Endocrine Abstracts

Ectopic mediastinal parathyroid adenoma is a rare cause of primary hyperparathyroidism (PHPT), which is reported in 1-1.5% of patients. We present you a case of a 22-year old male, who was suffering from severe itchiness which significantly interferes with his daily activities of life. His laboratory results were suggestive of PHPT (Table 1). His initial scans, including Technetium-99m (Tc-99m) Sestamibi (Mibi) did not reveal any abnormality. Subsequently, increase of PTH level along with new onset nausea and fatigue were observed, due to which further investigation was required. His neck and head Ultrasonography (USG) was normal. Second Tc-99m Mibi illustrated an anterior mediastinal mass in the thymic area with focal atypic activity, which is suggestive of a potential ectopic parathyroid adenoma. To accurately localize the adenoma, choline Positron Emission Tomography-Magnetic Resonance Imaginging (PET-MRI) and choline PET-Computer Tomography (CT) were ordered. The images of PET-CT were correlating with the data obtained from the parathyroid scintigraphy. It is recommended to perform parathyroidectomy to PHPT patients, who are diagnosed at 50 years or younger regardless of existence of other surgery indications. Consequently, the patient underwent parathyroidectomy and left thymectomy. Histopathological examination has confirmed the diagnosis. His follow-up blood results were within normal limits and symptoms were resolved (Table 1). The most challenging aspect of the management of PHPT is establishing the accurate localization of the hyperfunctioning adenoma. In addition to that, localization has a huge impact on the success of parathyroidectomy. Although there are many techniques such as USG, Tc99m-Mibi, parathyroid four-dimension CT, PET and MRI, no universally recommended algorithm exists. The most commonly used method is concordant application of USG and Tc99m-Mibi. The reported case had been succesfully treated following useage of Tc99m-Mibi and choline PET-CT to establish the accurate location of the adenoma. We strongly believe that our approach with a multimodality imaging strategy provides valuable information to the physicians.