Case Report

Pediatric Medullary Carcinoma of the Thyroid with Point Mutation of RET Proto-oncogene Associated with Multiple Endocrine Neoplasia and Initially Diagnosed by Fine-Needle Aspiration Biopsy

A 7-year-old girl presented with a thyroid mass, elevated serum levels of calcitonin and carcinoembryonic antigen, as well as multiple mucosal nodules in the upper lip and tongue. Cytologic material obtained by fine-needle aspiration biopsy from the thyroid mass was diagnosed as medullary carcinoma and confirmed by immunohistochemical studies in…