title: Risk factors analyses for lateral lymph node metastases in papillary thyroid carcinomas: a retrospective study of 356 patients.
abstract: The aim of this study was to investigate the incidence and risk factors for lateral lymph node metastasis (LLNM) in patients with papillary thyroid carcinoma (PTC).
  
  
  
  356 patients diagnosed with PTC who underwent total thyroidectomy and central lymph node dissection and lateral lymph node dissection between January 2005 and December 2011 were enrolled. The relation between LLNM and clinicopathological features such as gender, age, tumor size, tumor spread, psammoma bodies, tumor multifocality, extrathyroidal extension (ETE), unilateral or bilateral disease, tumor primary location and central lymph node metastases (CLNM) was analyzed.
  
  
  
  The rate of LLNM was 75.0%. In the univariate analysis, it was significantly associated with age, tumor size, tumor spread, extrathyroidal extension, primary tumor location and central lymph node metastasis (p < 0.05). In contrast, in the multivariate analysis, it was significantly associated with primary tumor location, central lymph node metastasis (p < 0.05) and tumor size > 1.5 cm with p = 0.05 but was unrelated to the other factors.
  
  
  
  Patients with PTC, with the primary tumor located in the upper part of the lobe and positive central compartment lymph node metastasis with a tumor size > 1.5 cm diameter are more likely to have LLNM. Therefore, more meticulous evaluations including the lateral lymph nodes should be performed before surgery.
authors.affiliation: Department of Head and Neck Surgery, Zhejiang Cancer Hospital, 38 Guangji Road, Hangzhou, 310022, China.
authors.forename: Xilin
authors.initials: X
authors.lastname: Nie
authors.affiliation: Department of Head and Neck Surgery, Zhejiang Cancer Hospital, 38 Guangji Road, Hangzhou, 310022, China.
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Tan
authors.affiliation: Department of Head and Neck Surgery, Zhejiang Cancer Hospital, 38 Guangji Road, Hangzhou, 310022, China.
authors.forename: MingHua
authors.initials: M
authors.lastname: Ge
authors.affiliation: Department of Head and Neck Surgery, Zhejiang Cancer Hospital, 38 Guangji Road, Hangzhou, 310022, China.
authors.forename: LieHao
authors.initials: L
authors.lastname: Jiang
authors.affiliation: Department of Head and Neck Surgery, Zhejiang Cancer Hospital, 38 Guangji Road, Hangzhou, 310022, China.
authors.forename: JiaFeng
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Head and Neck Surgery, Zhejiang Cancer Hospital, 38 Guangji Road, Hangzhou, 310022, China.
authors.forename: ChuanMing
authors.initials: C
authors.lastname: Zheng