Background: The association of hyperparathyroidism due to parathyroid adenoma with differentiated thyroid cancer is not often considered because of its low incidence, and the presence of a parathyroid adenoma in an intrathyroidal position is rare. We report a case in which both conditions coexisted.
Case Report: The case is of a 53-years-old female patient who was diagnosed to have primary hyperparathyroidism due to a parathyroid adenoma in the right lower parathyroid gland as confirmed by biochemical and radiological investigations. During surgery the adenoma was found to be intrathyroidal in the lower part of the right thyroid lobe. Right lobectomy and isthemectomy were performed. Histology of the removed thyroid revealed the presence of an associated incidental papillary thyroid carcinoma in addition to the intrathyroidal parathyroid adenoma. The case is substantiated with published case reviews.
Conclusion: This case illustrates the need for clinical awareness of concomitant hyperparathyroidism and nonmedullary thyroid carcinoma and the possible presence of a parathyroid adenoma in an intrathyroidal position.

Keywords: Hyperparathyroidism, Incidental, papillary thyroid carcinoma, parathyroid adenoma, Intrathyroidal