title: Metastasis to the Thyroid Gland: A Critical Review.
abstract: BACKGROUND
  Metastasis to the thyroid gland from nonthyroid sites is an uncommon clinical presentation in surgical practice. The aim of this review was to assess its incidence management and outcomes.
  
  
  METHODS
  A literature review was performed to identify reports of metastases to the thyroid gland. Both clinical and autopsy series were included.
  
  
  RESULTS
  Metastases to the gland may be discovered at the time of diagnosis of the primary tumor, after preoperative investigation of a neck mass, or on histologic examination of a thyroidectomy specimen. The most common primary tumors in autopsy studies are from the lung. In clinical series, renal cell carcinoma is most common. For patients with widespread metastases in the setting of an aggressive malignancy, surgery is rarely indicated. However, when patients present with an isolated metastasis diagnosed during follow-up of indolent disease, surgery may achieve control of the central neck and even long-term cure. Other prognosticators include features of the primary tumor, time interval between initial diagnosis and metastasis, and extrathyroid extent of disease.
  
  
  CONCLUSIONS
  In patients with thyroid metastases, communication among clinicians treating the thyroid and the index primary tumor is essential. The setting is complex, and decisions must be made considering the features of the primary tumor, overall burden of metastases, and comorbidities. Careful balancing of these factors influences individualized approaches.
authors.affiliation: ENT Department, NHS Lothian, Lauriston Building, Lauriston Place, Edinburgh, UK. iainjnixon@nhs.net.
authors.forename: Iain J
authors.initials: IJ
authors.lastname: Nixon
authors.affiliation: Department of Otolaryngology, Hospital Universitario Central de Asturias, Oviedo, Spain.
authors.forename: Andrés
authors.initials: A
authors.lastname: Coca-Pelaz
authors.affiliation: ENT Department, East and North Hertfordshire Trust, Stevenage, UK.
authors.forename: Anna I
authors.initials: AI
authors.lastname: Kaleva
authors.affiliation: Oral and Maxillofacial Pathology, School of Dentistry, University of Liverpool, Liverpool, UK.|Department of Cellular Pathology, Liverpool Clinical Laboratories, Liverpool, UK.
authors.forename: Asterios
authors.initials: A
authors.lastname: Triantafyllou
authors.affiliation: Department of Surgery and MacLean Center for Clinical Ethics, The University of Chicago Medicine, Chicago, IL, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Angelos
authors.affiliation: Division of Surgical Oncology, Department of Surgery, Mount Sinai School of Medicine, New York, NY, USA.
authors.forename: Randall P
authors.initials: RP
authors.lastname: Owen
authors.affiliation: University of Udine, Udine, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Rinaldo
authors.affiliation: Head and Neck Surgery, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
authors.forename: Ashok R
authors.initials: AR
authors.lastname: Shaha
authors.affiliation: Department of Surgery, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, USA.
authors.forename: Carl E
authors.initials: CE
authors.lastname: Silver
authors.affiliation: International Head and Neck Scientific Group, Padua, Italy.
authors.forename: Alfio
authors.initials: A
authors.lastname: Ferlito
mesh_terms: D006801:Humans; D009369:Neoplasms / Q000473:pathology*; D013964:Thyroid Neoplasms / Q000556:secondary*