Predictive Risk Factors for Recurrence or Metastasis in Papillary Thyroid Cancer

Abstract

Background and Objectives: This study investigated predictive risk factors for cervical nodal recurrence or metastasis in papillary thyroid carcinoma (PTC). Materials and Methods: From September 2014 to February 2015, a total of 321 PTC patients were enrolled retrospectively. Except for 154 N0 patients, the remaining 167 patients were divided into two groups as follows: Group I (n=140), central lymph node (LN) metastasis (pN1a); Group II (n=27), lateral LN metastasis (pN1b, n=23) or LN recurrence (n=4). The patients who had LN metastasis or recurrence underwent selective LN dissection or recurrent LN excision. Results: Central LN metastases were found in 44.0% (142/321) of patients. Two hundred thirty patients (71.7%) were classified as being at low-risk for LN disease, as evidenced by N0 or fewer than five micrometastases. The mean size of central metastatic LNs was 0.37±0.34 cm. A total of 76 patients (46.6%) presented with micrometastasis, and ten (3.1%) presented with extranodal extension (ENE). The multiple/bilateral cancer, Extrathyroidal extension, size of metastatic LN, ENE, high risk LN disease (＞5, macrometastasis, ＞3.0 cm) and high thyroglobulin were significant risk factors in predicting LN recurrence or lateral LN metastasis (p<0.05) in univariate analysis. Patients with ENE were 10.3 times more at risk for recurrence or metastasis than patients without ENE. Conclusion: We consider the ENE was the most potent risk factors for LN recurrence or lateral LN metastasis in PTC.