Ectopic parathyroid adenoma--the hidden culprit.

Primary Hyperparathyroidism is known to present with protean manifestations leading to misdiagnosis in the initial stages of the disease. Inability to locate the adenoma in an ectopic parathyroid gland may further delay the diagnosis of these cases. Aberrant migration during development may lead to intrathyroidal or other ectopic locations of parathyroid glands. This may lead to their misdiagnosis as a thyroid nodule or failure to locate parathyroids during surgery. Similarity in cytological picture between thyroids and parathyroids may further complicate diagnosis by fine needle aspiration cytology. Nuclear imaging scintigraphy accurately localizes the tumor in 90% of cases and simplifies the surgical management. We encountered three such cases with the parathyroid gland adenomas in ectopic locations in which pre-operative nuclear imaging played a major role.