Increasing world incidence of thyroid cancer: increased detection or higher radiation exposure?

CHIP promotes thyroid cancer proliferation via activation of the MAPK and AKT pathways

The carboxyl terminus of Hsp70-interacting protein (CHIP) is a U box-type ubiquitin ligase that plays crucial roles in various biological processes, including tumor progression. To date, the functional mechanism of CHIP in thyroid cancer remains unknown. Here, we obtained evidence of upregulation of CHIP in thyroid cancer tissues and cell lines. CHIP overexpression markedly enhanced thyroid cancer cell viability and colony formation in vitro and accelerated tumor growth in vivo. Conversely, CHIP knockdown impaired cell proliferation and tumor growth. Notably, CHIP promoted cell growth through activation of MAPK and AKT pathways, subsequently decreasing p27 and increasing cyclin D1 and p-FOXO3a expression. Our findings collectively indicate that CHIP functions as an oncogene in thyroid cancer, and is therefore a potential therapeutic target for this disease.

Predicting malignancy in thyroid nodules: feasibility of a predictive model integrating clinical, biochemical, and ultrasound characteristics

Background

Although the majority of thyroid nodules are benign the process of excluding malignancy is challenging and sometimes involves unnecessary surgical procedures. We explored the development of a predictive model for malignancy in thyroid nodules by integrating a combination of simple demographic, biochemical, and ultrasound characteristics.

Methods

Retrospective case-record review.

We reviewed records of patients with thyroid nodules referred to our institution from 2004 to 2011 (n = 536; female 84 %, mean age 51 years). All malignancy was proven histologically while benign disease was either confirmed histologically, or on cytology with minimum 36-month observation period. We focused on the following predictors: age, sex, smoking status, thyroid hormones (FT4 and TSH) and nodule characteristics on ultrasound. Variables were included in a multivariate logistic regression and bootstrap analyses were used to confirm results.

Results

Independent predictors of malignancy in the fully adjusted model were TSH (OR 1.53, 95 % CI 1.10, 2.12, p = 0.01), male gender (OR 3.45, 95 % CI 1.33, 8.92, p = 0.01), microcalcifications (OR 6.32, 95 % CI 2.82, 14.1, p < 0.001), and irregular nodule margins (OR 5.45, 95 % CI 1.61, 18.6, p = 0.006) Bootstrap analyses strengthened these associations and a parsimonious analysis consisting of these variables and age-group demonstrated an area under the curve of 0.77. A predictive score was sensitive (86.9 %) at low scores and highly specific (94.87 %) at higher scores for distinguishing benign from malignant disease.

Conclusions

A predictive model for malignancy using a combination of clinical, biochemical, and radiological characteristics may support clinicians in reducing unnecessary invasive procedures in patients with thyroid nodules.

Electronic supplementary material

The online version of this article (doi:10.1186/s13044-016-0033-y) contains supplementary material, which is available to authorized users.

Trends of Thyroid Cancer in Israel: 1980-2012

OBJECTIVES

Thyroid cancer incidence is increasing worldwide, while mortality from thyroid cancer is stable or decreasing. Consequently, survival rates are rising. We describe time trends in the incidence, mortality, and 5-year survival of thyroid cancer in Israel in 1980-2012, in light of the global trends.

METHODS

Israel National Cancer Registry database provided information regarding thyroid cancer incidence and vital status, which enabled computation of survival rates. The Central Bureau of Statistics database provided information on thyroid cancer mortality. Incidence and mortality rates were age-adjusted and presented by population group (Jews/Arabs) and gender. Relative 5-year survival rates which account for the general population survival in the corresponding time period were presented by population group and gender. Joinpoint analyses were used to assess incidence trends over time.

RESULTS

In 1980-2012 significant increases in the incidence of thyroid cancer were observed, with an annual percent change (APC) range of 3.98-6.93, driven almost entirely by papillary carcinoma (APCs 5.75-8.86), while rates of other types of thyroid cancer remained stable or decreased. Furthermore, higher rates of early detection were noted. In 1980-2012, a modest reduction in thyroid cancer mortality was observed in Jewish women (APC -1.07) with no substantial change in Jewish men. The 5-year relative survival after thyroid cancer diagnosis has increased to ≥90% in both population groups and both genders.

CONCLUSIONS

The Israeli secular trends of thyroid cancer incidence (increasing), mortality (mostly stable), and survival (modestly increasing) closely follow reported global trends.

Psychological and behavioral intervention improves the quality of life and mental health of patients suffering from differentiated thyroid cancer treated with postoperative radioactive iodine-131

BACKGROUND

We examined the effects of psychological and behavioral intervention on health-related quality of life and mental health among patients suffering from differentiated thyroid cancer (DTC) treated with postoperative radioactive iodine-131 (RAI).

METHODS

Sixty patients with DTC, undergoing RAI, were randomly assigned to receive either conventional nursing (n=30) or a 1-year psychological and behavioral intervention based on conventional nursing (n=30). Health-related quality of life and mental health issues, depression, and anxiety were measured using the Quality of Life Core Questionnaire, Self-rating Depression Scale, and Self-rating Anxiety Score, respectively.

RESULTS

After RAI treatment, patients in both groups showed improved functional capacities (ie, physical, role, cognitive, emotional, and social) and global quality of life, along with reduced depression and anxiety (P<0.05). At 1-year follow-up, compared with patients in the routine nursing group, those in the psychological and behavioral intervention group demonstrated greater improvements in functional capacities, global quality of life, and depression and anxiety symptoms (P<0.05).

CONCLUSION

Psychological and behavioral interventions for patients with DTC undergoing RAI facilitated positive outcomes, suggesting that nursing care models that include psychological and behavioral interventions may be a complementary strategy for this patient population.

Parity and thyroid cancer risk: a meta-analysis of epidemiological studies

Although observational studies have assessed the relationship between parity and thyroid cancer risk, the findings are inconsistent. To quantitatively assess the association, we conducted a systematic review and meta-analysis. PubMed and Embase were searched up to January 2015. Prospective or case-control studies that evaluated the association between parity and thyroid cancer risk were included. We used the fixed-effects model to pool risk estimates. After literature search, 10 prospective studies, 12 case-control studies and 1 pooled analysis of 14 case-control studies including 8860 patients were identified. The studies had fair methodological quality. Pooled analysis suggested that there was a significant association between parity and risk of thyroid cancer (RR for parous versus nulliparous: 1.09, 95% CI 1.03-1.15; I2=33.4%). The positive association persisted in almost all strata of subgroup analyses based on study design, location, study quality, type of controls, and confounder adjustment, although in some strata statistical significance was not detected. By evaluating the number of parity, we identified that both parity number of 2 versus nulliparous and parity number of 3 versus nulliparous demonstrated significant positive associations (RR=1.11, 95% CI 1.01-1.22; I2=31.1% and RR=1.16, 95% CI 1.01-1.33; I2=19.6% respectively). The dose-response analysis suggested neither a non-linear nor linear relationship between the number of parity and thyroid cancer risk. In conclusion, this meta-analysis suggests a potential association between parity and risk of thyroid cancer in females. However, the lack of detection of a dose-response relationship suggests that further studies are needed to better understand the relationship.

Effect of cell phone-like electromagnetic radiation on primary human thyroid cells

PURPOSE

To evaluate the potential carcinogenic effects of radiofrequency energy (RFE) emitted by cell phones on human thyroid primary cells.

MATERIALS AND METHODS

Primary thyroid cell culture was prepared from normal thyroid tissue obtained from patients who underwent surgery at our department. Subconfluent thyroid cells were irradiated under different conditions inside a cell incubator using a device that simulates cell phone-RFE. Proliferation of control and irradiated cells was assessed by the immunohistochemical staining of antigen Kiel clone-67 (Ki-67) and tumor suppressor p53 (p53) expression. DNA ploidy and the stress biomarkers heat shock protein 70 (HSP70) and reactive oxygen species (ROS) was evaluated by fluorescence-activated cell sorting (FACS).

RESULTS

Our cells highly expressed thyroglobulin (Tg) and sodium-iodide symporter (NIS) confirming the origin of the tissue. None of the irradiation conditions evaluated here had an effect neither on the proliferation marker Ki-67 nor on p53 expression. DNA ploidy was also not affected by RFE, as well as the expression of the biomarkers HSP70 and ROS.

CONCLUSION

Our conditions of RFE exposure seem to have no potential carcinogenic effect on human thyroid cells. Moreover, common biomarkers usually associated to environmental stress also remained unchanged. We failed to find an association between cell phone-RFE and thyroid cancer. Additional studies are recommended.

Breastfeeding and thyroid cancer risk in women: A dose-response meta-analysis of epidemiological studies

BACKGROUND & AIMS

The association between breastfeeding and thyroid cancer risk is not consistent from epidemiological studies. To better clarify the association including assessing a potential dose-response relationship, we conducted a comprehensive meta-analysis.

METHODS

We searched PubMed (MEDLINE) up to November 2015 for prospective studies or case-control studies that evaluated the association between breastfeeding and risk of thyroid cancer. Effect estimates were pooled using a fixed-effects model.

RESULTS

Nine reports (2 prospective studies, 6 case-control studies and 1 pooled analysis of 14 case-control studies) involving 2423 cases and 350,081 non-cases were identified. After pooling relevant studies, there was a significant inverse association between ever breastfeeding and risk of thyroid cancer (RR = 0.91, 95% CI 0.83-0.99), with minor heterogeneity (I(2) = 10.1%). The dose-response analysis revealed a significant linear relationship between the duration of breastfeeding and risk of thyroid cancer. The summary RR for an increment of 1 month of breastfeeding with risk of thyroid cancer was 0.983 (95% CI 0.98-0.99). When focusing on cohort studies, a more prominent linear dose-response relationship was detected, with the combined RR for every increment of 1 month of breastfeeding to be 0.965 (95% CI 0.96-0.97).

CONCLUSIONS

This meta-analysis suggests that breastfeeding is potentially inversely associated with thyroid cancer risk. Also longer duration of breastfeeding may further decreases thyroid cancer risk. If validated in large-scale prospective studies, our findings may have implications for impacting women's decision in breastfeeding.

Patterns of Benign and Malignant Lesions of the Thyroid in Two Wilayahs of Northeastern Algeria

The aim of this study is to compare histological patterns and to estimate the burden of thyroid cancers in the two Wilayahs (departments) of El-Taref and Guelma in northeast of Algeria (total population 0.9 million), locally reputed as having different rates of endemic thyroid diseases and cancer. A retrospective analysis of central pathology registers and clinical records of patients with thyroid diseases, covering the period 2008-2012, was conducted. A total of 145 cases of thyroid cancers with histological confirmation were registered in the two Wilayahs during the period, with a female to male ratio of 5.9 : 1. Estimates of crude incidence rates suggested that thyroid cancers were twice as frequent in the Wilayah of Guelma compared to El-Taref (p < 0.05) with a tendency to occur at a younger age in resident of the Wilayah of El-Taref. Diagnoses of thyroid adenoma were more frequent in the Wilayah of Guelma, whereas the prevalence of other thyroid lesions, including goitre, was similar in the two Wilayahs. This first descriptive study on geographic variations in thyroid cancer in Northern Africa suggests that significant differences may occur in relation with environmental and lifestyle exposures.

A Clinical Trial of Optimal Time Interval Between Ablation and Diagnostic Activity When a Pretherapy RAI Scanning Is Performed on Patients With Differentiated Thyroid Carcinoma

This article investigates the association of the time interval between the diagnostic dose and ablation with the stunning effect, when a 74 MBq I pretherapy scanning was performed on patients with differentiated thyroid carcinoma (DTC); the patients who were diagnosed as DTC and would be performed radioiodine (RAI) ablation of thyroid remnants or metastases were recruited during January 2011 and May 2012 in our hospital.Thirty-seven patients with DTC who had the RAI ablation of thyroid remnants or metastases for the first time were recruited. All the patients received a dose of 1850 to 7400 MBq of I for ablation and a diagnostic scan was performed 24 hours after the administration of 74 MBq I before ablation. A posttherapy scan was performed 2 to 7 days after the ablation. The patients were broken down into 3 groups (G1, G2, and G3) according to the interval time between the diagnostic dose and therapy (1-3, 4-7, and >7 days). The fractional concentrations of I in remnants or functional metastases were quantified and expressed as therapeutic/diagnostic (Rx/Dx). The level of significance was set at 0.05.Sixty-seven foci were found both on pretherapy and posttherapy scans, the mean ratio of Rx/Dx was 0.43 ± 0.29, and the ratio of 49 foci (73.13%) was <0.6. The ratios in G1, G2, and G3 were 0.46 ± 0.29, 0.29 ± 0.18, and 0.55 ± 0.33, respectively. The differences between G1 and G2, and G2 and G3 were statistically significant (t = 2.40, P = 0.021 and t = 3.28, P = 0.002), whereas the difference between G1 and G3 was not significant (t = 1.01, P = 0.319).By a diagnostic scan of 74 MBq I, stunning prominently occurs with a time of 4 to 7 days between the diagnostic dose and ablation. We recommend that for less stunning effect, RAI ablation should be performed within 3 days or postponed until 1 week after the diagnostic dose administrated.

Linear reduction in thyroid cancer risk by oral contraceptive use: a dose-response meta-analysis of prospective cohort studies

STUDY QUESTION

Is there an association between oral contraceptive (OC) use and thyroid cancer risk in females?

SUMMARY ANSWER

OC use is inversely associated with the risk of thyroid cancer in females.

WHAT IS KNOWN ALREADY

OC use may be relevant to the risk of thyroid cancer as suggested by some epidemiological studies. However, the findings are inconsistent regarding the effect direction and size.

STUDY DESIGN, SIZE, DURATION

This systematic review and meta-analysis included a total of 1906 patients from about 1.3 million individuals who had participated in 9 prospective cohort studies. The follow-up length ranged 7.5-15.9 years.

PARTICIPANTS/MATERIALS, SETTING, METHODS

PubMed (MEDLINE) was searched through to January 2015 for eligible studies. References of relevant review articles were also manually screened. Prospective cohort studies that evaluated the association between OC use and thyroid cancer risk were included. Study characteristics including patients' characteristics, length of the follow-up and risk estimates were extracted. The quality of the studies was also assessed.

MAIN RESULTS AND THE ROLE OF CHANCE

The included studies were of high methodological quality according to the Newcastle-Ottawa Quality Assessment Scale. After pooling risk estimates from all the studies, there was a significant inverse association between the longest versus shortest duration of OC use and the risk of thyroid cancer [relative risk (RR) = 0.84, 95% confidence interval (CI) 0.73-0.97], with no considerable heterogeneity (I(2) = 26.1%). There was no significant publication bias. The significant association persisted in the subgroup of high-quality studies (RR = 0.84, 95% CI 0.72-0.97). By dose-response analysis, there was a linear relationship (P = 0.0001) between the duration of OC use and thyroid cancer risk. The summary RR for an increment of 1 year of OC use was 0.96 (95% CI 0.94-0.98), with no significant heterogeneity.

LIMITATIONS, REASONS FOR CAUTION

Individual patient data were unavailable for a more accurate estimation.

WIDER IMPLICATIONS OF THE FINDINGS

These results indicate that OC use may decrease the risk of thyroid cancer in females. This may have implications for women's decisions regarding the use of OC.

STUDY FUNDING/COMPETING INTERESTS

No funding was involved for this study. No conflicts of interest are declared.

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.

Time trends and age-period-cohort analyses on incidence rates of thyroid cancer in Shanghai and Hong Kong

Background

Increasing incidence rates of thyroid cancer have been noted worldwide, while the underlying reasons remain unclear.

Methods

Using data from population-based cancer registries, we examined the time trends of thyroid cancer incidence in two largest cities in China, Shanghai and Hong Kong, during the periods 1973–2009 and 1983–2011, respectively. We further performed age-period-cohort analyses to address the possible underlying reasons for the observed temporal trends.

Results

We observed continuous increases in the incidence rates of thyroid cancer in Shanghai and Hong Kong, since the 1980s, in addition to higher incidence rates in the 1970s in both sexes in Shanghai. The age-standardized incidence rate of thyroid cancer increased by 3.1% [95% confidence interval (CI): 1.0%, 5.1%] and 3.8% (95% CI: 1.9%, 5.7%) per year on average, respectively, in Shanghai men and women during the period 1973–2009, while it increased by 2.2% (95% CI: 1.5%, 2.8%) and 2.7% (1.6%, 3.8%) per year on average, respectively, in Hong Kong men and women during the period 1983–2011. We observed global changes in trends across all age groups in similar ways, in addition to varied trends across different generations (birth cohorts).

Conclusions

The increased incidence rates of thyroid cancer in these two Chinese populations during recent decades may be contributable to a combination of the introduction of more sensitive diagnostic techniques and the increasing prevalence of environmental exposures in the populations.

Incidence rate of thyroid cancer in Neuquén (2001-2012)

During the past decades, an increasing incidence of thyroid cancer (TC) has been reported worldwide. In Argentina there is no national cancer registry, and its incidence has therefore not been established. The aim of our study was to determine the incidence of TC in the province of Neuquén and to compare it to that reported in the literature. The medical records of 229 patients admitted over a period of 12 years (2001 to 2012) were used for data analysis. Tumor size, age, sex, and histological type were evaluated. The study period was divided into four three-year periods, and differences in each of these features were analyzed. We found an incidence of 4.72/100,000 inhabitants/year, and almost all patients had papillary TC. TC was five times more common in females as compared to males (7.78 and 1.55 respectively). Mean tumor size was 22.2 ± 1.1 mm. Tumor size was significantly greater in men (31.8 ± 3.7 mm) than in women (20.4 ± 1.0 mm). When grouped by three-year periods, a higher number of cases was found in the last one (47, 49, 49 and 84 respectively). As regards tumor distribution by size, there was a significant decrease in mean tumor size in the fourth period and an increase in the proportion of tumors <10mm. We report an increase in TC incidence in the Argentinean province of Neuquén which is similar to the overall increase reported in the international literature.

The influence of the environment on the development of thyroid tumors: a new appraisal

Most epidemiological studies concerning differentiated thyroid cancers (DTC) indicate an increasing incidence over the last two decades. This increase might be partially explained by the better access to health services worldwide, but clinicopathological analyses do not fully support this hypothesis, indicating that there are carcinogenetic factors behind this noticeable increasing incidence. Although we have undoubtedly understood the biology and molecular pathways underlying thyroid carcinogenesis in a better way, we have made very little progresses in identifying a risk profile for DTC, and our knowledge of risk factors is very similar to what we knew 30-40 years ago. In addition to ionizing radiation exposure, the most documented and established risk factor for DTC, we also investigated the role of other factors, including eating habits, tobacco smoking, living in a volcanic area, xenobiotics, and viruses, which could be involved in thyroid carcinogenesis, thus, contributing to the increase in DTC incidence rates observed.

Papillary Thyroid Cancer and Hashimoto's Thyroiditis: An Association Less Understood

Hashimoto's thyroiditis (HT), part of the spectrum of autoimmune thyroid diseases is a major cause of thyroid hypofunction worldwide. Papillary thyroid carcinoma (PTC), the most prevalent of all thyroid carcinomas has been associated with HT. Literature on this association are based on preoperative FNA or post thyroidectomy histopathology reports, which are subject to potential biases. Molecular, hormonal and histopathalogical basis of this association has been hypothesized, however a definite causal association has not been proved till date. This review aims to study the basis of this association and clinical features and management of HT concurrent with PTC. There are no distinctive clinical or radiological features that categorically differentiates HT concurrent with PTC from PTC or which can pick up a nodule harboring PTC in setting of HT. Smaller nodule size and radiological features like hypoechogenecity; hyper vascularity and calcification in a clinical setting of hypothyroidism have a higher odds ratio for malignancy and merit further investigations. PTC associated with HT has been seen to be less aggressive with earlier presentation with lesser chances of extra thyroidal extension and lymph nodal metastasis. The management and follow up of PTC in HT is no different from that of PTC alone. The prognosis of PTC concurrent with HT is better compared to age and stage matched PTC in terms of lower recurrence and disease free and overall survival.

The role of the inflammatory microenvironment in thyroid carcinogenesis

Immune responses against thyroid carcinomas have long been demonstrated and associations between inflammatory microenvironment and thyroid carcinomas repeatedly reported. This scenario has prompted scientists throughout the world to unveil how the inflammatory microenvironment is established in thyroid tumors and what is its influence on the outcome of patients with thyroid carcinoma. Many studies have reported the role of evasion from the immune system in tumor progression and reinforced the weakness of the innate immune response toward thyroid cancer spread in advanced stages. Translational studies have provided evidence that an increased density of tumor-associated macrophages in poorly differentiated thyroid carcinoma (DTC) is associated with an aggressive phenotype at diagnosis and decreased cancer-related survival, whereas well-DTC microenvironment enriched with macrophages is correlated with improved disease-free survival. It is possible that these different results are related to different microenvironments. Several studies have provided evidence that patients whose tumors are not infiltrated by lymphocytes present a high recurrence rate, suggesting that the presence of lymphocytes in the tumor microenvironment may favor the prognosis of patients with thyroid carcinoma. However, the effect of lymphocytes and other immune cells on patient outcome seems to result from complex interactions between the tumor and immune system, and the molecular pattern of cytokines and chemokines helps to explain the involvement of the immune system in thyroid tumor progression. The inflammatory microenvironment may help to characterize aggressive tumors and to identify patients who would benefit from a more invasive approach, probably sparing the vast majority of patients with an indolent disease from unnecessary procedures.

Evaluation of serum thyroid-stimulating hormone as indicator for fine-needle aspiration in patients with thyroid nodules

BACKGROUND

Recently, it has been reported that the risk of thyroid malignancy increases with increasing concentrations of serum thyroid-stimulating hormone (TSH). The purpose of this study was to determine whether or not serum TSH can be a predictor for thyroid malignancy when considering the relevant ultrasound features and clinical risk factors.

METHODS

This retrospective study included 1200 euthyroid patients with 1269 thyroid nodules who underwent ultrasound-guided fine-needle aspiration (FNA) biopsy between January and June 2009. Serum TSH, ultrasound feature, and clinical parameters were compared according to final diagnosis. Subgroup analyses were performed according to nodule size.

RESULTS

Serum TSH did not show a positive association with malignancy for all nodules and the micronodule subgroup in multivariate analysis, although they showed significant association with thyroid malignancy for the macronodule subgroup. For all nodules and the 2 subgroups, suspicious ultrasound features and younger age were significantly associated with malignancy in univariate and multivariate analyses.

CONCLUSION

Our study suggests that TSH alone is not as useful as ultrasound features in deciding whether or not to perform FNA in patients with micronodules.

Exercise is associated with better quality of life in patients on TSH-suppressive therapy with levothyroxine for differentiated thyroid carcinoma

Objective : To evaluate if a supervised exercise training program improves the quality of life (QoL) of differentiated thyroid carcinoma (DTC) patients on TSH-suppressive therapy with levothyroxine (L-T4).Subjects and methods : Initially, a cross-sectional study was performed to compare the QoL and the health-related quality of life (HRQoL) between subclinical hyperthyroidism (SCH) patients (n = 33) and euthyroid subjects (EU; n = 49). In the prospective phase of the study, SCH patients were randomized in a non-blinded fashion to either participate (SCH-Tr = trained patients; n = 16) or not (SCH-Sed = untrained patients; n = 17) in a supervised exercise training program. The exercise program consisted of 60 minutes of aerobic and stretching exercises, twice a week, during twelve weeks. The QoL was assessed by the application of the WHOQOL-Bref, and the SF-36 was used to assess the HRQoL.Results : SCH patients had statistically lower scores than EU on the “physical” domain of WHOQOL-Bref, besides “physical function”, “role-physical”, “bodily pain”, “general health”, “vitality”, “role-emotional”, and “mental-health” domains of SF-36. After three months, SCH-Tr patients showed improvement in the “physical” and “psychological” domains of WHOQOL-Bref (p < 0.05), and in the “physical function”, “role-physical”, “bodily pain”, “vitality” and “mental health” domains of SF-36.Conclusion : Patients on TSH-suppressive therapy with L-T4 for DTC had impaired QoL and HRQoL compared to EU, but it was improved after 3-months of an exercise training program. Exercise seems to play an important role in the follow-up of DTC patients, since it seems to minimize the adverse effects of the treatment on QoL and HRQoL. Arq Bras Endocrinol Metab. 2014;58(3):274-81

Relationship between VEGF protein expression and lymph node metastasis in papillary thyroid carcinoma among Asians: a meta-analysis

We carried out the current meta-analysis of relevant cohort studies in an attempt to investigate the relationships between vascular endothelial growth factor (VEGF) protein expression and lymph node (LN) metastasis in papillary thyroid carcinoma (PTC) among Asians. A range of electronic databases were searched, including Web of Science (1945∼2013), the Cochrane Library Database (Issue 12, 2013), MEDLINE (1966∼2013), EMBASE (1980∼2013), CINAHL (1982∼2013), and Chinese Biomedical Database (CBM) (1982~2013) with cross-referencing without language restrictions. Meta-analysis was conducted using the STATA 12.0 software. Crude odds ratio (OR) with their 95 % confidence interval (95 %CI) was calculated. Twelve clinical cohort studies with a total of 1,045 PTC patients were included in our meta-analysis, The results of our meta-analysis revealed that patients with VEGF-positive tumors had a 3.02-fold higher risk of LN metastasis than that of patients with VEGF-negative tumors (OR=3.02, 95 %CI=2.05~4.43, P<0.001). Furthermore, subgroup analysis by country suggested that VEGF-positive expression was associated with an increased risk of LN metastasis in PTC patients among Chinese populations (OR=3.33, 95 %CI=2.30~4.83, P<0.001), but not among Korean, Turkish, and Japanese populations (all P>0.05). Our findings support the view that VEGF protein expression may be correlated with LN metastasis in PTC patients, especially among Chinese populations.

Access, excess, and overdiagnosis: the case for thyroid cancer

The incidence of thyroid cancer in women is increasing at an epidemic rate. Numerous studies have proposed that the cause is increasing detection due to availability and use of medical diagnostic ultrasound. Our objective was to compare rates of diagnosis across different health-care regions to rates of diagnostic tests and to features of both health and access of the regional populations. This is a population-based retrospective ecological observational study of 12,959 patients with thyroid cancer between January 1, 2000 and December 31, 2008 in Ontario Canada based on the health-care utilization regions (Local Health Integration Networks) of the province of Ontario Canada. We found that some regions of Ontario had four times the rates of diagnosis of thyroid cancer compared to other regions. The regions with the highest use of discretionary medical tests (pelvic ultrasound, abdominal ultrasound, neck ultrasound, echocardiogram, resting electrocardiogram, cardiac nuclear perfusion tests, and bone scan), highest population density, and better education had the highest rates of thyroid cancer diagnoses. Differences in the rates of the ordering of discretionary diagnostic medical tests, such as diagnostic ultrasound, in different geographic regions of Ontario lead to differences in the rates of diagnosis of thyroid cancer.

Immune response in thyroid cancer: widening the boundaries

The association between thyroid cancer and thyroid inflammation has been repeatedly reported and highly debated in the literature. In fact, both molecular and epidemiological data suggest that these diseases are closely related and this association reinforces that the immune system is important for thyroid cancer progression. Innate immunity is the first line of defensive response. Unlike innate immune responses, adaptive responses are highly specific to the particular antigen that induced them. Both branches of the immune system may interact in antitumor immune response. Major effector cells of the immune system that directly target thyroid cancer cells include dendritic cells, macrophages, polymorphonuclear leukocytes, mast cells, and lymphocytes. A mixture of immune cells may infiltrate thyroid cancer microenvironment and the balance of protumor and antitumor activity of these cells may be associated with prognosis. Herein, we describe some evidences that immune response may be important for thyroid cancer progression and may help us identify more aggressive tumors, sparing the vast majority of patients from costly unnecessary invasive procedures. The future trend in thyroid cancer is an individualized therapy.

Changing patterns in thyroid cancer incidence and mortality in the Slovak Republic by histological type and age

BACKGROUND

Thyroid cancer (TC) is the most common malignant disease of the endocrine system; however, in the Slovak Republic (SR), time trends of incidence and mortality according to histological type and age of patients have never been reported.

MATERIALS AND METHODS

Long-term (1968-2007) trends from the National Cancer Registry data of overall, histology and age-specific incidence and mortality in the SR have been calculated using join-point regression and other descriptive characteristics.

RESULTS

Age-standardized overall incidence rates increased significantly in females by an estimated annual percentage change (APC) of 3.6 %, and in males by 2.2 %. Overall mortality decreased by APC -2.1 % in females and -0.9 % in males. The mean ages of female and male TC patients at the time of diagnosis significantly decreased; ages at the time of death significantly increased. The incidence of papillary carcinoma rose significantly in females by 8.9 %, compared with 6.1 % in males; follicular carcinoma in males and females was stable. Medullary carcinoma was stable in females; in males, it rose by 5.2 %. Poorly differentiated TC was stable in females; undifferentiated/anaplastic carcinomas decreased in both sexes.

CONCLUSIONS

The incidence of TC, especially of selected histological types, is dramatically rising in the SR in both genders, while mortality is decreasing. Patients diagnosed in recent years are younger and died at a greater age than those reported in older national data. These trends seem to be affected by more intensive diagnosis in the most recent years.

Genetic alterations in thyroid tumors from patients irradiated in childhood for tinea capitis treatment

OBJECTIVE

Exposure to ionizing radiation at young age is the strongest risk factor for the occurrence of papillary thyroid carcinoma (PTC). RET/PTC rearrangements are the most frequent genetic alterations associated with radiation-induced PTC, whereas BRAF and RAS mutations and PAX8-PPARG rearrangement have been associated with sporadic PTC. We decided to search for such genetic alterations in PTCs of patients subjected in childhood to scalp irradiation.

DESIGN

We studied 67 thyroid tumors from 49 individuals irradiated in childhood for tinea capitis scalp epilation: 36 malignant (12 cases of conventional PTC (cPTC), two cPTC metastases, 20 cases of follicular variant PTC (FVPTC), one oncocytic variant of PTC and one follicular carcinoma) and 31 follicular thyroid adenomas.

METHODS

The lesions were screened for the BRAF(V600E) and NRAS mutations and for RET/PTC and PAX8-PPARG rearrangements.

RESULTS

BRAF(V600E) mutation was detected in seven of 14 (50%) cPTC and two of 20 FVPTC (10%) (P=0.019). NRAS mutation was present in one case of FVPTC (5%). RET/PTC1 rearrangement was found, by RT-PCR, in one of 17 cases (5.9%) and by fluorescence in situ hybridization in two of six cases (33%). PAX8-PPARG rearrangement was not detected in any carcinoma. None of the follicular adenomas presented any of the aforementioned genetic alterations.

CONCLUSIONS

The prevalence of BRAF(V600E) mutation in our series is the highest reported in series of PTCs arising in radiation-exposed individuals. The prevalence of RET/PTC1 rearrangement fits with the values recently described in a similar setting.

Recent trends in the incidence, geographical distribution, and survival from thyroid cancer in Wales, 1985-2010

BACKGROUND

Previous studies of thyroid cancer incidence in Wales have given varying results with suggestions of an excess of cases in geographic areas that were previously exposed to the radioactive fallout from the 1986 Chernobyl nuclear reactor incident. Our objective in this study was to provide an up-to-date comprehensive analysis of time trends in the incidence, geographical distribution, and survival from thyroid cancer in Wales.

METHODS

We identified thyroid cancer cases, registered from 1985 through 2010 in the Welsh Cancer Intelligence and Surveillance Unit (WCISU). Age standardized rates were determined from the European standard population. A Poisson regression model was fitted to assess temporal trends and rate ratios (RRs) and confidence intervals (CIs) were determined and compared across consecutive time periods: 1985-1997 and 1998-2010. Standardized incidence ratios were calculated for each of the 22 local authority areas. Relative survival and Kaplan-Meier curves were computed to analyze all cause and thyroid cancer-specific survival.

RESULTS

A total of 1747 thyroid cancer cases were registered from 1985 to 2010. Age standardized incidence rates were 2.8 and 1.2 per 100,000 population per year for females and males respectively. Incidence rates increased with time (RR 1.3 [CI 1.2-1.5], p < 0.001; 1998-2010 vs. 1985-1997). The incidence of papillary cancer increased progressively over the study period (RR 2.22 [CI 1.91-2.57], p < 0.001; 1998-2010 vs. 1985-1997), while rates for other (nonpapillary) histological subtypes remained static (RR 0.95 [CI 0.84-1.08], p = 0.45; 1998-2010 vs. 1985-1997). We identified two geographical areas of increased incidence, but the spatial distribution of cases was inconsistent with exposure to radioactive fallout. Five-year relative survival from all-cause mortality improved from 74.2 [CI 66.8-80.1] in 1985-1989 to 82.6 [CI 77.1-86.9] in 2000-2004, but remained poor for patients over the age of 65 years (p < 0.001, > 65 years vs. 15-64 years) and patients with anaplastic thyroid cancer (p < 0.001; anaplastic vs. other histological varieties).

CONCLUSIONS

The incidence of thyroid cancer has increased in Wales, predominantly due to an increase in papillary cancers. The current geographical distribution of cases does not support a radiation effect in the region. Survival has remained poor for patients over the age of 65 years and those with anaplastic carcinoma.

Regulatory T cells and plasmacytoid dendritic cells contribute to the immune escape of papillary thyroid cancer coexisting with multinodular non-toxic goiter

Immunosuppressive lymphocytes, such as regulatory T cells (Tregs) and plasmacytoid dendritic cells (pDCs), play crucial roles in tumor escape. To investigate the roles of Tregs and pDCs in papillary thyroid cancer (PTC) plus multinodular non-toxic goiter (MNG), thyroid tissue and blood samples from 30 patients with PTC plus MNG and 30 MNG alone were analyzed for CD4(+) T cell, CD8(+) T cell, FoxP3(+) Treg, ICOS(+)FoxP3(+) Treg, and pDC numbers by immunohistochemistry (IHC), immunofluorescence, and flow cytometry. Plasma concentration of the cytokines interleukin 10 (IL-10) and transforming growth factor β (TGF-β) were measured by enzyme-linked immunosorbent assay as well. Both in thyroid tissue and peripheral blood, the numbers of Foxp3(+) Treg were significantly higher in patients with PTC plus MNG compared to patients with MNG alone; and as a prognostic marker, ICOS(+)Foxp3(+) Tregs represent a stronger predictor of disease progression than the total numbers of Foxp3(+) Tregs. Furthermore, a positive correlation between pDC and ICOS(+)Foxp3(+) Treg numbers in tissue of patients with PTC plus MNG was observed, suggesting that PTC-derived pDCs may induce the differentiation of naive CD4(+) T cells into ICOS(+)Foxp3(+)Tregs. This may be one of the mechanisms underlying tumor escape in PTC plus MNG patients. Our results suggest that Tregs and pDCs together contribute to the tumor escape in patients with PTC plus MNG.

Thyroid cancer cell resistance to gefitinib depends on the constitutive oncogenic activation of the ERK pathway

CONTEXT

Poorly differentiated thyroid carcinomas are refractory to common anticancer therapies, and novel inhibitors are being tested in these deadly malignancies. The epidermal growth factor receptor (EGFR) tyrosine kinase represents an attractive target for treatment because it is up-regulated in thyroid cancer and plays a role in cancer progression. However, EGFR inhibitors have provided poor results in thyroid carcinomas.

OBJECTIVE

We evaluated the possible mechanism underlying the resistance of thyroid cancer cells to EGFR inhibitors.

DESIGN

We tested the effect of the EGFR tyrosine kinase inhibitor gefitinib in a panel of thyroid cancer cell lines.

RESULTS

We found that in most of the cell lines, although gefitinib inhibited EGFR phosphorylation, it was poorly effective in reducing cell viability. gefitinib, however, was able to inhibit epidermal growth factor-induced cell migration and matrix invasion. In most thyroid cancer cell lines, gefitinib significantly inhibited Akt phosphorylation by inhibiting EGFR activation, but it had limited or no effect on ERK phosphorylation. The poor cell response to gefitinib was associated with genetic alterations, leading to constitutive activation of the ERK pathway, including BRAF(V600E) and HRAS(G12A/Q61R) mutations and RET/PTC1 rearrangement. When BRAF(V600E)-positive thyroid cancer cells were incubated with the specific BRAF inhibitor PLX4032, sensitivity to gefitinib was restored. Similar results were obtained with rat sarcoma and RET/papillary thyroid cancer inhibitors.

CONCLUSIONS

These results indicate that thyroid cancer resistance to gefitinib is due to the constitutive activation of the mitogenic pathway by either signals downstream of EGFR or other tyrosine kinase receptors. This resistance can be overcome by the combined use of selective inhibitors.

Laparoscopic partial nephrectomy of thyroid cancer metastasis: case report and review of the literature

Background

Follicular cell thyroid carcinoma is a quite aggressive form of thyroid cancer. About 10% of follicular thyroid carcinoma shows multiple metastases: lung and bone are the most common sites of metastasis. Renal involvement from thyroid primary cancer is very rare with incidence of 4.5%–5.9%.

Purpose

We report the first laparoscopic conservative treatment of renal metastasis from thyroid cancer. This is a new and useful approach in order to delay malignant disease progression and to reduce the surgical discomfort of the patient.

Patients and methods

We present the case of a 67-year-old woman, undergoing total thyroidectomy for follicular thyroid cancer with bone and lung metastasis. During adjuvant radiometabolic treatment, renal metastasis was diagnosed. Renal metastasis showed high metabolic activity, reducing the effectiveness of radioiodine therapy for secondary lesions. For this reason, we performed a laparoscopic simple enucleation of the single renal metastasis using extraperitoneal access and a clampless procedure.

Results

The excision of the renal lesion improved the effectiveness of adjuvant radioiodine therapy: two months after surgery, the patient underwent adjuvant radiometabolic treatment with iodine-131 (150 mCi) and the following whole body scan showed only a small uptaking area at the level of the vertebral metastasis. The lung micrometastases were not detectable. At 36 months follow-up, malignant disease was clinically stable and well controlled.

Conclusion

Minimally invasive renal surgery with preservation of renal function and rapid recovery contributed to the success of radioiodine therapy and delayed the progression of the disease.

Fine needle aspiration cytology of nodular thyroid lesions: a 2-year experience of the Bethesda system for reporting thyroid cytopathology in a large regional and a university hospital, with histological correlation

OBJECTIVE

Thyroid fine needle aspiration (FNA) contributes to the appropriate management of nodular thyroid lesions. The introduced categories in the Bethesda system for reporting thyroid cytopathology (TBSRTC) are associated with an implied cancer risk, providing a clinical management guideline. This study aims to evaluate the reproducibility of this implied risk and to compare the results from two different cytopathology departments.

METHODS

Five hundred histologically confirmed FNAs, studied since the introduction of TBSRTC, were obtained from 4208 and 3587 FNAs performed in a large regional hospital in Herakleion, Crete (group A) and a university hospital in Athens (group B), respectively. Reports were issued according to TBSRTC. Aspirates were prepared with ThinPrep(®) and evaluated by two experienced cytopathologists. The reproducibility and accuracy were evaluated.

RESULTS

The proportion test for suspicious for malignancy (SFM) and malignant (M) cytology reports (P < 0.0001), and the number of malignancies on histology (P < 0.0001), were significantly higher in group A than in group B, consistent with a higher incidence of thyroid carcinomas in southern Greece. Although the malignancy rates were higher in group A than in group B for all categories, except M (A, 99.3%; B, 100%), the difference was only significant for benign aspirates (P = 0.0303). Malignancy rates for all categories in group A were above the TBSRTC recommended range, but were consistent with an increased prevalence of malignancy in that centre, differences in reporting practice and the variable ranges reported in the literature. There was lower sensitivity (P = 0.019) and overall accuracy (P = 0.003) in group A relative to group B, but no difference in specificity.

CONCLUSIONS

TBSRTC provides valuable information for the appropriate management of nodular thyroid lesions, both in a university and a large regional hospital.

Hashimoto's thyroiditis: similar and dissimilar characteristics in neighboring areas. Possible implications for the epidemiology of thyroid cancer

CONTEXT

Medical centers worldwide report an increased frequency of Hashimoto's thyroiditis (HT) and thyroid cancer (TC), two environmentally influenced diseases. In Sicily, data on HT are available for the province of Messina (1975-2005); data on TC are available for the whole island (2002-2004), with the volcanic province of Catania having the highest incidence.

OBJECTIVE

To replicate in Catania, on comparable years, the HT data of Messina. DESIGN METHODS SETTING: Review of the clinical records of patients in years 1995-2005 to compare presentation and yearly changes of HT. During 1995-2005, records were computer stored in the Endocrine Divisions of the University Hospitals of Catania and Messina, two tertiary referral centers.

RESULTS

Catania is outnumbered by Messina (742 vs. 3,409 HT patients). Similar were the linear increase in the yearly number of HT patients, rates of thyroid dysfunctions though with different proportions of subclinical and overt hypothyroidism, and rates of positiveness for TgAb or TPOAb. Different were age and its yearly trend; gender distribution and rates of the sonography variants, though yearly trends were similar.

CONCLUSION

The HT epidemics is smaller in Catania, with changes in presentation overlapping partially those in Messina. Whatever environmental factors might be involved, they (and/or their intensity) were not necessarily the same in these provinces. Intriguingly, the expected number of TC in HT patients with thyroid nodules in Catania is congruent with that of the general population of this province, but it is far less than in the Messina province. Thus, TC and HT incidences could be influenced by distinct environmental factors.

Epidemiology of thyroid cancer in an area of epidemic thyroid goiter

The aim of this study was to analyze and describe the epidemiological characteristics and trends of thyroid cancer in the province of Sassari (Sardinia, Italy), an area with epidemic thyroid goiter, in the period 1992–2010. Data were obtained from the local tumor registry which makes part of a wider registry web, coordinated today by the Italian Association for Tumor Registries. An increasing trend in the incidence of thyroid cancer in the province of Sassari was evidenced. This trend seems to follow the general worldwide trend and does not seem to be related to the high incidence of thyroid goiter in the area. The frequencies of the different histological subtypes were similar to those reported in numerous national and international reports. Women are affected earlier than men and, therefore, suffer greater professional, economic, and social impacts. Overall mortality is low and a relative 5-year survival is excellent, especially in comparison to other malignancies.

Incidence of thyroid cancer surrounding Three Mile Island nuclear facility: the 30-year follow-up

OBJECTIVES/HYPOTHESIS

Original data reported a potential increased incidence of thyroid cancer surrounding the Three Mile Island (TMI) nuclear facility. A causal link to the accident, however, was indeterminate. Our objective was to determine if data 30 years later will change original conclusions, explore thyroid cancer incidence rates near nuclear power plants, and better understand effects of chronic low level radiation.

STUDY DESIGN

Retrospective cross-sectional study.

METHODS

Retrospective data for specific Pennsylvania counties were provided by the Pennsylvania Cancer Registry Dataset for thyroid cancer using the Epidemiological Query and Mapping System search engine. Our study examines thyroid cancer incidence from 1985 through 2009 analyzed by year, county, and age.

RESULTS

Thirty years after the TMI accident, an increased incidence of thyroid cancer is seen in counties south of TMI and in high-risk age groups. The average incidence rates from 1990 through 2009 were greater than expected in York, Lancaster, Adams, and Chester Counties.

CONCLUSIONS

Thyroid cancer incidence since the TMI accident was greater than expected in the counties analyzed when compared to local and national population growth. This supports a link to chronic low level radiation exposure and thyroid cancer development. Despite these findings, a direct correlation to the accident remains uncertain as incidence rates may coincide with other factors, and original data were limited.

Cigarette smoking, alcohol intake, and thyroid cancer risk: a pooled analysis of five prospective studies in the United States

OBJECTIVE

We examined the associations between cigarette smoking, alcohol intake, and thyroid cancer risk in a pooled analysis of five prospective studies.

METHODS

Data from five prospective U.S. studies were standardized and then combined into one aggregate dataset (384,433 men and 361,664 women). Pooled hazard ratios (HR) and 95 % confidence intervals (CI) for thyroid cancer were estimated from mutually adjusted models of cigarette smoking and alcohol intake, which were additionally adjusted for age, sex, education, race, marital status, body mass index, and cohort.

RESULTS

Over follow-up, 1,003 incident thyroid cancer cases (335 men and 668 women) were identified. Compared to never smokers, current smoking was associated with reduced risk of thyroid cancer (HR = 0.68, 95 % CI 0.55-0.85); this association was slightly stronger among non-drinkers (HR = 0.46, 95 % CI 0.29-0.74). No reduction in risk was observed for former, compared to never, smokers. Greater smoking intensity, duration, and pack-years were associated with further reductions in risk among former and current smokers. Alcohol intake was also inversely associated with thyroid cancer risk (≥7 drinks/week versus 0, HR = 0.72, 95 % CI 0.58-0.90, p trend = 0.002). Inverse associations with smoking and alcohol were more pronounced for papillary versus follicular tumors.

CONCLUSION

The results of this pooled analysis suggest that both cigarette smoking and alcohol consumption are associated with reduced risks of papillary thyroid cancer and, possibly, follicular thyroid cancer.

Increasing incidence of thyroid cancer in Great Britain, 1976-2005: age-period-cohort analysis

Increases in the incidence of thyroid cancer have been previously reported. The purpose of the present study was to examine temporal trends in the incidence of primary thyroid cancer diagnosed in 0-49 year olds in parts of Great Britain during 1976-2005. Data on 4,337 cases of thyroid cancer were obtained from regional cancer registries. Age-standardized incidence rates (ASRs) were calculated. Negative binomial regression was used to examine effects of age, sex, drift (linear trend), non-linear period and non-linear cohort. The best fitting negative binomial regression model included age (P < 0.001), sex (P < 0.001) and drift (P < 0.001). Non-linear period (P = 0.648) and non-linear cohort (P = 0.788) were not statistically significant. For males aged 0-14, the ASR increased from 0.2 per million persons per year in 1976-1986 to 0.6 in 1997-2005. For males aged 15-29 and 30-49 the ASRs increased from 1.9 to 3.3 and from 7.4 to 12.7, respectively. For females aged 0-14, the corresponding ASR increased from 0.3 to 0.5. For females aged 15-29 and 30-49 the ASRs increased from 6.9 to 12.4 and from 21.2 to 42.3, respectively. For all age groups, there has been a linear increase in incidence of thyroid cancer, which has led to a doubling of the number of cases diagnosed over a twenty year span. The reasons for this increase are not well understood, but it is consistent with findings from other countries.

The role of fragile sites in sporadic papillary thyroid carcinoma

The incidence of thyroid cancer is increasing, especially papillary thyroid carcinoma (PTC), making it currently the fastest-growing cancer among women. Reasons for this increase remain unclear, but several risk factors including radiation exposure and improved detection techniques have been suggested. Recently, the induction of chromosomal fragile site breakage was found to result in the formation of RET/PTC1 rearrangements, a common cause of PTC. Chromosomal fragile sites are regions of the genome with a high susceptibility to forming DNA breaks and are often associated with cancer. Exposure to a variety of external agents can induce fragile site breakage, which may account for some of the observed increase in PTC. This paper discusses the role of fragile site breakage in PTC development, external fragile site-inducing agents that may be potential risk factors for PTC, and how these factors are especially targeting women.

RET TKI: potential role in thyroid cancers

The increasing incidence of thyroid cancer is associated with a higher number of advanced disease characterized by the loss of cancer differentiation and metastatic spread. The knowledge of the molecular pathways involved in the pathogenesis of thyroid cancer has made possible the development of new therapeutic drugs able to blockade the oncogenic kinases (RET/PTC) or signaling kinases (vascular endothelial growth factor receptor [VEGFR]) involved in cellular growth and proliferation. Some clinical trials have been conducted showing the ability of targeted therapies able to inhibit RET(sorafenib, imatinib, vandetanib) in stabilizing the course of the disease. The aim of the introduction of these targeted therapies is to extend life duration assuring a good quality of life; however, further studies are needed to reach these goals.

Thyroid cancer in Denmark 1943-2008, before and after iodine supplementation

Thyroid cancer incidence has increased worldwide during the previous decades. In this nationwide study, we aimed to identify the overall incidence of thyroid cancer in Denmark during 66 years (1943-2008) and incidences of the four main histological types of thyroid cancer from 1978 to 2008. Data were obtained from the nationwide Danish Cancer Registry, and we focused especially on the period after implementation of compulsory iodine supplementation, which was established on a national level in 2000. We calculated age-standardized incidence rates per 100,000 person-years, and age-period-cohort models were fitted to describe trends in incidence. To quantify trends in incidence over time, log-linear Poisson models were used to estimate annual percentage change. From 1943 to 2008, 1,947 men (29%) and 4,682 women (71%) were diagnosed with thyroid cancer. The age-standardized incidence increased in both sexes; in men from 0.41 to 1.57 per 100,000 and from 0.90 to 4.11 per 100,000 in women, corresponding to a significant average annual percentage change of 1.7 and 1.8%, respectively. The incidence increased with younger birth cohorts. The rise was almost exclusively caused by papillary carcinomas, and it was particularly present during the last decades of the study period. It cannot be ruled out that iodine supplementation may play a role for the risk of thyroid cancer, but as the strongest increase in incidence began in the years before the implementation, it is likely that improvement in diagnostic modalities increased diagnostic activity, and/or new unknown risk factors are also important contributors to the increase.

Are there predictors of malignancy in patients with multinodular goiter?

BACKGROUND

Multinodular goiters (MNG) have recently been shown to have an incidence of cancer that approaches that of solitary thyroid nodule. However, fine needle aspiration (FNA) of a MNG is limited due to the presence of multiple nodules. Therefore we sought to identify risk factors for malignancy in patients with MNG.

METHODS

A total of 1791 consecutive patients underwent thyroidectomy at a single academic institution between May 1994 and December 2009. Of these, 838 patients had a MNG, which we defined as ≥ 2 nodules on preoperative ultrasound. The medical records of these patients were reviewed and analyzed.

RESULTS

A final pathologic diagnosis of malignancy was found in 260 of 838 (31%) of MNG patients. Of the 260 patients with malignancy, 113 (44%) had a focus of cancer <1 cm. Of the patients with malignancy on final pathology, preoperative FNA detected only 46% (n = 120). Of the 140 cancers not recognized preoperatively, 61 (44%) were >1 cm in size. On univariate analysis risk factors for malignancy were younger age and male gender. Patients with malignant nodules also had smaller nodules, smaller thyroids, and fewer nodules than those patients with benign findings on pathology. On multivariate analysis all predictors remained independently associated with malignancy with the exception of thyroid weight.

CONCLUSION

Risk factors for malignancy in a MNG included male gender, younger age, fewer nodules, and smaller nodule size. The low predictive value of FNA in our population suggests there needs to be better ways to predict malignancy in patients with MNG. Therefore, these clinical risk factors should be considered when consulting patients with MNG in regards to their risk of malignancy.

Interaction between ionizing radiation and estrogen: what we are missing?

Following complexity as a new approach in science of 21st century biomonitoring of biological effects caused by ionizing radiation received an option of a new dimension. Insight in biological response of mammals to ionizing radiation exposure by integration of genome, non-genome and distant organ bystander effects will significantly change evaluation of health risk and preventive measures. Impact of estrogen on carcinogenesis caused by occupational or accidental exposure to ionizing radiation additionally enables biodosimetry to recognize vulnerable subpopulations according to gender and age. Estrogen, as a potent molecule involved in number of biological pathways during development and adulthood, shows close interaction with pathological processes launched by overexposure to ionizing radiation which should be included in future research and radiation protection.

Clinical and pathological implications of concurrent autoimmune thyroid disorders and papillary thyroid cancer

Cooccurrences of chronic lymphocytic thyroiditis (CLT) and thyroid cancer (DTC) have been repeatedly reported. Both CLT and DTC, mainly papillary thyroid carcinoma (PTC), share some epidemiological and molecular features. In fact, thyroid lymphocytic inflammatory reaction has been observed in association with PTC at variable frequency, although the precise relationship between the two diseases is still debated. It also remains a matter of debate whether the association with a CLT or even an autoimmune disorder could influence the prognosis of PTC. A better understanding about clinical implications of autoimmunity in concurrent thyroid cancer could raise new insights of thyroid cancer immunotherapy. In addition, elucidating the molecular mechanisms involved in autoimmune disease and concurrent cancer allowed us to identify new therapeutic strategies against thyroid cancer. The objective of this article was to review recent literature on the association of these disorders and its potential significance.

Downregulation of uPAR inhibits migration, invasion, proliferation, FAK/PI3K/Akt signaling and induces senescence in papillary thyroid carcinoma cells

Papillary thyroid carcinoma (PTC) is the most common endocrine and thyroid malignancy.  The urokinase plasminogen activator receptor (uPAR) plays an important role in cancer pathogenesis, including breakdown of the extracellular matrix, invasion, and metastasis.  Additionally, there is increasing evidence that uPAR also promotes tumorigenesis via the modulation of multiple signaling pathways.  BRAFV600E, the most common initial genetic mutation in PTC, leads to ERK1/2 hyperphosphorylation, which has been shown in numerous cancers to induce uPAR.  Treatment of the BRAFV600E-positive PTC cell line, BCPAP, with the MEK/ERK inhibitor U0126 reduced uPAR RNA levels by 90%.  siRNA-mediated down-regulation of uPAR in BCPAP cells resulted in greatly decreased activity in the focal adhesion kinase (FAK)/phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway.  This phenomenon was concurrent with drastically reduced proliferation rates and decreased clonigenic survival, as well as demonstrated senescence-associated nuclear morphology and induction of b-galactosidase activity. uPAR-knockdown BCPAP cells also displayed greatly reduced migration and invasion rates, as well as a complete loss of the cells' ability to augment their invasiveness following plasminogen supplementation. Taken together, these data provide new evidence of a novel role for uPAR induction (as a consequence of constitutive ERK1/2 activation) as a central component in PTC pathogenesis, and highlight the potential of uPAR as a therapeutic target.