Objective  To investigate the risk factors for central lymph node metastasis (CLNM) and lateral cervical lymph node metastasis in papillary thyroid carcinoma (PTC) patients.

  Methods  We retrospectively reviewed 1, 835 PTC patients who underwent central lymph node dissection or thyroidectomy with lateral cervical lymph node dissection between January and November 2016 at Tianjin Medical University Cancer Institute and Hospital. Univariate and multivariate logistic regression models were used to analyze related factors that may affect lymph node metastasis in PTC patients.

  Results  Of the 1, 835 patients included in this study, 1, 007 (54.88%) patients had CLNM and 371 (20.22%) patients had lateral cervical lymph node metastasis. In the univariate analysis, the following were identified as risk factors for CLNM and lateral cervical lymph node metastasis (P < 0.05): male sex, age < 45 years, primary tumor size > 10 mm, multifocality, anti-thyroglobulin (anti- Tg) levels >100.00 IU/mL and, Tg>130.70 μg/L. Anti-thyroid peroxidase antibody (antiTPO) level >100.00 IU/mL is a protective factor that reduces the risk of CLNM. However, CLNM is a risk factor for lateral cervical lymph node metastasis in PTC patients. Multivariate analysis revealed that male sex, age < 45 years, primary tumor size >10 mm, multifocality, and anti-TG levels >100.00 IU/mL were associated with an increased risk of CLNM in PTC patients. Anti-TPO levels >100.00 IU/mL are protective factors for CLNM. The male sex, age < 45 years, tumor size >10 mm, multifocality, Tg levels >130.70 ug/L, anti-TG levels > 100.00 IU/mL, and CLNM are risk factors for lateral lymph node metastasis.

  Conclusions  Thus, men aged < 45 years with a multifocal primary tumor >10 mm in size and with anti-Tg levels >100.00 IU/mL are more likely to develop CLNM and lateral cervical lymph node metastasis; patients with CLNM are more likely to develop lateral cervical lymph node metastasis. However, patients with anti-TPO level >100 IU/mL are less likely to develop CLNM.