RESUMEN
Primary thyroid paraganglioma (TP) is an uncommon tumor, and in rare cases, this disease tends to mimic medullary thyroid carcinoma (MTC). The present study reports a rare case of primary TP mimicking thyroid carcinoma, accompanied by hyperthyroidism. A 30-year-old female presented with an anterior cervical mass. Pre-operative radiological studies and operative frozen section analysis indicated an atypical MTC. Primary TP was finally diagnosed by pathology and immunohistochemical staining. Laboratory examinations (thyroid hormones tests) and Tc99m emission computed tomography revealed hyperthyroidism. Gene analysis of TP-associated gene mutations was negative. Surgical resection was performed as a curative approach and there is currently no metastasis after 36 months of follow-up. Surgeons must be aware of this disease in order to ensure a correct diagnosis and to prevent them from performing unnecessary procedures. The current study presents a case of primary TP mimicking MTC, discusses the radiographic results and histological characteristics, and provides a review of the associated literature.