Benign ectopic thyroid tissue in a cutaneous location: a case report and review

Authors


Kathleen J. Smith, COL, MC USA, Department of Dermatology and Pathology, University of Alabama, EFH Suite 414, 1720 University Blvd, Birmingham, AL 35294-0009, USA
Tel: +1 205 975 6964
Fax: +1 205 975 6922
e-mail: henry.g.skelton@questdiagnostics.com

Abstract

Background:  For many years, lateral, aberrant thyroid tissue in adults was a term used almost exclusively for metastatic thyroid carcinoma. However, aberrant, benign ectopic thyroid tissue does occur, and it is most commonly found as a part of the evaluation of endocrine dysfunction. Rarely, aberrant, benign ectopic thyroid presents as a primary mass.

Case report:  We present a 35-year-old female who presented for removal of a lifelong posterior lateral neck nodule.

Results:  Histologic examination and immunohistochemical studies confirmed the presence of aberrant, benign ectopic thyroid tissue. The patient had no endocrine problems, and she had a normally located and functioning thyroid gland.

Conclusions:  This case illustrates that not all aberrant thyroid tissues in adults are malignant or associated with endocrine disorders. This case also illustrates the rare association of ectopic thyroid and a normally located and functioning thyroid gland. In this patient, a somatic mutation in a transcription factor important in thyroid migration could explain these findings.

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