title: Adjuvant radioactive iodine therapy is associated with improved survival for patients with intermediate-risk papillary thyroid cancer.
abstract: BACKGROUND
  Papillary thyroid cancer (PTC) is the most common endocrine malignancy. The long-term prognosis is generally excellent. Due to a paucity of data, debate exists regarding the benefit of adjuvant radioactive iodine therapy (RAI) for intermediate-risk patients.
  
  
  OBJECTIVE
  The objective of the study was to examine the impact of RAI on overall survival in intermediate-risk PTC patients.
  
  
  METHODS
  Adult patients with intermediate-risk PTC who underwent total thyroidectomy with/without RAI in the National Cancer Database, 1998-2006, participated in the study.
  
  
  METHODS
  Intermediate-risk patients, as defined by American Thyroid Association risk and American Joint Commission on Cancer disease stage T3, N0, M0 or Mx, and T1-3, N1, M0, or Mx were included in the study. Patients with aggressive variants and multiple primaries were excluded.
  
  
  METHODS
  Overall survival (OS) for patients treated with and without RAI using univariate and multivariate regression analyses was measured.
  
  
  RESULTS
  A total of 21 870 patients were included; 15 418 (70.5%) received RAI and 6452 (29.5%) did not. Mean follow-up was 6 years, with the longest follow-up of 14 years. In an unadjusted analysis, RAI was associated with improved OS in all patients (P < .001) as well as in a subgroup analysis among patients younger than 45 years (n = 12 612, P = .002) and 65 years old and older (median OS 140 vs 128 mo, n = 2122, P = .008). After a multivariate adjustment for demographic and clinical factors, RAI was associated with a 29% reduction in the risk of death, with a hazard risk 0.71 (95% confidence interval 0.62-0.82, P < .001). For age younger than 45 years, RAI was associated with a 36% reduction in risk of death, with a hazard risk 0.64 (95% confidence interval 0.45- 0.92, P = .016).
  
  
  CONCLUSIONS
  This is the first nationally representative study of intermediate-risk PTC patients and RAI therapy demonstrating an association of RAI with improved overall survival. We recommend that this patient group should be considered for RAI therapy.
authors: Department of Medicine (E.R., J.M.P.), Division of Endocrinology, Metabolism, and Nutrition, Department of Surgery (J.A.S.), Section of Endocrine Surgery, Duke University Medical Center, and Duke Cancer Institute (J.A.S.), Durham, North Carolina 27710; Department of Biostatistics (S.T.), Duke University, Durham, North Carolina 27708; and Duke Clinical Research Institute (M.D., J.A.S.), Durham, North Carolina 27705.
authors: Ewa
authors: E
authors: Ruel
authors: Samantha
authors: S
authors: Thomas
authors: Michaela
authors: M
authors: Dinan
authors: Jennifer M
authors: JM
authors: Perkins
authors: Sanziana A
authors: SA
authors: Roman
authors: Julie Ann
authors: JA
authors: Sosa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000401:mortality* / Q000473:pathology / Q000532:radiotherapy*; D002291:Carcinoma, Papillary; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D018714:Radiotherapy, Adjuvant; D012008:Recurrence; D012720:Severity of Illness Index; D016019:Survival Analysis; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000401:mortality* / Q000473:pathology / Q000532:radiotherapy*; D013965:Thyroidectomy
chemical_list: D007457:Iodine Radioisotopes
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