title: An unusual case of hürthle cell carcinoma presenting as metastatic pleural disease 16 years after thyroidectomy.
abstract: BACKGROUND
  Hürthle cell carcinoma (HCC), a variant of a follicular carcinoma of the thyroid, is an aggressive type of differentiated thyroid cancer now considered a distinct pathologic entity. It may present as a low-grade tumor or as a more aggressive type. Prognosis depends on the age of the patient, tumor size, extent of invasion, and initial nodal or distant metastasis. Although thoracic involvement is not unusual with this tumor, this is the first report, to our knowledge, of latent pleural and lung metastases that were detected by a thoracentesis.
  
  
  METHODS
  A 63-year-old woman underwent total thyroidectomy for a thyroid mass in 1990 that was diagnosed as HCC. In December 2006, she presented with symptoms of dyspnea and an abnormal chest x-ray. A subsequent ultrasound-guided thoracentesis revealed a malignant, exudative effusion. Cytopathologic analysis revealed the malignancy to be consistent with HCC. She was reevaluated by her original oncologist and is undergoing treatment for metastatic HCC.
  
  
  CONCLUSIONS
  Although rare, HCC may present years after definitive therapy as metastatic pleural and lung disease. Further studies are needed to determine the cause of latency in such cases.
authors.affiliation: *Department of Interventional Pulmonary, Baylor College of Medicine, Houston, Texas †Department of Interventional Pulmonary, Johns Hopkins Hospital, Baltimore, Maryland ‡Interventional Pulmonology, Pulmonary and Critical Care Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts §Department of Otolaryngology, Head and Neck Surgery, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Nadine
authors.initials: N
authors.lastname: Bagherzadegan
authors.forename: David
authors.initials: D
authors.lastname: Feller-Kopman
authors.forename: Armin
authors.initials: A
authors.lastname: Ernst
authors.forename: Stephan
authors.initials: S
authors.lastname: Haerle
authors.forename: William
authors.initials: W
authors.lastname: Lunn