title: Number of tumor foci as predictor of lateral lymph node metastasis in papillary thyroid carcinoma.
abstract: BACKGROUND
  The purpose of this study was to determine the clinicopathologic characteristics of patients with papillary thyroid carcinoma (PTC) by the number of tumor foci.
  
  
  METHODS
  A retrospective analysis of 2095 patients with PTC was performed. The study population was divided into 4 groups based on the number of tumor foci: N1 (1 tumor focus), N2 (2 foci), N3 (3 foci), and N4 (4 or more foci).
  
  
  RESULTS
  An increasing number of tumor foci was significantly associated with older age at diagnosis (p = .006), cervical lymph node metastasis (p < .001), and advanced TNM stage of disease (p = .001) at initial surgery. The multivariate adjusted odds ratios (ORs) and 95% confidence intervals (95% CIs) for the N2, N3, and N4 groups compared to the N1 group for lateral lymph node metastasis were OR 1.53 (95% CI, 1.05-2.22), OR 2.57 (95% CI, 1.50-4.42), and OR 2.88 (95% CI, 1.42-5.84), respectively.
  
  
  CONCLUSIONS
  An increase in the number of tumor foci was strongly associated with older age at diagnosis, cervical lymph node metastasis, and advanced TNM stage of PTC. The number of tumor foci independently predicted lateral lymph node metastasis.
authors.affiliation: Division of Endocrinology and Metabolism, Department of Internal Medicine, Soonchunhyang University Hospital, Soonchunhyang University College of Medicine, Seoul, Korea.
authors.forename: Hye Jeong
authors.initials: HJ
authors.lastname: Kim
authors.forename: Hyeong Kyu
authors.initials: HK
authors.lastname: Park
authors.forename: Dong Won
authors.initials: DW
authors.lastname: Byun
authors.forename: Kyoil
authors.initials: K
authors.lastname: Suh
authors.forename: Myung Hi
authors.initials: MH
authors.lastname: Yoo
authors.forename: Yong-Ki
authors.initials: YK
authors.lastname: Min
authors.forename: Sun Wook
authors.initials: SW
authors.lastname: Kim
authors.forename: Jae Hoon
authors.initials: JH
authors.lastname: Chung
mesh_terms: D000328:Adult; D000368:Aged; D001707:Biopsy, Needle; D002277:Carcinoma / Q000401:mortality / Q000556:secondary* / Q000601:surgery; D002291:Carcinoma, Papillary; D015331:Cohort Studies; D016001:Confidence Intervals; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008197:Lymph Node Excision / Q000379:methods; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness / Q000473:pathology; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology*; D009367:Neoplasm Staging; D011379:Prognosis; D012189:Retrospective Studies; D018570:Risk Assessment; D016019:Survival Analysis; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000401:mortality / Q000473:pathology* / Q000556:secondary / Q000601:surgery; D013965:Thyroidectomy / Q000379:methods*; D055815:Young Adult
keywords: lymph node metastasis; multifocality; papillary thyroid carcinoma