title: Predictive factors of contralateral paratracheal lymph node metastasis in unilateral papillary thyroid carcinoma.
abstract: BACKGROUND
  Most of unilateral papillary thyroid carcinoma (PTC) metastasize to ipsilateral paratracheal lymph nodes (LNs) while some had contralateral paratracheal LN involved. The aim of this study was to analyze the predictive factors of contralateral paratracheal LN metastasis in unilateral PTC.
  
  
  METHODS
  Data on 332 patients with unilateral PTC who underwent total/near total thyroidectomy and bilateral central neck dissection (CND) with/without lateral neck dissection were collected retrospectively. Patients' demographics, the extent of surgeries, and the pathological status of LNs and primary tumor were analyzed.
  
  
  RESULTS
  A total of 332 patients (67 male and 265 female) were included. Contralateral paratracheal LN metastasis was found in 68 (68/332, 20.5%) patients. Tumor size (>1 cm) (P < .001), capsular/extracapsular invasion (P < .001), pretracheal/prelaryngeal LN metastasis (P < .001), lateral neck LN metastasis (P < .001) and ipsilateral paratracheal LN metastasis (P < .001) was significantly associated with contralateral paratracheal LN metastasis on univariate analysis. Multivariate analysis showed that tumor size (>1 cm) (P = .013), capsular/extracapsular invasion (P = .009), pretracheal/prelaryngeal LN metastasis (P = .021) and lateral neck LN metastasis (P = .002) were independent risk factors of contralateral paratracheal LN metastasis.
  
  
  CONCLUSIONS
  Primary tumor size >1 cm, capsular/extracapsular invasion, pretracheal/prelaryngeal LN metastasis and lateral neck LN metastasis are predictive factors of contralateral paratracheal LN metastasis in unilateral PTC, which may help to determine the optimal extent of CND in patients with PTC.
authors.affiliation: Department of Thyroid & Breast Surgery, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China.
authors.forename: T
authors.initials: T
authors.lastname: Wei
authors.affiliation: Department of Thyroid & Breast Surgery, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China.
authors.forename: R
authors.initials: R
authors.lastname: Chen
authors.affiliation: Department of Thyroid & Breast Surgery, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China.
authors.forename: X
authors.initials: X
authors.lastname: Zou
authors.affiliation: Department of Thyroid & Breast Surgery, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China.
authors.forename: F
authors.initials: F
authors.lastname: Liu
authors.affiliation: Department of Thyroid & Breast Surgery, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China.
authors.forename: Z
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Thyroid & Breast Surgery, West China Hospital, Sichuan University, Chengdu 610041, Sichuan Province, China. Electronic address: zjq-wkys@163.com.
authors.forename: J
authors.initials: J
authors.lastname: Zhu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000473:pathology* / Q000556:secondary / Q000601:surgery; D002291:Carcinoma, Papillary; D002648:Child; D005260:Female; D006801:Humans; D007830:Larynx; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009333:Neck; D037981:Neck Dissection; D009361:Neoplasm Invasiveness; D012189:Retrospective Studies; D012307:Risk Factors; D000077273:Thyroid Cancer, Papillary; D013964:Thyroid Neoplasms / Q000473:pathology* / Q000601:surgery; D013965:Thyroidectomy; D014132:Trachea; D047368:Tumor Burden; D055815:Young Adult
keywords: Central neck dissection; Lateral neck dissection; Lymph node; Papillary; Predictive factor; Thyroid carcinoma