Patterns and Predictors of Metastatic Spread to the Neck in Pediatric Thyroid Carcinoma

Abstract

Objective Evaluate patterns and predictors of spread to the neck in pediatric metastatic differentiated thyroid carcinoma (DTC). Methods Patients <18 years old undergoing thyroidectomy by a single surgeon from January 2015 to December 2019 were included. Neck sublevels were removed separately according to AJCC boundaries. Clinical outcomes included nerve injury, hypocalcemia, hematoma, and residual tumor. Results Forty‐eight children underwent thyroid surgery. Thirty (63%) were for malignancy, 27 (90%) of which were DTC. Nineteen (70%) patients with DTC underwent 24 neck dissections; 19 central plus lateral and 5 central alone. The female to male ratio increased from 1:1 to 3:1 with age. Two children with lateral neck involvement had sub‐centimeter primaries. Patients requiring neck dissection were more likely to have 1) diffuse sclerosing or tall cell variant, 2) T3 or T4 disease, 3) genetic mutation, 4) lymphatic invasion, 5) extracapsular extension, 6) positive resection margin. Levels IIA (79%), III (89%), IV (84%), VI (100%) were most commonly involved. Levels IB (16%), IIB (16%), VB (16%) were also involved, often without involvement of adjacent levels. Permanent injuries included one unilateral recurrent laryngeal nerve, one mild marginal mandibular nerve and one mild accessory nerve. Hypocalcemia was highest following neck dissection for malignant disease. One patient was re‐operated for a mediastinal node. Most patients with N1 disease received radioactive iodine. Most patients have no evidence or indeterminate disease on long‐term follow‐up. Conclusion Children with lateral nodal spread from DTC should be considered for neck dissection including Levels IB, IIA, IIB, III, IV, VB, bilateral VI. Level of Evidence 4 Laryngoscope, 131:E1002–E1009, 2021

2022 European Thyroid Association Guidelines for the management of pediatric thyroid nodules and differentiated thyroid carcinoma

“…However, often, the predictors of nodal neck disease of DTC such as tumor size of T3/T4, tumor multifocality, thyroid capsule infiltration, diffuse sclerosing variant, lymphatic and vascular invasion can only be assessed post-operatively ( 87 , 92 ). Frozen section histopathology may help to identify all or some of these features.…”

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

“…Additional negative prognostic factors include younger age, male gender, tumour size, mixed hystotype, bilateral localization, unilobar multifocality, extrathyroidal extension, incomplete surgical resection of the tumour and high post-ablation stimulated thyroglobulin levels (27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41).…”

“…Persistent disease occurs more frequently with higher T stage and when lymph node or distant metastases are present or when high stimulated thyroglobulin is observed after surgery (33)(34). A high lymph node ratio (LNR, ratio of the number of positive to the total number of lymph nodes removed) after initial therapy is considered an independent determinant predictive of persistent disease (35).…”

Molecular features of thyroid cancer in children

“…В то время как у 68% пациентов, которым потребовалась шейная диссекция, были соматические мутации, только у 38% пациентов без метастазов в лимфатических узлах были обнаружены молекулярные изменения. Опираясь на это, авторы предположили, что статус генетической мутации является предиктором метастазов в лимфоузлы, и такие пациенты должны находиться под тщательным наблюдением, если первоначально не требовалось проведения шейной диссекции [86].…”