ectopic cervical thymus (ect) is an essentially benign condition that is identified during the development of the thymus, and is rare among the adult population. thymic hyperplasia is another thymus-associated condition, which is known to occur secondary to hyperthyroidism. a 39-year-old woman with hyperthyroidism presented with an enlarging submandibular mass, which was diagnosed as a benign h...

BACKGROUND The incidence of aberrant thymus in the posterior mediastinum is very uncommon. It is difficult to exclude malignancy before surgical procedure. CASE PRESENTATION In a six-month-old male coughing for two weeks prior to admission a posterior mediastinal mass was found incidentally by chest roentgenogram. Thoracotomy was performed. Histologic study revealed normal thymic tissue. CO...

The thymus and parathyroid glands arise from a shared endodermal primordium in the third pharyngeal pouch (3rd pp). Thymus fate is specified in the ventral 3rd pp between E9.5 and E11, whereas parathyroid fate is specified in the dorsal domain. The molecular mechanisms that specify fate and regulate thymus and parathyroid development are not fully delineated. Previous reports suggested that Tbx...

Cervical ectopic thymus occurs when thymic tissue arrests during its embryologic descent through the neck to the upper mediastinum. Most often it presents as an asymptomatic neck mass. Rarely does it present with airway compromise, particularly in neonates. A neonate presented with a retropharyngeal mass causing dynamic upper airway obstruction, mimicking a venolymphatic malformation. Ultimatel...

Intrathyroidal thymic tissue is rare and may be confused with a malignant thyroid nodule because of hyperechoic dots mimicking calcifications. We report the case of a thyroid nodule with malignant ultrasonographic findings in a 4-year-old child, which was confirmed cytologically as ectopic thymic tissue. The sonographic findings of ectopic thymus were similar to those of the thymus; therefore, ...

Humans expressing a defective form of the transcription factor AIRE (autoimmune regulator) develop multiorgan autoimmune disease. We used aire- deficient mice to test the hypothesis that this transcription factor regulates autoimmunity by promoting the ectopic expression of peripheral tissue- restricted antigens in medullary epithelial cells of the thymus. This hypothesis proved correct. The mu...

In the embryo, the thymus originates from the third and fourth pharyngeal pouches and migrates from the superior neck to the mediastinum. Ectopic cervical thymoma (ECT) is an extremely rare tumor that originates from ectopic tissue, and is caused by the aberrant migration of the embryonic thymus. Our patient was a 30-year-old woman who had a nodular lesion in the neck for several years. Ultraso...

The aim of this study is to report a case of agenesis of the isthmus of the thyroid gland, and ectopic locations of the inferior parathyroid glands and thymus observed in an 80-year old female cadaver during routine dissection of the head and neck. The two lobes of the thyroid gland were small and connected by pretracheal fascia at the midline, which upon histological study were seen to contain...