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

Age Stratification and Prognostic Factor Analysis in Pediatric Differentiated Thyroid Cancer

OBJECTIVES

Differentiated thyroid cancer (DTC) is rare in the pediatric population. It remains unclear whether younger children are at greater risk of more aggressive disease. We aimed to identify prognostic factors for aggressive pediatric DTC and to define an appropriate age stratification.

METHODS

This retrospective cohort study included all patients aged 18 years or less who were treated for DTC between 1985 and 2021 in a tertiary medical center and were followed up for a minimum of 1.5 years after treatment.

RESULTS

Seventy-eight patients were included, all diagnosed with papillary thyroid carcinoma: 30 (38.5%) low-risk, 21 (26.9%) intermediate-risk, and 27 (34.6%) high-risk according to the American Thyroid Association (ATA) risk stratification. The mean duration of follow-up was 11.8 ± 7.8 years. No evidence of disease was documented in 52 patients (66.7%) at 1-year post-treatment and 64 patients (82.1%) at the end of follow-up. On analysis by age, evidence of disease at 1-year post-treatment was found in 66.7% of children younger than 11 years, compared to 25.4% of older children (p = 0.002). There was no significant difference by age in evidence of disease at the last follow-up (p = 0.453). Patients aged <11 years at diagnosis were associated with more aggressive disease features on histopathologic examination, metastatic disease, and high ATA risk level. Patients aged <8 years were associated with more frequent bilateral disease and extrathyroidal extension.

CONCLUSION

Pediatric DTC patients who are younger than 11 years at diagnosis have more aggressive disease features and a lower early remission rate than older patients. Nevertheless, their long-term outcome is satisfactory.

LEVEL OF EVIDENCE

4-retrospective cohort study Laryngoscope, 134:4818-4825, 2024.

Pathologic Characteristics and Surgical Outcomes of Pediatric Versus Adult Well-Differentiated Thyroid Cancer

OBJECTIVE

Despite the rising incidence of pediatric differentiated thyroid cancer (DTC), postoperative outcomes for such tumors have not been well-characterized. The objective of this study was to compare pathologic tumor characteristics and treatment outcomes for pediatric and adult patients with DTC.

STUDY DESIGN

Retrospective case-control study.

SETTING

National database.

METHODS

Pediatric (<18 years old) and adult (≥18 years old) patients who underwent surgery for DTC in the National Cancer Database (2004-2020) were included. Multivariable logistic, negative binomial, and linear regressions were used to compare pathologic tumor characteristics, treatment characteristics, and short-term surgical outcomes.

RESULTS

337,864 patients with DTC met the study eligibility criteria; 3584 (1.1%) were pediatric patients and 334,280 (98.9%) were adults. After adjustment, pediatric patients were found to have higher rates of pathologic T upstaging (adjusted odds ratio [ORadj]: 1.40, 95% confidence interval [CI]: 1.23-1.59), N upstaging (ORadj: 2.53, 95% CI: 2.23-2.88), and extrathyroidal extension (ORadj: 1.58, 95% CI: 1.29-1.94), compared to adult patients. Pediatric patients were also more likely to receive neck dissection (ORadj: 2.80, 95% CI: 2.55-3.07) and radioactive iodine (ORadj: 1.42, 95% CI: 1.30-1.55). Pediatric patients had higher rates of positive surgical margins (ORadj: 1.25, 95% CI: 1.11-1.41) and 30-day readmissions (ORadj: 1.26, 95% CI: 1.00-1.58) than adult patients.

CONCLUSION

These findings demonstrate that pediatric DTC is associated with more aggressive disease presentations, more radical treatment, and worse short-term surgical outcomes compared to DTC in adults. Pediatric DTC should be considered a unique clinical entity that requires personalized evaluation and multidisciplinary treatment by specialized providers.

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.

Stimulated thyroglobulin and diagnostic 131-iodine whole-body scan as a predictor of distant metastasis and association with response to treatment in pediatric thyroid cancer patients

INTRODUCTION

Differentiated thyroid carcinoma (DTC) is a rare oncological disease in the pediatric population, presenting with a more aggressive form. Stimulated thyroglobulin (sTg) and the 131-iodine whole-body scans (WBSs) are known adult markers related to the presence of distant metastasis. Little is known about their roles in the pediatric population.

PURPOSE

To evaluate sTg levels and diagnostic WBS (DxWBS) as predictors of distant metastasis after thyroidectomy and to correlate with the response to treatment at the end of follow-up in pediatric DTC.

MATERIALS AND METHODS

Patients under 19 years old diagnosed with DTC from 1980 to 2022 were retrospectively evaluated. sTg values and WBS were assessed after thyroidectomy and prior radioiodine treatment (RIT) and correlated with the possibility of finding distant metastasis and response to treatment at the end of follow-up.

RESULTS

In a total of 142 patients with a median age of 14.6 (4-18) years who were followed for 9.5 ± 7.2 years and classified according to the ATA risk of recurrence as low (28%), intermediate (16%), and high risk (56%), 127 patients had their sTg evaluated. A sTg value of 21.7 ng/dl yielded a sensitivity of 88% compared to 30% for DxWBS in predicting distant metastasis. Specificity was 60% and 100% respectively. 42% of patients obtained discordant results between DxWBS and RxWBS. In high-risk patients, sTg levels were particularly able to differentiate those who would have distant metastasis with better diagnostic accuracy than the WBSs.

CONCLUSIONS

The sTg level had better performance in detecting distant metastases in pediatric DTC than the DxWBS. DxWBS's low performance suggests that caution should be taken in interpreting their findings in terms of the underdiagnosis for metastatic disease, especially when the sTg level already suggests distant disease.

Differentiated Thyroid Cancers in Young Adults Versus Children: Clinical Characteristics and 10-year Follow-up Outcomes

BACKGROUND

Differentiated thyroid cancer (DTC) in young adults has been steadily rising in incidence over the decades. However, data on long-term outcomes in this specific cohort remain limited. In this study, we intended to evaluate young adults with DTC with regard to their clinical characteristics and treatment outcomes and compare the same vis-à-vis pediatric patients with DTC.

METHODS

Data of pediatric (≤18 years) and young adult (19-39 years) patients with DTC, from 1971 to 2016, were sequentially extracted and analyzed for clinical characteristics, treatment responses, rates of recurrent/persistent disease, and disease-free survival (DFS).

RESULTS

A total of 1803 patients with DTC were included (pediatric cohort: n = 176; young adult cohort: n = 1627). Pediatric patients with DTC had more frequent adverse baseline features including extrathyroidal extension (P = .040), nodal and distant metastases, and American Thyroid Association high-risk disease (P < .001 each). At 2 years posttreatment, young adult patients with DTC had significantly lower incomplete responses compared with pediatric patients with DTC (223/1627; 13.7% vs 94/176, 53.4%, respectively; P < .001). Over a median follow-up of 10.7 years, 120/1627 (7.4%) young adult patients with DTC had recurrent/persistent disease vs 23/176 (13.1%) pediatric patients with DTC (P = .012). The 10-year DFS probability was 93.6% for the young adult patients with DTC vs 88.7% for the pediatric patients with DTC (P = .007). American Thyroid Association high-risk disease and incomplete response at 2 years were independent predictors of significantly worse DFS in the young adult cohort (P < .001 each).

CONCLUSIONS

Young adult DTCs behave less aggressively compared with their pediatric counterparts with excellent long-term outcomes. Appropriate initial and dynamic risk stratification can help optimize treatment decisions and follow-up strategies.

Ultrasound, laboratory and histopathological insights in diagnosing papillary thyroid carcinoma in a paediatric population: a single centre follow-up study between 2000-2022

Background

Papillary thyroid carcinoma (PTC) often coincides with autoimmune thyroiditis (AIT); whether this association is incidental or causal remains debated.

Objective

To evaluate the ultrasonographic, laboratory, and histopathological features of PTC in paediatric patients with and without AIT and its relationship to puberty.

Design

A retrospective cohort study.

Patients and methods

A retrospective analysis of medical records of 90 patients (69; 76.7% females). The mean age at PTC diagnosis was 13.8 years [range 6-18]. All patients were evaluated ultrasonographically before thyroid surgery. Thyroid nodules were categorised using the European Thyroid Imaging Reporting and Data System (EU-TIRADS PL), and cytopathology was assessed using Bethesda criteria. Neck ultrasound results and thyroid and autoimmune status were correlated with histopathological PTC assessment.

Results

The coexistence of PTC and AIT was found in 48.9% (44/90) of patients. The percentage of AIT was increasing with age; AIT was present only in 1/3 of prepubertal, close to 50% in pubertal, and over 60% in adolescent patients. The youngest patients (aged <10 years old) presented more often with goitre and lymphadenopathy and less often with AIT than adolescents (15-18 years of age). There were no differences in TPOAb, TgAb, and TSH levels between the age subgroups. Presurgical TgAb levels were higher than those of TPOAb in the youngest patients. Histopathological analysis revealed that the solid subtype was observed more often in prepubertal children and diffuse sclerosing in children below 14 years of age, whereas the classic subtype dominated in late pubertal. Univariate and multivariate analyses revealed that lymph nodes metastases (LNM) were associated with PTC diameter and fT4 level, whereas extrathyroidal extension with age and angioinvasion with PTC diameter and age. The correlations between age and fibrosis, and the presence of psammoma bodies in malignant tissues were close to significant. We did not observe an association between TSH levels and the presence of autoimmunity and PTC variables.

Conclusions

In paediatric patients the natural course of PTC may be less aggressive in adolescent patients than in younger children (especially < 10 years of age). We suggest that pre-operative evaluation of paediatric patients with thyroid nodules could include apart from assessment of thyroid hormones, evaluation of TPOAb, TgAb, and TRAb together with comprehensive neck ultrasonography.

Ultrasound evolution of parenchymal changes in the thyroid gland with autoimmune thyroiditis in children prior to the development of papillary thyroid carcinoma - a follow-up study

Background

Follicular cell-derived thyroid carcinoma represents the vast majority of paediatric thyroid cancers (TCs). Papillary thyroid carcinoma (PTC) accounts for over 90% of all childhood TC cases, and its incidence in paediatric patients is increasing. The objective of this follow-up study was to present the outcome of ultrasound (US) and laboratory monitoring of paediatric patients with autoimmune thyroiditis (AIT) prior to the development of PTC.

Patients and methods

This prospective study included 180 children and adolescents (132 females; 73.3%) with a suspicion of thyroid disorder referred to the Outpatient Endocrine Department. The patients were divided into four groups: 1) 28 patients with a mean age of 10.7 [standard deviation (SD), 3.1] y, in whom PTC was detected during the active surveillance of AIT [AIT(+), PTC(+) follow up (F)]; 2) 18 patients with a mean age of 12.8 (SD, 3.4) y, in whom PTC and AIT were detected upon admission (A) [AIT(+), PTC(+) A]; 3) 45 patients with a mean age of 13.0 (SD, 3.4) y, in whom PTC was detected upon admission and AIT was excluded [AIT(-), PTC(+) A]; and 4) an age- and sex-matched control group of 89 patients with AIT and with a mean age of 9.4 (SD, 3.0) y. The analysis included clinical, US, and laboratory assessment results of children on admission (groups 1-4) and during follow-up (groups 1 and 4) in the Paediatric Endocrine Outpatient Department.

Results

Upon admission of those in group 1, the US evaluation revealed a hypoechogenic thyroid gland in 12 and an irregular normoechogenic gland in 16 patients. US monitoring revealed an increase in thyroid echogenicity and an increased irregularity of the thyroid structure during the follow-up period of all of the patients from group 1. Such changes were not noticed in group 4. PTC was diagnosed at the mean time of 3.6 y (3 mo-9 y) since AIT confirmation in group 1. The mean maximum PTC diameter as per the US was significantly smaller in group 1 than in groups 2 and 3 [13.2 (10.8) mm vs. 22.2 (12.8) and 22.05 (15.4) mm]. Fewer patients in group 1 were referred to 131I than in groups 2 and 3 (71.4% vs. 94.4 and 93.3%). Interestingly, significant differences were observed in the thyroglobulin antibody (TgAb)/thyroid peroxidase antibody (TPOAb) ratio between groups 2 and 3, as opposed to group 4, at the beginning of observation [15.3 (27.6) and 3.5 (8.8] vs. 0.77 (1.9)]. In group 1, after the follow-up, an increase in the TgAb/TPOAb ratio was observed [1.2 (9.8) to 5.2 (13.5)]. There were no significant differences between groups 1-3 in labeling index Ki67, lymph nodes metastasis, extrathyroidal extension, and angioinvasion. There were no associations between thyroid-stimulating hormone, TgAb, and the extent of the disease.

Conclusion

The use of thyroid US focused on the search for developing tumours in the routine follow-up of patients with AIT may not only help in the early detection of thyroid malignancies that are not clinically apparent but may also influence the invasiveness of oncological therapy and reduce the future side effects of 131I therapy. We propose that the repeat evaluation of TPOAb and TgAb warrants further exploration as a strategy to determine TC susceptibility in paediatric patients with AIT in larger multicentre studies.