An Unusual “Thyroid Cyst”: Intrathyroidal Parathyroid Cyst

Excerpt

Pathology involving the parathyroid glands most often ranges from benign (adenoma and hyperplasia) to the very rare, parathyroid carcinoma. Other pathologic conditions are decidedly uncommon. Parathyroid glands are a very common source of intra-operative frozen sections: for the surgeon, the challenge lies in identifying, locating and dissecting the parathyroid glands; for the pathologist, the challenge is to be aware of ectopic locations and unusual pathology associated with the parathyroids in these locations. The case under presentation is unusual not only because of the intrathyroidal location of a parathyroid gland but also because the ectopic parathyroid gland developed a cyst which clinically presented as an intrinsic “thyroid” swelling. While an intrathyroidal location of a parathyroid gland is rare, it is nonetheless, well described, pathologic conditions affecting such ectopically sited glands are rare. …