Pediatric Thyroid Carcinoma in Patients with Graves' Disease: The Role of Ultrasound in Selecting Patients for Definitive Therapy

Abstract

Background/Aims: Pediatric Graves' disease (GD) accounts for 10-15% of all thyroid disorders in patients ≤18 years and is treated with antithyroid medication or definitive therapy [radioactive iodine (RAI) ablation vs. surgery]. Patients with GD may have concurrent differentiated thyroid cancer (DTC). DTC prevalence in pediatric GD is not well established. We examined the prevalence of DTC in pediatric GD and the role of preoperative thyroid ultrasound (US) in selecting the appropriate definitive therapy. Methods: This is a single-institution, retrospective, cross-sectional study of 32 GD patients with a median age of 11 years (range 3-18) who underwent total thyroidectomy as the definitive treatment between 2005 and 2014. Results: DTC was identified in 22% of the GD patients. A total of 97% completed preoperative thyroid US, and thyroid nodules were identified in 13/32 patients (41%). Preoperative fine needle aspiration (FNA) biopsy was performed in 6/13 patients, accounting for four preoperative diagnoses of concurrent DTC. Extra-thyroidal extension was present in 4/7 (63%), regional lymph node metastasis in 3/7 (43%), and lung metastasis in 2/7 patients (29%). Conclusions: Concurrent DTC occurs in pediatric GD patients. Thyroid US is an efficient tool for selecting patients for thyroidectomy. For patients with a nodule on US before definitive therapy, FNA should be performed to appropriately select thyroidectomy versus RAI ablation.