THYROID NODULES/CANCER IN CHILDREN-HOW FREQUENT IS THE PROBLEM? Thyroid nodules are less common among children than adults but are more likely to be malignant in children referred for evaluation of nodular thyroid disease (25 % vs. 5 %). Estimates from ultrasound (US) and postmortem examination suggest that 1 % - 1.5 % of children and up to 15 % of older adolescents or young adults have thyroid nodules, although it remains unclear how many of these would have become clinically apparent. In general, the prevalence of thyroid nodules is much greater in children than is generally appreciated. It remains unclear how many of these nodules would reach a clinical threshold during childhood. Risk factors for developing thyroid nodules in children include head and neck irradiation, female gender, iodine deficiency, age of puberty, and family or personal history of thyroid disease. Several nonthyroid diseases, such as abscesses, lymphatic or vascular malformations, ectopic thymus, thyroglos...