Rare Imaging Findings of Concomitant Presence of Multiple Parathyroid Adenomas and Carcinoma in a Chronic Kidney Disease Patient with Tertiary Hyperparathyroidism Detected on 99mTc-Sestamibi Single-Photon-Emission Computed Tomography/Computed Tomography Scintigraphy.

Parathyroid carcinoma (PC) is a rare endocrine carcinoma. It is one of the rare causes for primary hyperparathyroidism. It is very uncommon in individuals with secondary or tertiary hyperparathyroidism. We report a rare case of 53-year-old male, a known case of chronic kidney disease on dialysis, who presented with fatigue and muscle cramps. Lab reports revealed elevated parathyroid hormone (PTH) and serum calcium levels. 99mTc-Sestamibi single-photon-emission computed tomography/computed tomography scintigraphy showed 4 foci of increased tracer uptake with retention, suggestive of parathyroid adenomas, including two ectopic foci in the mediastinum. At surgery, the enlarged bilateral superior, left inferior parathyroid gland, and two calcified left superior mediastinal lesions were removed. Histopathology revealed parathyroid adenomas in the right superior, left inferior, supernumerary ectopic left superior mediastinum lesion and PC in the left superior parathyroid lesion. Intraoperative serum PTH became normal, and the patient is asymptomatic now.