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

Children and adolescents with differentiated thyroid cancer from 1998 to 2018: a retrospective analysis

OBJECTIVES

This study aims to investigate the clinical features of differentiated thyroid carcinoma (DTC) in children and adolescents under 18 years and assess the impact of surgery combined with thyroid hormone and radioactive iodine (RAI) on their prognosis.

METHODS

A retrospective observational study was conducted, involving children/adolescents with DTC who underwent surgery at the Head and Neck Department of Tianjin Medical University Cancer Institute and Hospital from January 1998 to December 2018.

RESULTS

Among 198 patients, 130 (65.7 %) were female. According to the American Thyroid Association guidelines, cases were categorized as low (106, 53.5 %), intermediate (54, 27.3 %), and high (38, 19.2 %) risk. The follow-up duration ranged from 3 to 23 years. Local recurrence and distant metastasis were identified in 21 (10.6 %) and 14 (7.1 %) cases, respectively. All patients received levothyroxine, while RAI therapy was administered to intermediate- and high-risk patients. The local recurrence and distant metastasis rates in these two groups were 33.3 and 39.5 %, respectively, with no recurrence or metastasis in the low-risk group. Persistent without structural evidence of disease were 0.9, 3.7, and 26.3 % at end of follow-up for the low-, intermediate-, and high-risk groups, respectively. The overall survival rates for all three groups were 100 %, while disease-free survival rates were 99.1, 63.0, and 34.2 % for the low-, intermediate-, and high-risk groups, respectively.

CONCLUSIONS

Children/adolescents with low-risk DTC exhibited a favorable prognosis even without RAI. However, intermediate- and high-risk DTC patients, despite RAI and levothyroxine treatment, showed elevated rates of persistent disease, local recurrence, and distant metastasis.

Hashimoto's Thyroiditis and Papillary Thyroid Carcinoma: A Follow-Up Study in Patients with Absence of Aggressive Risk Factors at the Surgery of the Primary Tumor

Hashimoto's thyroiditis (HT) is often associated with papillary thyroid carcinoma (PC); it is still a matter of controversy whether the behavior of carcinoma is more aggressive or not. During the follow-up, we retrospectively enrolled 97 patients with PC/HT after thyroidectomy without risk factors at the surgery of the primary tumor, such as multifocality/multicentricity, extrathyroid tumor extension, vascular invasion, neck and distant metastases, and aggressive histological variants. HT diagnosis was confirmed by histology and serum thyroid antibodies. Tumor size was ≤10 mm in 64 cases (microcarcinomas); 206 matched PC patients after thyroidectomy without HT and risk factors were enrolled as controls, totaling 122 microcarcinomas. During follow-up, metastases occurred in 15/97 (15.5%) PC/HT cases, eight microcarcinomas, and in 16/206 (7.8%) without HT, eight microcarcinomas (p = 0.04). Considering both PC/HT and PC patients without HT who developed metastases, univariate analysis showed an increased risk of metastases in patients with HT coexistence, OR: 2.17 (95% CI 1.03-4.60) p = 0.043. Disease-free survival (DFS) was significantly (p = 0.0253) shorter in PC/HT than in the controls. The present study seems to demonstrate that HT is not a cancer protective factor in PC patients given the less favorable outcomes and significantly shorter DFS. HT may also represent an independent recurrence predictor without other risk factors.

Ultrasonographic, clinical, and pathological features of papillary thyroid carcinoma in children and adolescents with or without Hashimoto's thyroiditis

Objective

To compare the ultrasonographic, clinical, and pathological features of children and adolescents with papillary thyroid carcinoma (PTC) with and without Hashimoto's thyroiditis (HT).

Materials and methods

A total of 52 children and adolescent patients surgically diagnosed with PTC between 2017 and 2022 were included; 14 children and adolescent patients with PTC were diagnosed with HT via pathological examination. The preoperative ultrasonographic, postoperative histological, and molecular and clinical characteristics were retrospectively analyzed.

Results

The prevalence rate of PTC in patients with HT was 27%. Papillary thyroid microcarcinomas were found in 11 of 38 patients without HT, but none in patients with HT (p = 0.023). Extrathyroidal extension, capsular invasion, and lymph node metastases were more frequent in patients with PTC and HT than in patients with PTC alone (p < 0.05 for both). The ultrasonographic features of nodule composition, echogenicity, shape, margin, Thyroid Imaging Reporting and Data System categories, and total points were similar. The patterns of echogenic foci were more prominent in the nodules of patients with HT than in those of patients without HT (p = 0.016).

Conclusion

The frequency of papillary thyroid microcarcinomas in patients with PTC and HT was less, whereas that of extrathyroidal extension, capsular invasion, and lymph node metastasis was significantly higher in patients with PTC and HT than in those with PTC alone. The patterns of echogenic foci on ultrasonography may represent a risk for PTC.

Thyroid Nodules in Children and Adolescents: A Single Institution's Experience

OBJECTIVE

The risk of malignancy in pediatric thyroid nodules is higher compared to the risk in adults. Our aim was to investigate the clinical, radiological, and histopathological characteristics of pediatric thyroid nodules.

MATERIALS AND METHODS

The data of 132 children and adolescents who had thyroid nodules were collected retrospectively from medical records.

RESULTS

The mean age of the patients was 12.07 ± 4.08 years and 67% were female. Fine-needle aspiration biopsy was performed in 86 patients (65%) and the results were as follows: benign in 53.4% (n = 46), atypia or follicular lesion of undetermined significance in 3.5% (n = 3), suspicious for follicular neoplasia in 2.3% (n = 2), and malignancy in 32.5% (n = 28). The overall malignancy rate was 22.7% (n = 30). Malignancy was detected after surgery in 2 thyroid nodules belonging to the atypia or follicular lesion of undetermined significance category. Malignancy was detected in 7 patients who had autoimmune thyroiditis and in 1 patient who had congenital dyshormonogenesis. The malignancy rate of the nodules in the patients, who had autoimmune thyroiditis, was found to be 13.4%. Mixed echogenicity, microcalcifications, nodules larger than 10 mm, abnormal lymph nodes, and irregular borders were more common in the malignant group. The nodule size, abnormal lymph nodes, and irregular borders were found to be significant in terms of predicting malignancy.

CONCLUSION

We found malignancy in 22.7% of the thyroid nodules, and the malignancy rate of nodules in the patients, who had autoimmune thyroiditis, was 13.4%. The nodule size, abnormal lymph nodes, and irregular nodule borders emerged as the most significant risk factors for malignancy.

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.

Comparison of Various Ultrasound-Based Malignant Risk Stratification Systems on an Occasion for Assessing Thyroid Nodules in Hashimoto's Thyroiditis

Purpose

To compare the diagnostic performance and unnecessary ultrasound-guided fine-needle aspiration (US-FNA) biopsy rate of the 2015 American Thyroid Association (ATA), 2016 Korean Society of Thyroid Radiology (KSThR), and 2017 American College of Radiology (ACR) guidelines for patients with and without Hashimoto's thyroiditis (HT).

Patients and Methods

This retrospective study included 716 nodules from 696 consecutive patients, which were classified using the categories defined by the three guidelines: ATA, KSThR, and ACR. The malignancy risk in each category was calculated and the diagnostic performance and unnecessary fine-needle aspiration (FNA) rates of the three guidelines were compared.

Results

In total, 426 malignant and 290 benign nodules were identified. Patients with malignant nodules had lower total thyroxine levels and higher thyroid-stimulating hormone, thyroid peroxidase antibody, and thyroglobulin antibody levels than those without malignant nodules (all P<0.01). The margin difference was significant in non-HT patients (P<0.01), but comparable in HT patients (P=0.55). The calculated malignancy risks of high and intermediate suspicion nodules in the ATA and KSThR guidelines and moderately suspicious nodules in the ACR guidelines were significantly lower in non-HT patients compared with HT patients (P<0.05). The ACR guidelines showed the lowest sensitivity, highest specificity, and lowest unnecessary FNA rates in patients with and without HT. Compared to non-HT patients, HT patients had significantly lower unnecessary FNA rates (P<0.01).

Conclusion

HT was associated with a higher malignancy rate of thyroid nodules with intermediate suspicion according to the ATA, KSThR, and ACR guidelines. The three guidelines, especially ACR, were likely to be more effective and could allow a greater reduction in the percentage of benign nodules biopsied in patients with HT.

Characterization of Hashimoto´s thyroiditis in Sudanese children: a cross-sectional study at Gaafar Ibnauf Hospital, Khartoum

Introduction

literature on Hashimoto´s thyroiditis, the common thyroid illness in the young populations, in Sudan and Africa is scarce. We aimed to study its clinical profile and outcome among Sudanese children and adolescents.

Methods

records of 73 patients were reviewed. Data related to demographics, presenting features, family history and coexistence of autoimmune diseases, physical examination findings, and biochemical progression over time were obtained.

Results

patients´ mean age at the diagnosis was 10.6 ± 2.9 years, 80.8% (n = 59) of them were female and 83.6% (n = 61) were residing in iodine-sufficient areas. The commonest presenting features were thyromegaly and fatigability (79.5%, n = 58 and 43.8%, n = 32, respectively) after an illness duration of 0.5-48 months. Autoimmune comorbidities were documented in 8.2% (n = 6) of our series and more than half (53.4%, n = 39) of them were pre-pubertal at the diagnosis. Sixty point three percent (60.3%) (n = 44), 20.5% (n = 15), 13.7% (n = 10) and 5.5% (n = 4) of patients presented with overt hypothyroidism, sub-clinical hypothyroidism, euthyroidism and hyperthyroidism respectively, and there were no significant differences in the clinical profile between them. In patients' continued follow-up, 94.1% (n = 32/34) of those presented with overt hypothyroidism required levothyroxine therapy to maintain euthyroidism for 0.5-13 years, while 85.7% (n = 6/7) of those with euthyroidism remained so for 0.5-6 years. Remission was reported in all hyperthyroid patients and in only 5.9% (n = 2/34) of those with overt hypothyroidism at diagnosis. The majority of our patients with subclinical hypothyroidism were treated with levothyroxine and continued to be euthyroid for 10 months to 13 years.

Conclusion

goiter was the commonest presenting feature of Hashimoto´s thyroiditis. The majority of patients had overt or subclinical hypothyroidism and almost all of them required long-term levothyroxine therapy.

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.

Differences in the management of thyroid nodules in children and adolescents as compared to adults

PURPOSE OF REVIEW

To describe recent advances in the diagnosis and management of thyroid nodules in both children and adults, highlighting differences between the two groups.

RECENT FINDINGS

Thyroid nodules are less common in children than adults but the risk of malignancy is higher. Screening recommendations for patients with certain genetic syndromes or specific risk factors for thyroid nodules and cancer continue to evolve ultrasound is the most appropriate imaging modality for evaluating thyroid nodules in all patients, but radiographic risk stratification systems validated in adults have not been extensively studied in children. Criteria for proceeding to fine needle aspiration (FNA) biopsy differ some between children and adults, with nodule size being less of a consideration in young patients. Molecular testing continues to improve the diagnostic capabilities of FNA for all age groups, but options for pediatric thyroid nodules are currently limited. In children, only oncogene panels are validated and their exact utility, along with miRNA classifiers, is an evolving area of study. For adults, data support selection of a specific molecular test based on ultrasound characteristics and pretest probability of malignancy. Multiple series have shown that fusion mutations are more common in pediatric thyroid nodules, while point mutations are seen more often in adult thyroid nodules. Molecular data help guide management recommendations regarding the need for surgery when FNA is indeterminate, but clinical use is still being refined. Radiofrequency ablation is a nonoperative approach that has gained significant traction for the treatment of symptomatic benign nodules in adults, but data are currently extremely limited in children.

SUMMARY

There are difference in the diagnosis and treatment of thyroid nodules in adults and children, the nuances of which are important for clinical management.

Clinical effect of methimazole combined with selenium in the treatment of toxic diffuse goiter in children

BACKGROUND

The incidence of toxic diffuse goiter (Graves’ disease) is higher in adolescents and preschool-aged children, with an upward trend. The incidence at 6–13 years of age is approximately 11.0%, and the incidences in men and women are 7.8% and 14.3%, respectively.

AIM

To explore the clinical effect of methimazole combined with selenium in the treatment of toxic diffuse goiter (Graves’ disease) in children and its effect on serum anti-thyroglobulin antibody (TRAb) and anti-thyroid peroxidase antibody (TPOAb).

METHODS

A total of 103 children with Graves’ disease treated in our hospital from January 2018 to June 2021 were divided into a traditional group and a combined group (15-20 mg methimazole orally given to children) and a combined group (50 µg selenium added on the basis of traditional treatment) according to different treatment methods to explore the therapeutic effects of the two methods and to observe the changes in thyroid volume and serum TRAb, TPOAb, free thyroxine (FT4) and inflammatory factor levels before and after treatment. The time taken for FT4 to return to normal was compared between the two groups.

RESULTS

Treatment was significantly more effective in the combined group than in the traditional group (P < 0.05). The thyroid volumes of the children in the two groups was measured before and after treatment. Thyroid volume decreased significantly after treatment in both groups, and the thyroid volume was significantly lower in the combined group than in the traditional group (P < 0.05). The serum levels of interleukin-6 (IL-6), IL-8, TRAb, TPOAb and FT4 in the two groups were detected before and after treatment. The levels of IL-6, IL-8, TRAb, TPOAb and FT4 were significantly lower in the combined group than in the traditional group (P < 0.05). Follow-up of the children in the two groups showed that compared with the traditional group, it took less time for children in the combined group to return to the normal level (P < 0.05).

CONCLUSION

Methimazole combined with selenium can effectively treat Graves’ disease in children, reduce the expression of TRAb, TPOAb, FT4 and inflammatory factors, and improve the curative effect. Thus, the combined treatment warrants further clinical research.

Is Hashimoto thyroiditis associated with increasing risk of thyroid malignancies? A systematic review and meta-analysis

Background and purpose

Hashimoto thyroiditis (HT) is the most common inflammatory autoimmune thyroid disease and also the most common cause of hypothyroidism in developed countries. There is evidence of the role of HT in developing thyroid cancers (TCs). This study investigated the association between HT and different types of TCs.

Methods

Results of a comprehensive search in three major databases, as well as hand searching, were screened in title/abstract and full-text stages and the relevant data were extracted from the studies that met the inclusion criteria. Risk of bias (RoB) was assessed using the Joanna Briggs Institute (JBI) critical appraisal tools and the meta-analysis was conducted with Comprehensive Meta-Analysis software.

Results

Out of 4785 records, 50 studies were included in the systematic review, and 27 of them met the criteria for quantitative synthesis. The results indicated a significant role for HT in developing papillary TC (OR: 1.65; 95% CI: 1.04 to 2.61), medullary TC (OR: 2.70; 95% CI: 1.20 to 6.07) and lymphoma (OR:12.92; 95% CI: 2.15 to 77.63); but not anaplastic TC (OR: 1.92; 95% CI: 0.29 to 1.90) and follicular TC (OR: 0.73; 95% CI: 0.41 to 1.27). Also, this study found a significant association between HT and thyroid malignancies (OR: 1.36; 95% CI: 1.05 to 1.77).

Conclusion

Although we found a significant association between HT and some types of TCs, High RoB studies, high level of heterogeneity, and the limited number of well-designed prospective studies, suggested the need for more studies to reach more reliable evidence.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13044-021-00117-x.

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.

Clinical, biochemical, and radiological follow-up results of children and adolescents with Hashimoto's thyroiditis: a single-center experience

OBJECTIVES

Hashimoto's thyroiditis (HT) is the most common cause of goiter and acquired hypothyroidism in children and adolescents, especially in areas without endemic iodine deficiency. We aimed to evaluate the follow-up results of children and adolescents diagnosed with HT, including clinical, biochemical, and radiological findings and treatment approaches.

METHODS

HT patients, who were diagnosed between 2012 and 2018 years in a single-center, were assessed retrospectively.

RESULTS

Two hundred and twenty-four cases were included in the study, 75.9% of whom were girls (female/male ratio: 3.1) and 66.5% were pubertal. The median age of the cases at first admission was 12.5 (9.2-15) years. The median follow-up period of 196 patients, who continued their follow-up regularly, was 2.1 (0.7-4.8) years. When autoantibody levels were analyzed according to gender, mean anti-Tg levels were higher in girls (p=0.028), whereas anti-TPO levels were similar (p=0.372). A nodule was detected in the ultrasonographic follow-up of 29 (13%) patients. Papillary thyroid carcinoma was observed in 10.3% (n=3) of those with nodules. When the last ultrasonography findings of 188 patients with available radiological follow-up data were compared with their initial evaluation, the rate of heterogeneous parenchymal echogenicity increased significantly (p=0.008). The need for l-thyroxine dosage augmented over time.

CONCLUSIONS

Although HT is more common in adolescent girls, it can be encountered in both genders and at all ages in childhood. The incidence of malignancy was not higher in patients with nodules associated with HT than the reported incidences of malignancy in nodules not associated with HT.

Management of Differentiated Thyroid Carcinoma in Pediatric Patients

Differentiated thyroid carcinomas are rare in young children but represent almost 10% of all malignancies diagnosed in older adolescents. Differentiated thyroid carcinoma in children is more likely to demonstrate nodal involvement and is associated with higher recurrence rates than seen in adults. Decisions regarding extent of surgical resection are based on clinical and radiologic features, cytology, and risk assessment. Total thyroidectomy and compartment-based resection of involved lymph node basins form the cornerstone of treatment. The use of molecular genetics to inform treatment strategies and the use of targeted therapies to unresectable progressive disease is evolving.

Predictive Values of Inflammation-Related Markers and Thyroid Function in Pediatric Thyroid Cancer Patients

Few researchers have studied the diagnostic value of inflammation-related hematological indexes of pediatric thyroid carcinoma exclusively. Whether thyroid-stimulating hormone (TSH) is an independent risk factor for pediatric thyroid cancer is still controversial. To assess the correlativity and predictive values of inflammation-related markers and thyroid function in pediatric thyroid cancer patients, we collected a total of 270 children with thyroid nodules for two consecutive years. Clinical data including age, gender, thyroid function, inflammation indexes, and clinical pathologic finding were collected and analyzed. The above-mentioned data were compared between the benign group and the malignant group, followed by the subgroups comparison. Binary logistic regression analysis was used to evaluate the correlation of markers and the pathological features of thyroid nodules. The neutrophil-to-lymphocyte ratio (NLR) showed a significant difference between thyroid cancer and thyroid nodules, while TSH did not. NLR > 1.49529 was the prognostic indicator of pediatric thyroid cancer. The logistic regression model further revealed that NLR > 1.49529 was an independent risk factor for thyroid cancer in pediatric patients. Furthermore, TSH was not correlated with the tumor characteristics in the thyroid cancer group. In conclusion, the findings in this study showed that NLR could be a predictor of thyroid cancer in pediatric patients and refuted the present view that TSH is a risk factor in pediatric thyroid cancer.

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.