Ectopic thyroid presenting as supraclavicular mass: A case report and literature review

Ectopic thyroid tissue most commonly presents along the midline neck, from the base of tongue to the mediastinum, as a result of embryologic descent of the gland. When thyroid tissue is found in unusual locations, there is concern for malignant metastases, particularly in areas with rich lymphatic or vascular networks. A 76-year-old female presented with a large multinodular thyroid and a separate left shoulder mass. She reported a distant history of thyroid surgery in Haiti. After a workup including CT of the neck and FNA biopsy, both masses were resected. Histopathological examination revealed both masses to be benign multi-nodular goiters. To the authors’ knowledge, this is the first report of ectopic thyroid tissue within the deltopectoral musculature. While there are a number of possible explanations, the most likely etiology in this case is the seeding of thyroid tissue during parathyroid auto-transplantation 30 years prior to presentation.