Surgical experience in children with differentiated thyroid carcinoma

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.

Long-term outcome of differentiated thyroid cancer in children and young adults: risk stratification by ATA criteria and assessment of pre-ablation stimulated thyroglobulin as predictors of disease persistence

PURPOSE

Differentiated thyroid cancer (DTC) has an increasing incidence in childhood and adolescence but long-term outcome data are limited. We aimed to identify possible risk factors associated with disease persistence, with special focus on the usefulness of ATA risk stratification system and pre-ablation stimulated thyroglobulin (Tg) levels.

METHODS

We retrospectively studied 103 patients, 79 females (76.7%), aged 15.6 ± 3.2 years (range 5-21 years) who underwent total thyroidectomy for DTC. Patients were classified by ATA risk stratification criteria as low, intermediate, and high risk for recurrence. All, except five with papillary microcarcinoma, received radioactive iodine (RAI) treatment.

RESULTS

At diagnosis, 44.7% of patients had cervical lymph node and 7.8% pulmonary metastases. Amongst the 72 patients with long-term follow-up data, 31.9% had persistent disease. Lymph node as well as pulmonary metastases and increased pre-ablation stimulated thyroglobulin (Tg) levels were associated with persistent disease. The risk of persistent disease was significantly higher in both the intermediate- (OR 17.95; 95% CI 2.66-120.94, p < 0.01) and high-risk (OR 17.65; 95% CI 4.47-69.74, p < 0.001) groups. ROC curve analysis showed that a pre-ablation Tg level higher than 14 ng/ml had a sensitivity of 94.7% to predict persistence, corresponding to a positive (PPV) and negative predictive values (NPV) of 66.7% and 93.8%, respectively.

CONCLUSIONS

ATA risk stratification was validated in our population of children and young adults with DTC. Moreover, pre-ablation stimulated Tg levels of <14 ng/ml were associated with a low risk of long-term persistence and may therefore serve as a marker to identify patients who may need less intensive surveillance.

Long-term follow-up of differentiated thyroid carcinoma in children and adolescents

Objectives The aims were to analyze the clinical features, response to treatment, prognostic factors and long-term follow-up of children and adolescents with differentiated thyroid carcinoma (DTC). Methods Eighty patients with DTC were studied retrospectively. All underwent total or near-total thyroidectomy, and in 75 cases, ablative iodine therapy was recommended. Patients were assessed periodically by tests for serum thyroglobulin levels and whole-body iodine scans. Age, gender, initial clinical presentation, histology, tumor stage, postoperative complications, radioiodine treatment protocol, treatment response, thyroglobulin (Tg), recurrence and long-term disease progression were evaluated. Results Seventy patients completed >2 years of follow-up (23 males, 47 females; median age: 14 years; range: 3-18 years). Sixty-two patients showed papillary DTC and eight, follicular DTC. Sixty-five percent presented nodal metastasis and 16%, pulmonary metastasis at diagnosis. Six months after first radioiodine treatment, 36.2% of patients were free of disease. Seven recurrences were documented. At the end of follow-up, overall survival was 100%, and 87.2% of patients were in complete remission. Nine patients had persistent disease. We found a significant association between stage 4 and persistent disease. Hundred percent of patients with negative Tg values at 6 months posttreatment were documented free of disease at the end of the follow-up. The analysis of disease-free survival based on radioiodine treatment protocols used showed no statistically significant differences. Conclusions DTC in children and adolescents is frequently associated with presence of advanced disease at diagnosis. Despite this, complete remission was documented after treatment in most cases, with a good prognosis in the long-term follow-up. Negative posttreatment thyroglobulin and stage 4 at diagnosis were significant prognostic variables.

Hurthle cell carcinoma in childhood: A retrospective analysis of five cases and review of pediatric literature

BACKGROUND

the available studies on Hurthle cell carcinoma (HCC) in pediatric age are scarce and based on isolated case reports. Aims of the present study were to review the available pediatric literature on HCC (2000-2019), to describe the cohort of children with this cancer histotype, and to estimate its relative prevalence in pediatric age.

PROCEDURE

We retrospectively reconstructed an HCC course in five patients < 19 years who were identified in our departments during the period 2000-2019, and we reviewed the available pediatric studies on this differentiated thyroid cancer (DTC) variant.

RESULTS

HCC occurred with a relative prevalence of 5.8% at a median chronological age of 12.5 years. None of HCC patients exhibited, at diagnosis, thyroid dysfunction, extensive lateral neck disease, or distant metastases, and all showed a persistent remission over time. Three patients showed, at diagnosis, antecedents of other diseases (Hashimoto's thyroiditis, neurofibromatosis type 1, and osteosarcoma).

CONCLUSIONS

(1) In childhood, the relative prevalence of HCC among different thyroid cancer histotypes is 5.8%, that is close to the one previously reported both in the general population and in other less numerous children's cohorts; (2) HCC may develop even early, at the age of 7; (3) in childhood, HCC does not seem to have a more aggressive behavior when compared with other DTC histotypes; (4) antecedents of other diseases are not infrequent in the history of children with HCC.

Thyroid Cancer in Children: Management and Outcome Experience of a Referral Center

OBJECTIVE: To shed light on the discrepancy between the advanced stage at presentation and high recurrence rate of well-differentiated thyroid cancer in children and the overall good survival.

DESIGN AND METHODS: The files of 75 children with well-differentiated thyroid cancer treated from 1954 to 2001 in a major tertiary-care hospital were reviewed for disease course, management, and outcome.

RESULTS: Sixty patients (80%) had positive neck metastases with involvement of central compartment lymph nodes in all, lateral neck nodes in 36, and distant metastases in 4. Sixty-seven patients underwent total thyroidectomy with adjuvant radioiodine treatment and 8 underwent hemithyroidectomy; all had concomitant neck treatment. The rate of local (5%) and neck (9%) recurrence was similar to the total rate reported in adults. Total thyroidectomy led to a significantly lower recurrence rate (7.5%) than hemithyroidectomy (38%; P < 0.005). Type of neck dissection did not affect recurrence or appearance of distant metastases. All deaths (n = 2) were due to distant metastases, whereas 30% of adult deaths are due to local or neck disease.

CONCLUSIONS: The treatment of choice for well-differentiated thyroid cancer in young patients is total thyroidectomy. Neither regional disease at presentation nor recurrences affect survival.

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.

Evaluation and management of the pediatric thyroid nodule

Thyroid nodules are commonly diagnosed in adults. Although rare in children, the risk for thyroid cancer is much higher in the pediatric population compared with adults. Presenting as either a solitary nodule or a multinodular goiter, thyroid nodular disease in children requires a thorough workup that includes a detailed clinical examination comprised of prior history of thyroid disease in the patient or in their family, history of radiation exposure, careful palpation of the thyroid and lymph nodes, blood tests, ultrasonography, and cytological assessment. Thyroid surgery is the gold-standard treatment for pediatric thyroid nodules; nonetheless, the extent of surgery remains controversial. Because surgery is not without risk, the decision matrix necessitates focus on the benefits of surgery for the child contingent upon all the preoperative exams. New diagnostic technology such as molecular testing with fine needle aspiration biopsy may help distinguish between benign and malignant lesions while potentially decreasing surgery for benign disease. The objective of this review is to summarize new concepts in clinical disease management of nodular thyroid disease in the pediatric population, including patient history, medical examination, and diagnosis workup.

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.

Differentiated thyroid carcinoma of children and adolescents: 27-year experience in the yonsei university health system

Thyroid carcinomas are uncommon in childhood and adolescence. The aim of this study was to analyze clinical features and clinical outcomes of thyroid cancer in the pediatric population treated in the Yonsei University Health System. From September 1982 to June 2009, 90 patients (75 females, 15 males; female:male ratio of 5:1) with differentiated thyroid carcinoma were identified in our institute. The mean age at diagnosis was 15.8 yr old (range 4.8-19.9 yr). Cervical masses were most common clinical manifestations at diagnosis in 65 patients (72.2%). Forty-two patients underwent less than total thyroidectomy and 18 patients underwent total thyroidectomy. Thirty patients (33.3%) had lateral neck lymph node metastasis and seven patients (7.8%) had lung metastasis at the time of surgery. Among the 90 patients, recurrence occurred in 14 patients (15.5%). Mean follow-up period for patients with differentiated thyroid carcinoma was 81.6 months (13-324 months). No patients died of differentiated thyroid carcinoma. Patients with differentiated thyroid carcinoma who were < 20-yr-of-age were present with aggressive local disease and a high frequency of lymph node and distant metastasis. It is recommended that pediatric thyroid cancer should be managed mostly using proper surgical approach with thyroidectomy and lymph node dissection when indicated.

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.

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.

Utilization of total thyroidectomy for differentiated thyroid cancer in children

PURPOSE

Recent recommendations suggest that total thyroidectomy (TT) is the surgical management of choice for differentiated thyroid cancer in children. The objective of this study is to assess trends in extent of surgical resection for differentiated thyroid cancer in children over the past two decades and to identify patient, tumor or hospital factors associated with use of TT.

PATIENTS AND METHODS

Of 8,013 patients (aged 0-21 years) with differentiated thyroid cancer from the National Cancer Data Base (1985-2007), 5,933 (74%) underwent TT. Trends in extent of surgery were examined. Logistic regression was used to identify factors that predict use of TT.

RESULTS

Use of TT increased from 50.6% in 1985 to 84% in 2007 (P < 0.001). Patients were more likely to undergo TT if they had higher household income or had private insurance (P = 0.002 and P = 0.037). Patients were more likely to undergo TT if they had larger tumors or if there were nodal metastases present at time of resection (both P < 0.001). After adjusting for patient and tumor factors, patients treated at high-volume or Children's Oncology Group hospitals were more likely to undergo TT than patients treated at low-volume or non-Children's Oncology Group hospitals (P < 0.001).

CONCLUSIONS

Overall utilization of TT in children with differentiated thyroid cancer has steadily increased over the past 23 years in the USA. Variations in use of TT are not only related to tumor factors including size and nodal involvement, but also are also related to socioeconomic and hospital factors, demonstrating disparities in care.

Treatment strategy of papillary thyroid carcinoma in children and adolescents: clinical significance of the initial nodal manifestation

BACKGROUND

Risk factors and treatment strategy in younger patients with papillary thyroid carcinoma are still controversial.

METHODS

We reviewed 120 consecutive papillary thyroid carcinoma patients younger than 20 years who underwent initial surgery between 1977 and 2004 (14 male and 106 female subjects; mean age, 16.3 years; mean follow-up, 11.6 years). Outcomes were evaluated initially, and risk factors for disease-free survival (DFS) were analyzed statistically. Cox proportional multivariate analysis revealed that initial nodal manifestation (P < .001, hazard ratio 2.97) was the most statistically significant risk factor for DFS. The outcomes were then compared between four subgroups on the basis of the initial nodal manifestation and node dissection: 17 patients in group A (no lymphadenopathy, no or only prophylactic central dissection), 30 patients in group B (no lymphadenopathy, prophylactic modified neck dissection, MND), 46 patients in group C (nonpalpable lymphadenopathy detected by radiological or operative findings, therapeutic MND), and 27 patients in group D (palpable lymphadenopathy, therapeutic MND).

RESULTS

Subtotal/total thyroidectomy and radioactive iodine therapy were performed for 47.1 and 0% in group A, 33.3 and 0% in group B, 43.4 and 10.9% in group C, and 85.1 and 48.1% in group D, respectively. In groups A, B, C, and D, 0%, 3.3%, 28.3%, and 48.1% developed recurrence, respectively (P < .001). DFS Kaplan-Meier curves differed significantly among the four subgroups (P < .0005).

CONCLUSIONS

Initial nodal manifestation is useful to predict DFS in younger papillary thyroid carcinoma patients. Our findings will be beneficial to determine the treatment strategy. Conservative therapy is considered acceptable for patients without risk factors.

Diagnosis and management of pediatric endocrine neoplasms

PURPOSE OF REVIEW

To guide the clinician in the diagnostic evaluation of endocrine neoplasms, to distinguish between benign and malignant and determine when surgical referral is indicated.

RECENT FINDINGS

Thyroid nodules are uncommon but malignant in as many as 27% of patients. Fine needle aspiration should be considered in adolescents, in which accuracy is as high as 90%; surgical resection should be undertaken in all preadolescents (<13 years) with a thyroid nodule. Prognosis for most primary thyroid malignancies is favorable. Primary hyperparathyroidism is rare and due to an adenoma in up to 70% of patients. Surgical resection carries a cure rate of 95% with the use of intraoperative parathyroid hormone assays. Adrenal neoplasms cover a wide spectrum of disorder. They are functional in 95% of patients and require a thorough diagnostic evaluation prior to surgical resection. Malignant lesions of the adrenal gland carry a poor prognosis when complete surgical resection cannot be achieved. Carcinoids are rare neuroendocrine neoplasms, primarily of the appendix, associated with carcinoid syndrome in 10% of patients. The indolent course warrants aggressive surgical control.

SUMMARY

Endocrine neoplasms are unusual in the pediatric population. Their presence should raise concern about a multiple endocrine neoplasia syndrome and appropriate diagnostic and endocrine work-up. Most neoplasms will require surgical resection.

The therapeutic management of differentiated thyroid cancer

BACKGROUND

The management of thyroid cancer is difficult because the tumors comprise a wide range of biologic behaviors, from small papillary thyroid microcarcinomas that pose little or no threat to survival for the patient, to anaplastic thyroid cancers that are arguably the most lethal tumor. Although it may be difficult initially to determine at which end of the prognostic spectrum a patient resides, one can ordinarily estimate a patient's risk for tumor recurrence and mortality based on a triad of features as simple as the patient's age at the time of diagnosis, the tumor stage at presentation, and its initial response to therapy. While staging systems are available to assist in the management process, all are inexact and leave wide gaps in the treatment plan for a given patient. This is largely because randomized controlled trials are lacking as a result of the low incidence and generally favorable prognosis of the disease. As a practical matter, it may sometimes be difficult to reassure a patient, given the generally favorable prognosis of this group of tumors, knowing that without adequate therapy some become unexpectedly aggressive and recur years after initial management. The treatment of these tumors rests on a fine balance of providing care that reflects the anticipated course of the disease without overtreating the patient or providing reassurance that is unfounded.

OBJECTIVE

To outline the treatment strategy for patients with differentiated thyroid cancer based on the available literature and to guide clinicians through a management algorithm utilizing patient and tumor characteristics.

METHODS

This review is limited to the treatment of patients with differentiated thyroid cancer - papillary and follicular thyroid cancer - and the standard therapy required for the majority of patients.

RESULTS/CONCLUSION

The treatment of differentiated thyroid cancer requires a multidisciplinary approach, involving an experienced surgeon, radiologists and an endocrinologist. There are many unanswered questions in the management algorithm and ongoing research is needed to further define the best treatment strategy for patients with differentiated thyroid cancer.

Management of low-risk differentiated thyroid cancer

OBJECTIVE

To summarize the definitions of and management recommendations for low-risk thyroid cancer made by the American and European Thyroid Associations and synthesize this information with the recent literature, including systematic evaluations of tumor staging systems guiding therapy.

METHODS

The American Thyroid Association and European Thyroid Association guidelines were compared and pertinent literature since 2005 was reviewed.

RESULTS

Of papillary thyroid microcarcinomas (PTMC), up to 50% breach the thyroid capsule, 64% have lymph node metastases, up to 43% are multifocal, and as many as 2.8% have distant metastases. Locoregional and distant recurrences are, respectively, as high as 5.9% and 1.5%. As many as 1 in 4 patients with a papillary thyroid carcinoma 1.5 cm or smaller develop persistent disease. Cancer-related mortality rates are usually less than 1%, but are as high as 2% in some reports. Tumor staging systems are too inaccurate to guide therapy.

CONCLUSION

It is unlikely that many patients will forgo treatment after understanding their risk, especially when total thyroidectomy and radioiodine (131I) therapy can reduce the PTMC recurrence or persistence disease rate to zero. Preoperatively diagnosed PTMC should be treated with total or near-total thyroidectomy, regardless of tumor size. For very low-risk patients with unifocal PTMC smaller than 1 cm that is removed by chance during surgery to treat benign thyroid disease, lobectomy alone without 131I therapy may be sufficient therapy if there are no concerning histologic features and no tumor extension beyond the thyroid, metastases, history of head and neck irradiation, or positive family history--any of which requires total or near-total thyroidectomy and remnant ablation with 30 mCi.

Differentiated Pediatric Thyroid Cancer: Correlates With Adult Disease, Controversies in Treatment

The biologic behavior of differentiated thyroid cancer can differ between adults and children, especially in those children younger than 10 years of age. Unlike adults, young children typically present with advanced disease at diagnosis. Despite this, children respond rapidly to therapy and have an excellent prognosis that is significantly better than that of their adult counterparts with advanced disease. In contradistinction to adults, children with thyroid cancer also have higher local and distant disease recurrences with progression-free survival of only 70% at 5 years, mandating life-long surveillance. Although thyroid cancer is the most common carcinoma in children, overall incidence is low, a factor that has prevented performance of a controlled, randomized, prospective study to determine the most efficacious treatment regimen in this age group. So, although extensively investigated, treatment of pediatric patients with differentiated thyroid cancer remains controversial. This article reviews the current controversies in the treatment of pediatric differentiated thyroid cancer, focusing on issues of optimal initial and subsequent therapy as well as that of long-term follow-up. Our approach to treatment is presented. In so doing, similarities and differences between adults and children with differentiated thyroid cancer as regards unique considerations in epidemiology, diagnosis, staging, treatment, therapy-related late effects, and disease surveillance are presented. The expanding use of and appropriate roles for thyrogen and fluorine-18-fluorodeoxyglucose positron emission tomography in disease evaluation and surveillance will be addressed.

Childhood thyroid cancer in Belarus, Russia, and Ukraine after Chernobyl and at present

Thyroid cancer in children is usually rare, but in the individuals exposed to radiation risk of disease increases considerably. After the Chernobyl accident in 1986, an over 10-fold maximal elevation in the incidence of thyroid cancer was registered about a decade later, cumulatively resulting in more than a thousand of newly diagnosed cases in children who lived in the territories of Belarus, Russia, and Ukraine affected by radioactive fallouts. Experience from the epidemic substantially promoted knowledge in clinical pediatric oncology, pathology and basic sciences. This article overviews epidemiology, clinical features, results of treatment and follow-up of childhood patients with radiation-induced Chernobyl thyroid cancer in comparison to sporadic cases diagnosed at present. In addition, we discuss general issues of pathology and molecular findings in childhood thyroid carcinomas.

Carcinoma de tireóide na infância e adolescência

Aproximadamente 10% das neoplasias de tireóide aparecem abaixo dos 21 anos e representam 3% das neoplasias da infância, com predomínio em meninas (2F:1M). São papilíferos em 90% casos e mais freqüentemente bilaterais, multifocais e de maior dimensão. Invasão de cápsula e metástases ganglionar ou pulmonar são mais freqüentes que no adulto. O efeito carcinogênico da radiação é especialmente importante na criança pré-púbere. Em 5% dos casos de PTC existe história familial. Genes como o RET/PTC, RAS e BRAF estão habitualmente envolvidos na gênese do processo. A apresentação clínica pode ser nódulo cervical (90% casos) sem que represente um fator de pior prognóstico. O US e a PAAF são procedimentos diagnósticos valiosos. O tratamento deve ser cirúrgico (tireoidectomia total com esvaziamento ganglionar) seguido de PCI e radioterapia ablativa. A substituição com L-tiroxina deve objetivar a supressão crônica do TSH. O prognóstico ao longo prazo é melhor que no adulto. A quantificação da Tg plasmática também é útil na detecção da doença residual.

Management of paediatric thyroid carcinoma: recent experience with recombinant human thyroid stimulating hormone in preparation for radioiodine therapy

BACKGROUND

Thyroid carcinoma in children is rare and raises unique management issues. Although metastatic disease is more common in this age group, prognosis remains good with appropriate treatment. The aim of the study was to report recent experience in the management of differentiated thyroid carcinoma in children, especially in the use of radioiodine after recombinant human thyroid stimulating hormone (rhTSH) stimulation.

METHODS

Eight patients, aged 5-17 years (five were boys) presented following total thyroidectomy for thyroid carcinoma between May 2003 and June 2005. Seven had papillary carcinoma and one had follicular carcinoma. Five had known lymph node metastases and one had pulmonary metastases at presentation. Four patients had previously received therapeutic irradiation for malignancy. All eight underwent diagnostic iodine scans, seven with rhTSH stimulation. Seven went on to receive radioiodine treatment as hospital inpatients, comanaged by the paediatric and nuclear medicine units. The dosage of 131I ranged from 1.5 to 3.7 x 10(9) Bq. All except one were prepared by rhTSH stimulation.

RESULTS

Seven of eight patients had significant uptake in the neck on diagnostic scan and two had pulmonary abnormalities. Six of seven evaluable patients achieved complete thyroid ablation. Both patients with pulmonary abnormalities had scan resolution, although one of them only after a second radioiodine treatment. All patients had thyroxine replacement in doses to suppress TSH and all remain alive and well at time of carrying out this study.

CONCLUSION

Optimal management of paediatric thyroid carcinoma necessitates a multidisciplinary approach. Radioiodine therapy under rhTSH is an effective and safe adjuvant treatment in this special subgroup.

Comprehensive clinical assessment of 740 cases of surgically treated thyroid cancer in children of Belarus

OBJECTIVE

A retrospective study was designed to evaluate the results of surgical treatment and follow-up data in thyroid cancer patients less than 15 years old at the time of surgery.

SUMMARY BACKGROUND DATA

Pediatric thyroid carcinomas have a high rate of lymph nodal and distant metastases. Risk factors for recurrences and postoperative morbidity have not been assessed yet in a representative series.

METHODS

The group included 740 pediatric patients with thyroid cancer. Total thyroidectomy was performed in 426 (57.6%), lobectomy in 248 (33.5%), subtotal thyroidectomy in 58 (7.8%) cases, and 8 patients (1.1%) underwent partial lobectomy.

RESULTS

The mean follow-up period was 115.8 months (range, 1.5-236.4 months). Recurrence was diagnosed in 204 cases (27.6%), including 73 local relapses (9.9%), 90 distant metastases (12.2%), and a combination of local and distant recurrences in 41 (5.5%) patients. Multivariate statistical assessment revealed the following independent parameters significantly associated with the risk of recurrent nodal disease: a young age at diagnosis, multifocal carcinomas, N1 status, and lack of neck lymph node dissection. For lung metastases, the significant risk factors were female gender, young age at diagnosis, and presence of symptoms. The observed 5- and 10-year survival for the entire group was 99.5% and 98.8%, respectively. Postoperative hypoparathyroidism was significantly associated with multifocal tumors, central compartment removal, and ipsilateral dissection.

CONCLUSIONS

Total thyroidectomy followed by radioiodine therapy is an optimal treatment strategy that makes it possible to achieve a cure in a vast majority of pediatric patients with differentiated thyroid carcinomas. Risk of recurrence is strongly associated with tumor stage, extent of surgery, the young patient's age, and presence of symptoms at diagnosis.

Thyroid and parathyroid disease in children

Although diseases of the thyroid and parathyroid glands are relatively uncommon in children, the implications of missed diagnoses can be severe. This review describes the embryology, anatomy, and physiology of the thyroid and parathyroid glands, and focuses on significant benign and malignant pathologies of these glands.

Papillary thyroid carcinoma of childhood and adolescence: a 30-year experience at the Istituto Nazionale Tumori in Milan

BACKGROUND

Survival rates are reportedly excellent for papillary thyroid carcinomas (PTCs) in childhood/adolescence, despite their strong tendency to spread. The aim of this study was to verify this assumption in a single-institution series spanning a 30-year period with a very long follow-up.

PROCEDURE

From 1968 to 2001, 74 cases of thyroid carcinoma were collected. The papillary histological type was confirmed in 42 cases with available slides; we recorded the sex, age at diagnosis, age of menarche, tumor side and size, TNM/pTNM classification, multicentricity, vascular invasion, type of surgery, post-operative complications, post-surgical therapies and outcome up to May 31, 2004.

RESULTS

The female/male ratio was 2.2; pT4, pN1 and M1 cases were 52%, 95%, and 12% (four in lungs and one in bone), respectively. Total thyroidectomy was performed in 33 patients, hemithyroidectomy in 8, and a biopsy in 1 inoperable case. Nine patients (21%) relapsed, six in the cervical lymph nodes and three in the lungs. After a median follow-up of 189 months, all patients were alive, two of them with evidence of disease. Overall and progression-free survival curves were independent of sex, age, TNM/pTNM classification, or type of surgery. Overall survival was also independent of recurrence.

CONCLUSIONS

Unlike its adult counterpart, PTC of childhood and adolescence is a cancer with a high frequency of spread, but an excellent outcome irrespective of sex, age at diagnosis, TNM/pTNM classification, type of surgery, recurrence. Since pediatric PTCs proved highly responsive to hormone manipulation, it is worth considering a different therapeutic approach from adult cases.

Prophylaktische Chirurgie der Schilddrüse

Early diagnosis for thyroid carcinoma, potentially before neoplastic transformation has taken place, would allow preventive and thus curative surgical intervention. Identifying and characterizing the RET proto-oncogene as the disease-causing gene for hereditary medullary thyroid carcinoma and then establishing a genotype-phenotype correlation served as the prerequisite for the risk-adapted prophylactic surgical approach practised today. Carriers of RET mutations associated with very aggressive tumour behaviour should be subjected to prophylactic thyroidectomy within the 1st year of life. For individuals harbouring less virulent types of mutations, prophylactic intervention is recommended at 5-20 years. Although genetic research on hereditary nonmedullary thyroid cancer is still in progress, initial results indicate the need of prophylactic surgical treatment also for this subgroup of thyroid neoplasia.

Pediatric thyroid cancer

BACKGROUND AND OBJECTIVE

The treatment of pediatric thyroid cancer evokes considerable controversy. The extent of surgery and role of postoperative radioactive iodine are not clearly defined. We analyzed the behavior of pediatric thyroid cancers and its management.

METHODS

Eighty-three patients, from 1964-2000, were identified by a search of our database. The clinical course of 26 patients was not evaluated because of inadequate follow-up and the remaining 57 patients were included in the final survival analysis. These 26 patients were included for analyses of epidemiological data.

RESULTS

There were 27 males and 56 females. Cervical lymphadenopathy was a common presentation (57.8%). The predominant histology was papillary carcinoma (57%). Sixteen patients (19.2%) had pulmonary metastases at presentation. Patients with cervical nodes had a significantly higher incidence of pulmonary metastasis compared to those who presented with thyroid nodule (P = 0.037). Five patients (31.2%) with pulmonary metastases had a negative chest X-ray and were detected only on the radioiodine scan. At median follow-up of 64 months, all 57 patients were alive, 10 with disease and 47 disease free.

CONCLUSION

Despite its advanced stage at presentation, pediatric thyroid cancer is associated with an excellent prognosis. We advocate total thyroidectomy and radioactive iodine as the best management option as the incidence of pulmonary metastases is high.

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 surgery in children and adolescents

Authors present 114 children and adolescents of the total 3865 patients that underwent surgery on the Department of Otorhinolaryngology and Head and Neck Surgery, 1st Faculty of Medicine, Charles University, Prague, Department of Otorhinolaryngology of IPVZ, Prague because of a thyroid disease in years 1991-2000. The male/female ratio in the group was 1:6.5, 16 (13.9%) males and 99 (86.1%) females. For non-malignant disease, the male/female ratio was 1:6.5 and for malignant disease, it was 1:5.4. Thyroid surgery was indicated for non-malignant disease in 82 (71.9%) cases--11 males and 71 females. Most frequently it was indicated because of Graves-Basedow and Hashimoto toxicosis--in 39 children (34.2%), in 5 children (4.4%) for toxic adenoma. Because of the polynodular goiter surgery was indicated in 13 cases (11.4%), in 22 cases (19.3%) for mononodular goiter. Three girls (2.6%) were recommended for surgery because of Hashimoto thyreoiditis and for mechanic syndrome in diffuse goiter one girl (0.9%). Malignant tumor was found in 32 children (28.1%)--5 males and 27 females. Most frequent histological type was papillary cancer--in 25 cases (21.9%). Follicular cancer was diagnosed in four cases (3.5%) and medullar cancer in three cases (2.6%). TNM classification in children and adults is summarized in Table 1. Surgery was carried out in two children with distant metastases (lung localization). In both children the pre-disease stage lasted more than 12 months. The first manifestation of the disease was a finding of enlarged and palpable nodes on the neck. The authors summarize indications for surgery of thyroid diseases in children and adolescents. A treatment of the thyroid gland is a teamwork. Indication for surgery is carried out by a pediatric endocrinologist in cooperation with a surgeon specialized in thyroid surgery. The possible identification of the recurrent laryngeal nerve by a surgery microscope is an unquestionable advance. Children and adults should be centralized into health-care centers capable not only of surgery, but also of endocrinology care. In children with a malignant disease there is a need for cooperation with a pediatric oncologist and a following oncological treatment on a nuclear medicine department. The authors summarize the information about today's thyroid surgery care possibilities for children and adolescents. They point out the differences in indications and the decision about extent of surgery in children and adolescents.