title: Morphological, diagnostic and surgical features of ectopic thyroid gland: a review of literature.
abstract: Ectopic thyroid tissue remains a rare developmental abnormality involving defective or aberrant embryogenesis of the thyroid gland during its passage from the floor of the primitive foregut to its usual final position in pre-tracheal region of the neck. Its specific prevalence accounts about 1 case per 100.000-300.000 persons and one in 4.000-8.000 patients with thyroid disease show this condition. The cause of this defect is not fully known. Despite genetic factors have been associated with thyroid gland morphogenesis and differentiation, just recently some mutation has been associated with human thyroid ectopy. Lingual region in the most common site of thyroid ectopy but ectopic thyroid tissue were found in other head and neck locations. Nevertheless, aberrant ectopic thyroid tissue has been found in other places distant from the neck region. Ectopic tissue is affected by different pathological changes that occur in the normal eutopic thyroid. Patients may present insidiously or as an emergency. Diagnostic management of thyroid ectopy is performed by radionuclide thyroid imaging, ultrasonography, CT scan, MRI, biopsy and thyroid function tests. Asymptomatic euthyroid patients with ectopic thyroid do not usually require therapy but are kept under observation. For those with symptoms, treatment depends on size of the gland, nature of symptoms, thyroid function status and histological findings. Surgical excision is often required as treatment for this condition.
authors.affiliation: Department of Medicine and Health Sciences, University of Molise, Via F. De Sanctis 1, 86100 Campobasso, Italy. Electronic address: germano.guerra@unimol.it.
authors.forename: Germano
authors.initials: G
authors.lastname: Guerra
authors.affiliation: Department of Public Health, University of Naples "Federico II", Naples, Italy.
authors.forename: Mariapia
authors.initials: M
authors.lastname: Cinelli
authors.affiliation: Department of Neuroscience Reproductive and Dentistry Sciences, Otholaryngology Unit, University of Naples "Federico II", Naples, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Mesolella
authors.affiliation: Department of Sport Sciences and Wellness, University of Naples "Parthenope", Naples, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Tafuri
authors.affiliation: Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples, Italy.
authors.forename: Aldo
authors.initials: A
authors.lastname: Rocca
authors.affiliation: Department of Clinical Medicine and Surgery, University of Naples "Federico II", Naples, Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: Amato
authors.affiliation: Department of Neuroscience Reproductive and Dentistry Sciences, Otholaryngology Unit, University of Naples "Federico II", Naples, Italy.
authors.forename: Sandro
authors.initials: S
authors.lastname: Rengo
authors.affiliation: Department of Anesthesiologic, Surgical and Emergency Sciences, Otolaryngology - Head and Neck Surgery Unit, Second University of Naples, Naples, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Testa
mesh_terms: D020022:Genetic Predisposition to Disease; D006257:Head; D006801:Humans; D009333:Neck; D050033:Thyroid Dysgenesis / Q000175:diagnosis* / Q000209:etiology / Q000601:surgery*; D013961:Thyroid Gland / Q000196:embryology
keywords: Ectopic tissue; Thyroid embryology; Thyroid gland; Thyroid surgical management