title: Number of central lymph node metastasis for predicting lateral lymph node metastasis in papillary thyroid microcarcinoma.
abstract: BACKGROUND
  The purpose of this study was to present our evaluation of the relationship between the number of positive central lymph nodes and lateral lymph node metastasis in patients with papillary thyroid microcarcinoma (PTMC).
  
  
  METHODS
  Up to 141 patients with PTMC were divided into 3 groups according to different positive central lymph node classifications as follows: group A, no positive central lymph node; group B, 1 positive central lymph node; and group C, 2 or more positive central lymph nodes.
  
  
  RESULTS
  Incidence of lateral lymph node metastasis was 30.5% (43 of 141). It was significantly high in group C compared with groups A and B, although there was no significant difference between groups A and B. Number of positive central lymph node ≥2, underlying Hashimoto thyroiditis, and extrathyroidal extension were the independent predictive factors for lateral lymph node metastasis on multivariate analysis.
  
  
  CONCLUSIONS
  Lateral lymph node metastasis was mainly observed in patients with ≥2 positive central lymph nodes, which is an independent predictive factor for lateral lymph node metastasis. Therefore, ≥2 positive central lymph nodes may be valuable in predicting lateral lymph node metastasis.
authors.affiliation: Department of Oncology, The First Affiliated Hospital of Wenzhou Medical College, Wenzhou City, Zhejiang Province, People's Republic of China.
authors.forename: Rui-chao
authors.initials: RC
authors.lastname: Zeng
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Er-li
authors.initials: EL
authors.lastname: Gao
authors.forename: Pu
authors.initials: P
authors.lastname: Cheng
authors.forename: Guan-li
authors.initials: GL
authors.lastname: Huang
authors.forename: Xiao-hua
authors.initials: XH
authors.lastname: Zhang
authors.forename: Quan
authors.initials: Q
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D002291:Carcinoma, Papillary / Q000556:secondary* / Q000601:surgery; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D016015:Logistic Models; D008197:Lymph Node Excision / Q000379:methods / Q000706:statistics & numerical data*; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D018709:Statistics, Nonparametric; D013964:Thyroid Neoplasms / Q000473:pathology* / Q000556:secondary / Q000601:surgery; D013965:Thyroidectomy; D016896:Treatment Outcome
keywords: central lymph node metastasis; lateral lymph node metastasis; lymph node; number of positive central lymph node; papillary thyroid microcarcinoma