Surgical management of follicular thyroid carcinoma in children and adolescents: A study of 30 cases

Clinicopathological Findings of 220 Pediatric, Adolescent, and Young Adult Patients with Thyroid Cancer in Fukushima Medical University Hospital

Background: Thyroid ultrasound examinations (TUEs), conducted as part of the Fukushima Health Management Survey (FHMS), were initiated to monitor the health status of residents after the Fukushima Daiichi Nuclear Power Plant accident owing to concerns regarding the increased incidence of thyroid cancer among children, as observed after the Chernobyl Nuclear Power Plant accident. This study reported the clinicopathological characteristics of patients with thyroid cancer diagnosed through the FHMS and treated at the Fukushima Medical University Hospital. Methods: Data regarding the clinicopathological characteristics of patients with thyroid cancer were collected and evaluated in this descriptive study. Results: Among the 263 patients diagnosed with thyroid cancer as of September 2021, 220 patients with cytologically diagnosed thyroid cancer were treated as referrals from the FHMS. The median (interquartile range) age at the time of diagnosis was 18.6 (16.2-20.3) years. The median maximum tumor diameter was 13.0 (10.4-18.0) mm. To reduce surgical invasiveness, 199 patients (90.1%) underwent unilateral lobectomy. Pathological findings were suggestive of papillary thyroid carcinomas (PTC) in 216 (98.2%) patients; among them, 205 patients had PTC of the classical type. In addition, 216 (98.2%) patients had stage I disease. Cancer cell extension in the sternothyroid muscle or perithyroidal soft tissues and microscopic lymphovascular invasion were observed in 112 (50.9%) and 123 (55.9%) patients, respectively. No differences were observed between the two age groups (<18.6 years and ≥18.6 years) in terms of the clinical or pathological characteristics of thyroid cancer: risk classification (p = 0.69) and American Thyroid Association pediatric risk level (p = 0.24). Compared with those from previous reports, few surgical complications were observed. Conclusions: Patients with thyroid cancer diagnosed with TUEs underwent safe and minimally invasive operations, and careful postoperative follow-up was provided. The pathological findings of the detected thyroid cancers indicated that the majority were classical papillary carcinomas, and approximately half of the patients had extrathyroidal or lymphovascular invasion. No differences were observed between the two age groups in terms of the clinical or pathological characteristics of thyroid cancer.

Risk factors for death of follicular thyroid carcinoma: a systematic review and meta-analysis

BACKGROUND

There are conflicting reports on the factors that increase the likelihood of patients dying from follicular thyroid carcinoma (FTC). Therefore, it is critical to identify risk factors of patients with FTC. This study aimed to identify the factors that increase the risk of death of patients with FTC and help clinicians make better treatment and follow-up decisions.

METHODS

A systematic literature review was conducted in PubMed and Web of Science databases for relevant studies published before January 31, 2023. Their reference lists were also analyzed. Two reviewers extracted data and evaluated the quality of eligible studies independently. Studies on patients who had open thyroidectomy procedures with or without neck dissection were included in this review. The RevMan 5.3 software was used to analyze the data.

RESULTS

This meta-analysis included thirteen studies with a total of 2075 patients. The following variables were associated with an increased risk of death in FTC patients: age > 45 years, male, tumor diameter > 4 cm, multifocality, extrathyroidal extension (ETE), widely invasive (WI), cervical lymph node metastasis (CLNM), distant metastases (DM) and non-radical resection tumor. Lobectomy and no radioactive iodine (RAI) treatment was not associated with the death of FTC patients.

CONCLUSION

Clinicians should pay closer attention to the following significant risk factors associated with the death of FTC patients: age (> 45), male, multifocality, tumor diameter > 4 cm, ETE, WI, non-radical resection tumor, CLNM, and DM. Individualized initial treatment and close follow-up are needed FTC patients who have these risk factors.

Multi-Omics and Management of Follicular Carcinoma of the Thyroid

Follicular thyroid carcinoma (FTC) is the second most common cancer of the thyroid gland, accounting for up to 20% of all primary malignant tumors in iodine-replete areas. The diagnostic work-up, staging, risk stratification, management, and follow-up strategies in patients who have FTC are modeled after those of papillary thyroid carcinoma (PTC), even though FTC is more aggressive. FTC has a greater propensity for haematogenous metastasis than PTC. Furthermore, FTC is a phenotypically and genotypically heterogeneous disease. The diagnosis and identification of markers of an aggressive FTC depend on the expertise and thoroughness of pathologists during histopathological analysis. An untreated or metastatic FTC is likely to de-differentiate and become poorly differentiated or undifferentiated and resistant to standard treatment. While thyroid lobectomy is adequate for the treatment of selected patients who have low-risk FTC, it is not advisable for patients whose tumor is larger than 4 cm in diameter or has extensive extra-thyroidal extension. Lobectomy is also not adequate for tumors that have aggressive mutations. Although the prognosis for over 80% of PTC and FTC is good, nearly 20% of the tumors behave aggressively. The introduction of radiomics, pathomics, genomics, transcriptomics, metabolomics, and liquid biopsy have led to improvements in the understanding of tumorigenesis, progression, treatment response, and prognostication of thyroid cancer. The article reviews the challenges that are encountered during the diagnostic work-up, staging, risk stratification, management, and follow-up of patients who have FTC. How the application of multi-omics can strengthen decision-making during the management of follicular carcinoma is also discussed.

Thyroid nodules in children and adolescents: Investigation and management

Clinically detectable thyroid nodules are less common in children than adults. However, they are associated with an increased risk of malignancy. Therefore, thorough evaluation of paediatric thyroid nodules is necessary, and an understanding of the features associated with a higher risk of malignancy is important to guide management and referral. Thyroid cancer in children differs significantly from that seen in adults in terms of genetics, presentation, response to treatment and prognosis. Children often present with more advanced disease, but the vast majority have excellent long-term prognosis. Evaluation and management of thyroid nodules and thyroid cancer require a multidisciplinary team approach and involvement of specialists with experience in this field. This review summarises investigative pathways for thyroid nodules in children and outlines current management strategies for paediatric thyroid nodules and cancer.

Thyroid Surgery in Children: A 5-Year Retrospective Study at a Single Paediatric Surgical Center and Systematic Review

The aim of this study was to analyse and evaluate our 5-year experience in paediatric thyroid surgery, as well as the specificities of this kind of surgery in the literature. This retrospective study was based on 19 operations in 17 patients aged from 5 to 17 years who were operated on due to thyroid pathology from 2017 until 2022. We presented data on surgical procedures and complications following surgery. Most of the patients were adolescent girls. The most common clinical presentations included enlarged thyroid gland, followed by thyroid nodules and hyperthyroidism. Eight total thyroidectomies, five left lobectomies, five right lobectomies, and three central neck dissections were performed. The most common histopathological diagnosis was hyperplastic diffuse colloid goitre, followed by papillary carcinoma, cystic nodule, follicular adenoma, Hashimoto thyroiditis and toxic adenoma. Postoperative course was uneventful, with four mild complications (one wound infection, one manifest hypocalcaemia, and two transitory recurrent laryngeal nerve paralysis). In our literature review, eighteen full-text articles were included and analysed. This study demonstrated that thyroid surgery in paediatric population is a safe and efficient procedure. Thyroid pathology in children significantly differs from that in the adults, and paediatric surgeons should be included into the team managing such cases.

Paediatric differentiated thyroid carcinoma: a UK National Clinical Practice Consensus Guideline

This guideline is written as a reference document for clinicians presented with the challenge of managing paediatric patients with differentiated thyroid carcinoma up to the age of 19 years. Care of paediatric patients with differentiated thyroid carcinoma differs in key aspects from that of adults, and there have been several recent developments in the care pathways for this condition; this guideline has sought to identify and attend to these areas. It addresses the presentation, clinical assessment, diagnosis, management (both surgical and medical), genetic counselling, follow-up and prognosis of affected patients. The guideline development group formed of a multi-disciplinary panel of sub-speciality experts carried out a systematic primary literature review and Delphi Consensus exercise. The guideline was developed in accordance with The Appraisal of Guidelines Research and Evaluation Instrument II criteria, with input from stakeholders including charities and patient groups. Based on scientific evidence and expert opinion, 58 recommendations have been collected to produce a clear, pragmatic set of management guidelines. It is intended as an evidence base for future optimal management and to improve the quality of clinical care of paediatric patients with differentiated thyroid carcinoma.

Outcome and complications after surgery for thyroid carcinoma in pediatric age—an evaluation of practice

Objectives

To discuss management protocol, surgical complications, and outcomes of thyroid carcinoma in children.

Methods

We performed a retrospective analysis including all pediatric patients with thyroid carcinoma who were managed at our institution between January 2011 and January 2021. Data were analyzed regarding demographics, clinical features, operative details, postoperative complications, and survival data.

Results

Thirty-two patients were identified; 26 females (81.25%) and 6 males (18.75%). The median age at operation was 14 years (range: 5–18). Twenty-six (81.25%) patients presented with palpable thyroid swelling. Median tumor size was 3 cm (range: 1–7). Metastatic workup did not detect any pulmonary metastases. Total thyroidectomy was performed in 25 patients (78%), and 16 of them underwent additional bilateral neck dissection (16 had central nodal dissection, and 7 had both central and lateral nodal dissection). Seven patients (22%) underwent hemithyroidectomy, and only one of them had a completion thyroidectomy after 2 weeks. Conservative resection was adopted in six children with similar criteria (tumor size < 1.5 cm in one lobe, no extrathyroid extension, differentiated thyroid carcinoma, no detected lymph nodes). Postoperative complications occurred in eight patients (all had total thyroidectomy) with an overall incidence of 25%. Seven patients had transient morbidities that were managed conservatively (chylous leak n = 1, hypoparathyroidism n = 3, and nerve palsy n = 3). At a median follow-up time of 54 months, four patients had relapsed (all underwent total thyroidectomy). The 5-year OS and EFS were 100% and 87.5%, respectively.

Conclusion

Operative resection for pediatric thyroid carcinoma can be performed with average short-term complications and achieving excellent outcomes. Total thyroidectomy remains the standard procedure of choice in the majority of those patients. However, conservative surgery can be successfully adopted in a well-selected group of children with favorable long-term results as per our findings.

Factors associated with postoperative hypocalcemia following thyroidectomy in childhood

BACKGROUND

Postoperative hypocalcemia is a frequent complication after thyroidectomy. Hypoparathyroidism may develop as transient (TtHP), with normalization within six months from surgery, or permanent (PtHP) if the patient requires replacement therapy. We analyzed factors associated with the development of postoperative hypoparathyroidism and in detail PtHP following thyroid surgery in a pediatric population.

PROCEDURE

A retrospective multicenter study analyzing 326 patients was carried out. We recorded gender, age, tumor size, thyroiditis, extrathyroidal extension, lymph node dissection (central/lateral compartment, unilateral/bilateral), parathyroid autotransplantation, and histology. Additionally, calcium levels were acquired postoperatively.

RESULTS

We analyzed pediatric patients ≤18 years who underwent thyroidectomy clustered into age groups (≤15 or > 15). Patients' mean follow-up was 5.8 years (1-11 years). Postoperative hypoparathyroidism occurred in 36 (11.0%): 20 cases (6.13%) developed PtHP. Postoperative hypoparathyroidism was more frequent in younger patients (P = 0.014), in larger tumors (P < 0.001), in case of extrathyroidal extension (P = 0.037), and in central compartment (P = 0.020) and bilateral lymph node dissection (P = 0.030). PtHP was more frequent in older patients (P = 0.014), in case of thyroiditis (P < 0.001), and extrathyroidal extension (P < 0.001). Concerning the first postoperative calcium level measurement, in the postoperative hypoparathyroidism group, we registered a 8.17 mg/dL value with 14% pre/postoperative decrease (Δ_Ca ), whereas in PtHP patient group calcium level was 7.91 mg/dL with 16.7% Δ_Ca .

CONCLUSIONS

The risk of postoperative hypoparathyroidism is related to younger age, tumor size, central compartment and bilateral lymph node dissection, extrathyroidal extension, and decrease in postoperative calcium levels. The risk of PtHP is related to older age, thyroiditis, extrathyroidal extension, and decrease in postoperative calcium levels.

Therapeutic challenges in metastatic follicular thyroid cancer occurring in pregnancy: A case report

BACKGROUND

Hormones could play a role in the evolution of follicular thyroid cancer (FTC) for which we discuss an unusual presentation of FTC occurring during pregnancy.

CASE SUMMARY

A pregnant woman was admitted with FTC metastasis resulting in a gluteal mass. Preoperative abdominal computed tomography revealed liver metastasis for which the patient underwent total thyroidectomy and liver resection, oral radioiodine therapy and radiotherapy, followed by embolization of the pelvic mass. The patient died of cerebral hemorrhage 16 mo after the initial diagnosis.

CONCLUSION

Human chorionic gonadotropin and estrogen stimulation might have a role in cancer growth, especially during pregnancy. FTC management aims to stop disease progression and overcome hormonal imbalances after thyroidectomy thus reducing fetal complications. It is still under debate whether it is possible to combine optimal timing for treatment to ensure the best possible outcome with reduction of fetal complications and risk of cancer growth.

Increased trend of thyroid cancer in childhood over the last 30 years in EU countries: a call for the pediatric surgeon

Given the increasing incidence of thyroid cancer cases affecting the pediatric population in Europe, an epidemiological analysis of the available data is essential in order to update standards of care and recommend diagnostic and therapeutic strategies coherent to the new epidemiological trend. An observational study was conducted, considering the time interval 1991-2012, acquiring data collected by the International Agency for Research on Cancer (IARC) through the "Cancer Incidence in 5 continents plus" (CI5 plus) project and dividing patients into four groups of age (0-4, 5-9, 10-14, 15-19 years old). Data retrieved were compared to the latest report from Global Cancer Observatory, collected through the GLOBOCAN 2020 project, dividing patients in two groups: age 10-14, 15-19. Our findings highlighted an increasing prevalence of thyroid cancer rates in patients aged from 10 to 15 years old and from 15 to 19 years old, mainly in the female population, in Belarus (from 1991 to 2007), Cyprus, and Italy (from 2008 to 2012). Moreover, a further increase in incidence was highlighted in Italy according to data from GLOBOCAN 2020, with respect to other European countries.

CONCLUSION

An increasing prevalence of thyroid cancer is seen in age groups 10-19. Further research is required to understand the underlying cause and concomitantly identify the most proper screening and diagnostic techniques of thyroid nodules. Indeed, this is crucial to reach optimal surgical standards and better prognosis, possibly with more conservative approaches and maybe less postoperative complications.

WHAT IS KNOWN

• Thyroid cancer is the 4th most common malignancy in children.

WHAT IS NEW

• In the last decades, an increasing pattern has been recorded. • In the US, it has outlined breast cancers as the most common cancer in females.

Retrospective analysis of clinical characteristics and risk factors of differentiated thyroid cancer in children

BACKGROUND

The incidence rate of children with thyroid cancer has an increasing trend. This study aimed to investigate the clinical characteristics and therapeutic approaches of differentiated thyroid cancer (DTC) in Chinese children.

MATERIALS AND METHODS

From January 1998 to March 2022, 52 cases undergoing surgical resection in Xinhua Hospital affiliated to Shanghai Jiao Tong University were divided by age (≤ 7 years old: n = 14 and 8-13 years old, n = 38). Treatment methods and clinical features were analyzed to evaluate prognostic factors for oncological outcomes.

RESULTS

Among the 52 cases, the proportion of local invasion in the pre-school group was found to be higher than that in the school-age group (p = 0.01). T stage was significantly different between the two groups (p ≤ 0.05); the proportion of T_1-2 was higher in the school-age group (32 cases, 84.2%), while the proportion of T₄ was higher in the pre-school group (6 cases, 42.8%) relatively. The postoperative complication rate was dramatically higher in pre-school children (p ≤ 0.05). Additionally, the total thyroidectomy rate in the non-recurrent group was slightly higher than that in the recurrent group (p ≤ 0.05). Over half of the recurrent cases had low T stage and low ATA (American Thyroid Association) risk levels at initial diagnosis (78.3 and 51.4%).

CONCLUSION

The local invasion, tumor stage, and recurrent laryngeal nerve (RLN) injury rates of the pre-school group were higher than that of the school-age group, where young age served as a potential hazard in DTC children. Hence, surgeons should emphasize high-risk features and optimize individualized surgical procedures for DTC children.

Long-Term Oncological Outcomes of Papillary Thyroid Cancer and Follicular Thyroid Cancer in Children: A Nationwide Population-Based Study

INTRODUCTION

Pediatric thyroid carcinoma is a rare malignancy and data on long-term oncological outcomes are sparse. The aim of this study was to describe the long-term oncological outcomes of pediatric papillary thyroid carcinoma (PTC) and follicular thyroid carcinoma (FTC) in a national cohort, and to identify risk factors for recurrence.

METHODS

We conducted a nationwide, retrospective cohort study, in which we combined two national databases. Patients aged <18 years, diagnosed with PTC or FTC in the Netherlands between 2000 and 2016, were included. pT-stage, pN-stage, multifocality and angioinvasion were included in a Cox-regression analysis for the identification of risk factors for recurrence.

RESULTS

133 patients were included: 110 with PTC and 23 with FTC. Patients with PTC most often presented with pT2 tumors (24%) and pN1b (45%). During a median follow-up of 11.3 years, 21 patients with PTC developed a recurrence (19%). Nineteen recurrences were regional (91%) and 2 were pulmonary (9%). No risk factors for recurrence could be determined. One patient who developed pulmonary recurrence died two years later. Cause of death was not captured. Patients with FTC most often presented with pT2 tumors (57%). One patient presented with pN1b (4%). In 70%, no lymph nodes were collected. None of the patients with FTC developed a recurrence or died.

CONCLUSION

Pediatric PTC and FTC are two distinct diseases. Recurrence in pediatric PTC is common, but in FTC it is not. Survival for both pediatric PTC and FTC is very good.

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

Background

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

Methods

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

Results

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

Conclusions

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

Predominant DICER1 Pathogenic Variants in Pediatric Follicular Thyroid Carcinomas

Background: Pediatric thyroid cancer has characteristics that are distinct from adulthood thyroid cancer. Due to its very low prevalence, little is known about the genetic characteristics of pediatric follicular thyroid cancer (FTC). Methods: We investigated genetic alterations in tumor tissues from 15 patients aged <20 years (median: 14.3 years; range: 2.4 - 19.0 years) using multifaceted approaches. Whole-exome sequencing, targeted next-generation sequencing using a cancer gene panel, and Sanger sequencing of the major exons of the H/K/N-RAS and DICER1 genes and the promoter region of the TERT gene were performed. Normal tissues or blood of patients with DICER1- or PTEN-positive tumors was also evaluated to determine whether the variant is germ line. Results: The median tumor size was 3.1 cm (range: 0.6 - 6.4 cm). Four patients exhibited angioinvasion and one extensive capsular invasion; none showed evidence of disease over a median of 8.1 years. Eight patients (53.3%) had DICER1 variants, including four with DICER1 syndrome (three patients were <10 years of age). One patient had a germ line PTEN frameshift variant with the diagnosis of PTEN hamartoma tumor syndrome. One patient had a PAX8/PPARγ rearrangement, and two patients had no genetic driver alteration other than multiple loss of heterozygosity with or without copy number alterations in their tumors. No RAS or TERT variants were found. Nodular hyperplasia and follicular adenoma (FA) coexisted in DICER1 variant-positive FTCs more frequently than variant-negative FTCs (p = 0.026). All DICER1 variant-positive FTCs had a somatic missense variant at metal binding sites (six at codon p.E1813 and two at codon p.D1709) within the RNase IIIb domain; seven had other missense, nonsense, or frameshift variants in the DICER1 gene. Six coexisting FAs of two patients with DICER1 syndrome (three of each) had additional somatic variants at metal binding sites within the RNase IIIb domain (codon p.E1705, p.D1709, p.D1810, or p.E1813), different from each other and from the indexed FTC tumor. Conclusions: Pediatric FTCs have distinct genomic alterations and pathogenesis compared with adults, particularly those characterized by DICER1 variants. The DICER1 variant should be considered in pediatric FTCs, especially in cases <10 years of age. In all DICER1 variant-positive FTCs and FAs, recurrent hotspot variants were found at metal binding sites within the RNase IIIb domain, suggesting they impact tumorigenesis.

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.