title: Toxic nodular goiter and cancer: a compelling case for thyroidectomy.
abstract: BACKGROUND
  Recent American Thyroid Association guidelines call for thyroidectomy or (131)I (Recommendation 31) in managing hyperthyroidism due to toxic nodular goiter (TNG). Concern for concomitant malignancy favors surgery. A 3 % thyroid cancer incidence in TNG patients has been reported, yet recent studies suggest this rate is underestimated. This multi-institutional study examined cancer incidence in TNG patients referred to surgery.
  
  
  METHODS
  Patients referred for thyroidectomy at three tertiary-care institutions were included (2002-2011). Patients with concurrent indeterminate or malignant diagnosis by fine-needle aspiration (FNA) were excluded. Cancer incidence in TNG patients was determined. Fisher's exact and chi-square tests and nonparametric t tests were used.
  
  
  RESULTS
  Among 2,551 surgically treated patients, 164 had TNG (6.4 %). Median age at presentation was 49.7 years, and 86 % were female. Overall cancer incidence was 18.3 % (30 of 164), and rates were not significantly different between institutions. A significantly greater cancer rate was noted in toxic multinodular goiter versus single toxic nodule patients (21 vs. 4.5 %, P < 0.05). Mean tumor size was 0.71 cm (range 0.1-1.5 cm; 23 % ≥1 cm). Most patients underwent total or near-total thyroidectomy. There were no significant differences in tumor sizes among institutions (P > 0.05). No significant cancer association was noted with age, preoperative dominant nodule size, lymphocytic thyroiditis or preoperative FNA (P > 0.05).
  
  
  CONCLUSIONS
  These data demonstrate a higher than expected incidental cancer rate in TNG patients compared to historical reports (18.3 vs. 3 %). This higher cancer incidence may alter the risk/benefit analysis regarding TNG treatment. This information should be provided to TNG patients before decision making regarding treatment.
authors.affiliation: Department of Surgery, Vanderbilt University Medical Center, Nashville, TN, USA.
authors.forename: J Joshua
authors.initials: JJ
authors.lastname: Smith
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.forename: David F
authors.initials: DF
authors.lastname: Schneider
authors.forename: Ratnam
authors.initials: R
authors.lastname: Nookala
authors.forename: James T
authors.initials: JT
authors.lastname: Broome
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Sippel
authors.forename: Herbert
authors.initials: H
authors.lastname: Chen
authors.forename: Carmen C
authors.initials: CC
authors.lastname: Solorzano
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D044963:Biopsy, Fine-Needle; D005260:Female; D005500:Follow-Up Studies; D006044:Goiter, Nodular / Q000473:pathology / Q000601:surgery*; D006801:Humans; D006980:Hyperthyroidism / Q000473:pathology / Q000601:surgery*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D011446:Prospective Studies; D012189:Retrospective Studies; D013964:Thyroid Neoplasms / Q000453:epidemiology* / Q000209:etiology; D013965:Thyroidectomy / Q000009:adverse effects*; D014481:United States / Q000453:epidemiology; D055815:Young Adult