Insular carcinoma of the thyroid in a 10-year-old child

Thyroid carcinomas are relatively infrequent in the pediatric age group, the majority of which are papillary carcinomas. Poorly differentiated carcinomas are very rare in this age group. Insular carcinoma is a unique subset of poorly differentiated carcinoma of thyroid, which occurs predominantly in adults older than 50 years. In terms of prognosis, insular carcinoma of thyroid occupies a place in between that of well-differentiated papillary/follicular carcinoma and anaplastic carcinoma. The authors describe a case of insular carcinoma of thyroid in a 10-year-old girl who underwent hemithyroidectomy based on a preoperative diagnosis (by fine-needle aspiration cytology) of colloid goiter, and after histopathologic diagnosis of the specimen, a completion thyroidectomy was performed with block dissection of the neck. The authors believe this to be the youngest case of insular carcinoma of thyroid to be reported.