Rationale: A symptomatic mass in the thymus is due to anomalies in the development of the pharyngeal pouches and is also an unusual cause of consultation. These anomalies may be found anywhere along the natural path of the embryonic thymus, from the angle of the jaw to the upper mediastinum.
Aim: To review the epidemiology, pathogenesis, diagnosis, and management of congenital anomalies of thymic origin in the neck.
Material and method: A MEDLINE search was carried out, using the Cochrane methodology, for articles published from January 1980 to January 2007 using the terms "thymus gland," "cervical mass." Following this bibliographical search, the texts considered most relevant by the authors were selected.
Conclusions: While this anomaly is relatively common, its level of presentation is very low and it should always be considered in the differential diagnosis of congenital masses in the neck. New diagnostic imaging techniques provide an early and more accurate diagnosis, thus allowing a better outcome in these patients.