title: Differences in the characteristics of papillary thyroid microcarcinoma ≤5 mm and >5 mm in diameter.
abstract: BACKGROUND
  The behavior and optimal management of papillary thyroid microcarcinomas (PTMCs) after thyroidectomy remain unclear. The purpose of this study was to compare the clinicopathologic features and tumor recurrence rates of patients with PTMCs ≤5 mm and >5 mm in diameter after total thyroidectomy.
  
  
  METHODS
  A group of patients with PTMCs ≤5 mm (n=83) has been compared to a group with >5 mm (n=122). All of these patients had conventional type PTMCs and were followed up for 5 years. Both the histology and the outcome have been compared.
  
  
  RESULTS
  Sex (p=.014) and extrathyroidal extension (p=.003) of patients in the ≤5 mm and >5 mm groups differed significantly. Two and 5 patients from these groups, respectively, experienced tumor recurrence within 5 years (2.4% vs 4.1%; p=.634).
  
  
  CONCLUSIONS
  The clinicopathologic features of PTMCs ≤5 mm and >5 mm are similar, except for sex distribution and extrathyroidal extension. The 5-year recurrence rate in the 2 groups did not differ significantly.
authors.affiliation: Division of Surgery, Thyroid Center, National Medical Center, Seoul, Korea.
authors.forename: Eunyoung
authors.initials: E
authors.lastname: Kim
authors.forename: June Young
authors.initials: JY
authors.lastname: Choi
authors.forename: Do Hoon
authors.initials: do H
authors.lastname: Koo
authors.forename: Kyu Eun
authors.initials: KE
authors.lastname: Lee
authors.forename: Yeo-Kyu
authors.initials: YK
authors.lastname: Youn
mesh_terms: D000328:Adult; D001707:Biopsy, Needle; D002291:Carcinoma, Papillary / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D015331:Cohort Studies; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology*; D009367:Neoplasm Staging; D056910:Republic of Korea; D012189:Retrospective Studies; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D015996:Survival Rate; D013964:Thyroid Neoplasms / Q000401:mortality / Q000473:pathology* / Q000601:surgery*; D013965:Thyroidectomy / Q000379:methods; D016896:Treatment Outcome; D047368:Tumor Burden
keywords: clinicopathological features; papillary thyroid microcarcinoma; recurrence; surgery; total thyroidectomy