A standardized assessment of thyroid nodules in children confirms higher cancer prevalence than in adults

Abstract

Context: Thyroid cancer is the most common endocrine malignancy, but due to its rare occurrence in the pediatric population, the cancer risk of childhood thyroid nodules is incompletely defined, and optimal management of children with suspected nodules is debated.

Objective: The aim was to study the presenting features and cancer risk of sporadic childhood thyroid nodules using a standardized clinical assessment and management plan.

Design and setting: Boston Children's Hospital and Brigham and Women's Hospital collaborated to create a multidisciplinary pediatric thyroid nodule clinic and implement a standardized assessment plan. Upon referral for a suspected nodule, serum TSH was measured and hypothyrotropinemic patients underwent (123)I scintigraphy. All others underwent thyroid ultrasonography, and if this confirmed nodule(s) ≥ 1 cm, ultrasound-guided fine-needle aspiration was performed. Medical records were retrospectively reviewed and compared to a control population of 2582 adults evaluated by identical methods.

Patients and results: Of 300 consecutive children referred for the initial evaluation of suspected thyroid nodules from 1997 to 2011, 17 were diagnosed with autonomous nodules by scintigraphy. Neck ultrasonography performed in the remainder revealed that biopsy was unnecessary in over half, either by documenting only sub-centimeter nodules or showing that no nodule was present. A total of 125 children met criteria for thyroid biopsy, which was performed without complication. Their rate of cancer was 22%, significantly higher than the adult rate of 14% (P = .02).

Conclusions: Neck ultrasonography and biopsy were key to the evaluation of children with suspected thyroid nodules. Although the relative cancer prevalence of sonographically confirmed nodules ≥ 1 cm is higher in pediatric patients than adults, most children referred for suspected nodules have benign conditions, and efforts to avoid unnecessary surgery in this majority are warranted.

Figure 1.

Standard diagnostic algorithm. UG-FNA, ultrasound-guided fine-needle aspiration.

Figure 2.

Study population (A) and representative ultrasonography (B–G). A, Patients were stratified by serum TSH and imaging. *, Tumors of nonthyroid origin included 2 thyroglossal duct cysts, 1 Burkitt lymphoma, 1 high-grade peripheral nerve sheath tumor, 1 undifferentiated sarcoma, 1 benign parathyroid cyst, 1 renal clear cell sarcoma metastasis, 1 ganglioneuroma, and 1 ectopic thymic rest. Three patient ultrasound studies are shown. B and C, Transverse (B) and sagittal (C) images of Hashimoto's thyroiditis, characterized by diffuse heterogeneity of the entire gland and a thickened isthmus (calipers; 1.04 cm) without a discrete nodule. D and E, Transverse (D) and sagittal (E) images of the diffuse sclerosing variant of papillary thyroid cancer, characterized by innumerable punctate echogenicities without a focal lesion. F and G, Transverse (F) and sagittal (G) images of a well-defined, complex (<25% cystic) nodule (calipers) with surrounding normal thyroid. T, trachea.

Figure 3.

Age and gender distribution of benign and cancerous nodules.