title: TIMING OF RADIOACTIVE IODINE THERAPY DOES NOT IMPACT OVERALL SURVIVAL IN HIGH-RISK PAPILLARY THYROID CARCINOMA.
abstract: OBJECTIVE
  Postthyroidectomy radioiodine (RAI) therapy is indicated for papillary thyroid carcinoma (PTC) with high-risk features. There is variability in the timing of RAI therapy with no consensus. We analyzed the impact of the timing of initial RAI therapy on overall survival (OS) in PTC.
  
  
  METHODS
  The National Cancer Data Base (NCDB) was queried from 2003 to 2006 for patients with PTC undergoing near/subtotal or total thyroidectomy and RAI therapy. High-risk patients had tumors >4 cm in size, lymph node involvement, or grossly positive margins. Early RAI was ≤3 months, whereas delayed was between 3 and 12 months after thyroidectomy. Kaplan-Meier (KM) and Cox survival analyses were performed after adjusting for patient and tumor-related variables. A propensity-matched set of high-risk patients after eliminating bias in RAI timing was also analyzed.
  
  
  RESULTS
  There were 9,706 patients in the high-risk group. The median survival was 74.7 months. KM analysis showed a survival benefit for early RAI in high-risk patients (P = .025). However, this difference disappeared (hazard ratio [HR] 1.26, 95% confidence interval [CI] 0.98-1.62, P = .07) on adjusted Cox multivariable analysis. Timing of RAI therapy failed to affect OS in propensity-matched high-risk patients (HR 1.09, 95% CI 0.75-1.58, P = .662).
  
  
  CONCLUSIONS
  The timing of postthyroidectomy initial RAI therapy does not affect OS in patients with high-risk PTC.
  
  
  BACKGROUND
  CI = confidence interval CLNM = cervical lymph node metastasis FVPTC = follicular variant papillary thyroid carcinoma HR = hazard ratio KM = Kaplan-Meier NCDB = National Cancer Data Base OS = overall survival PTC = papillary thyroid carcinoma RAI = radioactive iodine.
authors.forename: Paritosh
authors.initials: P
authors.lastname: Suman
authors.forename: Chi-Hsiung
authors.initials: CH
authors.lastname: Wang
authors.forename: ShabirHusain S
authors.initials: SS
authors.lastname: Abadin
authors.forename: Romy
authors.initials: R
authors.lastname: Block
authors.forename: Vathsala
authors.initials: V
authors.lastname: Raghavan
authors.forename: Tricia A
authors.initials: TA
authors.lastname: Moo-Young
authors.forename: Richard A
authors.initials: RA
authors.lastname: Prinz
authors.forename: David J
authors.initials: DJ
authors.lastname: Winchester
mesh_terms: D000328:Adult; D002277:Carcinoma / Q000401:mortality / Q000532:radiotherapy*; D002291:Carcinoma, Papillary; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D013965:Thyroidectomy; D013997:Time Factors
chemical_list: D007457:Iodine Radioisotopes