A rare case of a giant intrathyroidal parathyroid adenoma only localized with a 4D CT scan

Abstract

Ectopic parathyroid adenomas (PTAs) are quite rare and are typically located within the thymus, retroesophageal space, retropharyngeal space, or within the thyroid gland. Likewise, intrathyroidal parathyroid adenomas (IPAs) and giant PTAs are also a rare subset of PTAs. To date, only six studies have investigated localizing techniques of IPAs using 4-dimensional computed tomography (4D CT) scan with only one study demonstrating two IPAs successfully localized using both 4D CT scan and 4-dimensional magnetic resonance imaging. We describe a single lesion in a patient which would be classified both as an IPA and a giant parathyroid adenoma (GPA). This lesion only successfully localised with a 4D CT scan which is not in keeping and unusual with the available literature.

Keywords: Intrathyroidal parathyroid adenoma, 4-Dimensional computed tomography scan, Technetium based scintigraphy