may ultimately aid the overall effort towards reducing the public health burden of tobacco addiction in minority populations.

IMPLICATIONS

The current study provides some initial evidence that there may be qualitative differences in the types of tobacco withdrawal symptoms experienced among non-Hispanic African American, Hispanic, and non-Hispanic white smokers. Extending this line of inquiry may elucidate mechanisms involved in tobacco-related health disparities and ultimately aid in reducing the public health burden of smoking in racial/ethnic minority populations.

Gender, Ethnicity, and Their Intersectionality in the Prediction of Smoking Outcome Expectancies in Regular Cigarette Smokers

The current study utilized the intersectionality framework to explore whether smoking outcome expectancies (i.e., cognitions about the anticipated effects of smoking) were predicted by gender and ethnicity, and the gender-by-ethnicity interaction. In a cross-sectional design, daily smokers from the general community (32.2% women; non-Hispanic African American [n = 175], non-Hispanic White [n = 109], or Hispanic [n = 26]) completed self-report measures on smoking expectancies and other co-factors. Results showed that women reported greater negative reinforcement (i.e., anticipated smoking-induced negative affect reduction) and weight control (i.e., anticipated smoking-induced appetite/weight suppression) expectancies than men. Hispanic (vs. African American or White) smokers endorsed greater negative reinforcement expectancies. A gender-by-ethnicity interaction was found for weight control expectancies, such that White women reported greater weight control expectancies than White men, but no gender differences among African American and Hispanic smokers were found. These findings suggest that gender, ethnicity, and their intersectionality should be considered in research on cognitive mechanisms that may contribute to tobacco-related health disparities.

The Impact of Diagnostic Changes on the Rise in Thyroid Cancer Incidence: A Population-Based Study in Selected High-Resource Countries

BACKGROUND

Thyroid cancer (TC) incidence is rising in many countries, but the corresponding mortality is constant or declining. Incidence increases appear largely restricted to small papillary TC in young/middle-age individuals. We compared age-specific incidence rates across countries and time periods in order to estimate the fraction of TC possibly attributable to increased surveillance of the thyroid gland (diagnostic changes) following the introduction of neck ultrasonography in the 1980s.

METHODS

We focused on high-resource countries, including four Nordic countries, England and Scotland, France, Italy, the United States, Australia, Japan, and the Republic of Korea. Before the 1970s, TC incidence in Nordic countries increased proportionally to the second power of age, consistent with the multistage model of carcinogenesis. Using this historical observation for reference, we attributed the progressive departure from linearity of the age curves in each country to an increased detection of asymptomatic disease in young/middle-age individuals. The proportion of cases attributable to diagnostic changes was estimated from the difference between observed rates and those expected using the Nordic countries as reference.

RESULTS

Diagnostic changes may account for ≥60% of TC cases diagnosed in 2003-2007 in women aged under 80 years in France, Italy, the United States, Australia, and the Republic of Korea, and approximately 50% in other assessed countries, except Japan (30%). The proportions attributable to diagnostic changes were higher in countries with largest incidence increases and were consistent across sexes, although increases were smaller and delayed in men.

CONCLUSIONS

A large proportion of TC cases diagnosed in high-resource countries in the last two decades are likely to be due to diagnostic changes. This proportion has progressively increased over time, and it is likely to grow further in the future. Since there is evidence of harm but no proof of benefit from the intense scrutiny of the thyroid, the dangers of overdiagnosis and overtreatment of TC should be urgently addressed.

Overdiagnosis of thyroid cancer: answers to five key questions

Thyroid cancer fulfills the criteria for overdiagnosis by having a reservoir of indolent cancers and practice patterns leading to the diagnosis of incidental cancers from the reservoir. The occurrence of overdiagnosis is also supported by population-based data showing an alarming rise in thyroid cancer incidence without change in mortality. Because one of the activities leading to overdiagnosis is the workup of incidental thyroid nodules detected on imaging, it is critical that radiologists understand the issue of overdiagnosis and their role in the problem and solution. This article addresses 1) essential thyroid cancer facts, 2) the evidence supporting overdiagnosis, 3) the role of radiology in overdiagnosis, 4) harms of overdiagnosis, and 5) steps radiologists can take to minimize the problem.

The changing epidemiology of thyroid cancer: why is incidence increasing?

PURPOSE OF REVIEW

Thyroid cancer incidence is increasing worldwide. Causes are highly debated.

RECENT FINDINGS

Thyroid cancer increase has been associated to socioeconomic status, better access to healthcare and rising use of thyroid imaging. Therefore, the rise could be apparent because of the useless identification of a large reservoir of subclinical papillary lesions that will never affect patient health (overdiagnosis).However, not all epidemiological and clinical data support this hypothesis. The increasing number of large tumors, the increasing thyroid cancer-related mortality in spite of earlier treatment and the changes in thyroid cancer molecular profile suggest a true increase. Recently increased and thyroid-specific environmental carcinogens could be responsible, such as radiation (mostly medical radiation), increased iodine intake and chronic lymphocytic thyroiditis and environmental pollutants such as nitrates, heavy metals and other compounds largely used in the industrialized society. Possible mechanisms await further investigation.

SUMMARY

The increased incidence of thyroid cancer is the likely result of two coexisting processes: increased detection (apparent increase) and increased number of cases (true increase) due to unrecognized thyroid-specific carcinogens.To identify causal factors and to differentiate stationary cancers from those that will progress are major urgent requirements for both clinical and scientific purposes.

Geospatial and Temporal Analysis of Thyroid Cancer Incidence in a Rural Population

BACKGROUND

The increasing incidence of thyroid cancer has resulted in the rate tripling over the past 30 years. Reasons for this increase have not been established. Geostatistics and geographic information system (GIS) tools have emerged as powerful geospatial technologies to identify disease clusters, map patterns and trends, and assess the impact of ecological and socioeconomic factors (SES) on the spatial distribution of diseases. In this study, these tools were used to analyze thyroid cancer incidence in a rural population.

METHODS

Thyroid cancer incidence and socio-demographic factors in Vermont (VT), United States, between 1994 and 2007 were analyzed by logistic regression and geospatial and temporal analyses.

RESULTS

The thyroid cancer age-adjusted incidence in Vermont (8.0 per 100,000) was comparable to the national level (8.4 per 100,000), as were the ratio of the incidence of females to males (3.1:1) and the mortality rate (0.5 per 100,000). However, the estimated annual percentage change was higher (8.3 VT; 5.7 U.S.). Incidence among females peaked at 30-59 years of age, reflecting a significant rise from 1994 to 2007, while incidence trends for males did not vary significantly by age. For both females and males, the distribution of tumors by size did not vary over time; ≤1.0 cm, 1.1-2.0 cm, and >2.0 cm represented 38%, 22%, and 40%, respectively. In females, papillary thyroid cancer (PTC) accounted for 89% of cases, follicular (FTC) 8%, medullary (MTC) 2%, and anaplastic (ATC) 0.6%, while in males PTC accounted for 77% of cases, FTC 15%, MTC 1%, and ATC 3%. Geospatial analysis revealed locations and spatial patterns that, when combined with multivariate incidence analyses, indicated that factors other than increased surveillance and access to healthcare (physician density or insurance) contributed to the increased thyroid cancer incidence. Nine thyroid cancer incidence hot spots, areas with very high normalized incidence, were identified based on zip code data. Those locations did not correlate with urban areas or healthcare centers.

CONCLUSIONS

These data provide evidence of increased thyroid cancer incidence in a rural population likely due to environmental drivers and SES. Geospatial modeling can provide an important framework for evaluation of additional associative risk factors.

Initial treatment patterns in younger adult patients with differentiated thyroid cancer in California

BACKGROUND

Differentiated thyroid cancer (DTC) is among the most common malignancies in the adolescent and young adult (age 15-39 years) population, and its incidence is rising. Younger age (<45 years) is an important prognostic indicator and is incorporated into the TNM classification system. This study hypothesized that this would result in distinct treatment patterns for younger and older patients.

METHODS

Using the California Cancer Registry, 24,362 patients with DTC from 2004 to 2011 were identified, and they were divided into younger (<45 years) and older (≥45 years) cohorts. Demographic and clinical variables were tabulated and then compared using chi-square tests. Treatment variables included total or near total thyroidectomy, other types of thyroid surgery, and the administration of radioiodine as part of the initial treatment. Multivariable logistic regression was used to identify independent predictors of treatment administered.

RESULTS

Younger patients were more likely to be Hispanic (32.5% vs. 21.2%) and female (82.7% vs. 74.7%), and to have papillary carcinoma (92.9% vs. 90.9%) and lymph node involvement (32.8% vs. 19.7%; p<0.0001). On multivariable analysis, younger patients (OR 1.20 [CI 1.11-1.30]), higher T-stage tumors, higher socioeconomic status (SES), and papillary carcinoma were predictors of undergoing total thyroidectomy versus less than total thyroid surgery. After adjustment, predictors of radioiodine administration included younger age (OR 1.12 [CI 1.05-1.18]), higher SES, total thyroidectomy, higher T stage, and lymph node positivity.

CONCLUSIONS

Younger patients with DTC in California are more likely to be female and Hispanic with papillary histology. After adjustment for disease and demographic characteristics, younger patients are more likely to undergo total thyroidectomy as their initial surgery and are more likely to receive radioiodine. Given their excellent prognosis and the potential for adverse sequelae from initial treatment for DTC, these findings warrant consideration when managing younger patients with DTC.

Increased thyroid cancer incidence corresponds to increased use of thyroid ultrasound and fine-needle aspiration: a study of the Veterans Affairs health care system

BACKGROUND

Thyroid cancer incidence has increased in the last several decades and may represent either a true increase in the number of cases or increased screening. The objective of this study was to examine thyroid cancer incidence and the use of thyroid ultrasound and fine-needle aspiration (FNA) screening in the Veterans Affairs (VA) health care system. The authors hypothesized that the incidence of thyroid cancer would correspond to increases in the use of these diagnostic modalities.

METHODS

This was a multiyear, cross-sectional study using VA administrative data from 2000 to 2012. Joinpoint regression analysis was used to identify trends in thyroid cancer incidence and the use of thyroid ultrasound and FNA.

RESULTS

An increase in thyroid cancer incidence occurred from 10.3 per 100,000 individuals in 2000 to 21.5 per 100,000 individuals in 2012. The rate of thyroid ultrasound use increased from 125.6 per 100,000 individuals in 2001 to 572.1 per 100,000 individuals in 2012, and the rate of thyroid FNA use increased from 7.0 per 100,000 individuals in 2000 to 46.2 per 100,000 individuals in 2012. A statistically significant increase in thyroid cancer incidence between 2000 and 2008 (annual percent change [APC], 3.81; P < .05) was followed by a more pronounced increase between 2008 and 2012 (APC, 10.32; P < .05). A simultaneous increase in the use of thyroid ultrasound occurred between 2002 and 2012 (APC, 15.48; P < .05) and the use of thyroid FNA between 2000 and 2012 (APC, 18.36; P < .05).

CONCLUSIONS

Although the incidence of thyroid cancer doubled, a nearly 5-fold increase in the use of thyroid ultrasound and a nearly 7-fold increase in the use of thyroid FNA occurred between 2000 and 2012. These findings suggest that the increase in thyroid cancer incidence may be related to increases in the use of thyroid ultrasound and FNA.

Predictors for thyroid carcinoma in Israel: a national cohort of 1,624,310 adolescents followed for up to 40 years

INTRODUCTION

Data on adolescent precursors of thyroid cancer in adulthood are scant.

METHODS

In order to evaluate potential risk factors for thyroid cancer, we linked two national data sources: the military recruitment health examinations and the Israel National Cancer Register. The study population (1,624,310 participants) included 1,145,865 Jewish males aged 16-19 years when examined between 1967 and 2005, and 478,445 Jewish females aged 16-19 years when examined between 1989 and 2005. The cancer follow-up extended up to 2006. Multivariable Cox proportional hazards modeling was used.

RESULTS

During 24,389,502 person years of follow-up, 760 incidence cases of thyroid cancer were identified. The mean age at diagnosis was 25.2±4.2 years for women and 37.2±10.0 years for men. Women had a substantially higher incidence (birth cohort-adjusted hazard ratio (HR)=5.70 [95% CI 4.45-7.31]; p<0.001). Height predicted incidence in both sexes, with birth cohort-adjusted HRs of 1.03 (p<0.001) in males and 1.04 (p<0.001) in females, per 1 cm increment in height. In males, but not in females, there was a graded association between education, as measured by years of schooling, and incidence of thyroid cancer. Body mass index was not associated with incidence. In a multivariable analysis of 617,613 males and 469,185 females examined from 1989 onwards, which included sex, birth year, height, and education, the excess risk in females persisted strongly (HR=5.67 [CI 4.30-7.13]), as did the association with height.

CONCLUSIONS

Female sex, measured height in adolescence, and later birth cohorts were independent predictors of thyroid cancer in young and middle-aged adults in Israel. Further study is needed to unravel the mechanisms whereby height is associated with thyroid cancer.