Increased risk for nonmedullary thyroid cancer in the first degree relatives of prevalent cases of nonmedullary thyroid cancer: a hospital-based study

TIROSEC: Molecular, Clinical and Histopathological Profile of Papillary Thyroid Carcinoma in a Colombian Cohort

INTRODUCTION

In Colombia, thyroid cancer ranks among the highest incidences, yet our population lacks studies on its molecular profile. This study aims to characterize clinical, histopathologic and molecular data in a Colombian cohort with papillary thyroid carcinoma (PTC).

METHODS

A retrospective review of clinical history, clinicopathologic characteristics, treatment and 5-10-year follow-up for all patients was done. DNA and RNA were extracted from formalin-fixed paraffin-embedded (FFPE) tissue using the Quick-DNA & RNA FFPE Min iPrep kit (Zymo Research). Next-generation sequencing (NGS) analysis was performed with SOPHiA Solid Tumor Solutions kit (SOPHiA GENETICS). Tumor mutation genomic analysis used SOPHiA DDM™ platform, with descriptive analysis reporting frequencies, means and associations via chi-square analysis.

RESULTS

Among 231 sequenced patients, mean age at diagnosis was 46 (± 12.35) years, with higher frequency in women (81.82%). Two cases were reclassified as non-invasive follicular thyroid neoplasm (NIFT-P); an NRAS mutation was found in one of them. Predominant histologic subtype was classic PTC (57.64%) followed by tall cell (28.82%). Of the 229 sequenced carcinomas, mutations were identified in 186 cases, including BRAF, IDH1, RAS and PIK3CA. Notable copy number variations (CNVs) were PDGFRA, CDK4 and KIT, with RET being the most frequent gene fusion, including CCDC6-RET in two classic subtype cases.

CONCLUSION

This is the first study in Colombia (TIROSEC) to our knowledge that integrates molecular and histopathologic profiles enriching our local comprehension and knowledge of PTC. The identification of target mutations such as BRAF, RET and NTRK fusions holds the potential to guide targeted therapies for tumor recurrence and predict aggressive behavior.

Clinical relevance and outcome of familial papillary thyroid cancer: a single institution study of 626 familial cases

Background

Whether familial thyroid cancer is more aggressive than sporadic thyroid cancer remains controversial. Additionally, whether the number of affected family members affects the prognosis is unknown. This study focused mainly on the comparison of the clinicopathological characteristics and prognoses between papillary thyroid cancer (PTC) patients with and without family history.

Methods

A total of 626 familial papillary thyroid cancer (FPTC) and 1252 sporadic papillary thyroid cancer (SPTC) patients were included in our study. The clinical information associated with FPTC and SPTC was recorded and analyzed by univariate analysis.

Results

Patients in the FPTC group had a higher rate of multifocality (p=0.001), bilaterality (p=0.000), extrathyroidal invasion (p=0.000), distant metastasis (p=0.012), lymph node metastasis (p=0.000), recurrence (p=0.000), a larger tumor size (p=0.000) and more malignant lymph nodes involved (central: p=0.000; lateral: p=0.000). In addition, our subgroup analysis showed no significant difference (p>0.05) between patients with only one affected family member and those with two of more group in all clinicopathological characteristics. In papillary thyroid microcarcinoma (PTMC) subgroup analysis, we found that FPTMC patients harbored significantly larger tumors (p=0.000), higher rates of multifocality (p=0.014), bilaterality (p=0.000), distant metastasis (p=0.038), lymph node metastasis (p=0.003), greater numbers of malignant lymph nodes (central: p=0.002; lateral: p=0.044), higher rates of I-131 treatment (p=0.000) and recurrence (p=0.000) than SPTMC patients.

Conclusion

Our results indicated that PTC and PTMC patients with a positive family history had more aggressive clinicopathological behaviors, suggesting that more vigilant screening and management for FPTC may be helpful.

Differentiated thyroid carcinoma: An update

Differentiated thyroid carcinoma (DTC) is the most common endocrine cancer. Particularly the incidence of small clinically indolent tumors has been increasing significantly during the last decades because of increased diagnostic scrutiny, while the DTC-related mortality remained unchanged. In light of the increased awareness of the significant risk of detecting clinically indolent tumors and the potential harm and burden associated with overly diagnosis and the treatment, the approach towards management of DTC recently underwent a critical appraisal. The focus lays on reducing the unnecessary burden for patients with very low risk DTC and the correct identification of those who require treatment that is more intensive and/or follow-up. Management of DTC includes a range of different modalities, making multidisciplinary collaboration expedient. In this review, we elaborate on the recent developments in diagnosis, staging and management of DTC with specific focus on the more individualized risk assessment-based approach.

Metformin and thyroid carcinoma incidence and prognosis: A systematic review and meta-analysis

Metformin has been suggested to reduce thyroid cancer incidence and to improve thyroid cancer prognosis. We aimed to evaluate the associations between metformin and thyroid cancer incidence and prognosis (metastasis/recurrence/progression-free survival). Cochrane Library, PubMed, ClinicalTrials.gov, and U.S. National Library of Medicine Clinical Trials were searched through the end of December 2021. Data were collected from original observational studies or clinical trials on the incidence or prognosis of thyroid carcinoma outcomes in type 2 diabetes mellitus (T2DM) patients with and without metformin use. Risk of bias in non-randomized studies of interventions (ROBINS-I) tool and Grading of Recommendations, and Assessment, Development and Evaluations (GRADE) approach were used to evaluate the risk of bias and quality of the body of evidence, respectively. In general, 4 studies were related to the thyroid cancer incidence, including 1,705,123 participants metformin users and non-users and yielding a total of 3,238 thyroid cancer events; 3 studies reported the prognosis of thyroid carcinoma based on a total of 4,972 individuals with primary thyroid carcinoma and comorbid type 2 diabetes, and the number of thyroid cancer prognosis cases ranged from 3 to 79. The overall risk of bias of the included studies ranged from moderate to serious. In the random-effects model, the summary relative risk (SRR) for thyroid cancer incidence was 0.743 (95% CI: 0.453–1.220; I2 = 88.7%, low certainty) comparing metformin users to non-users; and SRR for the prognosis of thyroid cancer was 0.504 (95% CI: 0.178–1.430; I2 = 57.5%, low certainty). Non-statistically significant negative associations between metformin use and incidence and prognosis of thyroid cancer were found in the current analysis, although the quantity and quality of the evidence were limited. Futher investigation is needed to evaluate the clinical benefits of metformin on thyroid cancer prevention and treatments.

Genetic susceptibility to hereditary non-medullary thyroid cancer

Non-medullary thyroid cancer (NMTC) is the most common type of thyroid cancer. With the increasing incidence of NMTC in recent years, the familial form of the disease has also become more common than previously reported, accounting for 5-15% of NMTC cases. Familial NMTC is further classified as non-syndromic and the less common syndromic FNMTC. Although syndromic NMTC has well-known genetic risk factors, the gene(s) responsible for the vast majority of non-syndromic FNMTC cases are yet to be identified. To date, several candidate genes have been identified as susceptibility genes in hereditary NMTC. This review summarizes genetic predisposition to non-medullary thyroid cancer and expands on the role of genetic variants in thyroid cancer tumorigenesis and the level of penetrance of NMTC-susceptibility genes.

Thyroid cancer in the Democratic Republic of the Congo: Frequency and risk factors

BACKGROUND

The prevalence of thyroid cancer is increasing steadily in most countries, partly due to better, earlier diagnosis. However, there is little data for developing countries, where the technical platform is often very limited, especially in Africa.

OBJECTIVES

To assess the frequency of thyroid cancer in the Democratic Republic of the Congo (DRC) and to analyze the epidemiological, clinical, and ultrasound risk factors.

MATERIAL AND METHODS

This is a multicenter cross-sectional study of 594 patients operated on for a thyroid mass from 2005 to 2019, in 35 centers in the DRC and for whom histopathological analyses were performed.

RESULTS

The frequency of thyroid cancers in our cohort was 20%, mostly in patients over the age of 40 (62% of patients). These cancers were mainly diagnosed at the clinical stage, due to the presence of palpable masses. Papillary cancer was the most common (67.2% of patients), followed by follicular cancer (28% of cases). We found a high prevalence of anaplastic cancer (7.6%). These frequencies are probably the consequence of the fact that histopathological analyses are not systematically performed in the DRC, but mostly on tissues that the thyroid surgeons suspect to be malignant. Age ≥60 years, the presence of adenopathies upon palpation or on ultrasound, the solid nature and hypoechogenicity of nodules, the presence of macronodules and calcifications were the factors independently associated with the diagnosis of cancer in the study population.

CONCLUSIONS

In this first study performed in the DRC, we have found that thyroid cancer is common. It is mainly detected at clinical stages, with patients over the age of 40 years and women being the most affected. The histopathology distribution differs from that in developed countries, with a lower prevalence of papillary cancer and a higher prevalence of the anaplastic type. In developing countries, it appears necessary to introduce the use of more precise diagnostic tools for thyroid cancer and also, to reinforce the improvement of known, controllable risk factors such as iodine deficiency.

Germ-line mutations in WDR77 predispose to familial papillary thyroid cancer

The inheritance of predisposition to nonsyndromic familial nonmedullary thyroid cancer (FNMTC) remains unclear. Here, we report six individuals with papillary thyroid cancer (PTC) in two unrelated nonsyndromic FNMTC families. Whole-exome sequencing revealed two germ-line loss-of-function variants occurring within a 28-bp fragment of WDR77, which encodes a core member of a transmethylase complex formed with the protein arginine methyltransferase PRMT5 that is responsible for histone H4 arginine 3 dimethylation (H4R3me2) in frogs and mammals. To date, the association of WDR77 with susceptibility to cancer in humans is unknown. A very rare heterozygous missense mutation (R198H) in WDR77 exon 6 was identified in one family of three affected siblings. A heterozygous splice-site mutation (c.619+1G > C) at the 5' end of intron 6 is present in three affected members from another family. The R198H variant impairs the interaction of WDR77 with PRMT5, and the splice-site mutation causes exon 6 skipping and results in a marked decrease in mutant messenger RNA, accompanied by obviously reduced H4R3me2 levels in mutation carriers. Knockdown of WDR77 results in increased growth of thyroid cancer cells. Whole-transcriptome analysis of WDR77 mutant patient-derived thyroid tissue showed changes in pathways enriched in the processes of cell cycle promotion and apoptosis inhibition. In summary, we report WDR77 mutations predisposing patients to nonsyndromic familial PTC and link germ-line WDR77 variants to human malignant disease.

Hereditary Endocrine Tumors and Associated Syndromes: A Narrative Review for Endocrinologists and Endocrine Surgeons

OBJECTIVE

Hereditary endocrine tumors (HET) were among the first group of tumors where predisposition syndromes were recognized. The utility of genetic awareness is having the capacity to treat at an earlier stage, screen for other manifestations and initiate family cascade testing. The aim of this narrative review is to describe the most common hereditary syndromes associated with frequently encountered endocrine tumors, with an emphasis on screening and surveillance.

METHODS

A MEDLINE search of articles for relevance to endocrine tumors and hereditary syndromes was performed.

RESULTS

The most common hereditary syndromes associated with frequently encountered endocrine tumors are described in terms of prevalence, genotype, phenotype, penetrance of malignancy, surgical management, screening and surveillance.

CONCLUSION

Medical practitioners involved in the care of patients with endocrine tumors, should have an index of suspicion for an underlying hereditary syndrome. Interdisciplinary care is integral to successful, long-term management of these patients and affected family members.

Familial Non-Medullary Thyroid Carcinoma in Pediatric Age: Our Surgical Experience

Background

The purpose of the article was to evaluate the existence of significant clinical, pathological and prognostic differences between familial and sporadic form of pediatric non-medullary thyroid carcinoma, in order to tailor the therapeutic strategy to be adopted for patients with family history.

Methods

We analyzed the records of 76 pediatric patients that underwent surgery for differentiated thyroid cancer from 2014 to 2019 at the Surgical Pathology Department of the University of Pisa, Italy. Among these, 20 (26,3%) had positive family history (familial non-medullary thyroid carcinoma—FNMTC group) while 56 (73.7%) were affected by sporadic forms (sporadic non-medullary thyroid carcinoma—SNMTC group).

Results

In our study, the correlation between the FNMTC and the SNMTC group showed no difference in terms of tumor features like multifocality, bilaterality, capsular/extracapsular invasion and the presence of vascular emboli. A statistical significance, on the other hand, was revealed by observation of clinical outcomes, such as distant metastasis (p = 0,022), persistence of disease (p = 0,054) and necessity of radioiodine sessions (p = 0,005).

Conclusions

These findings suggest that family history may have an independent role on the outcome, expressing its action through an intrinsic more aggressive biological behavior. Therefore, familial non-medullary thyroid carcinoma in children represents a nosological entity that requires an accurate pre-operative evaluation, an adequate surgical strategy and a careful follow up.

Diet as a possible influencing factor in thyroid cancer incidence: the point of view of the nutritionist

The incidence of differentiated thyroid cancer has increased in the last decades all over the world. Different environmental factors are possible perpetrators of this exponential growth. Nutritional factors are among the main environmental factors studied for thyroid cancer in recent years. This review aims to overview the main dietary factors involved in thyroid cancer risk, providing specific nutrition recommendations from the endocrinological Nutritionist point of view. Among the single food, fish and shellfish are the primary natural source of iodine, selenium and vitamin D in the human diet. These nutrients are essential for the synthesis of thyroid hormones; however, their consumption is not consistently related to thyroid cancer risk. The high intake of fruit and vegetables, probably due to their vitamin and antioxidant content, shows a weak inverse association with thyroid cancer risk. Alcohol, meat, or other food groups/nutrients showed no significant effect on thyroid cancer. In conclusion, to date, no definite association among dietary factors, specific dietary patterns, and thyroid cancer, and its clinical severity and aggressiveness have been found. However, it is essential to underline that in the future, prospective studies should be carried out to precisely evaluate the qualitative and quantitative intake of nutrients by patients to establish with more confidence a potential correlation between food intake and the occurrence and development of thyroid cancer.

Inherited Follicular Epithelial-Derived Thyroid Carcinomas: From Molecular Biology to Histological Correlates

Cancer derived from thyroid follicular epithelial cells is common; it represents the most common endocrine malignancy. The molecular features of sporadic tumors have been clarified in the past decade. However the incidence of familial disease has not been emphasized and is often overlooked in routine practice. A careful clinical documentation of family history or familial syndromes that can be associated with thyroid disease can help identify germline susceptibility-driven thyroid neoplasia. In this review, we summarize a large body of information about both syndromic and non-syndromic familial thyroid carcinomas. A significant number of patients with inherited non-medullary thyroid carcinomas manifest disease that appears to be sporadic disease even in some syndromic cases. The cytomorphology of the tumor(s), molecular immunohistochemistry, the findings in the non-tumorous thyroid parenchyma and other associated lesions may provide insight into the underlying syndromic disorder. However, the increasing evidence of familial predisposition to non-syndromic thyroid cancers is raising questions about the importance of genetics and epigenetics. What appears to be "sporadic" is becoming less often truly so and more often an opportunity to identify and understand novel genetic variants that underlie tumorigenesis. Pathologists must be aware of the unusual morphologic features that should prompt germline screening. Therefore, recognition of harbingers of specific germline susceptibility syndromes can assist in providing information to facilitate early detection to prevent aggressive disease.

Alteration of DNA mismatch repair capacity underlying the co-occurrence of non-small-cell lung cancer and nonmedullary thyroid cancer

Both non-small-cell lung cancer cases in never-smokers and nonmedullary thyroid cancer cases have been increasing in developed countries. Some studies have shown an excess of co-occurrence of non-small-cell lung cancer and nonmedullary thyroid cancer. We aimed to clarify the underlying genetic factors that contribute to the occurrence of these two malignancies. We performed germline exome sequencing in a cohort of 9 patients with the two malignancies. In terms of candidate genes, we performed target resequencing, immunohistochemistry, and microsatellite instability testing on another cohort. Two rare missense heterozygous variants in MSH6 were identified and verified by Sanger sequencing. One available tumour specimen showed heterogeneous MSH6 status in immunohistochemistry. Further exploration with different cohorts (a total of 8 patients with the two malignancies) demonstrated that 2 out of 8 patients had a germline missense or promotor variant of MLH1 and four out of 10 tumour specimens revealed heterogeneous immunohistochemistry staining in any of the four mismatch repair proteins: MLH1, PMS2, MSH2 and MSH6. Although our cohort showed a different disease profile than Lynch syndrome, this study suggests causal roles of impaired DNA mismatch repair capacity in non-small-cell lung cancer and nonmedullary thyroid cancer.

Should Total Thyroidectomy Be Recommended for Patients with Familial Non-medullary Thyroid Cancer?

BACKGROUND

It is unknown whether familial non-medullary thyroid cancer (FNMTC) has more aggressive clinical features and a worse prognosis than sporadic non-medullary thyroid cancer (SNMTC).

METHODS

We retrospectively reviewed 2894 patients with differentiated thyroid cancer who underwent primary thyroidectomy, identified 391 FNMTC cases, and compared the prevalence, surgical extension, and clinicopathologic features of FNMTC and SNMTC.

RESULTS

A family history of thyroid cancer was noted in 391 patients (13.5%), with 85% having two affected relatives and 15% with ≥3 affected relatives. A sibling was affected in 52.9% of cases, and in 47.1%, both parent and child were affected. There were no significant between-group differences in sex, age, tumor size, extrathyroidal extension, or central lymph node metastases. Significantly more patients with FNMTC exhibited multifocal disease (p = 0.020) or benign nodules (p = 0.015). Lateral neck lymph node metastases were noted in 6.6% (SNMTC) and 9.7% (FNMTC, p = 0.021) of patients. Multifocality and combined benign masses were more frequently observed in patients with FNMTC in multivariate analysis. In the FNMTC group, seven experienced disease recurrence, with no mortality noted during follow-up.

CONCLUSIONS

FNMTC is not more aggressive than SNMTC; however, FNMTC should be treated with total thyroidectomy because of the increased disease multifocality and the presence of benign nodules. Lateral neck lymph node metastases were more likely in patients with FNMTC, although we could not estimate prognosis. All patients with thyroid cancer should be checked for family disease history and undergo preoperative ultrasonography to determine the extent of node dissection and the need for total thyroidectomy.

Thyroid cancer risk factors and Pakistani University students' awareness towards its preventive practice

OBJECTIVES

Thyroid Cancer is one of the rarest cancers but its prevalence has been increasing worldwide for the last couple of decades.

METHODS

The data collection tool was designed to assess knowledge, awareness, perception, and attitude towards preventive practices of thyroid cancer in Pakistani university students. The data were collected over a duration of six months and a total number of 3722 students participated.

RESULTS

The knowledge of risk factors of thyroid cancer was an important parameter of this study. The students who knew all the early signs of thyroid cancer were 28.7%. In this study, the independent variables such as age, gender, demographic location, and financial status were found to be highly significant with knowledge, attitude towards warning signs of cancer, and the perception of students about developing thyroid cancer.

CONCLUSIONS

The participants were found to have poor knowledge about early signs of thyroid cancer. The study participants perception, behavior, and attitude towards preventive practices of thyroid cancer were found inadequate and appropriate measures on a National level should be taken to enhance the knowledge about preventive practices of thyroid cancer. Increasing knowledge and awareness shall help decrease the overall morbidity and mortality linked with thyroid carcinomas and thyroid diseases.

FOXE1 regulates migration and invasion in thyroid cancer cells and targets ZEB1

FOXE1 is a thyroid-specific transcription factor essential for thyroid gland development and maintenance of the differentiated state. Interestingly, a strong association has been recently described between FOXE1 expression and susceptibility to thyroid cancer, but little is known about the mechanisms underlying FOXE1-induced thyroid tumorigenesis. Here, we used a panel of human thyroid cancer-derived cell lines covering the spectrum of thyroid cancer phenotypes to examine FOXE1 expression and to test for correlations between FOXE1 expression, the allele frequency of two SNPs and a length polymorphism in or near the FOXE1 locus associated with cancer susceptibility, and the migration ability of thyroid cancer cell lines. Results showed that FOXE1 expression correlated with differentiation status according to histological sub-type, but not with SNP genotype or cell migration ability. However, loss-and-gain-of-function experiments revealed that FOXE1 modulates cell migration, suggesting a role in epithelial-to-mesenchymal transition (EMT). Our previous genome-wide expression analysis identified Zeb1, a major EMT inducer, as a putative Foxe1 target gene. Indeed, gene silencing of FOXE1 decreased ZEB1 expression, whereas its overexpression increased ZEB1 transcriptional activity. FOXE1 was found to directly interact with the ZEB1 promoter. Lastly, ZEB1 silencing decreased the ability of thyroid tumoral cells to migrate and invade, pointing to its importance in thyroid tumor mestastases. In conclusion, we have identified ZEB1 as a bona fide target of FOXE1 in thyroid cancer cells, which provides new insights into the role of FOXE1 in regulating cell migration and invasion in thyroid cancer.

Thyroid nodules: diagnostic evaluation based on thyroid cancer risk assessment

Thyroid nodules are extremely common and can be detected by sensitive imaging in more than 60% of the general population. They are often identified in patients without symptoms who are undergoing evaluation for other medical complaints. Indiscriminate evaluation of thyroid nodules with thyroid biopsy could cause a harmful epidemic of diagnoses of thyroid cancer, but inadequate selection of thyroid nodules for biopsy can lead to missed diagnoses of clinically relevant thyroid cancer. Recent clinical guidelines advocate a more conservative approach in the evaluation of thyroid nodules based on risk assessment for thyroid cancer, as determined by clinical and ultrasound features to guide the need for biopsy. Moreover, newer evidence suggests that for patients with indeterminate thyroid biopsy results, a combined assessment including the initial ultrasound risk stratification or other ancillary testing (molecular markers, second opinion on thyroid cytology) can further clarify the risk of thyroid cancer and the management strategies. This review summarizes the clinical importance of adequate evaluation of thyroid nodules, focuses on the clinical evidence for diagnostic tests that can clarify the risk of thyroid cancer, and highlights the importance of considering the patient's values and preferences when deciding on management strategies in the setting of uncertainty about the risk of thyroid cancer.

Current Knowledge of Germline Genetic Risk Factors for the Development of Non-Medullary Thyroid Cancer

The thyroid is the most common site of endocrine cancer. One type of thyroid cancer, non-medullary thyroid cancer (NMTC), develops from follicular cells and represents approximately 90% of all thyroid cancers. Approximately 5%–15% of NMTC cases are thought to be of familial origin (FNMTC), which is defined as the occurrence of the disease in three or more first-degree relatives of the patient. It is often divided into two groups: Syndrome-associated and non-syndromic. The associated syndromes include Cowden syndrome, familial adenomatous polyposis, Gardner syndrome, Carney complex and Werner syndrome. The hereditary factors contributing to the unfavorable course of FNMTC remain poorly understood; therefore, considerable effort is being expended to identify contributing loci. Research carried out to date identifies fourteen genes (DICER1, FOXE1, PTCSC2, MYH9, SRGAP1, HABP2, BRCA1, CHEK2, ATM, RASAL1, SRRM2, XRCC1, TITF-1/NKX2.1, PTCSC3) associated with vulnerability to FNMTC that are not related to hereditary syndromes. In this review, we summarize FNMTC studies to date, and provide information on genes involved in the development of non-syndromic familial non-medullary thyroid cancers, and the significance of mutations in these genes as risk factors. Moreover, we discuss whether the genetic polymorphism rs966423 in DIRC3 has any potential as a prognostic factor of papillary thyroid cancer.

Evolving Understanding of the Epidemiology of Thyroid Cancer

The incidence of thyroid cancer worldwide has increased significantly over the past 3 decades, due predominantly to an increase in papillary thyroid cancer. Although most of these cancers are small and localized, population-based studies have documented a significant increase in thyroid cancers of all sizes and stages, in addition to incidence-based mortality for papillary thyroid cancer. This suggests that the increasing incidence of thyroid cancer is due in large part to increasing surveillance and overdiagnosis, but that there also appears to be a true increase in new cases of thyroid cancer.

Thyroid transcription factor FOXE1 interacts with ETS factor ELK1 to co-regulate TERT

BACKGROUND

Although FOXE1 was initially recognized for its role in thyroid organogenesis, more recently a strong association has been identified between the FOXE1 locus and thyroid cancer. The role of FOXE1 in adult thyroid, and in particular regarding cancer risk, has not been well established. We hypothesised that discovering key FOXE1 transcriptional partners would in turn identify regulatory pathways relevant to its role in oncogenesis.

RESULTS

In a transcription factor-binding array, ELK1 was identified to bind FOXE1. We confirmed this physical association in heterologously transfected cells by IP and mammalian two-hybrid assays. In thyroid tissue, endogenous FOXE1 was shown to bind ELK1, and using ChIP assays these factors bound thyroid-relevant gene promoters TPO and TERT in close proximity to each other. Using a combination of electromobility shift assays, TERT promoter assays and siRNA-silencing, we found that FOXE1 positively regulated TERT expression in a manner dependent upon its association with ELK1. Treating heterologously transfected thyroid cells with MEK inhibitor U0126 inhibited FOXE1-ELK1 interaction, and reduced TERT and TPO promoter activity.

METHODOLOGY

We investigated FOXE1 interactions within in vitro thyroid cell models and human thyroid tissue using a combination of immunoprecipitation (IP), chromatin IP (ChIP) and gene reporter assays.

CONCLUSIONS

FOXE1 interacts with ELK1 on thyroid relevant gene promoters, establishing a new regulatory pathway for its role in adult thyroid function. Co-regulation of TERT suggests a mechanism by which allelic variants in/near FOXE1 are associated with thyroid cancer risk.

Interplay between Body Size Measures and Thyroid Cancer Aggressiveness: A Retrospective Analysis

Considering controversial data about the relationship between body size and prognosis of differentiated thyroid cancer (DTC), the current study aimed to assess the influence of body weight, body mass index (BMI), and body surface area (BSA) on DTC. We conducted a retrospective analysis of patients' records from the Thyroid Cancer Unit, assessing body size measures, clinical and laboratory prognostic factors, and disease evolution. 337 patients, aged 45.95 ± 13.04 years old, with BMI of 27.87 ± 5.13 kg/m² and BSA of 1.74 ± 0.18 m² were enrolled. After 9.5 ± 6.9 years of follow-up, 87.29% of patients were disease-free and 12.71% had persistent disease; no patient had deceased. Patients aged <45 years old with extrathyroidal invasion tumor had greater baseline body weight and BSA than those without extrathyroidal invasion (median 79.5 kg versus 67 kg and 1.85 m² versus 1.74 m²). Women with poorly differentiated tumor and patients aged ≥45 years old with distant metastasis presented greater weight loss during follow-up compared to patients without such characteristics (median -2 kg versus +1.5 kg and -3 kg versus +1 kg, respectively). The relationship between body size and DTC evolution was not observed. In conclusion, higher weight and BSA were associated with a greater chance of extrathyroidal tumor invasion in younger patients. Specific subgroups of patients with aggressive disease presented higher weight loss. Young patients with higher BSA should be carefully treated due to possible worse prognosis related to increased incidence of extrathyroid invasion. Findings related to tumor aggressiveness and weight loss in specific groups deserve further mechanistic studies.

Imaging and Screening of Thyroid Cancer

Ultrasound is the first-line diagnostic tool for diagnosis of thyroid diseases. The low aggressiveness of many thyroid cancers coupled with high sensitivity of sonography can lead to cancer diagnosis and treatment with no effect on outcomes. Ultrasound is recognized as the most important driver of thyroid cancer overdiagnosis. Ultrasound should not be used as a general screening tool and should be reserved for patients at high risk of thyroid cancer and in the diagnostic management of incidentally discovered thyroid nodules. With prescreening risk stratification and application of consensus criteria for nodule biopsy, the value of the diagnostic ultrasound can be maximized.

Is familial papillary thyroid microcarcinoma more aggressive than sporadic form?

Purpose

With the increasing incidence of papillary thyroid microcarcinoma (PTMC), familial papillary thyroid microcarcinoma (FPTMC) is now recognized more frequently. However, the biological behavior of FPTMC is poorly understood. The aim of this study was to investigate the prevalence of FPTMC and its biological aggressiveness.

Methods

Between March 2006 and July 2010, 2,414 patients underwent primary surgical therapy for PTMC and 149 (6.2%) were further classified as FPTMC. To determine the biological aggressiveness of FPTMC, we compared the clinicopathological features and prognosis between FPTMC and sporadic PTMC (SPTMC).

Results

The male-to-female ratio was higher in FPTMC than in sporadic papillary thyroid microcarcinoma (SPTMC: 1:4.5 vs. 1:7.2, P = 0.041). The central lymph node (LN) metastasis rate was significantly higher in FPTMC than in SPTMC (36.2% vs. 24.2%, P = 0.002). The local recurrence rate was also higher in FPTMC than in SPTMC (4.5% vs. 0.6%, P < 0.001). We identified familial occurrence in 6.2% of cases of PTMC. FPTMC is associated with a high rate of central LN metastasis and local recurrence.

Conclusion

These findings suggest that close follow-up can be beneficial in FPTMC patients to detect local recurrence.

The impact of family history on non-medullary thyroid cancer

INTRODUCTION

Around 10% of patients with non-medullary thyroid cancer (NMTC) will have a positive family history for the disease. Although many will be sporadic, families where 3 first-degree relatives are affected can be considered to represent true familial non-medullary thyroid cancer (FNMTC). The genetic basis, impact on clinical and pathological features, and overall effect on prognosis are poorly understood.

METHODS

A literature review identified articles which report on genetic, clinical, therapeutic and screening aspects of FNMTC. The results are presented to allow an understanding of the genetic basis and the impact on clinical-pathological features and prognosis in order to inform clinical decision making.

RESULTS

The genetic basis of FNMTC is unknown. Despite this, significant progress has been made in identifying potential susceptibility genes. The lack of a test for FNMTC has led to a clinical definition requiring a minimum of 3 first-degree relatives to be diagnosed with NMTC. Although some have shown an association with multi-centric disease, younger age and increased rates of extra-thyroidal extension and nodal metastases, these findings are not supported by all. The impact of FNMTC is unclear with all groups reporting good outcome, and some finding an association with more aggressive disease. The role of screening remains controversial.

CONCLUSION

FNMTC is rare but can be diagnosed clinically. Its impact on prognostic factors and the subsequent role in influencing management is debated. For those patients who present with otherwise low-risk differentiated thyroid cancer, FNMTC should be included in risk assessment when discussing therapeutic options.

Diagnosis and Management of Hereditary Thyroid Cancer

Thyroid cancers are largely divided into medullary (MTC) and non-medullary (NMTC) cancers , depending on the cell type of origin. Familial non-medullary thyroid cancer (FNMTC) comprises about 5-15% of NMTC and is a heterogeneous group of diseases, including both non-syndromic and syndromic forms. Non-syndromic FNMTC tends to manifest papillary thyroid carcinoma , usually multifocal and bilateral . Several high-penetrance genes for FNMTC have been identified, but they are often confined to a few or single families, and other susceptibility loci appear to play a small part, conferring only small increments in risk. Familial susceptibility is likely to be due to a combination of genetic and environmental influences. The current focus of research in FNMTC is to characterise the susceptibility genes and their role in carcinogenesis. FNMTC can also occur as a part of multitumour genetic syndromes such as familial adenomatous polyposis , Cowden's disease , Werner's syndrome and Carney complex . These tend to present at an early age and are multicentric and bilateral with distinct pathology. The clinical evaluation of these patients is similar to that for most patients with a thyroid nodule. Medullary thyroid cancer (MTC) arises from the parafollicular cells of the thyroid which release calcitonin. The familial form of MTC accounts for 20-25% of cases and presents as a part of the multiple endocrine neoplasia type 2 (MEN 2) syndromes or as a pure familial MTC (FMTC). They are caused by germline point mutations in the RET oncogene on chromosome 10q11.2. There is a clear genotype-phenotype correlation, and the aggressiveness of FMTC depends on the specific genetic mutation, which should determine the timing of surgery.

Targeted DNA Sequencing Detects Mutations Related to Susceptibility among Familial Non-medullary Thyroid Cancer

Some studies have demonstrated that familial non-medullary thyroid cancer (FNMTC) has a more aggressive clinical behavior compared to sporadic NMTC (SNMTC). However, FNMTC is difficult to differentiate from SNMTC by the morphology and immunohistochemistry. Although genes responsible for FNMTC were unclear, screening for rare germline mutations on known important tumor suppressor genes might offer more insights on predicting susceptibility to FNMTC. Here, a customized panel was designed to capture all exons of 31 cancer susceptive genes possibly related to FNMTC. Using next-generation sequencing we performed deep sequencing to achieve 500× coverage of the targeted regions. At the end 45 variants were identified in 29 of 47 familial patients and 6 of 16 sporadic patients. Notably, several germline mutations were found matching between paired FNMTC patients from the same family, including APC L292F and A2778S, BRAF D22N, MSH6 G355S and A36V, MSH2 L719F, MEN1 G508D, BRCA1 SS955S, BRCA2 G2508S, and a GNAS inframe insertion. We demonstrated a novel approach to help diagnose and elucidate the genetic cause of the FNMTC patients, and assess whether their family members are exposed to a higher genetic risk. The findings would also provide insights on monitoring the potential second cancers for thyroid cancer patients.

No evidence for a decreased risk of thyroid cancer in association with use of metformin or other antidiabetic drugs: a case-control study

Background

Use of metformin has been associated with a decreased cancer risk. We aimed to explore whether use of metformin or other antidiabetic drugs is associated with a decreased risk for thyroid cancer.

Methods

We conducted a case-control analysis (1995 to 2014) using the U.K.-based Clinical Practice Research Datalink (CPRD). Cases had a first-time diagnosis of thyroid cancer, six controls per case were matched on age, sex, calendar time, general practice, and number of years of active history in the database prior to the index date. We assessed odds ratios (ORs) with 95 % confidence intervals (95 % CI), adjusted for body mass index (BMI), smoking, and diabetes mellitus.

Results

In 1229 cases and 7374 matched controls, the risk of thyroid cancer associated with ever use of metformin yielded an adjusted OR of 1.48, 95 % CI 0.86–2.54. The relative risk estimate was highest in long-term (≥30 prescriptions) users of metformin (adjusted OR 1.83, 95 % CI 0.92–3.65), based on a limited number of 26 exposed cases. No such association was found in users of sulfonylurea, insulin, or thiazolidinediones (TZD). Neither a diabetes diagnosis (adjusted OR 1.17, 95 % CI 0.89–1.54), nor diabetes duration >8 years (adjusted OR 1.22, 95 % CI 0.60–2.51) altered the risk of thyroid cancer.

Conclusion

In our observational study with limited statistical power, neither use of metformin nor of other antidiabetic drugs were associated with a decreased risk of thyroid cancer.

Clinicopathologic features of familial nonmedullary thyroid carcinoma

BACKGROUND

Familial nonmedullary thyroid carcinoma (FNMTC) is a variant of nonmedullary thyroid carcinoma(NMTC) with particular clinicopathologic features. In recent years, a number of studies have shown that FNMTC is more invasive than sporadic NMTC(SNMTC). The purpose of this study was to explore the differences in clinicopathologic features of FNMTC between different types of families and to determine in which of these families more invasive FNMTC occurred.

METHODS

We retrospectively reviewed all patients with thyroid carcinoma admitted to Peking Union Medical College Hospital from January 2009 to July 2013 in the database. Of all 2000 cases, 55 met the inclusive criteria for FNMTC and were studied. There are two different grouping methods. The first is that all samples were allocated to families with three or more first-degree relatives affected (FNMTC-3 group) and families with only two affected first-degree relatives (FNMTC-2 group). The second is that all patients were divided into families with three or more affected first-degree relatives over two generations (FNMTC-3-2 group) and the other families. We compared the clinicopathologic features such as sex, age, tumor size, multifocality, location, complications by thyroiditis, complications by benign thyroid nodules, surgical procedure, capsule invasion, histological type, lymph node metastases, tumor node metastasis stage, and BRAF mutation between FNMTC-2 group and FNMTC-3 group. We also made the same comparison between FNMTC-3-2 group and other families.

RESULTS

No pronounced differences in clinicopathological features were present between FNMTC-2 group and FNMTC-3 group. The proportion of FNMTC-3-2 group aged <45 years was significantly higher than that in the other families (58.8% vs. 26.3%, P = 0.021). A similar difference was found in the proportion of lymph node metastasis (64.7% vs. 34.2%, P = 0.035).

CONCLUSIONS

FNMTC-3-2 is more invasive than the other families. Early screening and positive treatment for members of these families are recommended.

Single-center study of familial papillary thyroid cancer in China: surgical considerations

Background

Whether familial papillary thyroid cancer (FPTC) is more aggressive than sporadic counterpart remains elusive, and the optimal clinical approach for FPTC is yet to be established. In this study, we investigated familial occurrence of PTC in China and reviewed our experience of its surgical treatment.

Methods

The clinical records of 248 consecutive patients with an established diagnosis of PTC who were admitted to Nanfang Hospital for thyroidectomy between January 2011 and June 2013 were analyzed in this study. Patients included 66 males and 182 females, aged 11 to 76 years.

Results

Twenty-two patients (8.9%) with a positive family history were confirmed. Patients with FPTC had a predilection for female subjects and tended to be younger than other patients, but the difference was not significant (P = 0.0514 and P = 0.168). They were more likely to present large tumors (P = 0.0024), multifocality (familial vs. sporadic: 54.50% vs. 26.50%; P < 0.006), local invasion (81.8% vs. 23.9%; P < 0.001), and malignant lymph nodes (63.6% vs. 33.6%; P = 0.005). Univariate and multivariate analyses identified that a positive family history was an independent risk factor for local invasion (OR: 5.683; 95% CI: 2.056 to 15.707; P = 0.001), malignant lymph nodes (OR: 3.005; 95% CI: 1.046 to 8.630; P = 0.041) in FPTC patients. Kaplan-Meier survival curves revealed that an aggressive surgical strategy was associated with a better relapse-free survival than conventional one (P = 0.032).

Conclusions

FPTC is more likely to possess aggressive features than sporadic counterparts. Thus, screening of at-risk families is essential to aid in earlier recognition. An aggressive surgical strategy appeared to be the more effective therapy. However, sufficient detailed interrogation and long-term follow-up of the patients and their family are necessary for providing individualized recommendations for clinical management.

Association of radiation dose with prevalence of thyroid nodules among atomic bomb survivors exposed in childhood (2007-2011)

IMPORTANCE

Few studies have evaluated the association of radiation dose with thyroid nodules among adults exposed to radiation in childhood.

OBJECTIVE

To evaluate radiation dose responses on the prevalence of thyroid nodules in atomic bomb survivors exposed in childhood.

DESIGN, SETTING, AND PARTICIPANTS

This survey study investigated 3087 Hiroshima and Nagasaki atomic bomb survivors who were younger than 10 years at exposure and participated in the thyroid study of the Adult Health Study at the Radiation Effects Research Foundation. Thyroid examinations including thyroid ultrasonography were conducted between October 2007 and October 2011, and solid nodules underwent fine-needle aspiration biopsy. Data from 2668 participants (86.4% of the total participants; mean age, 68.2 years; 1213 men; and 1455 women) with known atomic bomb thyroid radiation doses (mean dose, 0.182 Gy; median dose, 0.018 Gy; dose range, 0-4.040 Gy) were analyzed.

MAIN OUTCOMES AND MEASURES

The prevalence of all thyroid nodules having a diameter of 10 mm or more (consisting of solid nodules [malignant and benign] and cysts), prevalence of small thyroid nodules that were less than 10 mm in diameter detected by ultrasonography, and atomic bomb radiation dose-responses.

RESULTS

Thyroid nodules with a diameter of 10 mm or more were identified in 470 participants (17.6%): solid nodules (427 cases [16.0%]), malignant tumors (47 cases [1.8%]), benign nodules (186 cases [7.0%]), and cysts (49 cases [1.8%]), and all were significantly associated with thyroid radiation dose. Excess odds ratios per gray unit were 1.65 (95% CI, 0.89-2.64) for all nodules, 1.72 (95% CI, 0.93-2.75) for solid nodules, 4.40 (95% CI, 1.75-9.97) for malignant tumors, 2.07 (95% CI, 1.16-3.39) for benign nodules, and 1.11 (95% CI, 0.15-3.12) for cysts. The interaction between age at exposure and the dose was significant for the prevalence of all nodules (P = .003) and solid nodules (P < .001), indicating that dose effects were significantly higher with earlier childhood exposure. No interactions were seen for sex, family history of thyroid disease, antithyroid antibodies, or seaweed intake. No dose-response relationships were observed for small (<10-mm diameter) thyroid nodules.

CONCLUSIONS AND RELEVANCE

Radiation effects on thyroid nodules exist in atomic bomb survivors 62 to 66 years after their exposure in childhood. However, radiation exposure is not associated with small thyroid nodules.

CHEK2 mutations and the risk of papillary thyroid cancer

Mutations in the cell cycle checkpoint kinase 2 (CHEK2) tumor suppressor gene are associated with multi-organ cancer susceptibility including cancers of the breast and prostate. A genetic association between thyroid and breast cancer has been suggested, however little is known about the determinants of this association. To characterize the association of CHEK2 mutations with thyroid cancer, we genotyped 468 unselected patients with papillary thyroid cancer and 468 (matched) cancer-free controls for four founder mutations of CHEK2 (1100delC, IVS2 + 1G>A, del5395 and I157T). We compared the family histories reported by patients with a CHEK2 mutation to those of non-carriers. A CHEK2 mutation was seen in 73 of 468 (15.6%) unselected patients with papillary thyroid cancer, compared to 28 of 460 (6.0%) age- and sex-matched controls (OR 3.3; p < 0.0001). A truncating mutation (IVS2 + 1G>A, 1100delC or del5395) was associated with a higher risk of thyroid cancer (OR = 5.7; p = 0.006), than was the missense mutation I157T (OR = 2.8; p = 0.0001). CHEK2 mutation carriers reported a family history of breast cancer 2.2 times more commonly than non-carriers (16.4% vs.8.1%; p = 0.05). A CHEK2 mutation was found in seven of 11 women (63%) with multiple primary cancers of the breast and thyroid (OR = 10; p = 0.0004). These results suggest that CHEK2 mutations predispose to thyroid cancer, familial aggregations of breast and thyroid cancer and to double primary cancers of the breast and thyroid.

Modifiable risk factors and thyroid cancer

OBJECTIVE

To evaluate the association between modifiable patient risk factors including tobacco use, alcohol consumption, body mass index (BMI), and thyroid cancer.

STUDY DESIGN

Retrospective study with chart review.

SETTING

Midwest university hospital.

SUBJECTS AND METHODS

Retrospective study comparing Midwest patients with thyroid cancer from our Thyroid Tumor and Cancer Registry with Midwest controls without a personal history of cancer. Descriptive statistics were created from patient questionnaires and chart reviews. Odds ratios (ORs) were reported for significant associations.

RESULTS

There were 467 patients with cancer and 255 controls. The thyroid cancer group included 404 papillary, 47 follicular, 13 medullary, and 3 anaplastic cancers. When comparing all patients with cancer with controls, smoking more than 100 lifetime cigarettes was associated with a reduced cancer risk (OR, 0.68; 95% confidence interval [CI], 0.50-0.94). Secondhand smoke exposure did not show a statistically significant relationship to thyroid cancer. Compared with never drinking, current drinking was associated with a reduced cancer risk (OR, 0.46; 95% CI, 0.29-0.73) as was consuming 1 to 2 drinks daily compared to drinking <1 drink daily (OR, 0.58; 95% CI, 0.34-0.89). There was no difference between median BMI at age 20 years, lifetime maximum BMI, or current BMI between patients with cancer and controls.

CONCLUSION

Our data showed no positive correlation between tobacco use, alcohol consumption, or obesity and thyroid cancer risk. Our data suggest that tobacco use and mild alcohol consumption may be associated with a slightly reduced risk of thyroid cancer. There was no association between BMI and thyroid cancer in our study population.

Risk-based ultrasound screening for thyroid cancer in obese patients is cost-effective

BACKGROUND

A higher body mass index (BMI) is associated with more advanced stages of thyroid cancer. Screening obese patients for thyroid cancer has been proposed but has yet to be examined for cost-effectiveness. The objective of this study was to assess the cost-effectiveness of ultrasound (US) screening of obese patients for thyroid cancer.

METHODS

A decision-tree model compared cost savings for the following: (i) base case scenario of an obese patient with thyroid nodule found by palpation, (ii) universal US screening of all obese patients, and (iii) risk-based US screening in obese patients. Risk-based screening consisted of patients who had at least one of four major identified risk factors for thyroid cancer (family history of thyroid cancer, radiation exposure, Hashimoto's thyroiditis, and/or elevated thyrotropin). Patients with nodules underwent established treatment and management guidelines. The model accounted for recurrence, complications, and long-term treatment/follow-up for five years. Outcome probabilities were identified from a literature review. Costs were estimated using a third-party payer perspective. Sensitivity analyses were performed to examine the impact of risk factor prevalence and US cost on the model.

RESULTS

The resulted costs per patient were $210.73 in the base case scenario, $434.10 in the universal US screening arm, and $166.72 in the risk-based screening arm. Risk-based screening remained cost-effective until more than 14% of obese patients had risk factors and with a wide variation of US costs ($0-$1113).

CONCLUSION

Risk-based US screening in selected obese patients with risk factors for thyroid cancer is cost-effective. Recommendations for screening this subgroup will result in cost savings and a likely decreased morbidity and mortality in this subpopulation with more aggressive disease.

Cancerogenesis Risks between 64 and 320 Row Detector CT for Coronary CTA Screening

OBJECTIVES

This study compares cancerogenesis risks posed by the 64 row detector and the 320 row detector computed tomography scanners used during coronary computed tomography angiography (CCTA) following decennial screening guidelines.

MATERIAL AND METHODS

Data of the radiation absorbed after CCTA by lung, thyroid, and female breast in patients between 50 and 70 years of age obtained from prior published literature for the 64 row CT scanner were compared with data from our study using 320 row detector CT scanner. Data from the 64 row and the 320 row detector CT scanners was used to determine lifetime attributable risks (LAR) of cancer based on the biological effects of ionizing radiation (BEIR) VII report.

RESULTS

The relative reduction of LAR (%) for 50-, 60-, and 70-year-old patients undergoing scanning with the 320 row detector CT scanner was 30% lower for lung, and more than 50% lower for female breast when compared with results from 64 row detector CT scanner. The use of 320 row detector CT would result in a combined cumulative cancer incidence of less than 1/500 for breast in women and less than 1/1000 for lung in men; By comparison, this is much lower than other more common risk factors: 16-fold for lung cancer in persistent smokers, 2-fold for breast cancer with a first degree family member history of breast cancer, and 10-fold for thyroid cancer with a family member with thyroid cancer. Decennial screening would benefit at least 355,000 patients from sudden cardiac death each year, 94% of whom have significant coronary artery disease, with at least one stenosis >75%. LAR for thyroid cancer was negligible for both scanners.

CONCLUSION

Lung and female breast LAR reductions with 320 row detector compared with 64 row detector CT are substantial, and the benefits would outweigh increased cancer risks with decennial screening in the age group of 50-70 years.

Controversies in familial thyroid cancer 2014

Thyroid cancer is the sixth most common cancer in women, and the majority of patients with thyroid cancer has sporadic disease. However, about 25% of patients with medullary thyroid cancer and 5% with papillary thyroid cancer have familial tumors. Currently, there are numerous controversies regarding the mode of inheritance, tumor behavior, extent of surgical resection for optimal results, coexisting thyroid pathology, risk of other cancers, and extent of postoperative treatment of patients with familial thyroid cancer. This review aimed to give insight to surgeons on this interesting topic.

Familial history of non-medullary thyroid cancer is an independent prognostic factor for tumor recurrence in younger patients with conventional papillary thyroid carcinoma

BACKGROUND

It is not clear whether familial non-medullary thyroid cancer (FNMTC) is more aggressive and has a poorer prognosis, than sporadic carcinoma. Therefore, the optimal clinical approach for FNMTC is yet to be established. In this study, we investigated the biological behavior and prognosis of FNMTC compared with its sporadic counterpart.

METHODS

Between 1996 and 2004, 1,262 patients underwent a total thyroidectomy for conventional PTC at Asan Medical Center and 113 (9.0%) were diagnosed with FNMTC. We compared the clinico-pathologic characteristics, treatment modalities, and prognosis between familial and sporadic NMTC.

RESULTS

FNMTC was significantly more multi-centric than sporadic. We also found that family history itself was an independent risk factor for recurrence. Moreover, disease-free survival in the familial group was significantly shorter than in the sporadic group in the subgroups in which age was <45 years, and in which the tumors were multi-centric, bilateral, and of N1b node status.

CONCLUSION

FNMTC may be considered as a separate clinical entity with a higher rate of recurrence and worse DFS than its sporadic counterpart. Furthermore, familial history of NMTC is an independent risk factor for recurrence, especially in younger patients with conventional PTC.

An epistatic interaction between the PAX8 and STK17B genes in papillary thyroid cancer susceptibility

Papillary Thyroid Cancer (PTC) is a heterogeneous and complex disease; susceptibility to PTC is influenced by the joint effects of multiple common, low-penetrance genes, although relatively few have been identified to date. Here we applied a rigorous combined approach to assess both the individual and epistatic contributions of genetic factors to PTC susceptibility, based on one of the largest series of thyroid cancer cases described to date. In addition to identifying the involvement of TSHR variation in classic PTC, our pioneer study of epistasis revealed a significant interaction between variants in STK17B and PAX8. The interaction was detected by MD-MBR (p = 0.00010) and confirmed by other methods, and then replicated in a second independent series of patients (MD-MBR p = 0.017). Furthermore, we demonstrated an inverse correlation between expression of PAX8 and STK17B in a set of cell lines derived from human thyroid carcinomas. Overall, our work sheds additional light on the genetic basis of thyroid cancer susceptibility, and suggests a new direction for the exploration of the inherited genetic contribution to disease using association studies.

Solid tumors after chemotherapy or surgery for testicular nonseminoma: a population-based study

PURPOSE

Increased risks of solid tumors after older radiotherapy strategies for testicular cancer (TC) are well established. Few population-based studies, however, focus on solid cancer risk among survivors of TC managed with nonradiotherapy approaches. We quantified the site-specific risk of solid cancers among testicular nonseminoma patients treated in the modern era of cisplatin-based chemotherapy, without radiotherapy.

PATIENTS AND METHODS

Standardized incidence ratios (SIRs) for solid tumors were calculated for 12,691 patients with testicular nonseminoma reported to the population-based Surveillance, Epidemiology, and End Results program (1980 to 2008) and treated initially with either chemotherapy (n = 6,013) or surgery (n = 6,678) without radiotherapy. Patients accrued 116,073 person-years of follow-up.

RESULTS

Two hundred ten second solid cancers were observed. No increased risk followed surgery alone (SIR, 0.93; 95% CI, 0.76 to 1.14; n = 99 solid cancers), whereas significantly increased 40% excesses (SIR, 1.43; 95% CI, 1.18 to 1.73; n = 111 solid cancers) occurred after chemotherapy. Increased risks of solid cancers after chemotherapy were observed in most follow-up periods (median latency, 12.5 years), including more than 20 years after treatment (SIR, 1.54; 95% CI, 0.96 to 2.33); significantly increased three- to seven-fold risks occurred for cancers of the kidney (SIR, 3.37; 95% CI, 1.79 to 5.77), thyroid (SIR, 4.40; 95% CI, 2.19 to 7.88), and soft tissue (SIR, 7.49; 95% CI, 3.59 to 13.78).

CONCLUSION

To our knowledge, this is the first large population-based series reporting significantly increased risks of solid cancers among patients with testicular nonseminoma treated in the modern era of cisplatin-based chemotherapy. Subsequent analytic studies should focus on the evaluation of dose-response relationships, types of solid cancers, latency patterns, and interactions with other possible factors, including genetic susceptibility.

Analysis of loss of heterozygsity effect on thyroid tumor with oxyphilia cell locus in familial non medullary thyroid carcinoma in Iranian families

MATERIAL AND METHODS

22 nuclear families (78 persons including 12 patients) with papillary and follicular tumors were selected in a period of six months from Milad hospital. Five microsatellite markers (D19S413, D19S391, D19S916, D19S568, D19S865) on 19p13.2 were selected for genetic analysis. Genomic DNAs was extracted; PCR and polyacrylamide gel electrophoresis method were used for variation detection.

RESULTS

The results show that 5.4% of the follicular carcinomas and 17.9% of the papillary carcinomas presented LOH at recognition sites. LOH of Papillary carcinoma detected about 13.9% and follicular carcinoma 7.2% in this study. The frequency of informative cases was not similar for each marker: D19S413 (41.1%)[1], D19S391 (12.5%), D19S916 (10.7%), D19S568 (1.8%) and D19S865 (3.6%). Loss of hetrozygosity in D19S413 predicts the relation between variation in this region and the disease.

DISCUSSION

Our findings showed an average of 13.9% LOH in FNMTC cases. Among the five major microsatellites, D19S413 was the most informative for LOH analysis of FNMTC.

Ultra-rare mutation in long-range enhancer predisposes to thyroid carcinoma with high penetrance

Thyroid cancer shows high heritability but causative genes remain largely unknown. According to a common hypothesis the genetic predisposition to thyroid cancer is highly heterogeneous; being in part due to many different rare alleles. Here we used linkage analysis and targeted deep sequencing to detect a novel single-nucleotide mutation in chromosome 4q32 (4q32A>C) in a large pedigree displaying non-medullary thyroid carcinoma (NMTC). This mutation is generally ultra-rare; it was not found in 38 NMTC families, in 2676 sporadic NMTC cases or 2470 controls. The mutation is located in a long-range enhancer element whose ability to bind the transcription factors POU2F and YY1 is significantly impaired, with decreased activity in the presence of the C- allele compared with the wild type A-allele. An enhancer RNA (eRNA) is transcribed in thyroid tissue from this region and is greatly downregulated in NMTC tumors. We suggest that this is an example of an ultra-rare mutation predisposing to thyroid cancer with high penetrance.

The long-term outcomes of the second generation of familial nonmedullary thyroid carcinoma are more aggressive than sporadic cases

BACKGROUND

Familial nonmedullary thyroid carcinoma (FNMTC) is frequently detected, but the prevalence or the aggressiveness of FNMTC is still unclear. We aimed to investigate the prevalence, clinical characteristics, and prognosis of FNMTC.

METHODS

This study included 3056 nonmedullary thyroid carcinoma (NMTC) patients who were pathologically confirmed to exhibit differentiated thyroid carcinoma from January 1962 through March 2010. The duration of follow-up was 6.2±6.2 years.

RESULTS

The prevalence of FNMTC was 9.6%; 37.9% of the FNMTC patients exhibited a parent-offspring relationship, and 62.1% exhibited a sibling relationship. FNMTC was smaller in tumor size (1.2±0.9 vs. 1.4±1.1 cm) and more multifocal (33.6% vs. 27.0%) than sporadic cases. FNMTC presented higher recurrence rates (29.5% vs. 19.8%) and shorter recurrence-free survival than sporadic NMTC (p=0.046). When we compared sporadic NMTC with parent-offspring or sibling FNMTC separately, parent-offspring FNMTC was more multifocal (39.3% vs. 27.0%), while sibling FNMTC was more prevalent in female patients (89.6% vs. 82.5%) and presented smaller tumors (1.2±0.8 vs. 1.4±1.1 cm) than sporadic NMTC. The recurrence rate was higher than that of sporadic NMTC in parent-offspring FNMTC (35.6% vs. 19.8%) but not in sibling FNMTC. Among the 123 parent-offspring FNMTC cases, the second generation exhibited an earlier age at the diagnosis (38±11 vs. 57±11 years), more extrathyroidal invasion (57.8% vs. 29.4%), a higher recurrence rate (50.0% vs. 19.0%), and shorter recurrence-free survival (p=0.015) than the first generation.

CONCLUSION

FNMTC was found to have a very high prevalence in our population. Parent-offspring FNMTC demonstrated higher recurrence than sporadic NMTC; specifically, the second generation of parent-offspring FNMTC cases exhibited more aggressive clinical characteristics than the first generation.

Patients with familial non-medullary thyroid cancer have an outcome similar to that of patients with sporadic papillary thyroid tumors

OBJECTIVE

The purpose of this study was to determine whether familial non-medullary thyroid cancer (FNMTC) is more aggressive than sporadic thyroid cancer.

SUBJECTS AND METHODS

We compared the clinical behavior and outcome of 16 subjects with FNMTC from 7 unrelated kindred with those observed in 160 subjects with sporadic PTC (SPTC) from our database.

RESULTS

The only different baseline characteristics observed between both groups were: bilateral malignancy, 38% vs. 24%, respectively (p = 0.03), and lymph node metastasis, 56.2% vs. 39%, respectively (p = 0.01). Considering the outcome, in the FNMTC, 9 (56.2%) patients were rendered free of disease, one patient died from thyroid cancer (6%), and 6/16 (37.5%) had persistent disease. In the SPTC Group, 87 (54%) patients were considered free of disease, 11 (7%) died due to PTC, and 62 (38%) had persistent disease (p = ns).

CONCLUSIONS

Despite the higher incidence of lymph node metastasis in FNMTC patients this situation seemed not to alter the compared outcome.

Familial papillary thyroid carcinoma: a retrospective analysis

Background. Whether or not the familial form of papillary thyroid carcinoma is more aggressive than the sporadic form of the disease remains controversial. Methods. To explore this question and whether or not increased aggressiveness is more apparent in families with multiple affected members, we performed a chi square by trend analysis on our patients clinical and pathologic data comparing: first degree families with three or more affected members versus first degree families with two affected members versus sporadic cases of papillary thyroid carcinoma. Results. No statistically significant trends were seen for any presenting surgical pathology parameter, age at presentation, length of follow-up or gender distribution. The familial groups exhibited significant trends for higher rates of reoperation (P = 0.05) and/or requiring additional radioactive iodine therapy (P = 0.03), distant metastases (P = 0.003) and deaths (P = 0.01). These aggressive features were most apparent in certain families with three or more affected members. Conclusions. Using the chi square by trend analysis, a significant trend was seen for the familial form of papillary thyroid cancer to possess more aggressive features than the sporadic disease. Prompt recognition of the familial nature of the disease may provide earlier diagnosis and treatment in similarly affected family members.