Cytologic Features and BRAF Mutation of Hyalinizing Trabecular Adenoma of the Thyroid: A Case Report with Review of the Literature

ABSTRACT

A hyalinizing trabecular adenoma (HTA) is a rare benign thyroid tumor of follicular epithelial cell origin with a trabecular-alveolar growth pattern and marked intratrabecular hyalinization. The cytological and histological features of HTA are very similar to those of papillary and medullary carcinomas of the thyroid. Therefore, an accurate diagnosis of HTA is important to avoid unnecessary and potentially harmful management of patients. However, the results of BRAF gene mutation analysis shown by many studies are distinctly different between HTAs and papillary thyroid carcinomas. Herein, we describe a rare case of HTA of the thyroid in a 49-year-old female and consider its characteristic cytological features and BRAF gene mutation analysis results with a brief review of the literature.