Recurrence and Complications in Pediatric and Adolescent Papillary Thyroid Cancer in a High-Volume Practice

Central lymph node ratio is an important recurrence prognostic factor for pediatric differentiated thyroid cancer

Background

The current risk stratification methods for Pediatric Differentiated Thyroid Carcinoma (DTC) are deemed inadequate due to the high recurrence rates observed in this demographic. This study investigates alternative clinicopathological factors, specifically the Central Lymph Node Ratio (CLNR), for improved risk stratification in pediatric DTC.

Methods

A retrospective review of 100 pediatric DTC patients, aged 19 or younger, treated between December 2012 and January 2021 at the First Affiliated Hospital of Guangxi Medical University was conducted. Clinicopathological variables were extracted, and univariate logistic regression identified factors correlated with recurrence. Kaplan-Meier (KM) survival analysis and subsequent statistical tests were used to assess the significance of these factors.

Results

The CLNR, with a cutoff value of 77.78%, emerged as a significant predictor of recurrence. Patients with a CLNR above this threshold had a 5.467 times higher risk of recurrence. The high CLNR group showed a higher proportion of male patients, clinically lymph node positivity (cN1), and extrathyroidal extension (ETE) compared to the low-risk group (p<0.05).

Conclusion

CLNR is a valuable predictor for recurrence in pediatric DTC and aids in stratifying patients based on Recurrence-Free Survival (RFS). For patients with a high CLNR, aggressive iodine-131 therapy, stringent TSH suppression, and proactive postoperative surveillance are recommended to mitigate recurrence risk and facilitate timely detection of recurrent lesions.

Recurrence and survival for patients with thyroid carcinoma in the pediatric age group in the Emirate of Abu Dhabi: retrospective analysis of a multicentre cohort

OBJECTIVES

Pediatric thyroid cancer represents 2.3 % of thyroid cancers, and its long-term outcome data are sparse. There have not been studies in the UAE delineating its epidemiology, clinical and histological characteristics, and follow-up outcomes. We aimed to evaluate the clinical-pathological behavior, recurrence and survival rates in pediatrics with all types of thyroid cancer in the UAE.

METHODS

Multicentre retrospective chart review analysis of pediatric patients with thyroid carcinoma from January 2010 to December 2020 in Abu Dhabi, UAE.

RESULTS

Thirty-four patients were included, 85 % being females. Papillary thyroid carcinoma (PTC) was the commonest type of thyroid cancer (88 %) vs. follicular thyroid carcinoma (FTC) (11.8 %). Almost half of our patients had a multifocal disease, 26 % had lymphovascular invasion (LVI), and 21 % had extrathyroidal extension (ETE). There were no mortalities during follow-up. 85 % of patients exhibited complete remission, while 15 % of patients showed evidence of progressive residual or recurrent disease. One patient had metastasis to lymph nodes and lungs.

CONCLUSIONS

There were similar trends of incidence, sex prevalence, and histopathological patterns as the ones observed internationally. Potential risk factors in our population include a family history of thyroid cancer and obesity. The lower rate of ETE, LVI, metastasis, and recurrence indicates a possibly less aggressive disease.

Impact of lateral cervical lymph node metastasis on lung metastasis in pediatric thyroid cancer: A correlation study

BACKGROUND

Thyroid cancer (TC) frequently manifests with lung metastases in the pediatric population, occurring at a significant rate of 30 %. This study aims to evaluate the impact of regional patterns of cervical lymph node metastases on lung metastases in pediatric TC.

METHODS

Retrospective analysis was conducted on data from pediatric TC patients spanning the years 2000 to 2018. We compared the rates of lymph node metastasis (LNR), the number of lymph node metastases, and the number of dissected lymph nodes in the central and lateral cervical regions between patients with and without lung metastases. Statistical methods were employed to adjust for confounders during hypothesis testing.

RESULTS

A total of 227 pediatric patients, with a median age of 15.12 ± 2.84 years, were included in the study. Of these, 202 (89 %) exhibited LN metastasis, with 40(17.62 %) patients presenting with lung metastasis. Patients with lung metastases were found to be younger (13.40 ± 3.11 vs. 15.50 ± 2.64, p < 0.001), had larger primary tumor diameters (3.49 ± 1.98 vs. 2.31 ± 1.45, p < 0.001), and exhibited a higher number of lymph node metastases (23.40 ± 10.75 vs. 14.65 ± 13.16, p < 0.001). Notably, in patients with LN metastases, the presence of >12 lateral cervical lymph node metastases emerged as a significant risk factor for lung metastases. Among children with metachronous lung metastases, the median time to detection of lung metastases was 43 (12-132) months, and they appeared to receive a greater proportion of radioactive iodine (RAI) treatment compared to those with synchronous lung metastases.

CONCLUSION

Lateral cervical lymph node metastasis independently predicts the likelihood of lung metastases in pediatric TC. Furthermore, our findings emphasize the importance of thorough examination of the lungs during follow-up, particularly when the number of metastatic lateral cervical lymph nodes exceeds 12.

Risk factors for recurrence of differentiated thyroid carcinoma in children and adolescents: A retrospective cohort study

This study aimed to provide a recent clinical evaluation of the outcome of treatment and the predictors of recurrence for Chinese children and adolescents with differentiated thyroid carcinoma (DTC). This is a retrospective cohort study at the Yunnan Cancer Hospital from May 2002 to August 2021. We analyzed several risk factors related to the recurrence of DTC in children and adolescents. The Chi-square test, Kaplan-Meier log-rank tests, and Cox regression analysis were used in the statistical analysis. A P-value <.05 was considered statistically significant. A total of 103 patients were enrolled, including 68 girls (66.0%) and 35 boys (34.0%) with a median age of 18 years (range: 7-20 years). All enrolled patients received standard treatment. Children (≤14years) tended to have multifocality and higher levels of thyroid imaging reporting and data system, higher pN stage, and higher American Thyroid Association (ATA) pediatric risk compared with adolescents (P < .05). The chief complaints and clinical treatment differed between children and adolescents. During a follow-up of 6 to 239 months (average 74.7 months, median 59 months), all patients survived, but recurrence occurred in 22 patients (22.4%). The disease-free survival rates at 1, 2, 5, and 10 years were 91.2%, 78.4%, 77.1%, and 77.1%, respectively. Univariate Cox regression and log-rank tests showed that positive preoperative thyroglobulin level, bilaterality, extrathyroidal extension, high pT/pN/pM stage, and high ATA pediatric risk were the risk factors for DTC recurrence in children and adolescents. Multivariate Cox regression found that extrathyroidal extension and ATA pediatric risk were independent risk factors for the recurrence of DTC in children and adolescents. Additionally, among the 38 cases with cN0 stage, one who had bilateral, and multifocal thyroid nodules experienced recurrence, while the remaining 37 cases with cN0 stage had no recurrence. In conclusion, compared with adolescents, children present with more highly malignant disease and are more prone to metastasis. The significant risk factors associated with the recurrence of DTC in children and adolescents were positive preoperative thyroglobulin level, bilaterality, high pT/pN/pM stage, extrathyroidal extension, and high ATA pediatric risk, with the latter 2 being independent risk factors. The surgical approach for cN0 patients should be personalized taking into account invasive features.

Clinical features of thyroid cancer in paediatric age. Experience of a tertiary centre in the 2000-2020 period

PURPOSE

To describe the clinical features of a paediatric cohort affected by differentiated thyroid cancer (DTC) followed in a tertiary Department of Paediatric Endocrinology.

METHODS

Clinical data of 41 patients affected by DTC in the 2000-2020 period were reviewed.

RESULTS

The main risk factor was autoimmune thyroiditis (39%). Cytological categories were TIR3b in 39%, TIR4 in 9.8%, TIR5 in 51.2%. After total thyroidectomy, radioiodine treatment was performed in 38 subjects (92.7%). ATA low-risk category was assigned in 11 (30.5%), intermediate-risk category in 15 (41.7%), and high-risk category in 10 patients (27.8%). Age at diagnosis was 15.1 ± 0.92 years in low-risk category, 14.7 ± 0.59 in intermediate-risk category, 11.7 ± 0.89 years in high-risk category (p = 0.01). TIR3b was manly observed in low-risk class (63.6%), while TIR5 was mainly reported in intermediate and high-risk class (60 and 80% respectively) (p = 0.04). Post-surgery stimulated thyroglobulin was increased in high-risk class (407.8 ± 307.1 ng/ml) [p = 0.04]. Tumour size was larger in high-risk category (42.6 ± 2.6 mm), than in low and intermediate-risk categories (19.4 ± 3.5 mm and 28.5 ± 3.9 mm, respectively) (p = 0.008). Patients in intermediate and high-risk categories displayed more tumour multifocality (60 and 90% respectively) (p < 0.005). Disease relapse was mainly observed in high risk category (40%, p = 0.04).

CONCLUSION

DTC in childhood is more aggressive than in adults, but the overall survival rate is excellent. The therapeutic approach is still heterogeneous, especially in low-risk category. Further studies are needed to standardise management and reduce disease persistence in childhood.

Prepubertal Children with Papillary Thyroid Carcinoma Present with More Invasive Disease Than Adolescents and Young Adults

Introduction: Pediatric papillary thyroid carcinomas (PTCs) are more invasive than adult PTCs. No large, contemporary cohort study has been conducted to determine whether younger children are at higher risk for advanced disease at presentation compared to adolescents. We aimed to describe pediatric PTC and contextualize its characteristics with a young adult comparison cohort. Methods: The National Cancer Database was interrogated for pediatric and young adult PTCs diagnosed between 2004 and 2017. Clinical variables were compared between prepubertal (≤10 years old), adolescent (11-18 years old), and young adult (19-39 years old) groups. Multivariable logistic regression modeling for independent predictors of metastases was conducted. A subanalysis of microcarcinomas (size ≤10 mm) was performed. Results: A total of 4860 pediatric (prepubertal n = 274, adolescents n = 4586) and 101,159 young adult patients were included. Prepubertal patients presented with more extensive burden of disease, including significantly larger primary tumors, higher prevalence of nodal and distant metastases, and increased frequency of features such as lymphovascular invasion, and extrathyroidal extension (ETE). Prepubertal age was an independent predictor of positive regional nodes (adjusted odds ratio [AOR] = 1.36 [95% confidence interval {CI} 1.01-1.84], p = 0.04) and distant metastatic disease (AOR = 3.12 [CI 1.96-4.96], p < 0.001). However, there was no difference in survival between groups (p = 0.32). Prepubertal age independently predicted lymph node metastases for microcarcinomas (AOR = 2.19 [CI 1.10-4.36], p = 0.03). Prepubertal (n = 41) versus adolescent (n = 937) patient age was associated with gross ETE (p = 0.004), even with primary tumors ≤1 cm in size. Conclusions: Patients aged <11 years old present with more advanced disease than adolescents, with a higher likelihood of nodal and distant metastatic disease at time of diagnosis, although survival is high. Prepubertal children undergo more extensive treatment, likely reflective of more invasive disease at the outset, even in the setting of a subcentimeter primary tumor.

Fourteen years old as the best age cutoff to differentiate prepubertal from pubertal papillary thyroid carcinoma

BACKGROUND

It is unclear whether differences in clinical presentation and/or prognosis exist between prepubertal papillary thyroid cancer (PTC) and pubertal PTC. At present, there is a lack of definition for the appropriate cutoff age to define prepubertal PTC.

METHODS

This study retrospectively reviewed 227 pediatric PTC patients (aged ≤18 years) who underwent initial surgery from March 2000 to December 2018. The median duration of follow-up was 85 months (range, 8-258).

RESULTS

The age range was basically linearly related to multiple risk factors, such as T3-T4 disease, distant metastasis. Age (p = 0.032) was an independent risk factor for recurrence and persistent disease. Patients aged <14 years had obviously higher rates of extensive disease. The 10-year disease-free survival (DFS) rate of patients aged <14 years was 59.5% and that of patients aged ≥14 years was 82.6% (p = 0.004).

CONCLUSIONS

Fourteen years of age may be an appropriate cutoff to differentiate prepubertal PTC from pubertal PTC.

The intercorrelation among CCT6A, CDC20, CCNB1, and PLK1 expressions and their clinical value in papillary thyroid carcinoma prognostication

BACKGROUND

CCT6A promotes several carcinomas' growth and invasion in multiple ways, and it relates to CCNB1 and PLK1 through its interaction with CDC20 via protein-protein interaction bioinformatics. This study aimed to explore the intercorrelation among CCT6A, CDC20, CCNB1, and PLK1, and their association with tumor features and prognosis in papillary thyroid carcinoma (PTC) patients.

METHODS

CCT6A, CDC20, CCNB1, and PLK1 expressions in 186 tumor and 30 non-tumor specimens from PTC patients were determined by immunohistochemical (IHC). Clinical features, disease-free survival (DFS), and overall survival (OS) were retrieved.

RESULTS

CCT6A, CDC20, CCNB1, and PLK1 expressions were upregulated in tumor tissues compared with non-tumor tissues (all p < 0.001). CCT6A expression positively correlated with CDC20, CCNB1, and PLK1 expressions; besides, CDC20 expression positively associated with CCNB1 and PLK1 expressions, and CCNB1 expression was also positively related to PLK1 expression (all p < 0.05). Moreover, elevated tumor CCT6A expression was correlated with extrathyroidal invasion (p = 0.015), higher pT stage (p < 0.001), pN stage (p = 0.046), and pTNM stage (p = 0.042); while tumor CDC20, CCNB1, and PLK1 expressions only correlated with some of these indexes (most p < 0.05). Notably, CCT6A and CDC20 high expressions predicted worse DFS and OS (all p < 0.05); CCNB1 positive expression only predicted poor DFS (p = 0.044) but not OS (p = 0.152); however, PLK1 expression failed to predict these two indexes (both p > 0.05). After adjustment using multivariate Cox's regression, CCT6A expression (high vs. low) independently estimated shorter DFS (p = 0.010) and OS (p = 0.006).

CONCLUSION

CCT6A, CDC20, CCNB1, and PLK1 are intercorrelated, and they exhibit certain prognostic values in PTC patients.

Factors associated with postoperative hypocalcemia following thyroidectomy in childhood

BACKGROUND

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

PROCEDURE

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

RESULTS

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

CONCLUSIONS

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

Prophylactic Central Neck Dissection to Improve Disease-Free Survival in Pediatric Papillary Thyroid Cancer

Background

Pediatric PTC is a rare disease. Although, the prognosis is excellent and the mortality rate is low, the role of prophylactic central neck dissection is still the subject of debate. The aim was to evaluate both the role and safety of prophylactic central neck dissection (CND) in managing pediatric papillary thyroid cancer (PTC), especially in respect of disease-free survival (DFS).

Patients and Methods

In this retrospective study, we collected 54 pediatric cN0 PTC patients (≤ 18 years of age) who were treated from January 2014 to January 2021 at a high-volume thyroid surgery center. Patients were divided into two groups based on the status of prophylactic CND. We analyzed the factors related to the clinicopathological features and recurrence of PTC in children.

Results

Of the 54 cN0 patients, 35 underwent prophylactic CND and 19 patients did not undergo prophylactic CND. The two groups were similar in clinical and pathologic features, such as age, gender, tumor size, multifocal status, and follow-up time. The average DFS was 84.4 ± 2.7 months. Log-rank tests on Kaplan-Meier curves revealed that age, gender, tumor size, multifocality, and extrathyroid extension did not relate to DFS time. Furthermore, DFS time was not affected by the extent of thyroidectomy (p=0.07) or RAI treatment (p=0.21). Prophylactic CND was found to increase DFS time for pediatric patients with cN0 PTC (p = 0.003). There was no statistically significant difference in complications such as transient hypocalcemia (p=0.15) and transient recurrent laryngeal nerve injury (p=0.37) between the prophylactic CND group and the no-prophylactic CND group.

Conclusion

Prophylactic CND was found to be associated with increased DFS and not with increased rates of complications after surgery.

Surgical treatment of pediatric and adolescent papillary thyroid cancer: a retrospective study of 54 patients in a single center

OBJECTIVE

In 2015, American Thyroid Association (ATA) issued the first version of Management Guidelines for Children with Thyroid Nodules and Differentiated Thyroid Cancer. The purpose of this study is to evaluate whether the ATA pediatric guidelines recommended surgical approach for the patient can be applied to surgical treatment of pediatric PTC in China.

METHOD

From April 2012 to December 2020, clinical data of children (≤18 years) with PTC consecutively admitted and treated with initial surgery in the study's department were retrospectively reviewed.

RESULTS

The authors found that the central lymph node metastasis (CLNM) rate was significantly higher than that in the lateral neck (83.33 % vs 62.96%, χ² = 5.704, p = 0.017) .The lymph node metastasis rate was significantly lower in cN1b (-) patients than in cN1b (+) patient (55.00% vs 100.00%, χ² = 15.263, p = 0.000); Meanwhile, the CLNM and LLNM rates of ipsilateral were significantly higher than those of contralateral central compartment (83.33༅vs 57.41༅%, χ² = 8.704, p = 0.003). Lymph nodes of 51 lateral lymph node dissection (LND) were analyzed, which revealed the LNM rate of cN1b (-) patients was significantly lower than that of cN1b (+) patients (55.00% vs. 100.00%, χ² = 15.263, p = 0.000).

CONCLUSION

Children and adolescents have a higher rate of lymph node metastasis at the time of diagnosis. TT should be conducted in the majority of children with PTC. CND should be routinely performed; therapeutic LND is recommended for children with cN1b (+).

Relationship Between Thyroid Autoantibodies and Recurrence of Papillary Thyroid Carcinoma in Children and Adolescents

Background

Numerous studies reported connection between papillary thyroid carcinoma (PTC) and thyroid autoantibody in adults, but few of them have investigated whether there is a similar link in children and adolescents. The purpose of this research was to explore the relationship between clinicopathological features, prognosis and preoperative thyroid peroxidase antibody (TPOAb) as well as thyroglobulin antibody (TgAb) status in children and adolescents with PTC.

Methods

This study retrospectively reviewed 179 patients of PTC who underwent a thyroidectomy from January 2000 to June 2021 at Tianjin Medical University Cancer Hospital. We compared preoperative TgAb and TPOAb status with the clinicopathological features and prognosis of children and adolescents with PTC in different age groups.

Results

Patients with positive preoperative TPOAb and TgAb had lower recurrence rate in the younger group (P = 0.006, 0.047, respectively). Patients with positive TPOAb preoperatively had normal level of preoperative Tg and less cervical LNM than patients with negative TPOAb in children and adolescents (P < 0.05). Positive TPOAb preoperatively of PTC patients had a longer median DFS (113.4 months) than negative TPOAb (64.9 months) (P = 0.009, log-rank). Univariate analyses showed age, maximal tumor size, T stage, multifocality, lateral LNM and N staging were predictors for cancer recurrence in children and adolescents (P<0.05). Cox regression analysis found younger age (HR 0.224, P < 0.001), lateral LNM (HR 0.137, P = 0.010), N stage (HR 30.356, P < 0.001) were independent risk factors for recurrence.

Conclusions

Our study found that presence of preoperative TPOAb and TgAb could serve as novel prognostic factors for predicting recurrence of PTC in children.

Impact of Lung Metastasis versus Metastasis of Bone, Brain, or Liver on Overall Survival and Thyroid Cancer-Specific Survival of Thyroid Cancer Patients: A Population-Based Study

We investigate the impact of lung metastasis versus metastasis of bone, brain, or liver on overall survival (OS) and thyroid cancer-specific survival (TCSS) in patients with thyroid cancer (TC). Therefore, de-identified SEER 18 registry data of primary TC patients diagnosed between 2010 and 2016 were analyzed. The primary outcome was the prognosis of TC patients with lung metastasis compared with other sites. The secondary outcomes included the prognosis comparison between patients with and without surgery and between single and multiple metastasis sites. Isolated lung metastasis was associated with worse OS and TCSS than bone metastasis (both p < 0.05) and was associated with worse OS than liver metastasis (p = 0.0467). Surgery performed either for the primary or distant site was associated with better OS and TCSS in patients with metastasis of lung or bone (p < 0.05). Isolated lung metastasis was related to better OS and TCSS than lung−liver, lung−brain, and lung−other multiple metastases. The multivariable analysis revealed that age < 55 years, surgery to the primary site, and to the distant site(s) were associated with better outcomes, while T4 and Tx were associated with worse outcomes. Nevertheless, it revealed that the other race (i.e., any race other than white, black, or unknown) and male gender were associated with better TCSS only (p < 0.05). Isolated lung metastasis is associated with a worse prognosis in TC patients compared with bone or liver metastasis. Surgery performed either for the primary or distant site(s) is associated with better survival outcomes in TC patients with metastasis of lung or bone.

Aggressiveness of Differentiated Thyroid Carcinoma in Pediatric Patients Younger Than 16 years: A Propensity Score-Matched Analysis

Background

The biological behavior of thyroid cancer in children has been known to be different from that in adults. We sought to understand the differences between DTC presentation in pediatric (<16 years) and adult patients, to guide better prognosis and clinical treatments.

Methods

This retrospective study included 48 pediatric patients younger than 16 years who underwent initial thyroid surgery and were diagnosed with DTC between January 1992 and December 2014 at Yonsei University in Seoul, South Korea. For a 1:4 propensity score-matched analysis, adult patients with matched sex and cancer size were included.

Results

The mean age was 12.54 ± 3.01 years. Total thyroidectomy (70.8%) without lateral lymph node dissection (47.9%) was the most commonly performed surgery. Central (73.9%) and lateral neck node metastases (62.5%) were common; distant metastasis was observed in 2 (4.2%) patients and recurrence occurred in 11 (22.9%). In propensity score-matched analysis, central lymph node metastasis and lateral neck node metastasis were significantly more frequent in pediatric patients. Symptoms were more common in the pediatric group than in the adult group (p < 0.001). In stratified cox regression, pediatric patients were more likely to experience recurrence [HR 5.339 (1.239–23.007)]. In stratified log-rank analysis, recurrence-free survival was significantly different between the adult and pediatric groups (p = 0.0209).

Conclusion

DTC in the pediatric group revealed more aggressive patterns than in the adult group with the same cancer size. Central lymph node metastasis and lateral neck node metastasis were more frequent. Stratified log-rank analysis revealed that recurrence was significantly higher in pediatric patients than in matched adult patients.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSION

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

Diverse Oncogenic Fusions and Distinct Gene Expression Patterns Define the Genomic Landscape of Pediatric Papillary Thyroid Carcinoma

Pediatric papillary thyroid carcinoma (PPTC) is clinically distinct from adult-onset disease. Although there are higher rates of metastasis and recurrence in PPTC, prognosis remains highly favorable. Molecular characterization of PPTC has been lacking. Historically, only 40% to 50% of childhood papillary thyroid carcinoma (PTC) were known to be driven by genomic variants common to adult PTC; oncogenic drivers in the remainder were unknown. This contrasts with approximately 90% of adult PTC driven by a discrete number of variants. In this study, 52 PPTCs underwent candidate gene testing, followed in a subset by whole-exome and transcriptome sequencing. Within these samples, candidate gene testing identified variants in 31 (60%) tumors, while exome and transcriptome sequencing identified oncogenic variants in 19 of 21 (90%) remaining tumors. The latter were enriched for oncogenic fusions, with 11 nonrecurrent fusion transcripts, including two previously undescribed fusions, STRN-RET and TG-PBF. Most fusions were associated with 3' receptor tyrosine kinase (RTK) moieties: RET, MET, ALK, and NTRK3. For advanced (distally metastatic) tumors, a driver variant was described in 91%. Gene expression analysis defined three clusters that demonstrated distinct expression of genes involved in thyroid differentiation and MAPK signaling. Among RET-CCDC6-driven tumors, gene expression in pediatric tumors was distinguishable from that in adults. Collectively, these results show that the genomic landscape of pediatric PTC is different from adult PTC. Moreover, they identify genomic drivers in 98% of PPTCs, predominantly oncogenic fusion transcripts involving RTKs, with a pronounced impact on gene expression. Notably, most advanced tumors were driven by a variant for which targeted systemic therapy exists. SIGNIFICANCE: This study highlights important distinctions between the genomes and transcriptomes of pediatric and adult papillary thyroid carcinoma, with implications for understanding the biology, diagnosis, and treatment of advanced disease in children.

Clinical Heterogeneity of Differentiated Thyroid Cancer between Children Less than 10 Years of Age and Those Older than 10 Years: A Retrospective Study of 70 Cases

OBJECTIVES

The objectives of this study were to explore the clinical heterogeneity of differentiated thyroid cancer (DTC) between prepubertal children and adolescents and guide clinical treatment.

METHODS

A retrospective study included patients with DTC aged ≤19 years in Beijing Children's Hospital from June 2014 to June 2019. All patients were enrolled and divided into 2 subgroups based on the threshold age of 10 years, namely the childhood group (CG) (≤10 years old); and the adolescent group (AG) (between 10 and 19 years old). The χ² test and Fisher's exact test were used to estimate the effect of risk factors in the 2 age groups. Multivariate binary logistic regression models were conducted to assess the recurrent risk factors.

RESULTS

Seventy cases of DTC were included with an average age of 9.94 ± 2.88 years, including 35 in CG and 35 in AG. The most common clinical manifestation was a painless mass in the neck, accounting for 77.1% (54/70) of patients. Compared with the AG, the CG was more likely to have lymph node metastasis (p = 0.022) and distant metastasis (p = 0.041). The CG was more likely to have extrathyroidal extension (p = 0.012) and had a significantly higher recurrence rate than the AG (p = 0.040). Age was an independent variable predictive of recurrence (p = 0.0347).

CONCLUSION

Regional invasiveness, cervical lymph node metastasis, and distant metastasis of DTC were more likely to occur in children ≤10 years old. Meanwhile, children ≤10 years old with DTC were more likely to have recurrence than adolescent's postsurgical treatment. Thus, children younger than 10 years of age with DTC should be treated more aggressively.

Total Thyroidectomy vs Thyroid Lobectomy for Localized Papillary Thyroid Cancer in Children: A Propensity-Matched Survival Analysis

BACKGROUND

Current guidelines recommend total thyroidectomy (TT) and radioablation for most papillary thyroid cancer (PTC) in children. These guidelines have been criticized as aggressive, especially for early-stage PTC, as it likely does not influence patient survival and results in life-long thyroid hormone replacement. We sought to study whether the extent of thyroidectomy (TT vs thyroid lobectomy [TL]) influences overall and disease-specific survival in children with localized PTC.

METHODS

The National Cancer Database and the Surveillance, Epidemiology, and End Results registries were queried. Patients 18 years or younger with low-risk PTC between 2004 and 2016 were included. Using a 1:1 propensity score matching, patients who underwent TT were matched for age, sex, race, year of diagnosis, and tumor size with a similar cohort of patients who underwent TL. Primary end points were overall survival and disease-specific survival.

RESULTS

There were 3,500 patients identified as surgically treated for PTC, of which 1,325 patients met inclusion criteria for matching. Three hundred and twenty-six patients were matched. One hundred and sixty-three patients had TT; 140 were female and mean age was 16 years (interquartile range [IQR] 13 to 17 years). One hundred and sixty-three patients had TL; 140 were female and mean age was 16 years (IQR 14 to 17 years). Median follow-up was 5.0 years (IQR 2.8 to 8 years) and 8.3 years (IQR 3.6 to 14.4 years) in the National Cancer Database and Surveillance, Epidemiology, and End Results cohorts, respectively. There was no statistically significant difference in overall survival or disease-specific survival in patients with PTC < 4 cm, regardless of whether patients underwent TT or TL (p = 0.32 for National Cancer Database registry and p = 0.67 for Surveillance, Epidemiology, and End Results registry).

CONCLUSIONS

This study suggests that the extent of thyroidectomy does not influence survival for pediatric patients with early-stage PTC and that TL might be adequate in this patient population.

Risk Factors and Prediction Model for Lateral Lymph Node Metastasis of Papillary Thyroid Carcinoma in Children and Adolescents

Purpose

Papillary thyroid carcinoma (PTC) in children and adolescents is prone to lateral lymph node metastasis (LNM), which is a high-risk factor for recurrence. However, few studies focused on identifying risk factors and establishing prediction models for lateral LNM of PTC in children and adolescents.

Patients and Methods

We retrospectively reviewed consecutive cases of children and adolescents with PTC undergoing thyroidectomy and cervical lymph node dissection between January 2009 and December 2019. The demographics and clinicopathologic features were collected and analyzed.

Results

A total of 102 children and adolescents with PTC were enrolled in our study; 51 of whom had lateral LNM (50%). After adjusting for other risk factors, the independent risk factors for lateral LNM were multifocality (odds ratio [OR]: 6.04; 95% confidence interval [CI]: 1.653–22.092; p=0.007), tumor size (OR: 1.752; 95% CI: 1.043–2.945; p=0.034), and the number of central LNM (OR: 1.23; 95% CI: 1.028–1.472; p=0.023). The formula of the combined predictor is: Multifocality + 0.31 × Tumor size + 0.115 × Number of central LNM. The area under the receiver operating characteristic curve of multifocality, tumor size, number of central LNM, and the combined predictor was 0.706, 0.762, 0.748, and 0.855, respectively. When the value of the combined predictor was ≥2.2744, lateral LNM could be predicted. The sensitivity and specificity of the predicted value were 82.4% and 74.5%, respectively.

Conclusion

The independent risk factors for lateral LNM in children and adolescents with PTC were multifocality, tumor size, and the number of central LNM. The prediction model can better predict the presence of lateral LNM.

Management of Differentiated Thyroid Carcinoma in Pediatric Patients

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

Pediatric differentiated thyroid carcinoma: An update from the APSA Cancer Committee

BACKGROUND

Differentiated thyroid carcinomas (DTCs) are rare in young children but represent almost 10% of all malignancies diagnosed in older adolescents.

METHODS

This article reviews the recent literature describing surgical therapeutic approaches to pediatric DTC, associated complications, and long-term recurrence and survival outcomes.

RESULTS

Similar to adult thyroid cancers, pediatric DTCs are more common in females and are associated with thyroid nodules, family history of thyroid cancer, radiation exposure, iodine deficiency, autoimmune thyroid disease, and genetic syndromes. Management of thyroid cancers in children involves ultrasound imaging, fine needle aspiration, and surgical resection with treatment decisions based on clinical and radiological features, cytology and risk assessment.

CONCLUSIONS

Total thyroidectomy and compartment based resection of clinically involved lymph node basins form the cornerstone of treatment of DTC. There is an evolving literature regarding the use of molecular genetics to inform treatment strategies and the use of targeted therapies to treat iodine refractory and surgically unresectable progressive disease.

TYPE OF STUDY

Summary review.

LEVEL OF EVIDENCE

This is a review article of previously published Level 1-5 articles that includes expert opinion (Level 5).