This paper aims to present one of the rarest types of malignancies, parathyroid carcinoma. Parathyroid carcinoma is an important cause of primary hyper par athyroidism. Diagnostic evaluation of patients presenting with signs and symptoms of hyperparathyroidism consists of serum calcium and parathyroid hormone determination, parathyroid imaging using ultrasound, computed tomography, magnetic resonance imaging, or Tc-99m sestamibi scintigraphy, and histopathologic evaluation of tissues after surgical intervention. Therapeutic management of an identified parathyroid tumor is by parathyroidectomy during neck exploration or radioisotope-guided with the use of a gamma probe. The histology of a resected tumor determines if the initial surgery completes the management, or, in cases of parathyroid carcinoma, if another completion surgical intervention is to be made. This paper will present a patient who has been initially diagnosed with primary hyperparathyroidism and was referred to our nuclear medicine department for parathyroid scintigraphy. The patient underwent MIRP and rapid intraoperative PTH determination. Histopathologic report on the tissues revealed parathyroid carcinoma. The patient underwent a second surgery for definitive treatment. This paper will discuss the clinical role of nuclear medicine in the diagnosis and surgical management of parathyroid carcinoma.