Risk factors for contralateral central lymph node metastasis in unilateral cN0 papillary thyroid carcinoma: A meta-analysis

Central lymph node metastasis(CLNM) is common in papillary thyroid carcinoma(PTC). LNM is related to local recurrence and adverse prognosis. The extent of prophylactic central lymph node dissection(pCLND) is not well defined. We aim to investigate the prevalence and risk factors for contralateral central lymph node metastasis (CCLNM) in unilateral clinical node-negative (cN0) PTC patients to determine the appropriate extent of pCLND. A systematic literature search was performed using PubMed and Embase databases until May 2018. Published studies that estimated the association between clinicopathologic factors and CCLNM were included. A total of 6 studies involving 1399 patients were included. The prevalence of CCLNM was 10.9% in all patients. The pooled analysis revealed that male gender (pooled OR = 1.67, 95%CI = 1.11–2.53, p = 0.015), age