Clinical Characteristics Related to Central Lymph Node Metastasis in cN0 Papillary Thyroid Carcinoma: A Retrospective Study of 916 Patients.

Background. Papillary thyroid carcinoma (PTC) is a form of thyroid cancer with high risk of cervical lymph node metastasis. Aim. The aim of this study was to investigate the incidence and the predictive factors for occult ipsilateral central lymph node (CLN) metastasis in the patients with papillary thyroid carcinoma. Methods. A total of 916 PTC patients (1017 lesions) undergoing central lymph node dissection in our hospital from 2005 to 2011 were enrolled. The relationship between CLN metastasis and clinical factors such as gender, age, tumor size, tumor number, capsule invasion, and tumor location was analyzed. Results. Occult CLN metastasis was observed in 52.41% (533/1017) of PTC lesions, respectively. Multivariate analysis showed that age ≤ 35 years, tumor size > 1.5 cm, present capsule invasion/extracapsular invasion, and tumor located in upper/middle pole/whole lobe were risk factors of CLN metastasis. Conclusions. Tumor located in upper/middle pole/whole lobe, less than 35 years old, tumor size > 1.5 cm, and present capsule invasion/extracapsular invasion were risk factors of CLN metastasis. We recommend performing ipsilateral prophylactic CLN dissection in cN0 PTC patients.