title: Risk factors contributing to the difference in prognosis for papillary versus micropapillary thyroid carcinoma.
abstract: BACKGROUND
  The aggressiveness of papillary thyroid carcinoma (PTC) was evaluated by comparing conventional PTC with papillary thyroid microcarcinoma (PTMC). Risk factors associated with differences in clinical and pathologic features were analyzed to provide appropriate surgical management.
  
  
  METHODS
  A total of 539 patients with papillary carcinoma who underwent total thyroidectomy were retrospectively reviewed. The median follow-up period was 32 months.
  
  
  RESULTS
  Of 539 patients, 311 (57.7%) had PTMC, and 228 (42.3%) had conventional PTC. No differences between patients with PTMC and those with PTC were observed in age, gender, and multifocality. PTMC was associated with less frequent bilaterality (P = .002), lymph node metastasis (P < .001), thyroid capsule invasion (P < .001), and disease recurrence (P < .001), and a higher rate of incidental diagnosis (P = .001). There was no statistically significant difference between the prevalence of lymph node metastasis at diagnosis and disease recurrence rate between nonincidental PTMC and conventional PTC (P > .05).
  
  
  CONCLUSIONS
  Incidental PTMC had significantly fewer aggressive tumor features. Nonincidental PTMC presented with aggressive characteristics similar to those of conventional PTC and should be treated likewise. The authors suggest routine total thyroidectomy followed by an adequate exploration of the central neck compartment as a safe treatment.
authors.affiliation: Second Department of Propedeutic Surgery, School of Medicine, University of Athens, Laikon General Hospital, Athens, Greece.
authors.forename: Theodore
authors.initials: T
authors.lastname: Karatzas
authors.forename: Ioannis
authors.initials: I
authors.lastname: Vasileiadis
authors.forename: Stylianos
authors.initials: S
authors.lastname: Kapetanakis
authors.forename: Efthimios
authors.initials: E
authors.lastname: Karakostas
authors.forename: George
authors.initials: G
authors.lastname: Chrousos
authors.forename: Gregory
authors.initials: G
authors.lastname: Kouraklis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002291:Carcinoma, Papillary / Q000473:pathology* / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D033162:Incidental Findings; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009364:Neoplasm Recurrence, Local; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D013964:Thyroid Neoplasms / Q000473:pathology* / Q000601:surgery*; D013965:Thyroidectomy; D055815:Young Adult
keywords: Papillary thyroid carcinoma; Papillary thyroid microcarcinoma; Prognosis; Risk factors