[Risk factors analyses for lateral neck lymph node metastasis in papillary thyroid carcinoma]

Objective:To study the risk factors for the lateral neck lymph node metastasis(LNM) in patients with papillary thyroid carcinoma(PTC).Method:Total 145 cases of papillary thyroid carcinoma patients were reviewed. These patients were divided into the following 2 groups: a lateral LNM-positive group and a lateral LNM-negative group.Clinical factors and tumor ultrasound characteristics were recorded, and the final pathology results were recorded as well. Result: Univariate and multivariate analyses indicated that primary tumor size(pathological diameter) >1.0 cm, upper portion location and lymph node metastasis in central neck were the three risk factors for lateral LNM of PTC(OR=6.250,4.881,5.222,P<0.05). The lymph node metastasis in the lateral neck was not correlated obviously with gender, age, capsuleinvasion, multifocality and tumor ultrasonic characteristics(including illdefined and irregular in shape, calcification, hypervascularized). The probability of lateral LNM was then calculated according to the number of risk factors present in each of the 145 patients, using the three factors. When two or more factors were present, the probability increased up to 38.1 %(95%CI23-53).Conclusion: The present study provides that lateral LNM occurs mainly in patients, with a tumor size(pathological diameter) diameter>1.0 cm, with the primary tumor located in the upper part of the lobe and positive central compartment lymph node metastasis. The risk increased up when at least two of the three factors were present. So it needs to pay attention to the high risk factors seriously which effect lateral neck lymph node metastasis in patients with PTC, combined with ultrasonic characteristics of lateral cervical lymph node or more meticulous evaluations, to establish the lymph node dissection individually.