Long-term impact of initial surgical and medical therapy on young patients with papillary thyroid cancer and bilateral cervical metastases:

Aspects of economic costs and evaluation of health surveillance systems after a radiation accident with a focus on an ultrasound thyroid screening programme for children

Health surveillance initiatives targeted at populations evacuated from, and residing in, areas affected by radiation contamination were implemented by international institutions as well as national and local governments after the nuclear accidents of Chernobyl and Fukushima Dai-ichi nuclear power plants. Most of these initiatives included a component of childhood thyroid cancer monitoring, with the more comprehensive schemes corresponding to national programmes of health monitoring for adults and children around general health and wellbeing. This article provides a short overview of available data on the costs and resources associated with surveillance responses to two recent nuclear accidents: Chernobyl and the Fukushima Dai-Ichi nuclear plant accidents. Moreover, because the balance of costs and benefits of health surveillance after a nuclear accident can influence decisions on implementation, we also present a brief overview of the principles of economic evaluation for collecting and presenting data on costs and outcomes of a surveillance programme after a nuclear accident. We apply these principles in a balance sheet analysis of a post-accident ultrasound thyroid screening programme for children.

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).

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

BACKGROUND

Treatment approaches for pediatric papillary thyroid cancer (PTC) are historically extrapolated from adult experience. However, pediatric PTC demonstrates a greater propensity for lymph node involvement, early metastases, and recurrence, highlighting the need for pediatric-specific treatment paradigms.

MATERIALS AND METHODS

A retrospective review included patients with PTC aged ≤21 y, with ≥18 mo of follow-up, treated between 2002 and 2015. Fisher's exact test and Cox proportional hazard were used to estimate the effect of risk factors on disease recurrence.

RESULTS

Seventy-two cases of PTC were identified with median age of 17.0 y and median follow-up of 64.1 mo. Disease recurred at a median of 24.6 mo (range 7.8-78.1) in 7 of 51 (13.7%) of patients with disease limited to the thyroid or central neck, 7 of 18 (39%) patients with lateral neck disease at presentation who underwent a compartment-based resection, and three of three patients (100%) with lateral neck disease who sought care after non-compartment-based resection. There were no deaths from disease. Univariate predictors of recurrence included tumor size >2 cm (P = 0.005), lateral neck disease (P = 0.004), lymphovascular invasion (P = 0.017), extracapsular invasion (P < 0.0001), multifocality (P = 0.03), and non-Caucasian race (P = 0.05). Multivariate analysis identified race (P = 0.05) as an independent predictor of recurrence. In patients without lateral neck disease, there was a trend toward lower recurrence in patients undergoing thyroidectomy with central neck dissection compared with thyroidectomy alone (P = 0.07).

CONCLUSIONS

Pediatric PTC is associated with excellent survival, although recurrence is common in patients with lateral node involvement. Predictors of recurrence are multifactorial and may be influenced by extent of disease, patient or tumor biology, and aggressiveness of resection.

LEVEL OF EVIDENCE

Prognosis study, level IV, retrospective case series.

Prognostic Factors for Differentiated Thyroid Carcinoma and Review of the Literature

Objective

Prognostic factors of differentiated thyroid carcinoma (DTC) are analyzed to justify the diagnostic and therapeutic modalities of DTC in current practice.

Methods

Patients undergoing curative resection for histologically diagnosed DTC (n = 150) were consecutively enrolled, and the clinical and pathological data were retrospectively reviewed.

Results

The DTC patient cohort consisted of 113 females (75.3%; mean age at the time of onset, 40.1 ± 12.0 yr) and 37 males (24.7%; 47.5 ± 16.2 yr). The pathological types of DTC included papillary thyroid carcinoma (n = 131, 87.3%) and follicular thyroid carcinoma (n = 19, 12.7%). The follow-up period ranged from 4.2 to 31 years, in which period 140 (93.3%) patients survived, 30 (20.0%) patients relapsed, and 10 (6.7%) patients died of DTC. Surgical procedures used for the curative resection consisted of near-total or subtotal thyroidectomy (n = 83, 55.3%), partial thyroidectomy (n = 64, 42.7%) and total thyroidectomy (n = 3, 2.0%). Out of those patients undergoing concomitant lymph node dissection (n = 63, 42.0%), 45 patients (71.4%) had detectable lymph node metastases. Postoperatively, 12 patients (8.0%) received external beam radiotherapy, 16 patients (10.7%) received chemotherapy, 37 patients (24.7%) received 131I therapy, and 66 patients (44.0%) received additional long-term L-T4 or thyroid hormone treatment. Age of onset, tumor size at initial visit, and rate of early metastasis showed statistically significant differences between the mortality group and the survival group (P <0.05) and between the recurrence group and the recurrence-free group (P <0.05).

Conclusions

Age, tumor size at initial visit, and early metastasis are prognostic factors for DTC, requiring a stratified management in clinical practice.

Using Ion Torrent sequencing to study genetic mutation profiles of fatal thyroid cancers

BACKGROUND/PURPOSE

Surgery followed by radioiodine is a mainstay of treatment for thyroid cancers of follicular origins. However, about 5% of the thyroid cancers are non-operable and/or radioiodine-refractory diseases, which are either locally advanced or metastatic and result in a survival of less than 5 years. How to treat this population of thyroid cancer patients becomes a critical issue requiring further understanding of the tumor's genetic information.

METHODS

We used formalin-fixed paraffin-embedded specimens of 22 fatal thyroid cancers and their corresponding non-tumor parts, if available, to yield genomic DNA, and applied the Ion Torrent™ Personal Genome Machine (IT-PGM) System (Life Technologies), a next generation sequencing technology, to interrogate 740 mutational hotspots in 46 oncogenes. We further validated the results by conventional direct sequencing.

RESULTS

We confirmed 21 mutations of 11 oncogenes in the 22 fatal thyroid cancer samples. Among them, the MET p.N375S and MLH1 p.V384D mutations, each was detected in two cases, and has rarely been found to be involved in thyroid cancer pathogenesis before. We also identified homozygous PDGFRA p.V824V mutation in eight out of the 22 cases, while the non-tumor counterparts carried heterozygous PDGFRA p.V824V mutation. We noted that the Ion Torrent technique unfortunately showed high false positive rates for detecting EGFR mutations in thyroid cancers.

CONCLUSION

The extensive genetic studies provide new insights to future targeted therapy in these patients. IT-PGM proved to be valuable for comprehensively searching genetic mutations in potentially fatal thyroid cancers.

Conservative or radical surgery for pediatric papillary thyroid carcinoma: A systematic review of the literature

BACKGROUND

Pediatric papillary thyroid carcinoma (PTC) is characterized by an aggressive clinical course. Early diagnosis is a challenge and treatment consists principally of partial or total thyroidectomy±neck dissection and radioactive iodine therapy. Due to the rarity of PTC in children, there is no consensus on optimal surgical treatment.

METHODS AND RESULTS

A literature search was carried out using PubMed, Embase, Medline, Cochrane and Web of Science. Seven studies (489 patients) investigating the outcome of surgically managed pediatric PTC were identified. No clear advantage in survival or recurrence rate was found for total thyroidectomy compared to other surgical approaches.

CONCLUSION

Despite the aggressive behavior of PTC, prognosis is good, with low mortality. After removal of disease and prevention of recurrence, reduction of iatrogenic complications are a priority in this age group. Due to the paucity of available evidence, this review cannot recommend conservative or radical surgery for pediatric papillary thyroid carcinoma. To answer this question, we recommend the establishment of a randomized controlled trial with adequately matched baseline variables.

Factors predictive of papillary thyroid micro-carcinoma with bilateral involvement and central lymph node metastasis: a retrospective study

Background

The optimal resection extent for papillary thyroid microcarcinoma (PTMC) remains controversial. The objective of the study was to investigate risk factors of bilateral PTMC and central lymph node metastasis (CLNM) to guide surgical strategies for PTMC patients.

Methods

We retrospectively reviewed 211 PTMC patients who underwent total thyroidectomy (TT) and 122 clinical lymph node-negative (cN0) cases that underwent prophylactic central lymph node dissection (CLND) between 2010 and 2011. The frequency, pattern, and predictive factors for bilateral PTMC and CLNM in these patients were studied using univariate and multivariate analysis with respect to the following variables: age, gender, extrathyroidal extension (ETE), T stage, with Hashimoto thyroiditis (HT), tumor size and multifocality based on final pathology, and preoperative evaluation using ultrasonography (US).

Results

Fifty-four of 211 (25.6%) patients had bilateral PTMC. In multivariate analysis, multifocality (P < 0.001, OR = 23.900) and tumor size ≥7 mm (P = 0.014, OR = 2.398) based on US were independent predictive factors for bilateral PTMC which was also independently associated with multifocality (P < 0.001, OR = 29.657) and tumor size ≥7 mm (P = 0.005, OR = 2.863) based on final pathology. Among 122 cN0 patients who underwent prophylactic CLND, we found 49.2% of patients had CLNM. CLNM was independently associated with men, age <50 years and tumor size ≥7 mm based on final pathology or preoperative US.

Conclusions

TT should be considered for PTMC patients who are found multifocality and tumor size ≥7 mm based on preoperative US. CLND need be considered in cN0 patients who are men, aged <50 years or tumor size ≥7 mm based on preoperative US.

Thyroid surgery at Children's Hospital Boston: a 35-year single-institution experience

BACKGROUND/PURPOSE

Thyroidectomy is the primary therapy for thyroid cancer and an established treatment of hyperthyroidism. Because of the relative rarity of these conditions in childhood, few single-institution series exist in the pediatric literature. Here we analyze our institution's experience to assess patient demographics, operative risks, and the role of preoperative testing.

METHODS

This is a retrospective chart review of 175 consecutive patients not older than 18 years who underwent thyroid surgery at Children's Hospital Boston from 1970 to 2004.

RESULTS

The most common indication for thyroidectomy was thyroid nodules (83%), followed by hyperthyroidism (7%) and goiter (7%). For children referred for nodules, we observed a peak incidence in adolescence and a female to male ratio of 3.7:1. Cancer was found in 36%, with papillary thyroid cancer the most common subtype (85%). Operative complications were rare, with permanent hypocalcemia in 2 (4.7%) of 43 patients who underwent bilateral resection for thyroid nodules (no cases of permanent hypocalcemia in other procedures). Permanent unilateral vocal cord paralysis was documented in 2 children after the resection of malignant nodules.

CONCLUSIONS

Pediatric thyroidectomy can be performed with low operative risk. Because permanent hypocalcemia remains an obligate risk of bilateral thyroidectomy, we recommend the routine use of preoperative fine-needle aspiration to guide the extent of initial surgical resection, reserving near-total thyroidectomy for those cases where cytology is positive for malignancy.

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.