title: Hyperthyroidism due to coexistence of Graves' disease and Struma ovarii.
abstract: OBJECTIVE
  To report an unusual case of persistent thyrotoxicosis after treatment of Graves' disease, because of coexistence of struma ovarii.
  
  
  METHODS
  We report the clinical history, imaging studies, laboratory and pathologic data, and treatment in a patient with persistent hyperthyroidism after surgical treatment of Graves' disease. In addition, we discuss some aspects of the pathogenesis of hyperthyroidism due to functioning struma ovarii.
  
  
  RESULTS
  A 42-year-old woman underwent near-total thyroidectomy for treatment of Graves' disease. Post-operatively, hyperthyroidism was still present. Methimazole was administered again, and performance of a 131I whole-body scan demonstrated a focus of intense uptake in the pelvis. Pelvic ultrasonography revealed a mass (11 by 8 by 7.1 cm) arising from the right ovary, with both solid and cystic components. Abdominal surgical exploration was performed, and the final histologic diagnosis was struma ovarii. The symptoms of hyperthyroidism diminished, and 3 weeks postoperatively, the thyroid hormone levels were in the hypothyroid range.
  
  
  CONCLUSIONS
  In patients with refractory hyperthyroidism after thyroid surgical treatment, radioiodine scanning should be performed to diagnose or exclude the functioning profile of ovarian masses.
authors.affiliation: Department of Surgical Oncology, National Cancer Institute, Naples, Italy.
authors.forename: Maria G
authors.initials: MG
authors.lastname: Chiofalo
authors.forename: Claudia
authors.initials: C
authors.lastname: Misso
authors.forename: Luigi
authors.initials: L
authors.lastname: Insabato
authors.forename: Secondo
authors.initials: S
authors.lastname: Lastoria
authors.forename: Luciano
authors.initials: L
authors.lastname: Pezzullo
mesh_terms: D000328:Adult; D005260:Female; D006111:Graves Disease / Q000150:complications* / Q000628:therapy; D013509:Gynecologic Surgical Procedures; D006801:Humans; D010051:Ovarian Neoplasms / Q000150:complications* / Q000601:surgery; D013330:Struma Ovarii / Q000150:complications* / Q000601:surgery; D013965:Thyroidectomy; D013971:Thyrotoxicosis / Q000209:etiology* / Q000628:therapy