Atypical non-[99mTc]Tc-MIBI avid parathyroid adenoma with a sternal brown tumor, mimicking ectopic parathyroid adenoma in planar and SPECT images: Importance of SPECT/CT acquisition

Document Type : Case Report


1 Nuclear Medicine Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

2 Metabolic Syndrome Research Center, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

3 Cardiothoracic Surgery and Transplant Research Center, Imam Reza Hospital, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran


Primary hyperparathyroidism (pHPT) is defined by the excess level of parathyroid hormone (PTH). Parathyroid adenoma is responsible for about 80% of all pHPT. Parathyroid adenoma with cystic feature and atypical pathology is recognized as a rare entity. Technetium-99m methoxy isobutyl isonitrile ([99mTc]Tc-MIBI) scintigraphy has favorable detection rate for ectopic gland as well as the brown tumors. SPECT/CT plays critical role in localizing abnormal tracer uptake. Herein, we report a severely hypercalcemic patient with cystic atypical parathyroid adenoma and mediastinal uptake, which was confined to a sternal lytic lesion (suggestive of brown tumor), which highlights the importance of SPECT/CT in [99mTc]Tc-MIBI imaging.


Main Subjects

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