| pubmed-article:15138715 | pubmed:abstractText | The accessory midline thyroids are ascribed to an arrest of migration of the median thyroid anlage, while the lateral ectopic thyroids have induced a hypothesis of the presence of lateral thyroid anlage. We report the case of a 67-year-old man who presented with dyspnea and dysphagia of 1 year's duration. The clinical examination and radiological investigations (CT and MRI) showed a solid heterogeneous mass in the right parapharyngeal space. The fine needle aspiration biopsy was inconsistent. The mass (3x2.5x3.5 cm) was excised via a transoral approach. It was capsulated with an elastic consistency and showed a nodular appearance on the cut surface. Histological examination revealed thyroid tissue with the characteristics of colloid goiter. The postoperative (99m)Tc-pertechnetate scan showed the normal thyroid gland located in the usual pretracheal site. The absence of malignancy, at histology and immunohistochemistry, allows a metastatic nature of the mass to be ruled out, and accounts for a supernumerary thyroid. The occurrence of a parapharyngeal thyroid, although extremely rare, is worth bearing in mind as a possible ectopic location. This case also supports the hypothesized role of the lateral thyroid anlage in man deriving from the ultimo-branchial body in the morphogenesis of the lateral lobe of the thyroid gland. | lld:pubmed |
