Cancer in thyroid nodules with fine-needle aspiration in Korean pediatric populations

Clinical, sonographical, and pathological findings of pediatric thyroid nodules

Thyroid nodules are less frequent in children than in adults. A higher rate of malignancy is highlighted in this group. We aimed to analyze the clinical, laboratory, and ultrasound (US) findings of children and adolescents with benign and malignant thyroid nodules. This was a retrospective review of children and adolescents evaluated at a tertiary pediatric institution between 2007 and 2019. Patients with autonomously functioning nodules, autoimmune thyroid diseases, and a history of oncohematological disorders were excluded. A total of 102 patients with 131 nodules were identified. The study population included 57 females (55.9%); the average age was 10.6 ±4 years. Thirty-five nodules (26.7%) ranging 4.5-36 mm had a fine-needle aspiration (FNA) done: 45.7% (n = 16) were benign, 11.4% (n = 4) were classified as atypia, and 8.5% (n = 3) were consistent with papillary carcinoma. Fourteen patients (13.7%) underwent surgery. Five (4.9%) were finally diagnosed with papillary thyroid cancer. Of the 6 patients with benign FNAs, all except one, which was initially reported as atypia by an earlier FNA but was later diagnosed with papillary carcinoma, had a colloid nodular goiter. Of the 3 patients with atypia FNAs, one was found to be papillary carcinoma. One hundred twenty-five benign nodules (21 based on cytology and/or histology, 104 on clinical and imaging follow-up) were diagnosed. Nodule size, microcalcifications, solid parenchyma, and pathologic lymph node alterations were associated with malignancy, but nodule growth was not.Conclusion: Diagnostic approach and management of children with thyroid nodules should be based on a stepwise evaluation including clinical, laboratory, and US findings. Of the 102 patients identified, 4.9% had thyroid carcinoma below the range described in previous literature. What is Known: • Thyroid nodules are less frequent in children than in adults but more frequently malignant. Research on factors associated with malignancy have mostly been conducted in adults; further studies in pediatric thyroid nodules are warranted. What is New: • Microcalcifications, pathologic lymph node alterations, solid parenchyma, and larger nodule size are associated with malignant nodules, but nodule growth is not always suggestive of thyroid malignancy. The incidence of thyroid malignancy in this population was below the reported worldwide incidence in children with thyroid nodules.