Metastatic Papillary Thyroid Carcinoma in an Autonomous Hyperfunctioning Thyroid Nodule in an Adolescent: Case Report and Literature Review

Background: Although thyroid nodules are less common in children and adolescents, the malignancy rate for nodules is higher among children and adolescents than adults. A nodule that is discovered in a patient presenting with hyperthyroidism is usually a benign nodule or benign toxic adenoma and, thus, nodules are biopsied only infrequently. Objective: To report a case of papillary thyroid carcinoma presenting with a hyperfunctioning (hot) thyroid nodule. Case report: A 14-year-old female presented with symptoms of thyrotoxicosis and multi-nodular goitre. Laboratory findings were consistent with the diagnosis of thyrotoxicosis. Thyroid ultrasonography showed an enlarged thyroid gland with cystic and solitary nodules, diffuse heterogeneous echo, and microcalcifications. Doppler scans revealed increased vascularity within the left thyroid lobe and a solitary nodule. Thyroid scintigraphy revealed an autonomous nodule. Cytological examination of fine-needle aspirations from the solid nodule and left thyroid lobe revealed papillary thyroid carcinoma. The patient underwent total thyroidectomy. Histopathology of the thyroid gland and lymph nodes were also consistent with papillary thyroid carcinoma with nodal metastases. Conclusion: Contrary to the guidelines published by major endocrine societies, the detection of an autonomously functioning thyroid nodule in children and adolescents does not exclude the possibility of thyroid carcinoma. Suspicious hot nodules should be evaluated cytologically.