Myxoid lipoadenoma of the parathyroid gland.

A myxoid lipoadenoma of the parathyroid gland causing primary hyperparathyroidism is reported. The very rare and histologically unusual tumor consists of an epithelial component which is combined with a stromal component in a characteristic way. Slender, irregularly branched trabeculae which mainly consist of chief cells as well as a few oxyphil cells are found as epithelial component. The predominantly myxomatous and only focally lipomatous stromal component is interpreted as an integrated tumor component of the lipoadenoma which is derived from the parathyroid adipose tissue.