Ectopic thyroid tissue in the adrenal gland: a case report with clinical and pathogenetic implications.

Ectopic thyroid tissue (ETT) was usually discovered in head and neck region, adrenal ETT was rare reported in literature. Here is a report of adrenal gland cyst with ETT in a 49-year old woman who was admitted to our hospital for health care. CT scan demonstrated a mass in left adrenal gland, and surgical resection was prepared. The mass was cystic, composed of normal adrenal and ectopic thyroid tissue, and was histologically benign. Immnunohistochemistry showed that the ETT was positive for TG and TTF-1, molecular examination indicated that ETT was without the molecular alterations associated with thyroid carcinoma (BRAF V600E, K-RAS). Further work-up did not show evidence of thyroid malignancy.