Thyroid nodules and cancer in children and adolescents affected by autoimmune thyroiditis

Hashimoto's Thyroiditis and the Risk of Papillary Thyroid Cancer in Children

The association between Hashimoto's thyroiditis (HT) and pediatric thyroid cancer is controversial. Most studies examining this connection have been based on adults, and larger studies in children are lacking. We performed a retrospective study of all sequential pediatric patients who underwent a thyroidectomy for a neoplasm at our institution over a twenty-year period in order to explore the link between HT and pediatric thyroid cancer. A total of 153 patients, median age 16.5 (interquartile range [IQR] 14.2-18.3) years, underwent thyroid surgery for a neoplasm. Patients were mainly female (80%) and White (84%). Median follow-up was 58.6 (IQR 20.7-105.4) months. Thirty-five (23%) patients had HT. Patients who underwent thyroid surgery and had HT were more likely to harbor a malignant neoplasm (p = 0.05); specifically, papillary thyroid carcinoma (PTC, p = 0.02). There was a difference in the distribution of HT among the subtypes of PTC (p = 0.03). Despite this, there was no difference in terms of survival between patients with/without HT. In conclusion, children with a thyroid malignancy, specifically, PTC, are more likely to have HT. The association between HT and pediatric PTC appears to be subtype-specific but does not seem to affect patient survival.

Ultrasound, laboratory and histopathological insights in diagnosing papillary thyroid carcinoma in a paediatric population: a single centre follow-up study between 2000-2022

Background

Papillary thyroid carcinoma (PTC) often coincides with autoimmune thyroiditis (AIT); whether this association is incidental or causal remains debated.

Objective

To evaluate the ultrasonographic, laboratory, and histopathological features of PTC in paediatric patients with and without AIT and its relationship to puberty.

Design

A retrospective cohort study.

Patients and methods

A retrospective analysis of medical records of 90 patients (69; 76.7% females). The mean age at PTC diagnosis was 13.8 years [range 6-18]. All patients were evaluated ultrasonographically before thyroid surgery. Thyroid nodules were categorised using the European Thyroid Imaging Reporting and Data System (EU-TIRADS PL), and cytopathology was assessed using Bethesda criteria. Neck ultrasound results and thyroid and autoimmune status were correlated with histopathological PTC assessment.

Results

The coexistence of PTC and AIT was found in 48.9% (44/90) of patients. The percentage of AIT was increasing with age; AIT was present only in 1/3 of prepubertal, close to 50% in pubertal, and over 60% in adolescent patients. The youngest patients (aged <10 years old) presented more often with goitre and lymphadenopathy and less often with AIT than adolescents (15-18 years of age). There were no differences in TPOAb, TgAb, and TSH levels between the age subgroups. Presurgical TgAb levels were higher than those of TPOAb in the youngest patients. Histopathological analysis revealed that the solid subtype was observed more often in prepubertal children and diffuse sclerosing in children below 14 years of age, whereas the classic subtype dominated in late pubertal. Univariate and multivariate analyses revealed that lymph nodes metastases (LNM) were associated with PTC diameter and fT4 level, whereas extrathyroidal extension with age and angioinvasion with PTC diameter and age. The correlations between age and fibrosis, and the presence of psammoma bodies in malignant tissues were close to significant. We did not observe an association between TSH levels and the presence of autoimmunity and PTC variables.

Conclusions

In paediatric patients the natural course of PTC may be less aggressive in adolescent patients than in younger children (especially < 10 years of age). We suggest that pre-operative evaluation of paediatric patients with thyroid nodules could include apart from assessment of thyroid hormones, evaluation of TPOAb, TgAb, and TRAb together with comprehensive neck ultrasonography.

Ultrasound evolution of parenchymal changes in the thyroid gland with autoimmune thyroiditis in children prior to the development of papillary thyroid carcinoma - a follow-up study

Background

Follicular cell-derived thyroid carcinoma represents the vast majority of paediatric thyroid cancers (TCs). Papillary thyroid carcinoma (PTC) accounts for over 90% of all childhood TC cases, and its incidence in paediatric patients is increasing. The objective of this follow-up study was to present the outcome of ultrasound (US) and laboratory monitoring of paediatric patients with autoimmune thyroiditis (AIT) prior to the development of PTC.

Patients and methods

This prospective study included 180 children and adolescents (132 females; 73.3%) with a suspicion of thyroid disorder referred to the Outpatient Endocrine Department. The patients were divided into four groups: 1) 28 patients with a mean age of 10.7 [standard deviation (SD), 3.1] y, in whom PTC was detected during the active surveillance of AIT [AIT(+), PTC(+) follow up (F)]; 2) 18 patients with a mean age of 12.8 (SD, 3.4) y, in whom PTC and AIT were detected upon admission (A) [AIT(+), PTC(+) A]; 3) 45 patients with a mean age of 13.0 (SD, 3.4) y, in whom PTC was detected upon admission and AIT was excluded [AIT(-), PTC(+) A]; and 4) an age- and sex-matched control group of 89 patients with AIT and with a mean age of 9.4 (SD, 3.0) y. The analysis included clinical, US, and laboratory assessment results of children on admission (groups 1-4) and during follow-up (groups 1 and 4) in the Paediatric Endocrine Outpatient Department.

Results

Upon admission of those in group 1, the US evaluation revealed a hypoechogenic thyroid gland in 12 and an irregular normoechogenic gland in 16 patients. US monitoring revealed an increase in thyroid echogenicity and an increased irregularity of the thyroid structure during the follow-up period of all of the patients from group 1. Such changes were not noticed in group 4. PTC was diagnosed at the mean time of 3.6 y (3 mo-9 y) since AIT confirmation in group 1. The mean maximum PTC diameter as per the US was significantly smaller in group 1 than in groups 2 and 3 [13.2 (10.8) mm vs. 22.2 (12.8) and 22.05 (15.4) mm]. Fewer patients in group 1 were referred to 131I than in groups 2 and 3 (71.4% vs. 94.4 and 93.3%). Interestingly, significant differences were observed in the thyroglobulin antibody (TgAb)/thyroid peroxidase antibody (TPOAb) ratio between groups 2 and 3, as opposed to group 4, at the beginning of observation [15.3 (27.6) and 3.5 (8.8] vs. 0.77 (1.9)]. In group 1, after the follow-up, an increase in the TgAb/TPOAb ratio was observed [1.2 (9.8) to 5.2 (13.5)]. There were no significant differences between groups 1-3 in labeling index Ki67, lymph nodes metastasis, extrathyroidal extension, and angioinvasion. There were no associations between thyroid-stimulating hormone, TgAb, and the extent of the disease.

Conclusion

The use of thyroid US focused on the search for developing tumours in the routine follow-up of patients with AIT may not only help in the early detection of thyroid malignancies that are not clinically apparent but may also influence the invasiveness of oncological therapy and reduce the future side effects of 131I therapy. We propose that the repeat evaluation of TPOAb and TgAb warrants further exploration as a strategy to determine TC susceptibility in paediatric patients with AIT in larger multicentre studies.

Juvenile idiopathic arthritis patients with positive family history of autoimmune thyroid disease might benefit from serological screening: analysis of the international Pharmachild registry

BACKGROUND

Little is known about the association between juvenile idiopathic arthritis (JIA) and autoimmune thyroid disease (AITD) and therefore there are no indications for AITD screening in this population, which is possible using standard blood tests. The objective of this study is to determine the prevalence and predictors of symptomatic AITD in JIA patients from the international Pharmachild registry.

METHODS

Occurrence of AITD was determined from adverse event forms and comorbidity reports. Associated factors and independent predictors for AITD were determined using univariable and multivariable logistic regression analyses.

RESULTS

The prevalence of AITD after a median observation period of 5.5 years was 1.1% (96/8965 patients). Patients who developed AITD were more often female (83.3% vs. 68.0%), RF positive (10.0% vs. 4.3%) and ANA positive (55.7% vs. 41.5%) than patients who did not. AITD patients were furthermore older at JIA onset (median 7.8 years vs. 5.3 years) and had more often polyarthritis (40.6% vs. 30.4%) and a family history of AITD (27.5% vs. 4.8%) compared to non-AITD patients. A family history of AITD (OR = 6.8, 95% CI: 4.1 - 11.1), female sex (OR = 2.2, 95% CI: 1.3 - 4.3), ANA positivity (OR = 2.0, 95% CI: 1.3 - 3.2) and older age at JIA onset (OR = 1.1, 95% CI: 1.1 - 1.2) were independent predictors of AITD on multivariable analysis. Based on our data, 16 female ANA positive JIA patients with a family history of AITD would have to be screened during ±5.5 years using standard blood tests to detect one case of AITD.

CONCLUSIONS

This is the first study to report independent predictor variables for symptomatic AITD in JIA. Female ANA positive JIA patients with positive family history are at increased risk of developing AITD and thus might benefit from yearly serological screening.

Molecular Landscape of Pediatric Thyroid Cancer: A Review

Thyroid carcinomas (TC) are rare in the pediatric population; however, they constitute the most common endocrine malignancy. Despite some similarities with adult carcinomas, they have distinct clinical behavior and responses to therapy due to their unique pathology and molecular characteristics. The age cut-off used for defining the pediatric age group has been variable across different studies, and the universally accepted recommendations influence accurate interpretation of the available data. Moreover, factors such as radiation exposure and germline mutations have greater impact in children than in adults. Papillary TC is the most common and the most evaluated pediatric TC. Others, including follicular, poorly differentiated and medullary carcinomas, are rarer and have limited available literature. Most studies are from the West. Asian studies are primarily from Japan, with few from China, India, Saudi Arabia and Republic of Korea. This review provides a comprehensive account of the well-established and novel biomarkers in the field, including point mutations, fusions, miRNA, and thyroid differentiation genes. Familial and syndromic associations are also discussed. Current management guidelines for pediatric patients are largely derived from those for adults. An awareness of the molecular landscape is essential to acknowledge the uniqueness of these tumors and establish specific diagnostic and therapeutic guidelines.

Elastographic Evaluation of Thyroid Nodules in Children and Adolescents with Hashimoto’s Thyroiditis and Nodular Goiter with Reference to Cytological and/or Histopathological Diagnosis

There are data indicating the coexistence of papillary thyroid carcinoma and autoimmune thyroiditis (AIT) in children. The aim of the study was elastographic evaluation of thyroid nodules in children and adolescents with AIT and nodular goiter in relation to cytological and/or histopathological diagnosis. We examined 215 children (57 boys and 158 girls) with 261 thyroid nodules (143 non-AIT and 118 AIT). All study participants underwent a conventional ultrasound examination with elastography followed by fine needle aspiration biopsy (FNAB). Abnormal Strain Ratio (SR ≥ 5) was observed in 36 non-AIT nodules and 15 AIT nodules. Papillary thyroid carcinoma was diagnosed in 5 patients (2% of all investigated nodules). SR of malignant thyroid nodules was statistically higher in comparison to SR of benign nodules both in the group of non-AIT (6 ± 4 vs. 3.67 ± 2.62, p = 0.024) and AIT nodules (6.3 ± 0.01 vs. 2.92 ± 1.89, p = 0.047). Comparison of non-AIT and AIT benign nodules revealed that SR was higher in non-AIT nodules (3.67 ± 2.62 vs. 2.92 ± 1.89, p = 0.01). We observed a strong positive correlation (R = 1) between TSH concentration and SR ratio in the group of all malignant thyroid nodules. Autoimmune inflammatory process of the thyroid gland does not limit the use of elastography in the diagnosis of thyroid nodules in children.

Autoimmune Thyroiditis and Risk of Malignancy in Children with Thyroid Nodules

Background: It is uncertain whether the presence of autoimmune thyroiditis (AIT) increases the risk of thyroid cancer in children with thyroid nodules. This study evaluated the association between AIT and thyroid cancer in pediatric patients with thyroid nodules. Methods: A cross-sectional study was performed of pediatric patients (<19 years old) with a thyroid nodule (≥1 cm) who underwent fine-needle aspiration in an academic pediatric thyroid center. AIT was defined by the presence of thyroid autoantibodies or diffusely heterogeneous sonographic echotexture. The primary outcome was diagnosis of thyroid cancer. The association of AIT with thyroid cancer was evaluated with univariable and multivariable logistic regression. Associations of AIT with subject and nodule characteristics were also assessed. Results: Four hundred fifty-eight thyroid nodules in 385 patients (81% female) were evaluated at a median age of 15.5 years (interquartile range 13.5-17.0). Thyroid cancer was present in 108 nodules (24%). AIT was present in 95 subjects (25%) and was independently associated with an increased risk of thyroid cancer (multivariable odds ratio [OR] 2.19, 95% confidence interval [CI] 1.32-3.62). Thyroid cancer was also independently associated with younger age, nodule size, and solitary nodules, but was not associated with serum thyrotropin concentration. AIT was not associated with the likelihood of subjects undergoing thyroid surgery (p = 0.17). AIT was less commonly associated with follicular thyroid carcinoma than with papillary thyroid carcinoma (OR 0.22, CI 0.05-1.06). Among papillary thyroid carcinomas, AIT was strongly associated with the diffuse sclerosing variant (OR 4.74, CI 1.33-16.9). AIT was not associated with the extent of local, regional, or distant disease at thyroid cancer diagnosis. Conclusions: AIT is independently associated with an increased risk of thyroid cancer in children with thyroid nodules. These findings suggest that the evaluation of thyroid autoantibodies and thyroid echotexture may inform thyroid cancer risk assessment and surgical decision-making in children with thyroid nodules.

Diagnostic accuracy of ultrasonographic features in detecting thyroid cancer in the transition age: a meta-analysis

Context

Significant uncertainty exists about the diagnostic accuracy of ultrasonographic (US) features used to predict the risk of thyroid cancer in the pediatric population. Moreover, there are no specific indications for thyroid nodule evaluation in patients during the transition age.

Objective

The meta-analysis aimed to address the following question: which thyroid nodule US features have the highest accuracy in predicting malignancy in the transition age.

Methods

We performed a meta-analysis of observational/cohort/diagnostic accuracy studies dealing with thyroid nodule sonography, reporting US features, and using histology as a reference standard for the diagnosis of malignancy and histology or cytology for the diagnosis of benignity in the transition age (mean/median age 12-21 years).

Results

The inclusion criteria were met by 14 studies, published between 2005 and 2020, including 1306 thyroid nodules (mean size 17.9 mm) from 1168 subjects. The frequency of thyroid cancer was 36.6%. The US features with the highest diagnostic odds ratio (DOR) for malignancy were the presence of suspicious lymph nodes (DOR: 56.0 (95% CI: 26.0-119.0)), a 'taller than wide' shape of the nodule (6.0 (95% CI: 2.0-16.0)), the presence of microcalcifications (13.0 (95% CI: 6.0-29.0)) and irregular margins (9.0 (95% CI: 5.0-17.0)). Heterogeneity among the studies was substantial.

Conclusions

Following the diagnosis of a thyroid nodule in the transition age, a thorough US examination of the neck is warranted. The detection of suspicious lymph nodes and/or thyroid nodules with a 'taller than wide' shape, microcalcifications, and irregular margins is associated with the highest risk of malignancy in the selection of nodules candidates for biopsy.

Mutational analysis using next generation sequencing in pediatric thyroid cancer reveals BRAF and fusion oncogenes are common

BACKGROUND

We previously described mutation rates of BRAF^V600E, RAS, RET-PTC and PAX8-PPARγ in pediatric subjects with well-differentiated thyroid cancer (WDTC). We expanded the cohort adding next-generation sequencing (NGS) and assessed genotype-phenotype correlations.

METHODS

Single-center retrospective cohort examining thyroidectomy tissue blocks from consecutive pediatric WDTC patients between 2001 and 2015. Tissues were analyzed at Quest Diagnostics for BRAF, RAS mutations, RET-PTC and PAX8-PPARγ, and additional fusions, using standalone and NGS tests. WDTC included papillary (PTC), follicular (FTC) and follicular-variant PTC (FVPTC).

RESULTS

We genotyped 46 samples (36 females). Mean age at diagnosis was 14.7 years and the cohort comprised of mostly Hispanic (60.9%) and Caucasian (26.1%) patients. Mean follow-up was 3.5 years. Genetic alterations (GA) were noted in 69.6%, with BRAF^V600E (n = 11), and RET-PTC (n = 8) detected only in PTC. GA were detected in 2/7 FTC (1 PAX8-PPARγ, 1 NRAS) and 6/10 FVPTC (3 PAX8-PPARγ, 1 STRN-ALK, 1 BRAF^K601E, 1 NRAS). Patients with BRAF^V600E were predominantly Hispanic (81.8%) and >15 years (81.8%), whereas 87.5% RET-PTC and 50% other-fusions occurred in patients ≤15 years (p = 0.044). Of the 29 PTC patients, 82.8% had GA: BRAF^V600E (37.9%), RET-PTC (27.6%), 17.2% other fusion-oncogenes (2 -ALK, 3 -NTRK). Non-RET fusions had the highest vascular invasion (100%, p = 0.042 vs RET-PTC) and frequent lymphatic invasion (80%). GA were most common in PTC with cervical metastasis.

CONCLUSIONS

BRAF^V600E was the most common single mutation, especially in older and Hispanic adolescents. All fusions combined are more common than BRAF^V600E. NGS reveals a genetic basis in most pediatric WDTC, which may have implications for the role of molecular testing and systemic therapy.

Factors Affecting the Nuclei in Newborn and Children

It is known that children are more sensitive to the effects of medical treatments and environment than adults. Today there is limited information regarding the differences in genotoxic effects in children. The micronucleus assay is a method that is used to monitor genotoxicity, and it was validated several years before. Today there is international interest for exfoliated buccal cells. Most of the micronuclei studies in children have been performed with the analyses of lymphocytes. However, there is vast interest in using exfoliated cells from the oral cavity. The reason is that other type of cells are acquired non-invasively, this is an important issue in paediatric cohorts. Unfortunately a limitation of measuring micronuclei frequency is that it has been observed to be low in newborns and on the other hand there are a large number of patients and cell sample counts. It has been observed that radiation exposure and environmental pollutants increase the micronuclei frequency in newborn and children. Regarding the medical treatments, there is little data and several studies are needed to optimise the doses. There is the need to observe if there is a relationship between micronuclei in lymphocytes and exfoliated cells and to identify the baseline of the micronuclei levels. Moreover, we evaluate the changes in response to the toxic agents. Prospective cohorts studies will clarify the predictive value of micronuclei for cancer and chronic diseases for both children and adults. Novel molecular technologies will assist in the elucidation of different biological pathways and molecular mechanisms connected with the micronulcei levels in newborn and children.

Evaluation of the efficacy of EU-TIRADS and ACR-TIRADS in risk stratification of pediatric patients with thyroid nodules

BACKGROUND

Pediatric thyroid nodules have a lower prevalence but a higher rate of malignancy (ROM) than those in adults. Ultrasound features suspected of malignancy lead to fine needle aspiration biopsy (FNAB) and subsequent cytological determination, upon which management is decided. Based on the characteristics of ultrasound, to standardize clinician decisions and avoid unnecessary FNAB, the European Thyroid Association and the American Radiology College have established guidelines for Thyroid Imaging, Reporting and Data System (EU-TIRADS and ACR-TIRADS) for ROM stratification of thyroid nodules. The aim of this study is to evaluate the diagnostic performance of ACR-TIRADS and EU-TIRADS in pediatric age.

MATERIALS AND METHODS

Subjects younger than 18 years of age with thyroid nodules greater than 0.5 cm observed in the 2000-2020 period were included.

RESULTS

Data from 200 subjects were collected. The overall ROM was 13%, rising to 26% if nodules with a diameter >1 cm were considered. Patients with a malignant nodule were more likely to have a higher EU-TIRADS score (p=0.03). Missed cancer diagnoses were 26.9%. Using the EU-TIRADS system, 40% of FNABs could have been avoided, while this scoring system would have resulted in FNAB being performed in 12% of cases where the assessment of ultrasound features would not recommend FNAB. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 73.1%, 57.1%, 73.1%, and 50%, respectively. Even considering the ACR-TIRADS, a higher score correlated with a higher ROM (p<0.001). This system missed 6 diagnoses of cancer (23.1%). Using the ACR-TIRADS system, 45.3% of FNABs could have been avoided, while FNAB should have been performed in 12% of cases where it was not recommended by ultrasound characteristics. Sensitivity, specificity, PPV and NPV were 76.9%, 50%, 76.9%, and 42.9%, respectively.

CONCLUSION

The present study confirms the correspondence of the EU-TIRADS and ACR-TIRADS categories with respect to malignancy but indicates not entirely satisfactory performance compared to FNAB alone. However, the use of the two TIRADS systems should be encouraged in multicentre studies to increase their performance and establish paediatric-specific points in the scoring criteria.

Clinical and Molecular Characterizations of Papillary Thyroid Cancer in Children and Young Adults: A Multicenter Retrospective Study

Background: Papillary thyroid carcinoma (PTC) is a rare malignancy in children and young adults (CAYA). It often presents with aggressive disease patterns and advanced stages, which are clinically distinct from those in adult patients. In this study, we sought to characterize and better understand the clinical variants of PTC in CAYA and explore the underlying mechanisms. Methods: CAYA patients (age ≤18 years) diagnosed with PTC between June 2006 and June 2018 were retrospectively recruited from five hospitals. Demographic information, pathological data, and follow-up status were recorded. Tumor samples obtained from 20 children (mean age 15.15 years) and 10 adults (mean age 38.80 years) underwent comprehensive whole transcriptome sequencing. Differentially expressed genes (DEGs), mutational landscape, and immune infiltration were analyzed. Results: A total of 217 CAYA-PTC patients (162 females and 55 males) with an average age of 14.38 ± 3.53 years (range 2-18) were included. Lymph node metastasis (LNM) was observed in 85.71%, of which 57.60% were in the lateral cervical compartment. Disease recurred in 28 of 217 (12.90%) patients with a median follow-up of 4.76 years. Multivariate logistic regression analysis revealed that age, bilateral disease, extrathyroidal extension, and coexisting Hashimoto's thyroiditis (co-HT) were independent risk factors for LNM, while co-HT was the only risk factor for recurrence. Using whole transcriptome sequencing of PTC tissues, we identified 301 DEGs. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses showed that differences in immune mediators played important roles, based on the distributions of mutation frequencies, types, and expression levels between CAYA and adult patients. Based on the integrated data sets, we identified significantly mutated immune genes, cluster of differentiation 24 (CD24), coagulation factor 12 (F12), coagulation factor 5 (F5), integrin subunit alpha 3 (ITGA3), and retinoic acid early transcript 1L (RAET1L), which were then verified by immunohistochemistry. Furthermore, resting mast cells, resting natural killer cells, plasma cells, and regulatory T cells were different in the CAYA-PTC group and correlated with the expression of immune checkpoints. Conclusions: There are considerable variabilities that may contribute to the different clinical presentations between CAYA and adult PTC patients, among which the decrease in protective immune cells may be a factor. Collectively, our results add to the possible biological mechanisms involved in CAYA-PTC.

Predictive factors of malignancy in pediatric patients with thyroid nodules and performance of the Italian classification (SIAPEC 2014) in the outcome of the cytological FNA categories

PURPOSE

The rate of malignancy (ROM) among pediatric studies using the Bethesda System is 39.5% and 41.5% for atypia of undetermined significance/follicular lesion of undetermined significance and for suspected follicular neoplasm, respectively. Data reported on the basis of Bethesda System showed lower ROM in adults with indeterminate nodules (30.5 and 28.9% respectively). Studies on adults based on the Italian Society of Anatomic Pathology and Cytology (SIAPEC) classification, report ROM of 14.2% for TIR3a and 44.6% for TIR3b category, showing greater sensitivity in detecting malignancy. To date, no performance data are available about SIAPEC classification in pediatric age.

METHODS

Retrospective data were collected from 200 pediatric subjects with thyroid nodules in the period 2000-2020.

RESULTS

The distribution of cytological categories after fine needle aspiration biopsy (FNAB) was 7 TIR1, 4 TIR1c, 22 TIR2, 14 TIR3a, 9 TIR3b, 3 TIR4, and 16 TIR5. The surgical approach was performed in 40/200 subjects, with total ROM of 65% (0% for TIR1-TIR3a, 77.8% for TIR3b, and 100% for TIR4-TIR5). Total FNAB accuracy was 95%, while the sensibility and specificity were 92.3 and 92.6%, respectively.

CONCLUSIONS

The reported data seem to confirm a greater sensitivity of SIAPEC classification to identify malignancy within the indeterminate category also in pediatric age and not only in adulthood. This finding may orient clinicians toward clinical follow-up for the indeterminate TIR3a group and toward surgical approach with total thyroidectomy in the indeterminate TIR3b group, although this indication should be confirmed in further national multicenter studies including larger cohorts.

Chronic Lymphocytic Thyroiditis and Aggressiveness of Pediatric Differentiated Thyroid Cancer

OBJECTIVES/HYPOTHESIS

Hashimoto's Thyroiditis (HT) is a common cause of hypothyroidism. Among adults with differentiated thyroid cancer (DTC), HT appears to be associated with less severe disease burden. In the absence of information regarding HT and disease burden among children with DTC, we assessed the relationship between pediatric DTC severity and HT.

STUDY DESIGN

Retrospective cohort.

METHODS

Charts from 90 pediatric patients who underwent surgical removal of DTC from 2002 to 2017 at tertiary-care children's hospital were reviewed. Demographic, clinical, surgical, pathology, and outcome details were compared between patients with and without HT. Consistency among diagnostic modalities of HT was also evaluated.

RESULTS

Median age at presentation was 16.0 years (range 4.2-18.9 years). Twenty-two patients were male (24%). Forty-five patients (50%) had HT based on presence of thyroid autoantibodies and/or surgical pathology findings and 45 patients did not have HT. Patients with HT had increased odds of microcalcifications (odds ratio [OR]: 3.01, P = .031) and decreased odds of palpable nodules (OR: 0.212, P = .024) and T2 lesions (vs. T1) (OR: 0.261, P = .015) compared with non-HT. No significant differences in demographics and the incidence of multifocality, extrathyroidal extension, lymphovascular invasion, lymph node or pulmonary metastases, disease recurrence, or radioactive iodine treatment were found between the two groups. Thyroglobulin/thyroid peroxidase autoantibodies and surgical pathology indicative of HT were concordant in 82.4% (κ = 0.635, P < .001).

CONCLUSION

HT was present in 50% of children with DTC. Patients with DTC and HT presented with smaller tumors compared to non-HT patients. No significant differences in other markers of disease aggressiveness were found between the two groups.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

Thyroid nodules in childhood-onset Hashimoto's thyroiditis: Frequency, risk factors, follow-up course and genetic alterations of thyroid cancer

OBJECTIVE

We evaluated the frequency, risk factors and the follow-up outcomes of thyroid nodules, and genetic alterations in thyroid cancer, in youth with childhood-onset Hashimoto thyroiditis (HT) residing in an iodine-sufficient country.

DESIGN

A retrospective cohort study.

PATIENTS AND MEASUREMENTS

A total of 213 patients (194 females, mean age 10.6 years at the time of HT diagnosis) were ultrasonographically evaluated. Thyroid nodules were categorized using the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) and the American College of Radiology Thyroid Imaging Reporting and Data System (ACR-TI-RADS).

RESULTS

Thyroid nodules were detected in 40 (18.8%) patients over a median follow-up period of 3.4 years, usually after the onset of puberty. A family history of thyroid disease (hazard ratio 2.1, p = .031) was predictive of thyroid nodule detection. Papillary thyroid carcinoma (PTC) was diagnosed in 9 (4.2% of all and 22.5% of nodule-positive patients). The malignant nodules had a higher K-TIRADS or ACR-TI-RADS risk level compared with benign nodules (p < .01 for both). Genetic alterations were revealed in 7 (BRAF^V600E in 6 and RET-ERC1 fusion in 1) of the eight available tumour tissue samples. None showed evidence of disease over a median follow-up period of 3.4 years.

CONCLUSIONS

The nodule detection rate was 18.8%, with a 22.5% risk of malignancy among the detected nodules in childhood-onset HT patients, showing increased risk in those with a family history. Additional large-scale studies are required to evaluate the usefulness of K-TIRADS or ACR-TI-RADS risk level for the differentiation of paediatric thyroid nodules.

Evaluation of Children and Adolescents with Thyroid Nodules: A Single Center Experience

OBJECTIVE

We aimed to evaluate the clinical, radiological and pathological findings of children and adolescents with thyroid nodules.

METHODS

Data of 121 children and adolescent with thyroid nodules and had fine needle aspiration (FNA) were examined retrospectively. Concomitant thyroid disease, ultrasonography (US) features of the nodule, FNA and histopathological results were recorded. FNA results were assessed according to The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC).

RESULTS

Median (range) age of the cases was 14 (3-18) years and 81% were female. FNA results of patients were: insufficient in 1 (0.8%); benign in 68 (56.2%); indeterminate in 44 (36.4%); and malignant in 8 (6.6%) patients. Among 39 patients who underwent surgery, 10 (25.6%) had differentiated thyroid cancer (DTC) and the overall malignancy rate was 10.0% (10/100). Follow-up FNA results showed progress based on TBSRTC in 18.7% of benign results and 4/75 patients had DTC on surgical excision. Two of 22 patients with atypia of undetermined significance (AUS) who continued follow-up was diagnosed with DTC. Male gender, presence of Hashimoto thyroiditis and US findings of uninodularity, hypoechogenicity, increased blood flow, irregular margins, solid structure, microcalcification and presence of abnormal cervical lymph nodes were associated with malignancy.

CONCLUSION

In this study 10% of thyroid nodules were malignant in children and adolescents. Patients with AUS have a 9% potential for malignancy. Patients with initially benign FNA result may have changes on repeat FNA when assessed with TBSTRC indicating a 5.3% false negative rate.

Development and validation of a population-based model for predicting the regional lymph node metastasis in adolescent differentiated thyroid carcinoma

BACKGROUND

Adolescent differentiated thyroid carcinoma (DTC) is a rare type of thyroid cancer that represents a special entity of all endocrine-related cancer. This study aims to establish the first nomogram for predicting the regional (central and lateral) lymph node metastasis (LNM) in the adolescent population for better surgical management.

METHOD

We retrospectively reviewed the clinicopathology characteristics of adolescent patients with DTC in the Surveillance, Epidemiology, and End Results database between 2010 and 2015.

RESULTS

A total of 1,930 adolescent patients between the ages of 10 and 24 years from the SEER database were enrolled in this study. Six predictive factors including age, race, histology, multifocality, extrathyroidal invasion (EI) and tumor size were identified to be significantly associated with the regional LNM via univariate and multivariate logistic regression analyses. These indicators were used to construct a nomogram for predicting the regional LNM in adolescent patients with DTC. Moreover, a satisfied predictive ability of the model was determined with a C-index of 0.794, supported by an internal validation group with a C-index of 0.776. The Decision Curve Analysis and calibration curve further conducted a great agreement in our model.

CONCLUSION

The first predictive model containing multiple factors has been successfully established with good discrimination for predicting the regional LNM in adolescent patients with DTC. This nomogram could effectively help surgeons to make better individualized surgical decision intraoperatively, especially in terms of whether cervical lymph node dissection (LND) is warranted.

Increasing incidence and survival of paediatric and adolescent thyroid cancer in Cyprus 1998-2017: A population-based study from the Cyprus Pediatric Oncology Registry

BACKGROUND

Paediatric and adolescent thyroid cancer incidence rates are increasing in many countries. We determined incidence rates, temporal trends and survival from thyroid cancer diagnosed in childhood and adolescence in Cyprus during 1998-2017.

METHODS

Patients aged 0-19 years, diagnosed with thyroid cancer in the Pediatric Oncology Registry of Cyprus were included. Crude incidence rates, age standardized rates, time trends and overall survival were analysed. Annual rates and temporal trends were calculated using Microsoft Excel 2016 and Joinpoint regression analysis.

RESULTS

Eighty-one cases (76.5 % female, 23.5 % male) were identified. The crude rates (per 100,000 persons) were for both sexes 2.00 (95 % CI 1.61, 2.49), females 3.15 (95 % CI 2.45, 4.03) and males 0.92 (95 % CI 0.58, 1.44). The annual percentage changes of crude and standardised rates were 7.5 % (p < 0.05) and 7.6 % (p < 0.05). The annual percentage changes of crude rates were for females 5.1 % (p = 0.1), males 8.4 % (p < 0.05) and 15-19-year-olds 7.6 % (p < 0.05). The female to male rate ratio was 3.42 (95 % CI 2.06, 5.74). Papillary thyroid carcinoma represented 86.4 % of all cases. There was only one case after previous cancer therapy. The rate ratio of 2nd (2008-2017) to 1st (1998-2007) periods for metastatic (regional) stages was 3.76 (95 % CI 1.74, 8.31). Survival until 2018 was 100 %.

CONCLUSION

This population-based study demonstrated that thyroid cancer incidence rates in 0-19-year-olds in Cyprus was among the world's highest. Increasing trends mainly affected males and females aged 15-19 years with papillary thyroid carcinoma, the dominant type. Cases after previous cancer therapy didn't contribute to increasing rates. The increase of metastatic cases suggests a true increase of thyroid cancer rather than overdiagnosis. Although prognosis is excellent with 100 % survival, the rising incidence rate is unexplained, indicating the need to identify causes.

Papillary thyroid carcinoma in children with Hashimoto's thyroiditis - a review of the literature between 2000 and 2020

OBJECTIVES

Thyroid cancer is the most common pediatric endocrine neoplasm representing 3% of all malignancies in children. Hashimoto's thyroiditis (HT) is also a common disorder in the pediatric age range. Patients with HT frequently develop enlarged thyroid with nodules. We aimed to provide a literature review on the frequency of papillary thyroid carcinoma (PTC) in patients with HT.

CONTENT

A literature search of the PubMed database between 2000 and 2020 was performed, using the relevant keywords "papillary thyroid carcinoma," "Hashimoto's thyroiditis" and "children". We followed the PRISMA statement guidelines during the preparation of this review. Six studies (n=2,065 patients with HT) were retained for the final analysis. The follow-up of the patients with HT was from 2 to 10 years. PTC was diagnosed in 0.67-7.87% of the HT patients included in these studies. In patients with HT and nodules, the percentage of PTC varied between 5.13 and 35%. The overall occurrence of PTC in patients with HT was 3.07%.

SUMMARY AND OUTLOOK

The number of patients developing thyroid nodules in relation to HT was increased. The development of PTC in children with HT appeared to be higher than in the normal population.

Autoimmune hyperthyroidism in children & adolescents in Sudan: a 13 years' experience of a Paediatric Endocrinology Clinic

Background Little has been published about hyperthyroidism in children from Sudan or Africa. In limited resource countries, lack of facilities and sociocultural factors might make international diagnosis and management guidelines difficult to follow. We aimed to determine the magnitude of autoimmune hyperthyroidism, clinical presentation, diagnosis, management and its outcome in Sudan. Method Records of all patients diagnosed as Graves' disease (GD) or Hashitoxicosis (HTx) were reviewed and missing data filled by interviewing patients and/or their families. Data including age, sex, clinical presentation, investigations, management and outcome were obtained. Results Eighty-eight patients, 80 with GD (F:M = 4.7:1) and 8 with HTx (F:M = 7:1), were diagnosed at 11.8 ± 3.05 and 11.23 ± 2.78 years, respectively (p = 0.52). GD patients were diagnosed based on presence of exophthalmos (66.25%), positive thyroid receptor autoantibodies (12.5%), prolonged illness duration (8.75%) or remission failure to only B blocker (16.25%). All GD patients were started on carbimazole and cumulative remission rate was 11.8%, 32.4% and 41.2% by end of the second, third and fourth year respectively, however it plateaus after that. While 12 GD patients underwent surgery, only three opted for radioiodine ablation. Conclusion Hyperthyroidism is not an uncommon problem. In absence of laboratory facilities, differentiation between GD and HTx can be made based on clinical grounds. Continuation of medical treatment for 4 years can increase the remission rate to 41.2%. In Sudan, surgery is the preferred method of definitive therapy.

Clinical features may help to identify children and adolescents with greatest risk for thyroid nodules

BACKGROUND

Thyroid nodules (TN) are detected in a small number of asymptomatic children and adolescents but are more frequently malignant (22-26%) than in adults leading some clinicians to perform thyroid ultrasound (US) for all children with goiter or autoimmune thyroiditis (AIT). Our study was designed to determine if suspicious clinical features predict the presence of TN in children with goiter or AIT so that US could be performed on those at highest risk.

METHODS

This was a retrospective review of 223 children and adolescents with goiter or AIT evaluated at a single institution. US was not performed on all patients. It is our practice to define glands that are large, firm, or nodular to palpation as "suspicious". Suspicious glands were interrogated by US and if TN was confirmed, this was further evaluated by fine-needle aspiration followed by surgery if indicated.

RESULTS

The median age was 12.9 years with 74.4% female. TN were confirmed by US in 16.6% of all patients but only 4.8% of those with AIT. By univariate analysis, TN were more common in those with family history of TN or differentiated thyroid carcinoma (DTC), thyroid asymmetry, and lower thyrotropin (TSH) levels. Differentiated thyroid carcinoma (DTC) was identified in 10.8% of TN and 1.8% of all patients. Firmness was significantly more common in patients with DTC (p = 0.0013).

CONCLUSION

TN were less common in those with AIT than reported in previous studies, suggesting that clinical features might fail to identify the majority of TN in patients with AIT. However, patients with asymmetric thyroid and a family history of TN or DTC have greatest risk for TN.

Long-term ultrasound follow-up of intrathyroidal ectopic thymus in children

OBJECTIVE

To present the sonographic follow-up of intrathyroidal ectopic thymus (IET) in children and adolescent patients.

PATIENTS

Out of the 507 children referred to FNAB between 2006 and 2018, 30 (5.9%) pediatric patients (10 females), mean age 5.7 years (1.2-13.8, median 4.9 years) were diagnosed with IET.

METHODS

A retrospective analysis of medical files of patients diagnosed with IET between 2006 and 2018. Assessed data included ultrasound characterisation, elastographic strain ratio (SR) results and hormonal evaluation.

RESULTS

Analysis of thyroid US scans revealed that the mean age at the first thyroid ultrasound was 5.7 (1.2-13.8, median 4.9) years, and at the last US 10.7 (3.7-18, median 10.5) years. The mean time of the IET observation was 59.6 (2-148, median 53.5) months. On US, IET was hypoechoic with multiple linear and punctate echoes, hypovascular, fusiform on longitudinal plane and round or polygonal on an axial plane, more common in the right thyroid lobe (66.7%) and located in the posterior part of the lobes (54.5%), bilateral in two patients and multifocal in one patient. SR of IET was similar to the surrounding normal thyroid tissue. Complete regression of IET was observed in 12/30 patients after a mean time of 81.7 months (median 76.5), at the mean age of 13.7 (9.2-18, median 13.9) years. FNAB was performed in 10/30 and a hemithyroidectomy in 1/30 IET patients. In the FNAB (+) group, patients were younger (5.08 vs 6.08 years) and lesions were larger (0.12 ml vs 0.05 ml) than in the FNAB (-) group. All patients with IET were euthyroid with negative TPOAb and TgAb levels.

CONCLUSION

The reproducibility of unique ultrasound features of IETs allows for safe long-term follow-up of these benign lesions in the majority of pediatric patients: not only monitoring the regression of IET but also screening towards the rare occurrence of a tumor arising from the IET.

Thyroid Cancer in the Pediatric Population

Thyroid cancer is rare in the pediatric population, but thyroid carcinomas occurring in children carry a unique set of clinical, pathologic, and molecular characteristics. In comparison to adults, children more often present with aggressive, advanced stage disease. This is at least in part due to the underlying biologic and molecular differences between pediatric and adult thyroid cancer. Specifically, papillary thyroid carcinoma (which accounts for approximately 90% of pediatric thyroid cancer) has a high rate of gene fusions which influence the histologic subtypes encountered in pediatric thyroid tumors, are associated with more extensive extrathyroidal disease, and offer unique options for targeted medical therapies. Differences are also seen in pediatric follicular thyroid cancer, although there are few studies of non-papillary pediatric thyroid tumors published in the literature due to their rarity, and in medullary carcinoma, which is most frequently diagnosed in the pediatric population in the setting of prophylactic thyroidectomies for known multiple endocrine neoplasia syndromes. The overall shift in the spectrum of histotypes and underlying molecular alterations common in pediatric thyroid cancer is important to recognize as it may directly influence diagnostic test selection and therapeutic recommendations.

Thyrotropin serum levels and coexistence with Hashimoto's thyroiditis as predictors of malignancy in children with thyroid nodules

Thyroid cancer (TC) in childhood is a rare disease characterized by an excellent prognosis. Thyroid nodules in children, although less common than in adults, have a greater risk of malignancies, particularly in those cases associated with anamnestic, clinical and ultrasonographic risk factors.

Among the factors, which have been found to be linked with an increased relative risk of TC in children, an important role seems to be possibly played by an underlying nodular Hashimoto’s thyroiditis (HT) and by the serum levels of TSH.

Aim of this Commentary was to specifically address this last point.

According to the available pediatric literature on the relationships between these risk factors and phenotypical expression of TC in children, it is possible to conclude that: 1) It is not completely clarified if HT per se predisposes to malignancy or if it represents an incidental histologic finding in cases with TC or if it may be the result of an immune response against tumoral cells. 2) It is unclear whether phenotypic expression of TC is more severe in the cases with associated HT but normal TSH serum levels. 3) Persistently elevated TSH levels play an independent role as predictors of the likelihood of TC, especially in children but also in adults. 4) Patients with nodular HT and subclinical hypothyroidism need to be treated with Levothyroxine in order to prevent the development of both TC and severe thyroid dysfunctions.

Follow-up of parenchymal changes in the thyroid gland with diffuse autoimmune thyroiditis in children prior to the development of papillary thyroid carcinoma

PURPOSE

To present the outcomes of ultrasound (US) follow-ups in children with autoimmune thyroid disease who did not have a thyroid nodule on admission but developed papillary thyroid carcinoma (PTC) and to characterize the parenchymal changes in the thyroid gland prior to the development of PTC.

METHODS

A retrospective thyroid US scan review of 327 patients diagnosed with AIT was performed. Forty patients (40/327, 12.2%) presented nodular AIT variant with a normoechogenic background. Eleven patients (11/327, 3.4%, 11/40, 27.5%) presenting this variant were diagnosed with PTC (nine females-mean age 15.3 years; two males aged 11 and 13 years). In five of 11 patients, the suspicious nodule that was later confirmed to be PTC was detected on the initial US at presentation. For the remaining six females (6/11) who developed PTC during the follow-up, we retrospectively analysed their US thyroid scans and these patients were selected for analysis in this study.

RESULTS

On admission, the US evaluation revealed an enlarged normoechogenic thyroid gland in three patients and a hypoechogenic thyroid gland with fibrosis as indicated by irregular, chaotic hyperechogenic layers in three patients. No thyroid nodules were identified. Ultrasound monitoring revealed increasing echogenicity of the thyroid parenchyma during the follow-up. PTC developed in a mean time of 4.6 years (1 9/12-7 4/12 years) since referral to the outpatient thyroid clinic and 2.9 years (6/12-6 9/12) since the last nodule-free US thyroid scan.

CONCLUSIONS

Sonographic follow-up assessments warrant further exploration as a strategy to determine PTC susceptibility in the paediatric population.

Influence of Hashimoto Thyroiditis on the Development of Thyroid Nodules and Cancer in Children and Adolescents

It is unclear whether patients with Hashimoto thyroiditis (HT) are predisposed to develop thyroid nodules and/or thyroid cancer. The objective of our study was therefore to assess the prevalence of thyroid nodules and/or cancer in patients with HT and to look for possible prognostic factors. A retrospective survey of 904 children/adolescents with HT (709 females, 195 males) regularly followed in nine Italian centers of pediatric endocrinology was performed. Median period of follow-up was 4.5 years (1.2 to 12.8 years). We evaluated free T4, TSH, thyroid peroxidase antibody (TPOAb), thyroglobulin antibodies, and thyroid ultrasound yearly. One hundred seventy-four nodules were detected, with an annual incidence rate of 3.5%. Ten nodules were malignant (8 papillary and 2 papillary follicular variant), giving a 5.7% prevalence of cancer among patients with nodules. The severity of hypoechogenity at ultrasound, TPOAb, and free T4 serum concentrations were predictive for the appearance of new nodules. Furthermore, a positive correlation was observed between TPOAb titer and the development of thyroid cancer. In conclusion, HT seems to influence the development of thyroid nodules, but not cancer in children and adolescents.

Diagnostic accuracy of the McGill thyroid nodule score in paediatric patients

INTRODUCTION

Thyroid cancer is the most common paediatric endocrine cancer; accurate diagnosis and prompt management of paediatric thyroid nodules is critical. The McGill Thyroid Nodule Score (MTNS), based upon clinical, ultrasound (US) and cytology criteria, has recently been modified and studied in a pilot paediatric group with good results. We aim to describe the diagnostic accuracy of the paediatric modified MTNS (PMTNS) in a large paediatric cohort.

METHODS

We utilized an established retrospective cohort between 1996 and 2015 of 99 patients ≤21 years old with 131 thyroid nodules. Two experienced paediatric radiologists, blinded to pathology and radiology reports, reviewed US features. We abstracted cytology, histology and laboratory results, assigning each nodule a PMTNS. PMTNS performance was compared to FNA and histology.

RESULTS

Approximately 33% of nodules were malignant. The cohort was predominantly adolescent (mean age 15.4 ± 3.8 years). The average PMTNS for malignant and benign nodules, based on final histology, was 12.7 ± 4.3 and 1.7 ± 2.9, respectively. A PMTNS ≥8 resulted in a 93.2% sensitivity and 93.1% specificity for detecting malignancy, while a PMTNS ≥9 resulted in a 90.9% sensitivity and 96.6% specificity. However, Bethesda cytology category ≥4 independently had a 97.7% sensitivity and 94.0% specificity for detecting malignancy. The PMTNS had diminishing diagnostic accuracy in younger children compared with older children.

CONCLUSION

Paediatric modified McGill Thyroid Nodule Score predicts malignancy, perhaps due to the score's emphasis on cytology results; however, the score is less accurate in younger patients. While cytology results remain reliable, further work is needed to develop a non-invasive scoring system to predict malignancy in children.

Subclinical Hypothyroidism in Children: When a Replacement Hormonal Treatment Might Be Advisable

Aim of this mini review was to analyze the main variables which should be taken into account when the decision regarding a possible treatment with L-T4 has to be considered for a child with subclinical hypothyroidism (SH). The indications of periodical monitoring and vigilance have been also discussed. It was inferred that therapy should be recommended for children with underlying Hashimoto's thyroiditis and progressive deterioration of thyroid status over time, particularly in the cases with goiter and hypothyroid symptoms and in those with associated Turner syndrome or Down's syndrome and/or other autoimmune diseases. Treatment might also be recommended for children with proatherogenic metabolic abnormalities. Treatment is not advisable in children with idiopathic and mild SH, no goiter, no hypothyroid symptoms and negative anti-thyroid autoantibodies. In the absence of any therapeutic intervention, clinical status and thyroid function tests should be periodically monitored, in order to individuate the children who might benefit from treatment. It has been suggested that children with a persistent mild elevation of TSH, who are not treated with L-T4, should undergo biochemical monitoring of thyroid function and re-assessment of clinical status every 6 months. After 2 years with stable thyroid function tests, the interval between monitoring can be extended.

Ultrasound and the Evaluation of Pediatric Thyroid Malignancy: Current Recommendations for Diagnosis and Follow-up

Ultrasound (US) plays a critical role in the evaluation, treatment, screening, and surveillance of thyroid malignancy in pediatric patients. This review aims to summarize recent advances in this topic. Improvements in imaging technology have amplified the advantage of US and US-guided fine-needle aspiration biopsy for thyroid nodule evaluation, cancer diagnosis, and surgical planning. Ultrasound has a definitive screening role for early cancer detection in high-risk patients, including those with a history of radiation exposure from childhood treatments, environmental radiation disasters, or hereditary/familial cancer syndromes. Finally, US is a key component of lifelong surveillance for recurrence among pediatric thyroid cancer survivors.

Thyroid nodules and cancer in children and adolescents affected by Hashimoto's thyroiditis

OBJECTIVE

To investigate the rates of thyroid nodules and cancer in pediatric cases of Hashimoto's thyroiditis (HT) in Korea.

METHODS

We retrospectively reviewed 89 pediatric and adolescent patients (age, 3-18.0 years) with HT who underwent thyroid ultrasonography (US) at our institution from February 2006 to July 2016. The diagnosis of HT was based on the presence of thyroid autoantibodies. The presence of any thyroid nodules with US and cytopathologic features was analyzed. The malignancy rate was also determined.

RESULTS

Thyroid nodules were in 20 of the 89 patients (22.4%). Eight of these 20 patients (40%) had colloid cysts, two (10%) had nodular hyperplasia, one (5%) had follicular adenoma, and two (10%) had lymphocytic thyroiditis. Seven of the 89 patients (7.9%) were confirmed to have a malignancy, all of which were papillary thyroid carcinoma (PTC); of those, five patients had diffuse sclerosing variant PTC, and two had conventional PTC on pathology.

CONCLUSION

The prevalence of thyroid nodules in children and adolescents with HT was 22.4%. The malignancy rate of children with HT was 7.9%. The malignancy rate among thyroid nodules was 35%, which is higher than the 26% rate generally reported for children with nodules. Therefore, using thyroid US to survey known or suspected thyroid nodules might be helpful in children and adolescents with HT and may provide further useful diagnostic information. Advances in knowledge: Thyroid US could help to assess HT patients who have known or suspected thyroid nodules.

Ultrasound variants of autoimmune thyroiditis in children and adolescents and their clinical implication in relation to papillary thyroid carcinoma development

BACKGROUND

The prevalence of autoimmune thyroiditis (AIT) and papillary thyroid carcinoma (PTC) is rising in children and adolescents, and the coincidence of AIT and PTC is as high as 6.3-43%.

OBJECTIVE

To investigate the ultrasound manifestation of AIT in relation to PTC development in paediatric patients.

PATIENTS

179 paediatric patients (133 females), mean (SD) age: 13.9 (3.03) years diagnosed with AIT and referred for ultrasound evaluation. Eight patients were diagnosed with PTC (6 females).

METHODS

Retrospective analysis of thyroid ultrasound scans of patients diagnosed with AIT. Thyroid and autoimmune status was assessed based on TSH, fT4, fT3 and increased aTPO and/or aTG and/or TRAB levels. In patients with PTC, total thyroidectomy was performed.

RESULTS

Analysis of thyroid US scans revealed that the following five ultrasound variants of AIT were observed in 179 patients: the most common in 35.2%-diffuse thyroiditis with hypoechogenic background and normoechogenic parenchyma, in 30.2%-diffuse thyroiditis with irregular background, in 18.9% nodular variant with normoechogenic background, in 11.7%-micronodulations and in 3.9%-diffuse hypoechogenic background. Eight cases of PTC were diagnosed in nodular variant of AIT with normoechogenic irregular background.

CONCLUSION

Patients with AIT and nodular variant with normoechogenic irregular background of the thyroid gland on US scans are in the risk group of developing PTC and should be followed up with regular neck US assessment.

Differentiated thyroid carcinoma presentation may be more aggressive in children and adolescents than in young adults

Background

The available studies concerning the influence of age on the phenotypical expression of differentiated thyroid carcinoma (DTC) have hitherto compared DTC presentation either between pre-pubertal and pubertal children or between pediatric patients and aged adults; aim of this study was to ascertain for the first time whether presentation of DTC may significantly vary according to age, even within a peculiar study population covering only young patients aged less than 30 years.

Methods

The main clinical, biochemical and pathologic data at DTC diagnosis were retrospectively recorded in 2 selected cohorts including, respectively, 18 children and adolescents aged less than 18 years (Group A) or 45 young adults aged between 20 and 29.8 years (Group B).

Results

The statistical distribution of DTC cases in the different age ranges was found to progressively increase with increasing age; furthermore, the patients of Group A exhibited at diagnosis a more severe clinical involvement and a higher rate of extra-regional metastases; finally, also the association with both autoimmune thyroid diseases (AITDs) and a biochemical hypothyroid pattern was more common in Group A patients.

Conclusions

In a study population younger than 30 years: a) the risk of developing DTC increases with age, achieving its zenith during the 3rd decade of life; b) clinical presentation is more severe in children and adolescents younger than 18 years than in the patients aged between 20 and 30; c) in the cohort of children and adolescents DTC is more often associated with AITDs, which might play some role in conditioning the more aggressive phenotypical presentation of DTC in this patient group.

Hashimoto's Disease and Thyroid Cancer in Children: Are They Associated?

Hashimoto's thyroiditis (HT) is the most common cause of thyroid disease in children and adolescents. Along with significant modifications of thyroid function, HT in pediatric age can be accompanied by relevant thyroid structural alterations. Over time, benign thyroid nodules, carcinoma and, rarely, primary non-Hodgkin lymphoma can develop. However, the relationships between HT and neoplasms are poorly defined. The main aim of this paper is to discuss what is presently known regarding the coexistence of HT and thyroid tumors. Moreover, we attempt to define the pathogenesis of cancer development in children with HT. Literature analysis showed that despite its rarity and relatively promising prognosis, thyroid cancer is associated with HT. Although not all reasons for the coexistence of these diseases are clearly defined, children with HT should be considered at higher risk for thyroid cancer development. Strict correlations between high levels of serum TSH and anti-thyroid antibodies with cancer must be remembered. The same is true for the presence of nodules, especially if multiple nodules are present and ultrasonography and thyroid fine needle aspiration cytology should be promptly used in uncertain cases.

BRAFV600E mutation contributes papillary thyroid carcinoma and Hashimoto thyroiditis with resistance to thyroid hormone: A case report and literature review

Resistance to thyroid hormone (RTH) is a rare autosomal hereditary disorder characterized by increased serum thyroid hormone (TH) levels with unsuppressed or increased thyrotropin concentration. It remains unknown whether the coexistence of RTH with papillary thyroid carcinoma (PTC) and Hashimoto thyroiditis (HT) is incidental or whether it possesses a genetic or pathophysiological association. In the present study, a case of RTH with PTC and HT in an 11-year-old Chinese patient was examined and the clinical presentation of RTH with PTC was discussed. In addition, the possible associations between RTH, PTC and HT were determined. HT was confirmed in the patient using an autoimmune assay and thyroid ultrasound. RTH was diagnosed on the basis of clinical manifestations, laboratory information and gene analysis, and PTC was diagnosed according to histological results. Results of BRAF^V600E mutation analysis were positive. A literature review of 14 cases of RTH with PTC was included for comparison. The present case report indicates an association of RTH with PTC and HT coexistence in the patient. Close follow-up, histological evaluation and BRAF^V600E mutation detection should be performed in each RTH case with HT, since a persistent increase in TSH may be a risk factor for the development of thyroid neoplasm.

The autoimmune burden in juvenile idiopathic arthritis

Background

Juvenile idiopathic arthritis (JIA) is a chronic inflammatory arthritis of unknown origin which can be considered an autoimmune disease (AD). The aim of this study is to analyse the presence of two or more autoimmune diseases (polyautoimmunity) in patients suffering from JIA and to evaluate the occurrence of ADs in their families.

Methods

Seventy-nine patients diagnosed with JIA aged 0–21 years, admitted to the Paediatric Rheumatology Unit, Sant’Orsola-Malpighi Hospital, Bologna were screened for ADs. Parents were asked about the presence of ADs in the living relatives of first and second degree.

Results

Twelve of 79 patients (15.2%) had at least 1 AD associated with JIA. Eight patients (10.1%) suffered from autoimmune thyroid disease (AITD), three patients had celiac disease, three patients suffered from psoriasis, one from alopecia and 1 from insulin-dependent diabetes mellitus. The average age at diagnosis was 13.2 years and the cumulative incidence of AITD was 36%. Seventy-six families were studied for a total of 438 relatives. The prevalence of ADs was 13%, greater in first-degree relatives (16.7%) than in second-degree ones (11.1%). The most common AD was AITD; there was no difference in JIA’s age of presentation between patients with positive and negative familiarity with ADs (p > 0.05).

Conclusion

Children and adolescents with JIA present a high autoimmunity burden, most commonly represented by AITD. Familial autoimmunity is not negligible in patients suffering from JIA (almost 50% of patients have at least one relative with an AD) and it should always be carefully examined.

Nuclear Medicine in Pediatric and Adolescent Tumors

Nuclear medicine has an important role in the management of many cancers in pediatric age group with multiple imaging modalities and radiopharmaceuticals targeting various biological uptake mechanisms. 18-Flourodeoxyglucose is the radiotracer of choice especially in patients with sarcoma and lymphoma. (18)FDG-PET, for sarcoma and lymphomas, is proved to be superior to conventional imaging in staging and therapy response. Although studies are limited in pediatric population, (18)FDG-PET/CT has found its way through international guidelines. Limitations and strengths of PET imaging must be noticed before adapting PET imaging in clinical protocols. Established new response criteria using multiple parameters derived from (18)FDG-PET would increase the accuracy and repeatability of response evaluation. Current data suggest that I-123 metaiodobenzylguanidine (MIBG) remains the tracer of choice in the evaluation of neuroblastoma (NB) because of its high sensitivity, specificity, diagnostic accuracy, and prognostic value. It is valuable in determining the response to therapy, surveillance for disease recurrence, and in selecting patients for I-131 therapy. SPECT/CT improves the diagnostic accuracy and the interpretation confidence of MIBG scans. (18)FDG-PET/CT is an important complementary to MIBG imaging despite its lack of specificity to NB. It is valuable in cases of negative or inconclusive MIBG scans and when MIBG findings underestimate the disease status as determined from clinical and radiological findings. F-18 DOPA is promising tracer that reflects catecholamine metabolism and is both sensitive and specific. F-18 DOPA scintigraphy provides the advantages of PET/CT imaging with early and short imaging times, high spatial resolution, inherent morphologic correlation with CT, and quantitation. Regulatory and production issues currently limit the tracer's availability. PET/CT with Ga-68 DOTA appears to be useful in NB imaging and may have a unique role in selecting patients for peptide receptor radionuclide therapy with somatostatin analogues. C-11 hydroxyephedrine PET/CT is a specific PET tracer for NB, but the C-11 label that requires an on-site cyclotron production and the high physiologic uptake in the liver and kidneys limit its use. I-124 MIBG is useful for I-131 MIBG pretherapeutic dosimetry planning. Its use for diagnostic imaging as well as the use of F-18 labeled MIBG analogues is currently experimental. PET/MR imaging is emerging and is likely to become an important tool in the evaluation. It provides metabolic and superior morphological data in one imaging session, expediting the diagnosis and lowering the radiation exposure. Radioactive iodines not only detect residual tissue and metastatic disease but also are used in the treatment of differentiated thyroid cancer. However, these are not well documented in pediatric age group like adult patients. Use of radioactivity in pediatric population is very important and strictly controlled because of the possibility of secondary malignities; therefore, management of oncological cases requires detailed literature knowledge. This article aims to review the literature on the use of radionuclide imaging and therapy in pediatric population with thyroid cancer, sarcomas, lymphoma, and NB.

Thyroid function in children and adolescents with Hashimoto's thyroiditis after l-thyroxine discontinuation

OBJECTIVE

Thyroid function may recover in patients with Hashimoto's thyroiditis (HT).

DESIGN

To investigate thyroid function and the need to resume l-thyroxine treatment after its discontinuation.

SETTING

Nine Italian pediatric endocrinology centers.

PATIENTS

148 children and adolescents (25 m and 123 f) with HT on treatment with l-thyroxine for at least one year.

INTERVENTION AND MAIN OUTCOME MEASURE

Treatment was discontinued in all patients, and serum TSH and fT4 concentrations were measured at the time of treatment discontinuation and then after 2, 6, 12 and 24 months. Therapy with l-thyroxine was re-instituted when TSH rose >10 U/L and/or fT4 was below the normal range. The patients were followed up when TSH concentrations were between 5 and 10 U/L and fT4 was in the normal range.

RESULTS

At baseline, TSH was in the normal range in 139 patients, and was between 5 and 10 U/L in 9 patients. Treatment was re-instituted after 2 months in 37 (25.5%) patients, after 6 months in 13 patients (6.99%), after 12 months in 12 patients (8.6%), and after 24 months in an additional 3 patients (3.1%). At 24 months, 34 patients (34.3%) still required no treatment. TSH concentration >10 U/L at the time of diagnosis was the only predictive factor for the deterioration of thyroid function after l-thyroxine discontinuation.

CONCLUSIONS

This study confirms that not all children with HT need life-long therapy with l-thyroxine, and the discontinuation of treatment in patients with a TSH level <10 U/L at the time of diagnosis should be considered.

Autoimmune thyroid diseases in children

Autoimmune thyroid diseases (AIT) are common in children and may present with a variety of signs and symptoms including: euthyroid goiter, hypothyroidism, or hyperthyroidism. The natural history of AIT may be different in children but in all age groups, there appear to be genetic risk factors and environmental triggers that initiate thyroid autoimmunity. Areas covered: In this review, we summarize recent studies that investigate the genetics and environmental triggers believed to be involved in thyroid autoimmunity. We also discuss the approach and controversies in the treatment of children with AIT. Expert commentary: Much has been learned about the major roles for genetics, cytokines, regulatory lymphocytes, and environmental triggers in CLT but controversies remain.

Co-Existence of Thyroid Nodule and Thyroid Cancer in Children and Adolescents with Hashimoto Thyroiditis: A Single-Center Study

BACKGROUND

Currently, there is an inadequate number of studies on nodule and malignancy development in children and adolescents with Hashimoto thyroiditis (HT).

MATERIAL AND METHODS

Patients who were diagnosed with HT between 2004 and 2013 were included in the study. The HT diagnosis was made with a heterogeneous appearance on thyroid ultrasonography and the elevation of antithyroid peroxidase and/or anti-thyroglobulin antibodies. Fine-needle aspiration biopsy (FNAB) was performed in cases with a nodule size >1 cm or who had ultrasonography findings indicating malignancy.

RESULTS

A total of 39 (13%) thyroid nodules were detected in 300 patients with a diagnosis of HT. Papillary thyroid carcinoma (PTC) was diagnosed in 2 of the 12 cases in whom FNAB was performed. The thyroid nodule was detected at the same time as HT in the 2 cases with malignancy. The PTC diagnosis was made 2 years after the HT diagnosis in the first case and 3 years later in the second case. The largest diameter of the thyroid nodule was 5 mm in both cases.

CONCLUSION

The thyroid nodule rate on an HT background was found to be 13%, and the thyroid malignancy rate was 0.67% in our study.

Evaluation and management of thyroid nodules in children

PURPOSE OF REVIEW

The review is focused on new information about the presentation and management of thyroid nodules in children and adolescents.

RECENT FINDINGS

Palpable thyroid nodules are uncommon in children but many children have nodules detected by radiologic imaging. How to evaluate them, when to suspect thyroid cancer, and how best to follow apparently benign nodules has become an area of great interest. The American Thyroid Association recently published treatment guidelines for children with thyroid nodules and cancers but much has been learned since that publication.

SUMMARY

Personal and family history, ultrasound features, and fine needle aspiration cytology are used to determine the risk of cancer in thyroid nodules, which are then managed according to cancer risk.

Thyroid Cancer in Pediatrics

Well differentiated thyroid cancer (DTC) in children is characterized by a high rate of response to treatment and low disease-specific mortality. Treatment of children with DTC has evolved toward a greater reliance on evaluation and monitoring with serial serum thyroglobulin measurements and ultrasound examinations. Radioiodine therapy is recommended for thyroid remnant ablation in high-risk patients, treatment of demonstrated radioiodine-avid local-regional disease not amenable to surgical resection, or distant radioiodine-avid metastatic disease. Sufficient time should be given for benefits of radioiodine therapy to be realized, with follow-up monitoring. Re-treatment with radioiodine can be deferred until progression of significant disease manifests.

Mutational Analysis in Pediatric Thyroid Cancer and Correlations with Age, Ethnicity, and Clinical Presentation

BACKGROUND

Well-differentiated thyroid cancer (WDTC) incidence in pediatrics is rising, most being papillary thyroid carcinoma (PTC). The objective of the study was to assess the prevalence of different mutations in pediatric WDTC and correlate the genotype with the clinical phenotype.

METHODS

This is a single-center retrospective study. Thyroid tissue blocks from 42 consecutive pediatric WDTC patients who underwent thyroidectomy between 2001 and 2013 were analyzed at Quest Diagnostics for BRAF(V600E), RAS mutations (N,K,H), and RET/PTC and PAX8/PPARγ rearrangements, using validated molecular methods. Thyroid carcinomas included PTC, follicular thyroid carcinoma (FTC), and follicular variant of PTC (FVPTC).

RESULTS

Thirty-nine samples (29 females) were genotyped. The mean age at diagnosis was 14.7 years (range 7.9-18.4 years), and most were Hispanic (56.4%) or Caucasian (35.9%). The mean follow-up period was 2.9 years. Mutations were noted in 21/39 (53.8%), with both BRAF(V600E) (n = 9), and RET/PTC (n = 6) detected only in PTC. Mutations were detected in 2/5 FTC (PAX8/PPARγ and NRAS) and 3/6 FVPTC cases (PAX8/PPARγ). Of 28 PTC patients, 57.1% had mutations: 32.1% with BRAF(V600E), 21.4% with RET/PTC, and 3.6% with NRAS. Of patients with BRAF(V600E), 77.8% were Hispanic and 88.9% were >15 years, while all RET/PTC-positive patients were ≤15 years (p = 0.003). Tumor size, lymph node involvement, and distant metastasis at diagnosis (or soon after (131)I ablation) did not vary significantly based on the mutation.

CONCLUSIONS

BRAF(V600E) was the most common mutation, especially in older and Hispanic adolescents. A larger, ethnically diverse pediatric cohort followed long term will enable the genotypic variability, clinical presentation, and response to therapy to be better assessed.

Diagnostic performance of thyroid ultrasonography screening in pediatric patients with a hypothyroid, hyperthyroid or euthyroid goiter

BACKGROUND

Goiter is frequently the first indicator of thyroid disease in children.

OBJECTIVE

To evaluate the usefulness of ultrasonography (US) in the identification of potential malignant nodules and autoimmune thyroiditis in children with diffuse goiter.

MATERIALS AND METHODS

This study consisted of 113 patients <20 years with a diffuse goiter who underwent thyroid US. Parenchymal echogenicity and the presence of nodules and abnormal lymph nodes were evaluated on US; if a thyroid nodule was detected, its characteristics were analyzed. The diagnostic accuracy of the US findings in the diagnosis of autoimmune thyroid disease was assessed.

RESULTS

Thyroid nodules were detected on US in 72 of the 113 (63.7%) patients. Of these, 65 (90.3%) had probably benign nodules and 4 (5.6%) patients had nodules suspicious of malignancy. The remaining had indeterminate nodules only. In one child with suspected malignant nodules, papillary thyroid cancer with coexisting autoimmune thyroiditis was confirmed. Hypoechogenicity was visualized in 23 (88.5%) patients with autoimmune thyroiditis and 12 (85.7%) with Graves disease. The sensitivity and specificity of micronodulation for autoimmune thyroiditis were 53.9% and 98.3%, respectively.

CONCLUSION

Although the potential for malignant nodules is relatively low in children with diffuse goiter, US can detect focal thyroid disease and characterize the nodules. US thus plays a useful role in excluding autoimmune thyroiditis in this population.

Chronic lymphocytic thyroiditis is associated with invasive characteristics of differentiated thyroid carcinoma in children and adolescents

BACKGROUND

The association between chronic lymphocytic thyroiditis (CLT) and thyroid cancer is an interesting topic. The aim of the present study was to evaluate if demographic and histological characteristics as well as the long-term outcome of thyroid cancer was different in children and adolescents with and without CLT.

METHODS

The medical records of children and adolescents (≤21 years old) were reviewed. The following data were recorded: gender, year and age at diagnosis, family history of thyroid cancer, history of external radiation therapy, histological type (papillary and variants, follicular and variants), tumour size, multifocality, infiltration of thyroid parenchyma or surrounding soft tissues, vascular invasion, presence of lymph node and distant metastases. Information about the presence of TgAb and TPOAb was also collected.

RESULTS

One hundred eight children and adolescents (median age 19.0, interquartile range 4.0 years) were diagnosed with differentiated thyroid carcinoma (DTC); 31 patients (28.7%) presented histological characteristics compatible with CLT. Infiltration of thyroid parenchyma was more frequent in patients with CLT compared to patients without (74.2% vs 48.1% respectively, P=0.024). Familial papillary thyroid carcinoma (PTC) was more frequent in patients with CLT compared to those without CLT (20.7% vs 2.8% respectively, P=0.009). There was no better outcome with respect to the presence of CLT or not.

CONCLUSIONS

Children and adolescents with CLT present more frequently familial PTC as well as thyroid cancer with invasive characteristics.

Predictors of Malignancy in Children with Thyroid Nodules

OBJECTIVE

To evaluate the diagnostic accuracy of clinical, laboratory, and ultrasound (US) imaging characteristics of thyroid nodules in assessing the likelihood of malignancy.

STUDY DESIGN

Data from 184 children and adolescents with thyroid nodules were evaluated and compared with respective cytologic/histologic outcomes. A regression model was designed to assess the predictors associated with malignancy and to calculate ORs.

RESULTS

Twenty-nine malignant neoplasms (25 papillary, 1 medullary, 3 Hurtle-cell carcinomas), 8 follicular adenomas, and 147 goitrous nodules (92 based on cytology, 55 on follow-up) were diagnosed. Fine-needle aspiration biopsy diagnostic accuracy, sensitivity, and specificity were 91%, 100%, and 88%, respectively. Male sex, compression symptoms, palpable lymphopathy, thyroid stimulating hormone concentration, microcalcifications, indistinct margins, hypoechoic US pattern, pathologic lymph node alterations, and increased intranodular vascularization were associated with malignancy. Regular margins, mixed echoic pattern, and peripheral-only vascularization were associated with benignity. During follow-up, nodule growth was associated with malignant disease, especially with levothyroxine therapy. A multivariate analysis confirmed that microcalcifications, hypoechoic pattern, intranodular vascularization, lymph node alterations, and thyroid stimulating hormone concentration were independent predictors of malignant outcome. For each predictor, we provide sensitivity, specificity, and positive/negative predictive values.

CONCLUSIONS

Clinical, laboratory, and US features of nodules can be used as predictors of malignancy in children. Although none has diagnostic accuracy as high as that of fine-needle aspiration biopsy, these predictors should be considered in deciding the diagnostic approach of children with thyroid nodules.

Management Guidelines for Children with Thyroid Nodules and Differentiated Thyroid Cancer

BACKGROUND

Previous guidelines for the management of thyroid nodules and cancers were geared toward adults. Compared with thyroid neoplasms in adults, however, those in the pediatric population exhibit differences in pathophysiology, clinical presentation, and long-term outcomes. Furthermore, therapy that may be recommended for an adult may not be appropriate for a child who is at low risk for death but at higher risk for long-term harm from overly aggressive treatment. For these reasons, unique guidelines for children and adolescents with thyroid tumors are needed.

METHODS

A task force commissioned by the American Thyroid Association (ATA) developed a series of clinically relevant questions pertaining to the management of children with thyroid nodules and differentiated thyroid cancer (DTC). Using an extensive literature search, primarily focused on studies that included subjects ≤18 years of age, the task force identified and reviewed relevant articles through April 2014. Recommendations were made based upon scientific evidence and expert opinion and were graded using a modified schema from the United States Preventive Services Task Force.

RESULTS

These inaugural guidelines provide recommendations for the evaluation and management of thyroid nodules in children and adolescents, including the role and interpretation of ultrasound, fine-needle aspiration cytology, and the management of benign nodules. Recommendations for the evaluation, treatment, and follow-up of children and adolescents with DTC are outlined and include preoperative staging, surgical management, postoperative staging, the role of radioactive iodine therapy, and goals for thyrotropin suppression. Management algorithms are proposed and separate recommendations for papillary and follicular thyroid cancers are provided.

CONCLUSIONS

In response to our charge as an independent task force appointed by the ATA, we developed recommendations based on scientific evidence and expert opinion for the management of thyroid nodules and DTC in children and adolescents. In our opinion, these represent the current optimal care for children and adolescents with these conditions.