A Papillary Carcinoma on Intranodal Thyroid Ectopy

Thyroid ectopy is a rare pathology associated with a failure of the thyroid gland to migrate during embryonic development. It is characterized by the persistence of a thyroid remnant along the thyroglossal tract. We report a case of papillary carcinoma with lymph node metastasis developed on intranodal thyroid ectopy. This is a 27-year-old patient who underwent excision of a right laterocervical adenopathy, the histopathological examination of which revealed a papillary carcinoma of thyroid origin (PTC). Total thyroidectomy with lymph node dissection revealed normal thyroid parenchyma and upper mediastinal lymph node metastasis. The originality of this observation lies in the exceptional nature of this intranodal localization of thyroid tissue transformed into metastatic papillary thyroid carcinoma with normal thyroid parenchyma.