Differentiated thyroid cancer in children and adolescents: clinical outcome and mortality after long-term follow-up

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.

Differentiated Thyroid Cancer in Children and Adolescents: Long Term Outcome and Risk Factors for Persistent Disease

Simple Summary

Despite their excellent prognosis, pediatric differentiated thyroid cancers (P-DTC) often undergo aggressive treatment due to the advanced disease presentation. Reliable risk stratification tools to guide management are needed; unfortunately, the current American Thyroid Association (ATA) classification for P-DTC lacks an unequivocal definition of the three risk categories. In line with previous work, our data confirm a favorable long-term outcome in P-DTC including cases with distant metastases. We propose a modified ATA pediatric risk stratification using a cut-off of five lymph nodes as proposed by the 2015 ATA guidelines for adult DTC. The modified pediatric ATA risk class independently predicted short- and long-term outcome. The utility of applying dynamic risk classification was also confirmed as P-DTC with an excellent response seldom experiences relapse.

Abstract

Background: Pediatric differentiated thyroid cancer (P-DTC) frequently presents with advanced disease. The study aim was to evaluate the outcome of P-DTC and a modified 2015 American Thyroid Association risk classification (ATA-R). Methods: A retrospective study of consecutive P-DTC patients was performed. The ATA-R for P-DTC was used with a cut-off of ≤ 5 N1a for low-risk. The outcome could be excellent response (ER) (thyroglobulin < 1 ng/mL and no evidence of disease (EoD) at imaging), biochemical incomplete response (BIR) (thyroglobulin ≥ 1 ng/mL and no EoD at imaging) or structural incomplete response (SIR) (EoD at imaging). Results: We studied 260 P-DTC (70% females; median age at diagnosis 14 years; 93% total thyroidectomy and 82% lymph node dissection). The ATA-R was low in 30% cases, intermediate in 15% and high in 55%, including 31.5% with distant metastases. Radioiodine treatment was administered in 218 (83.8%), and further radioiodine and surgery was performed in 113 (52%) and 76 (29%) patients, respectively. After a median follow-up of 8.2 years, the outcome was ER in 193 (74.3%), BIR in 17 (6.5%) and SIR in 50 (19.2%). Independent predictors of SIR or BIR at first and last visits were ATA-R intermediate or high. Conclusion: P-DTC has an excellent prognosis. Modified ATA-R is a useful prognostic tool in P-DTC to guide management.

Distant Metastases From Childhood Differentiated Thyroid Carcinoma: Clinical Course and Mutational Landscape

CONTEXT

Distant metastases (DM) from childhood differentiated thyroid carcinoma (DTC) are uncommon and published studies are limited.

OBJECTIVE

This work aimed to describe the outcomes of patients with DM from childhood DTC and to evaluate the molecular landscape of these tumors.

METHODS

A retrospective study was conducted at a tertiary cancer center including patients with pediatric DTC (diagnosed at age ≤ 18 years from 1946 to 2019) and DM.

RESULTS

We identified 148 patients; 144 (97%) had papillary thyroid carcinoma (PTC) and 104 (70%) were female. Median age at DTC diagnosis was 13.4 years (interquartile range [IQR], 9.9-15.9 years). Evaluable individuals received a median of 2 (IQR, 1-3) radioactive iodine (RAI) treatments at a median cumulative administered activity of 238.0 mCi (IQR, 147.5-351.0 mCi). The oncogenic driver was determined in 64 of 69 PTC samples: RET fusion (38/64; 59%), NTRK1/3 fusions (18/64; 28%), and the BRAF V600E mutation (8/64; 13%). At last evaluation, 93% had persistent disease. The median overall and disease-specific survival after DTC diagnosis were 50.7 and 52.8 years, respectively. Eight (5%) PTC patients died of disease after a median of 30.7 years (IQR, 20.6-37.6 years).

CONCLUSION

Childhood DTC with DM persists in most patients despite multiple courses of RAI, but disease-specific death is uncommon, typically occurring decades after diagnosis. Fusion genes are highly prevalent in PTC, and all identified molecular alterations have appropriate targeted therapies. Future studies should focus on expanding genotype-phenotype correlations, determining how to integrate molecularly targeted therapy into treatment paradigms, and relying less on repeated courses of RAI to achieve cure in patients with DM from childhood DTC.

[Differentiated thyroid cancer in children and adolescents: about 22 cases]

L’obectif était de mettre en relief les particularités du cancer de la thyroïde chez l’enfant et l’adolescent, et d’évaluer nos résultats par rapport à la littérature internationale a travers une série de cas la plus représentatif au Maroc: 22 cas. C'est une étude rétrospective descriptive des patients atteints de cancer différencié de la thyroïde, hospitalisés au service d’ORL et de Chirurgie Cervico-faciale de L’hopital 20 Août de Casablanca-Maroc, sur la période qui s’étend de Janvier 1995 à Mars 2015. Nous avons recueilli les données relatives à 22 cas, qui répondaient à nos critères d’inclusion. L’âge moyen de nos patients était de 14 ans, avec une sex-ratio 3,4, la plupart de nos patients ont consulté pour un nodule thyroïdien, associé dans 22,7% des cas à une adénopathie cervicale, et dans 9,1% à des signes de compression. L’ensemble des patients ont bénéficié d’une thyroïdectomie totale, suivie d’un curage ganglionnaire dans 31,82%. Le diagnostic de cancer thyroïdien a reposé sur l’examen anatomopathologique de la pièce opératoire, qui a objectivé un carcinome papillaire dans 95,4% des cas, et un carcinome vésiculaire dans 4,5%. Le traitement par l’iode radioactif 131 a été réalisé dans 100% des cas. Par la suite tous nos patients ont été mis sous hormonothérapie thyroïdienne. Une surveillance étroite et régulière a permis de détecter des métastases ganglionnaires chez 3 patients, et les métastases à distance chez 4 patients. Le cancer différencié de la thyroïde de l’enfant et l’adolescent est une entité rare mais agressive, son traitement se base sur la chirurgie, associée à l’irathérapie donnant un pronostic excellent.

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.

Predictive factors for recurrence of differentiated thyroid cancer in patients under 21 years of age and a meta-analysis of the current literature

The influence of predictors for recurrence in relation to recurrence-free survival was analyzed retrospectively in differentiated thyroid cancer (DTC) patients under 21 years of age who underwent primary surgical treatment and who had a pathological diagnosis of DTC between 1983 and 2012 at Fudan University Cancer Hospital. Recurrences were retrospectively analyzed using a Cox regression model for the hazard ratio (HR) according to the clinicopathological features. A meta-analysis was performed with respect to the potential predictors for recurrence from current related studies. In the present study, there were 146 young patients aged from 7 to 20 years, with a female/male ratio of 2.65/1. Female gender was the only factor significantly associated with recurrence according to univariate (HR = 2.812, P = 0.037) and multivariate (HR = 4.107, P = 0.024) Cox regression analyses. Meta-analyses revealed that multifocality (HR = 1.91, P < 0.05) and presentation at diagnosis (HR = 1.39, P < 0.05) were highly associated with recurrence in young DTC patients. However, female gender and other factors, such as age (≤10 vs. 11-20 years), PTC (PTC vs. FTC), extrathyroidal extension, lymph node metastasis, total thyroidectomy (total vs. less than total), radioiodine therapy, and radiation history, were not associated with recurrence in young DTC patients. In conclusion, multifocality and presentation at diagnosis are strong predictive factors of recurrence in relation to recurrence-free survival. We recommend studies with larger sample sizes and longer follow-up to verify the influence of predictors for disease recurrence in young patients.

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.

Pediatric patients with multifocal papillary thyroid cancer have higher recurrence rates than adult patients: a retrospective analysis of a large pediatric thyroid cancer cohort over 33 years

CONTEXT

Large-sample studies with long-term follow-up data are limited for pediatric patients with thyroid cancer.

OBJECTIVE

Secular changes in clinicopathological characteristics and outcomes in pediatric patients with thyroid cancer were investigated and compared with those of adults.

DESIGN AND PATIENTS

A retrospective review of 150 pediatric patients with thyroid cancer managed between 1980 and 2013 was conducted. The long-term outcomes of 124 patients followed up for 12 months or longer were evaluated. Predictors of recurrence-free survival (RFS) in pediatric patients with papillary thyroid cancer (ped-PTC group) were compared with those of 3071 adult patients.

RESULTS

The proportion of small tumors (<1 cm) increased from 9.0% before 2010 to 36.8% after 2010 (P < .001); however, neither pathological presentations such as multifocality, extrathyroidal extension (ETE), lymph node (LN) metastasis, or lung metastasis nor the RFS rate changed over time. The 5- and 10-year recurrence rates were 14.5% and 34.4% in pediatric patients, respectively. In respective analyses of the ped-PTC group and patients of all ages with papillary thyroid cancer (all ages group), the rates of ETE, LN metastasis, and lung metastasis were higher with younger age (all P for trend <.05). RFS was lower in the pediatric than the adult patients aged 20-54 years (P < .005) and was comparable with that of older patients (≥ 55 y). Only tumor multifocality and size predicted recurrence in the ped-PTC group (P < .05), whereas LN metastasis and ETE also predicted recurrence in the all-ages group (P < .01). Among patients in the all-ages group with multifocal tumors, pediatric patients had the lowest RFS (P < .05).

CONCLUSIONS

The pathological characteristics and recurrence rates of pediatric thyroid cancer have not changed over 33 years. Although younger patients present with more advanced disease, multifocality rather than age at diagnosis predicted recurrence. Recurrence was higher in pediatric than adult patients with multifocal papillary thyroid cancer.

Increase in the incidence of differentiated thyroid carcinoma in children, adolescents, and young adults: a population-based study

OBJECTIVE

To investigate trends in incidence of differentiated thyroid carcinomas among children and adolescents and young adults.

STUDY DESIGN

In this ecological time-trends study, we selected cases of differentiated thyroid carcinomas (1984-2010) in patients <30 years from Surveillance, Epidemiology, and End Results 9 cancer registries by using International Classification of Diseases for Oncology, 3rd edition, codes for papillary and follicular cancers. Patients with multiple other primary diseases before differentiated thyroid carcinomas were excluded. SEER*Stat software, version 8.0.4 (National Cancer Institute, Bethesda, Maryland) was used to calculate age-standardized rates (estimated per 1,000,000/persons) and annual percentage changes (APCs) were calculated by the Joinpoint model (Joinpoint software, version 4.0.4; National Cancer Institute).

RESULTS

Rates ranged from 2.77 (1990) to 9.63 (2009) and from 18.35 (1987) to 50.99 (2009), for male and female subjects, respectively. A significant increasing trend in incidence was observed for both male (APC 3.44; 95% CI 2.60-4.28) and female (APC 3.81; 95% CI 3.38-4.24) patients. When a stratified analysis on the basis of tumor size was performed, significant increasing trends were noted for the following categories: <0.5 cm (females: APC 5.09, 95% CI 3.54-6.65), 0.5-0.9 cm (females: APC 8.45, 95% CI 7.09-9.82), 1.0-1.9 cm (males: APC 5.09, 95% CI 3.20-7.01; females: APC 3.42, 95% CI 2.78-4.07), and ≥2 cm (males: APC 2.62, 95% CI 1.64-3.60; females: APC 2.96, 95% CI 2.34-3.59).

CONCLUSIONS

Incidence rates for differentiated thyroid carcinomas are increasing among children and adolescents and young adults in the US. The increasing trends for larger tumors rules out diagnostic scrutiny as the only explanation for the observed results. Environmental, dietary, and genetic influences should be investigated.

Surgical management of well-differentiated thyroid carcinoma in children and adolescents: 33 years of experience of a single institution in Serbia

Well-differentiated thyroid carcinoma in children and adolescents is rare but demonstrates aggressive behavior. Gross lymph node metastases and distant metastases are common upon first clinical presentation. During a 33-year period (1981-2014) at the Institute of Oncology and Radiology of Serbia, 62 children and adolescents underwent surgery due to well-differentiated thyroid carcinoma. Mean age was 16.7 (range 7-21) years. At the time of diagnosis 6% of patients had lung metastases. Total thyroidectomy or completion thyroidectomy was performed for all patients followed by central neck dissection and frozen section examination of jugular-carotid compartments. Median follow-up was 10.9 (range 0.69-33.05) years and median tumor size was 20 (range 2-60) mm. Papillary carcinoma was found in 96%, and follicular and Hürthle cell carcinoma in 2% of patients. Multifocal tumors were found in 50% and capsular invasion in 60% of patients. Lymphonodal metastases in either central or lateral neck compartments were found in 73% of patients. Multifocality and capsular invasion were significantly more frequent in patients less than 16 years of age (both p < 0.01). Median disease-free interval had not been reached and overall survival rate was 100%. Well-differentiated thyroid carcinoma in children and adolescents is characterized by a high rate of loco-regional aggressiveness, multifocality, capsular invasion, lymph node metastases and distant metastases at the time of diagnosis. Adequate surgical approaches should be performed for both primary and recurrent disease in young patients with well-differentiated thyroid carcinoma in order to achieve loco-regional disease control and longer disease-free survival.

Twenty-five years after Chernobyl: outcome of radioiodine treatment in children and adolescents with very high-risk radiation-induced differentiated thyroid carcinoma

CONTEXT

After severe reactor emergencies with release of radioactive iodine, elevated thyroid cancer risk in children and adolescents is considered the main health consequence for the population exposed.

DESIGN

We studied thyroid cancer outcome after 11.3 years' median follow-up in a selected, very high-risk cohort, 234 Chernobyl-exposed Belarusian children and adolescents undergoing postsurgical radioiodine therapy (RIT) in Germany.

INTERVENTIONS

Cumulatively 100 children with or (without; n = 134) distant metastasis received a median 4 (2) RITs and 16.9 (6.6) GBq, corresponding to 368 (141) MBq/kg iodine-131.

MAIN OUTCOME MEASURES

Outcomes were response to therapy and disease status, mortality, and treatment toxicity.

RESULTS

Of 229 patients evaluable for outcome, 147 (64.2%) attained complete remission [negative iodine-131 whole-body scan and TSH-stimulated serum thyroglobulin (Tg) < 1 μg /L], 69 (30.1%) showed nearly complete remission (complete response, except stimulated Tg 1-10 μg/L), and 11 (4.8%) had partial remission (Tg > 10 μg/L, decrease from baseline in radioiodine uptake intensity in ≥ 1 focus, in tumor volume or in Tg). Except for 2 recurrences (0.9%) after partial remission, no recurrences, progression, or disease-specific mortality were noted. One patient died of lung fibrosis 17.5 years after therapy, 2 of apparently thyroid cancer-unrelated causes. The only RIT side effect observed was pulmonary fibrosis in 5 of 69 patients (7.2%) with disseminated lung metastases undergoing intensive pulmonary surveillance.

CONCLUSIONS

Experience of a large, very high-risk pediatric cohort with radiation-induced differentiated thyroid carcinoma suggests that even when such disease is advanced and initially suboptimally treated, response to subsequent RIT and final outcomes are mostly favorable.

German Association of Endocrine Surgeons practice guideline for the surgical management of malignant thyroid tumors

INTRODUCTION

Over the past years, the incidence of thyroid cancer has surged not only in Germany but also in other countries of the Western hemisphere. This surge was first and foremost due to an increase of prognostically favorable ("low risk") papillary thyroid microcarcinomas, for which limited surgical procedures are often sufficient without loss of oncological benefit. These developments called for an update of the previous practice guideline to detail the surgical treatment options that are available for the various disease entities and tumor stages.

METHODS

The present German Association of Endocrine Surgeons practice guideline was developed on the basis of clinical evidence considering current national and international treatment recommendations through a formal expert consensus process in collaboration with the German Societies of General and Visceral Surgery, Endocrinology, Nuclear Medicine, Pathology, Radiooncology, Oncological Hematology, and a German thyroid cancer patient support organization.

RESULTS

The practice guideline for the surgical management of malignant thyroid tumors includes recommendations regarding preoperative workup; classification of locoregional nodes and terminology of surgical procedures; frequency, clinical, and histopathological features of occult and clinically apparent papillary, follicular, poorly differentiated, undifferentiated, and sporadic and hereditary medullary thyroid cancers, thyroid lymphoma and thyroid metastases from primaries outside the thyroid gland; extent of thyroidectomy; extent of lymph node dissection; aerodigestive tract resection; postoperative follow-up and surgery for recurrence and distant metastases.

CONCLUSION

These evidence-based recommendations for surgical therapy reflect various "treatment corridors" that are best discussed within multidisciplinary teams and the patient considering tumor type, stage, progression, and inherent surgical risk.

[Differentiated thyroid cancer in childhood]

Thyroid carcinoma is a rare disease in children, and is mostly of the papillary histological type. Lymph node metastases are frequent at diagnosis, being present in 23 to 74% of the cases and can reveal the cancer in about one fourth of cases. Lung metastases are present at initial diagnosis in 6 to 20% of cases. The main known risk factor for thyroid cancer is a previous history of radiation exposure. Treatment includes surgery with total thyroidectomy and lymph node dissection and radioiodine therapy in case of extensive disease and distant metastases. Life-long thyroxine treatment is given to all patients. Long term prognosis is favourable, but thyroid cancer related deaths have been reported some decades after initial treatment.

Spinal metastasis in thyroid cancer

BACKGROUND

Thyroid carcinoma generally responds well to treatment and spinal metastasis is an uncommon feature. Many studies have looked at the management of spinal metastasis and proposed treatments, plans and algorithms. These range from well-established methods to potentially novel alternatives including bisphosphonates and vascular endothelial growth factor (VEGF) therapy, amongst others.The purposes of this systematic review of the literature are twofold. Firstly we sought to analyse the proposed management options in the literature. Then, secondly, we endeavoured to make recommendations that might improve the prognosis of patients with spinal metastasis from thyroid carcinomas.

METHODS

We conducted an extensive electronic literature review regarding the management of spinal metastasis of thyroid cancer.

RESULTS

We found that there is a tangible lack of studies specifically analysing the management of spinal metastasis in thyroid cancer. Our results show that there are palliative and curative options in the management of spinal metastasis, in the forms of radioiodine ablation, surgery, selective embolisation, bisphosphonates and more recently the VEGF receptor targets.

CONCLUSIONS

The management of spinal metastasis from thyroid cancer should be multi-disciplinary. There is an absence; it seems, of a definitive protocol for treatment. Research shows increased survival with 131I avidity and complete bone metastasis resection. Early detection and treatment therefore are crucial. Studies suggest in those patients below the age of 45 years that treatment should be aggressive, and aim for cure. In those patients in whom curative treatment is not an option, palliative treatments are available.

Pediatric thyroid cancers: an Indian perspective

Pediatric thyroid cancer is a rare entity accounting for less than 5% of all thyroid cancers. This intriguing disease is characterized by advanced presentation, coupled with frequent lymph nodal metastases and often pulmonary metastases. It perhaps exhibits a distinct biology and behaviour, because in spite of its aggressiveness, survival is extremely good. This mandates meticulous treatment decisions that are well executed, because the complications of therapy in patients with good survival may spell prolonged morbidity. Being an unusual disease, it is unlikely that level I evidence guiding the management will come forth. There have been controversies regarding management, and the current consensus comes from large prospective studies. There have been only a few studies from India detailing pediatric thyroid cancers. In the current discussion, we review the existing evidence about pediatric thyroid cancers, and try to have an Indian perspective at the problem.

The treatment of differentiated thyroid cancer in children: emphasis on surgical approach and radioactive iodine therapy

Pediatric thyroid cancer is a rare disease with an excellent prognosis. Compared with adults, epithelial-derived differentiated thyroid cancer (DTC), which includes papillary and follicular thyroid cancer, presents at more advanced stages in children and is associated with higher rates of recurrence. Because of its uncommon occurrence, randomized trials have not been applied to test best-care options in children. Even in adults that have a 10-fold or higher incidence of thyroid cancer than children, few prospective trials have been executed to compare treatment approaches. We recognize that treatment recommendations have changed over the past few decades and will continue to do so. Respecting the aggressiveness of pediatric thyroid cancer, high recurrence rates, and the problems associated with decades of long-term follow-up, a premium should be placed on treatments that minimize risk of recurrence and the adverse effects of treatments and facilitate follow-up. We recommend that total thyroidectomy and central compartment lymph node dissection is the surgical procedure of choice for children with DTC if it can be performed by a high-volume thyroid surgeon. We recommend radioactive iodine therapy for remnant ablation or residual disease for most children with DTC. We recommend long-term follow-up because disease can recur decades after initial diagnosis and therapy. Considering the complexity of DTC management and the potential complications associated with therapy, it is essential that pediatric DTC be managed by physicians with expertise in this area.

Clinical presentation and clinical outcomes in Chernobyl-related paediatric thyroid cancers: what do we know now? What can we expect in the future?

Over the last 20 years, nearly 5000 cases of differentiated thyroid cancer have been diagnosed and treated in the regions of Russia, Ukraine and Belarus in young people previously exposed to the Chernobyl radioactive fallout during childhood. At diagnosis, 60-70% of the Chernobyl-related paediatric thyroid cancers had clinically evident cervical lymph node metastases (N1) and 10-15% had distant metastases (M1). Despite early reports suggesting that the paediatric thyroid cancer cases that developed after exposure to Chernobyl fallout were particularly aggressive, it now seems that the initial presentation and early clinical course of most of these cases are very similar to both non-radiation-associated paediatric thyroid cancers and thyroid cancers that arise after exposure to external beam irradiation. Over an average clinical follow-up period of about 10 years, the disease-specific mortality rate in these paediatric thyroid cancer cases that developed after the Chernobyl accident is quite low (1% or less). As would be expected in paediatric thyroid cancer, short-term recurrence rates range from 7 to 28% in published reports (mean 17%). However, long-term studies of paediatric thyroid cancer suggest that although the 30 year disease-specific mortality rate should be about 1%, the risk of developing structural disease recurrence is nearly 30% (of which 80% are expected to be locoregional recurrences and 20% are probably new distant metastases). Projected over 30 years of follow-up, a 1% disease-specific mortality in this cohort of 5000 patients would equate to about 50 deaths directly attributable to thyroid cancer. However, a 30% recurrence rate would also mean that about 1500 patients may develop a clinically meaningful recurrence that would need to be diagnosed and treated. It is imperative that we continue to work with our colleagues in Belarus, Ukraine and Russia to ensure that this large volume of patients destined to develop clinically significant recurrences are diagnosed and treated in a timely manner. Ready access to modern disease detection tools (serum thyroglobulin, postoperative neck ultrasonography, cytology/pathology support, and radioactive iodine scanning) and treatments (surgery for recurrent disease, radioactive iodine therapy) in their major academic centres are mandatory if we expect to achieve the excellent clinical outcomes that should be seen when paediatric thyroid cancer recurrence is diagnosed early and treated appropriately.

An individualized approach to the child with thyroid cancer

Children with differentiated thyroid cancer (DTC) often present with extensive disease that inclined clinicians in prior decades toward aggressive treatment including total thyroidectomy, radical neck dissection and universal prescription of radioactive iodine (RAI). Recent series with 40 years of follow-up have shown that fewer than 2% of children ultimately die from DTC, but they may have increased all-cause mortality from second malignancies that might be related to previous radiation exposure. In this article, we review data to support the notion that an individualized, risk-stratified approach to therapy should be used for children with DTC. Ideally this will provide aggressive therapy for those in whom aggressive treatment is warranted, but withhold aggressive and risk-associated therapy from those who are not likely to benefit.

Long-term outcome in 215 children and adolescents with papillary thyroid cancer treated during 1940 through 2008

BACKGROUND

Controversy exists regarding the aggressiveness of initial therapy in childhood papillary thyroid cancer (PTC). Few studies with long-term outcome exist and second primary malignancies have rarely been analyzed.

METHODS

We studied 215 PTC patients younger than 21 years old managed during 1940 through 2008. The patients were aged 3-20 year old (median age = 16 years); the median follow-up was 29 years. Recurrence and mortality details were taken from a computerized database.

RESULTS

Median primary tumor size was 2.2 cm. Six percent had distant metastases at presentation, 5% had incomplete tumor resection, 86% had nodes removed at initial surgery, and 78% had nodal metastases. After complete surgical resection, PTC recurred in 32% by 40 years. At 20 years, the recurrence rates at local, regional, and distant sites were 7, 21, and 5%, respectively. During 1940-1969, local and regional recurrence rates after unilateral lobectomy (UL) were significantly (P < 0.001) higher than after bilateral lobar resection (BLR). During 1950-2008 radioiodine remnant ablation (RRA) was administered within 18 months to 32%; it did not diminish the 25-year regional recurrence rate of 16% seen after BLR alone (P = 0.86). Only two fatal events from PTC occurred at 28 and 30 years, for a cause-specific mortality at 40 years of only 2%. All-causes mortality rates did not exceed expectation through 20 years, but from 30 through 50 years, the number of deaths was significantly (P < 0.001) higher than predicted. Fifteen of 22 deaths (68%) resulted from nonthyroid malignancy.

CONCLUSION

Survival from childhood PTC should be expected, but later death from nonthyroid malignancy is disconcerting. Seventy-three percent of those who died from nonthyroid malignancy had received postoperative therapeutic irradiation.

Differentiated thyroid carcinoma in pediatric patients: comparison of presentation and course between pre-pubertal children and adolescents

OBJECTIVE

To evaluate the clinical characteristics, course, and outcome of differentiated thyroid carcinoma (DTC) in pre-pubertal children compared with adolescents.

STUDY DESIGN

The records of 10 pre-pubertal and 17 pubertal patients in whom DTC was diagnosed and who were observed in our tertiary pediatric endocrine clinic were reviewed. Extension of tumor at presentation, treatment modality, course, and outcome were analyzed.

RESULTS

A positive family history of DTC was more prevalent in the pre-pubertal group (P = .037). At diagnosis, they had a greater degree of extrathyroid extension (P = .012), lymph node involvement (P = .009), and lung metastases (P = .009). The extent of surgery was similar in both groups, whereas the weight-adjusted radioiodine (I(131)) ablative dose was higher in the pre-pubertal group (P = .004). During the median follow-up of 5 years, the overall survival rate was 100% for both groups, with no significant difference in evidence of residual tumor after initial therapy or the recurrence rate.

CONCLUSION

DTC has a more aggressive presentation in pre-pubertal children. Rigorous initial surgical and I(131) treatment, followed by thyrotropin suppression, was found to result in an outcome similar to that achieved in the pubertal group.

The successful use of sorafenib to treat pediatric papillary thyroid carcinoma

BACKGROUND

Pediatric papillary thyroid cancer (PTC) typically presents with more advanced disease as compared with adults, yet the prognosis, even in the presence of distant metastatic disease, is usually excellent. Systemic therapies other than radioactive iodine (RAI) are rarely required. Sorafenib is an orally administered multi-kinase inhibitor that has shown promise in the treatment of adults with advanced thyroid cancer, but it has not yet been studied in children with this disease.

OBJECTIVE

Our objective is to present an adolescent with a progressive RAI-resistant PTC who was successfully treated with sorafenib.

PATIENT AND INTERVENTION

A 14-year-old girl had progressive lung metastases from PTC despite previous therapies with almost 400 mCi (131)I. Sorafenib was initiated at a starting dose of 200 mg twice daily and decreased to a maintenance dose of 200 mg daily due to side effects that developed within 3 weeks of treatment. After 67 days on the lower dose, there was a dramatic improvement in the lung metastases. The patient was monitored while continuing thyrotropin-suppressive therapy only. Minimal regrowth of the pulmonary metastases was observed, and a second treatment course of sorafenib 200 mg every other day was equally successful in achieving a clinical response. Thyroglobulin autoantibodies declined over the course of therapy and observation.

CONCLUSION

In the very rare case of the pediatric patient with progressive RAI-refractory PTC, for which no good systemic therapy exists, sorafenib may play an important role in the management of this disease.

Metastatic insular thyroid carcinoma in the pediatric patient

OBJECTIVES

The clinical history of a pediatric patient with metastatic insular thyroid carcinoma will be reviewed. Previously reported cases will be examined to allow for comparison of prognosis.

METHODS

A 4-year-old female with the complaint of chronic cough, progressive shortness of breath, and weight loss for 2 months underwent cervical lymph node biopsy. The biopsy revealed metastatic thyroid carcinoma. Preoperative imaging was suspicious for miliary metastatic spread to the lungs.

RESULTS

Surgical intervention included total thyroidectomy with bilateral paratracheal and modified radical neck dissections. The right internal jugular vein and recurrent laryngeal nerve were removed at the time of surgery because of gross tumor invasion. Final pathologic finding revealed papillary thyroid carcinoma with insular variant features and bilateral regional metastasis. Postoperatively, the patient underwent radioactive iodine I 131 treatment.

CONCLUSION

Pediatric metastatic insular thyroid carcinoma is an uncommon form of thyroid malignancy requiring aggressive surgical treatment and adjuvant radioactive iodine.

External beam radiation therapy for thyroid cancer

This article discusses the role of external beam radiotherapy (XRT) in the management of well-differentiated thyroid cancer (WDTC), medullary thyroid cancer, and anaplastic thyroid cancer. Although there are no randomized controlled studies on the use of XRT in thyroid cancer, evidence supports its use to treat gross disease after surgery or unresectable cancer and its use as an adjuvant after resection of a known high-risk disease in WDTC, and, to a lesser extent, in medullary thyroid cancer. The use of XRT for the palliation of symptomatic disease and recent advances in the technology of radiation delivery also will be discussed.

Pediatric pulmonary tumors: primary and metastatic

Pediatric pulmonary tumors are rare. There is often a significant delay in diagnosis of pulmonary tumors secondary to their rarity and nonspecific presenting physiologic and radiographic findings. A high index of suspicion in pediatric patients with recurrent or persistent pulmonary symptoms is of paramount importance in diagnosing pulmonary tumors at an early stage. Malignant pulmonary tumors are more frequently diagnosed than benign lesions, with metastatic cancers being the most common. Complete surgical resection remains the basis of therapy for primary lesions, and its role in secondary cancers is becoming more established. Adjuvant therapies are frequently employed depending on the precise tumor involved. Mortality rates vary greatly depending on tumor location, stage, and type.

Pulmonary metastasectomy in pediatric patients

This article describes the historical development of pediatric pulmonary metastasectomy but demonstrates that progress has been slow in understanding its proper applications. Because many pediatric metastatic tumors are rare, surgeons have grouped together patients of different histologies for the generation and analysis of case series. By examining tumor types individually, however, it is seen that certain histologies (adrenocortical carcinoma, alveolar soft part sarcoma, osteosarcoma) mandate surgical metastasectomy for patient survival. Other pediatric tumors (Wilms tumor, Ewing's sarcoma) are radiation sensitive, and the application of metastasectomy is controversial. In the case of still other types of tumor (neuroblastoma, differentiated thyroid cancer, rhabdomyosarcoma), metastasectomy is seldom performed except in highly unusual situations. Techniques for minimally invasive biopsy and for muscle-sparing thoracotomy are described for pediatric patients.

Thyroid nodules and cancers in children

Thyroid nodules are clinically evident in approximately 1% of children and about 30% of these are malignant. In addition to requiring appropriate surgery, thyroid hormone replacement in and follow-up monitoring of patients who are members of families with tumor syndromes must be studied for other components of these syndromes.

The management of advanced thyroid cancer

Although the prognosis of the majority of patients with thyroid cancer is excellent there are some patients with advanced thyroid cancer in whom the prognosis is poor. Such patients include: patients with locally invasive or recurrent differentiated thyroid cancer and medullary thyroid cancer, and all patients with anaplastic cancer. The management of patients with advanced thyroid cancer is reviewed with emphasis on the role of external beam radiotherapy.

Thyroid disease in northern Italian children born around the time of the Chernobyl nuclear accident

BACKGROUND

The Chernobyl nuclear accident of 1986 caused a dramatic increase in the incidence of thyroid cancers in exposed children in Belarus. Airborne radioactivity from the reactor spread over northern Italy, where rainout gave rise to low levels of radioactivity at ground level.

PATIENTS AND METHODS

As the latency between exposure to ionising radiation and development of thyroid cancer is thought to be about 10 years, in 1996/1997 all children born in 1985 and 1986 and attending school in an area of Milan, Italy were examined for thyroid nodules. A total of 3949 children were examined by two physicians blinded to the examination and diagnosis of the other. The children were to be reassessed in 2001/2002.

RESULTS

In total, 1% had palpable nodules. The nodule diagnoses were: Hurtle cell adenoma (one), thyroglossal duct cyst (one), thyroid cyst (four) and thyroiditis (four). The prevalence of thyroid disease in the cohort was indistinguishable from that of populations not exposed to radioactive pollution. Only 10 children re-presented for examination 5 years later; all were negative. The direct costs of the study were estimated at 21,200 Euros.

CONCLUSION

The high cost of the study in relation to reassuring lack of increase in thyroid nodule prevalence suggests that further studies are not justified.

Current Strategies for Surgical Management and Adjuvant Treatment of Childhood Papillary Thyroid Carcinoma

Childhood papillary thyroid carcinoma is associated with more locally aggressive and more frequent distant disease than its adult counterpart. Recurrence rates tend to be higher in children, but cause-specific mortality remains low. Optimal initial treatment of childhood papillary thyroid carcinoma should include total or near-total thyroidectomy and central compartment node clearance. Modified neck dissections should be performed for biopsy-proven lateral neck disease. Every effort should be made to maintain parathyroid and laryngeal nerve function. Radical neck dissections are to be avoided. Radioiodine remnant ablation (RRA), appropriate thyroid hormone suppressive therapy (THST), and judicious use of therapeutic doses of (131)I are applied to achieve a disease-free status, which is most often confirmed by negative neck ultrasonography, negative whole-body scan (either withdrawal or recombinant human thyroid-stimulating hormone-stimulated), and extremely low levels of serum thyroglobulin. Appropriate utilization of (131)I, THST, repeat surgery, external beam radiotherapy, and rarely chemotherapy may provide long-term palliation and some cures in patients with recurrent/persistent disease. Follow-up should be lifelong, and the care of children after age 17 should subsequently be transferred to adult-care endocrinologists with expertise in managing thyroid neoplasia. Optimal surgical management can be achieved if adequate operations are routinely carried out by "high-volume" thyroid surgeons with expertise in the care of children. Nowhere is a multidisciplinary approach (endocrinologists, surgeons, nuclear medicine physicians, pediatricians, pathologists, oncologists) more critical than in the long-term management of papillary thyroid carcinoma that presents during childhood.

Predictive Factors for Recurrence from a Series of 74 Children and Adolescents with Differentiated Thyroid Cancer

The influence of clinical and treatment factors on the risk of recurrence was analyzed from a retrospective series of 74 children and adolescents with thyroid cancer (55 girls, 19 boys; age 2-20 years). Two groups, comparable in terms of age, sex, and previous radiotherapy, were compared according to the presence (group 1) or absence (group 2) of cervical lymph nodes identified by palpation or ultrasonography. Total thyroidectomy (TT) with lymph node dissection (LND) was performed in the 19 group 1 patients, whereas in group 2 patients (n = 55) lobectomy was performed in 29, TT in 26, and LND in 7. Pathology studies showed papillary thyroid carcinoma in 95% of cases. In group 1, tumors were more frequently multifocal (89% vs. 16% in group 2), invasive with extension beyond the thyroid capsule (68% vs. 5% in group 2), and of the diffuse sclerosing variety (63% vs. 4% in group 2) (p < 0.001). With a median follow-up of 61 months, lymph node recurrence was seen in 53% of group 1 patients and in no patients in group 2. Three group 2 patients (10%) were reoperated for a local recurrence after lobectomy. Risk factors for reintervention were young age (< 15 years) (p < 0.01) and cervical lymph nodes (p < 0.001). Survivals without reintervention at 5 and 10 years were, respectively, 58% and 38% for group 1 and 94% and 90% for group 2 (p < 0.001). At the time of analysis, 68% of group 1 patients and 98% of group 2 patients were in remission. In conclusion, the presence of palpable cervical lymph nodes at diagnosis is associated with more invasive forms of malignancy and is a predictive factor of recurrence regardless of the extent of the initial surgery.

Thyroid carcinoma

Thyroid carcinomas are fairly uncommon and include disease types that range from indolent localised papillary carcinomas to the fulminant and lethal anaplastic disease. Several attempts to formulate a consensus about treatment of thyroid carcinoma have resulted in published guidelines for diagnosis and initial disease management. Multimodality treatments are widely recommended, although there is little evidence from prospective trials to support this approach. Surgical resection to achieve local disease control remains the cornerstone of primary treatment for most thyroid cancers, and is often followed by adjuvant radioiodine treatment for papillary and follicular types of disease. Thyroid hormone replacement therapy is used not only to rectify postsurgical hypothyroidism, but also because there is evidence to suggest that high doses that suppress thyroid stimulating hormone prevent disease recurrence in patients with papillary or follicular carcinomas. Treatment for progressive metastatic disease is often of limited benefit, and there is a pressing need for novel approaches in treatment of patients at high risk of disease-related death. In families with inherited thyroid cancer syndromes, early diagnosis and intervention based on genetic testing might prevent poor disease outcomes. Care should be carefully coordinated by members of an experienced multidisciplinary team, and patients should be provided with education about diagnosis, prognosis, and treatment options to allow them to make informed contributions to decisions about their care.

Evaluation and management of a solitary thyroid nodule in a child

Although an uncommon clinical entity, a pediatric patient with a solitary thyroid nodule requires a thorough assessment because of the increased incidence of thyroid carcinoma in this population. In the future, one may expect the widespread clinical use of genetic markers in identifying children, who are at risk for, or who have developed, thyroid carcinomas, with the hopes that these molecular markers will lead to the prevention, or earlier detection and cure, of these malignancies.

Well-differentiated carcinoma of the thyroid

Thyroid cancer will be diagnosed in more than 20,000 individuals in the United States in 2002. Approximately 16,000 of these patients will be women. During the same year, an estimated 1300 deaths from thyroid cancer are expected. The various types of thyroid cancer include papillary carcinoma, follicular carcinoma, Hurthle cell carcinoma, medullary carcinoma, anaplastic carcinoma, and thyroid lymphoma. Papillary, follicular, and Hurthle cell carcinoma are considered well-differentiated thyroid cancers and constitute the focus of this article.

Current controversies in the management of pediatric patients with well-differentiated nonmedullary thyroid cancer: a review

Current treatment strategies for pediatric patients with nonmedullary, well-differentiated thyroid carcinoma (WDTC) are derived from single-institution clinical cohorts, reports of extensive personal experience, and extrapolation of several common therapeutic practices for this tumor in adults. Because pediatric WDTC is an uncommon malignancy, the issues of its optimal initial and subsequent long-term treatment and follow-up remain controversial. Pediatric patients with WDTC can be divided into two groups: children younger than 10 years of age and teenagers/adolescents between 10 and 18 years of age because these groups have different recurrence and mortality rates. We hereby present our views and interpret them in the light of the pertinent literature. Our recommendations on treatment strategies are more relevant for younger children. After midpuberty, optimal treatment is adequately addressed in the relevant literature on adults. For the majority of patients, total/near-total thyroidectomy is currently recommended as the standard initial therapy for WDTC. This is commonly followed by administration of radioiodine (RAI; (131)I) therapy to destroy residual normal thyroid tissue (remnant). Routine (131)I remnant ablation has been shown to: (1). decrease the risk of local recurrences, (2) increase the sensitivity of subsequent diagnostic RAI whole-body scanning (WBS), and (3) render serum thyroglobulin (Tg) a highly sensitive marker for recurrent/residual disease during long-term follow-up. We recognize that the above practices are not universally adhered to in children and adolescents, because the risk stratification and intensity of applied therapeutic measures are influenced by institutional traditions and personal experience. In our view, aggressive initial management, followed by evaluations at regular intervals after thyroidectomy and (131)I remnant ablation, in conjunction with long-term thyroid hormone suppressive therapy (THST), result in decreased recurrence rates in pediatric patients with WDTC. Follow-up examinations should include a diagnostic RAI ((131)I or (123)I) WBS and measurement of serum Tg, both performed under conditions of TSH stimulation, as well as neck ultrasonography (US). Our strategy is corroborated by data from retrospective clinical cohort studies. In this malignancy, no evidence of disease (NED) status can be defined as the combination of a negative diagnostic WBS and the presence of undetectable or low serum Tg levels, both tested under TSH stimulation. These findings should be accompanied by the absence of anatomically definable disease by standard imaging modalities, e.g., neck US or chest computed tomography (CT). Although the long-term survival rates are good overall in this disease, selected patients may require further surgery or (131)I therapy for the eradication or clinical control of metastases. Finally, and importantly, because the duration of follow-up is lifelong, the care of children with prior diagnosis of WDTC should be transferred to an adult endocrinologist after they reach adulthood, even if they have achieved NED status by that time.

The spectrum of thyroid diseases in childhood and its evolution during transition to adulthood: natural history, diagnosis, differential diagnosis and management

In this contribution, we review current knowledge on the pathogenesis, diagnosis and differential diagnosis of thyroid disorders in childhood and adolescence, as well as present an update on therapy methods and management guidelines for these disorders. This overview is conceptually divided into two parts, one focusing on thyroid functional disorders, i.e. conditions leading to hyper- and hypothyroidism, and another one pertinent to structural abnormalities of the thyroid gland, i.e. nodular disorders and thyroid cancer. Currently, congenital hypothyroidism is diagnosed in a much more timely fashion rather than in the past, rendering hypothyroidism-related mental retardation and developmental deficits very rare in newborns and children and, hence, diminishing significantly its public health impact. At the same time, considerable advances have occurred in our understanding of the molecular basis of several genetic conditions affecting the thyroid gland in childhood, such as familial non-autoimmune hyperthyroidism, as well as of the pathways leading to thyroid neoplasia.

The development of breast carcinoma in women with thyroid carcinoma

BACKGROUND

Breast carcinoma and thyroid carcinoma are two malignancies that occur most commonly in women. An association between the incidence rates of thyroid and breast carcinoma in women after a diagnosis of the other malignancy has been suggested in a retrospective analysis of a single institution's tumor registry. In that study, an increased incidence of breast carcinoma in premenopausal women previously treated for thyroid carcinoma was observed.

METHODS

The purpose of this study was to investigate further this relation utilizing a large database, the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) database. The SEER database is maintained by the National Cancer Institute, and it represents 11 population-based cancer registries covering approximately 14% of the United States population. The study was a population-based retrospective cohort analysis using external comparisons. From 1973 to 1994, 365 women in the SEER database were identified as having both thyroid and breast carcinomas. The SEER database from 1973 to 1994 was utilized to calculate age specific and calendar year specific incidence rates for each year for thyroid and breast carcinomas. The expected number of second cancers for each age group, calendar year, and follow-up period were determined by multiplying these incidence rates by the age specific and calendar year specific number of person-years at risk. The risk ratio (RR) was calculated by dividing the observed by the expected number of second cancers. Statistical significance was determined by the Poisson test.

RESULTS

A total of 1,333,115 person-years were available for analysis. One hundred thirteen thyroid carcinoma cases were diagnosed after breast carcinoma cases (RR, 0.99; P = 0.576). Two hundred fifty-two breast carcinoma cases were diagnosed after thyroid carcinoma cases (RR, 1.18; P = 0.007). Premenopausal women (age 20-49 years) with an index thyroid carcinoma have a significantly increased risk of developing subsequent breast carcinoma (RR, 1.42; P = 0.001). Black premenopausal women with an index thyroid carcinoma do not have an increased risk of developing breast carcinoma, but the statistical power is lower due to low numbers. No women with index breast carcinoma have an increased risk of developing thyroid carcinoma.

CONCLUSIONS

Women with a history of thyroid carcinoma have a greater than expected risk of developing breast carcinoma. This risk is most pronounced in premenopausal white women. The implications of this observation with respect to breast carcinoma screening guidelines and thyroid carcinoma treatment guidelines deserve further investigation.