Inferior laryngeal paraganglioma mimicking a primary thyroid tumor.

Objective: To report an unusual case of inferior laryngeal paraganglioma that manifested as a thyroid neoplasm.

Methods: A case report is presented, including ultra-sonographic, surgical, histologic, and immunohistochemical findings, and diagnostic and therapeutic strategies are discussed.

Results: In a 33-year-old man with a mass in the left side of his neck, color Doppler ultrasonography revealed an extremely hypervascular lesion that appeared to arise in the left lobe of the thyroid gland. Fine-needle aspiration was noncontributory because of bloody samples, but core biopsy specimens suggested a nonthyroidal neoplasm. At surgical intervention, a 3.5-cm mass was found immediately posterior to the left thyroid lobe, not involving the thyroid capsule. Because the mass could not be dissected free from the thyroid, performance of a left thyroid lobectomy and isthmectomy was necessary. The pathology specimen was a paraganglioma.

Conclusion: Paragangliomas may be sonographically similar to thyroid neoplasms and may be included in the differential diagnosis of a hypervascular thyroid mass.