Technetium-99m MIBI uptake in recurrent parathyroid carcinoma and brown tumors.

Demonstrable parathyroid adenoma in delayed (3-hr) 99mTc-MIBI neck imaging and localization of 201Tl-chloride in brown tumors mimicking skeletal metastases have been reported. Technetium-99m-MIBI scintigraphy is currently the imaging modality of choice for localizing parathyroid tumors in patients with recurrent hyperparathyroidism. This report is a good example of the use of 99mTc-MIBI in the diagnostic work-up of a patient with recurrent hyperparathyroidism, which turned out to be due to parathyroid carcinoma rather than the initial histopathologic diagnosis of parathyroid adenoma. Additionally, the patient's total body 99mTc-MIBI and 99mTc-MDP bone images showed multiple focal lesions in the bone-mimicking metastases.