title: Predictive factors of central lymph node metastasis in papillary thyroid carcinoma.
abstract: OBJECTIVE
  The aim of this study was to evaluate the correlation between central lymph node (CLN) metastasis and clinicopathologic characteristics of papillary thyroid cancer (PTC). In addition, we investigated the incidence and risk factors for contralateral CLN metastasis in unilateral PTC. This study suggests the appropriate surgical extent for CLN dissection.
  
  
  METHODS
  A prospective study of 500 patients with PTC who underwent total thyroidectomy and prophylactic bilateral CLN dissection was conducted.
  
  
  RESULTS
  Of 500 patients, 255 had CLN metastases. The rate of CLN metastasis was considerably higher in cases of younger patients (<45 years old) (P < 0.001; odds ratio [OR], 2.357) and of a maximal tumor size greater than 1 cm (P < 0.001; OR, 3.165). Ipsilateral CLN metastasis was detected in 83.1% of cases (133/160) of unilateral PTC, only contralateral CLN metastases in 3.7% of cases (6/160), and bilateral CLN metastases in 13.1% of cases (21/160). The rate of contralateral CLN metastasis was considerably higher in cases of PTC with a large tumor size (≥1 cm) (P = 0.019; OR, 4.440) and with ipsilateral CLN metastasis (P = 0.047; OR, 2.613).
  
  
  CONCLUSIONS
  Younger age (<45 years old) and maximal tumor size greater than 1 cm were independent risk factors for CLN metastasis. Maximal tumor size greater than 1 cm and presence of ipsilateral CLN macrometastasis were independent risk factors for contralateral CLN metastasis. Therefore, both CLN dissections should be considered for unilateral PTC with a maximal tumor size greater than 1 cm or presence of ipsilateral CLN macrometastasis.
authors.affiliation: Department of Surgery, Chungnam National University College of Medicine, Daejeon, Korea.
authors.forename: Byong Hyon
authors.initials: BH
authors.lastname: Ahn
authors.affiliation: Department of Surgery, Chungnam National University College of Medicine, Daejeon, Korea.
authors.forename: Je Ryong
authors.initials: JR
authors.lastname: Kim
authors.affiliation: Department of Surgery, Chungnam National University College of Medicine, Daejeon, Korea.
authors.forename: Ho Chul
authors.initials: HC
authors.lastname: Jeong
authors.affiliation: Department of Surgery, Chungnam National University College of Medicine, Daejeon, Korea.
authors.forename: Jin Sun
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Surgery, Chungnam National University College of Medicine, Daejeon, Korea.
authors.forename: Eil Sung
authors.initials: ES
authors.lastname: Chang
authors.affiliation: Department of Surgery, Konkuk University Chungju Hospital, Chungju, Korea.
authors.forename: Yong Hun
authors.initials: YH
authors.lastname: Kim
keywords: Lymph node; Metastasis; Papillary thyroid cancer