title: Extent of surgery for papillary thyroid cancer is not associated with survival: an analysis of 61,775 patients.
abstract: OBJECTIVE
  To examine the association between the extent of surgery and overall survival in a large contemporary cohort of patients with papillary thyroid cancer (PTC).
  
  
  BACKGROUND
  Guidelines recommend total thyroidectomy for PTC tumors >1 cm, based on older data demonstrating an overall survival advantage for total thyroidectomy over lobectomy.
  
  
  METHODS
  Adult patients with PTC tumors 1.0-4.0 cm undergoing thyroidectomy in the National Cancer Database, 1998-2006, were included. Cox proportional hazards models were applied to measure the association between the extent of surgery and overall survival while adjusting for patient demographic and clinical factors, including comorbidities, extrathyroidal extension, multifocality, nodal and distant metastases, and radioactive iodine treatment.
  
  
  RESULTS
  Among 61,775 PTC patients, 54,926 underwent total thyroidectomy and 6849 lobectomy. Compared with lobectomy, patients undergoing total thyroidectomy had more nodal (7% vs 27%), extrathyroidal (5% vs 16%), and multifocal disease (29% vs 44%) (all Ps < 0.001). Median follow-up was 82 months (range, 60-179 months). After multivariable adjustment, overall survival was similar in patients undergoing total thyroidectomy versus lobectomy for tumors 1.0-4.0 cm [hazard ratio (HR) = 0.96; 95% confidence interval (CI), 0.84-1.09); P = 0.54] and when stratified by tumor size: 1.0-2.0 cm [HR = 1.05; 95% CI, 0.88-1.26; P = 0.61] and 2.1-4.0 cm [HR = 0.89; 95% CI, 0.73-1.07; P = 0.21]. Older age, male sex, black race, lower income, tumor size, and presence of nodal or distant metastases were independently associated with compromised survival (P < 0.0001).
  
  
  CONCLUSIONS
  Current guidelines suggest total thyroidectomy for PTC tumors >1 cm. However, we did not observe a survival advantage associated with total thyroidectomy compared with lobectomy. These findings call into question whether tumor size should be an absolute indication for total thyroidectomy.
authors.affiliation: *Department of Surgery, Duke University Medical Center †Department of Biostatistics, Duke University; and ‡Duke Clinical Research Institute.
authors.forename: Mohamed Abdelgadir
authors.initials: MA
authors.lastname: Adam
authors.forename: John
authors.initials: J
authors.lastname: Pura
authors.forename: Lin
authors.initials: L
authors.lastname: Gu
authors.forename: Michaela A
authors.initials: MA
authors.lastname: Dinan
authors.forename: Douglas S
authors.initials: DS
authors.lastname: Tyler
authors.forename: Shelby D
authors.initials: SD
authors.lastname: Reed
authors.forename: Randall
authors.initials: R
authors.lastname: Scheri
authors.forename: Sanziana A
authors.initials: SA
authors.lastname: Roman
authors.forename: Julie A
authors.initials: JA
authors.lastname: Sosa
mesh_terms: D000328:Adult; D002277:Carcinoma / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D002291:Carcinoma, Papillary / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D009362:Neoplasm Metastasis; D012307:Risk Factors; D016019:Survival Analysis; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D013965:Thyroidectomy / Q000379:methods*