Abstract
Background : Lipoadenoma of the thyroid gland is a rare variant of follicular adenoma and consists of a mixture of mature adipose cells and follicles. We report two cases of lipoadenoma of the thyroid gland, with special emphasis on the cytologic findings.
Case 1 : A 69-year-old woman noticed swelling of the right side of her neck and consulted our hospital. Malignancy was suspected based on the fine-needle aspiration (FNA) cytology findings, and hemithyroidectomy and lymph node dissection were performed.
Case 2 : A 52-year-old woman experienced discomfort in her neck and consulted our hospital. FNA yielded benign follicular cells, but malignancy was suspected based on the ultrasonography findings, and hemithyroidectomy was performed.
Histopathologically, both tumors were lipoadenomas. A retrospective review of the FNA specimens led to the detection of small foci of fat cells intermingled with follicular cells.
Conclusion : We think that it is possible to diagnose of lipoadenoma based on the FNA findings when clusters of follicular cells containing fat cells are observed.
