title: Prediction of ipsilateral and contralateral central lymph node metastasis in unilateral papillary thyroid carcinoma: a retrospective study.
abstract: BACKGROUND
  Prophylactic central lymph node dissection (CLND) in patients with papillary thyroid carcinoma (PTC) remains controversial and predictive factors for central lymph node (CLN) metastasis in unilateral PTC cases are not well defined. The aims of this study were to evaluate the rate of ipsilateral and contralateral CLN metastasis and to determine the clinicopathologic factors predictive for ipsilateral and contralateral CLN metastasis in unilateral PTC cases.
  
  
  METHODS
  We retrospectively reviewed 218 PTC patients with clinically negative-node neck who have received total thyroidectomy with bilateral CLND. Pearson χ(2) test or Fisher exact test and multivariate analysis were used to evaluate relationships between CLN metastasis and demographic factors such as age, sex and the clinicopathologic factors.
  
  
  RESULTS
  Ipsilateral and contralateral CLN metastasis were present in 47.7% (104/218) and 13.3% (29/218), respectively. Multivariate analysis showed that tumor size (>1 cm) (P=0.016; OR, 2.005) and age <45 years old (P=0.031; OR, 1.539) were the predictors of ipsilateral CLN metastasis, and prelaryngeal lymph node (LN) metastasis (P=0.028; OR, 2.970) and ipsilateral CLN metastasis (P<0.001; OR, 15.128) independently predicted contralateral CLN metastasis.
  
  
  CONCLUSIONS
  CLN metastasis was common in PTC patients with clinically node-negative neck and the most common pattern of CLN metastasis was ipsilateral CLN metastasis. Prophylactic ipsilateral CLND may be an optional procedure and should be considered for patients with a tumor size >1 cm. Therapeutic bilateral CLND should be considered in patients with a tumor size >1 cm and especially, if there exists prelaryngeal LN or ipsilateral CLN metastasis on frozen section analysis.
authors: Department of Thyroid and Breast Surgery, West China Hospital, Sichuan University, Chengdu 610041, China.
authors: Qiang
authors: Q
authors: Chen
authors: Department of Thyroid and Breast Surgery, West China Hospital, Sichuan University, Chengdu 610041, China.
authors: Xiu-He
authors: XH
authors: Zou
authors: Department of Thyroid and Breast Surgery, West China Hospital, Sichuan University, Chengdu 610041, China.
authors: Tao
authors: T
authors: Wei
authors: Department of Thyroid and Breast Surgery, West China Hospital, Sichuan University, Chengdu 610041, China.
authors: Qiu-Shi
authors: QS
authors: Huang
authors: Department of Thyroid and Breast Surgery, West China Hospital, Sichuan University, Chengdu 610041, China.
authors: Ying-He
authors: YH
authors: Sun
authors: Department of Thyroid and Breast Surgery, West China Hospital, Sichuan University, Chengdu 610041, China.
authors: Jing-Qiang
authors: JQ
authors: Zhu
keywords: Papillary thyroid carcinoma (PTC); lymph node (LN) metastasis; prophylactic central lymph node dissection (CLND)