RESUMEN
Objective·To evaluate central lymph node dissection (CLND) and intraoperative frozen-section examination in the treatment of papillary thyroid microcarcinoma (PTMC).Methods· Clinical data and neck lymph node metastasis of 187 PTMC patients treated by the same surgeon from October 2012 to November 2015 in Department of Endocrine Breast Surgery,First Affiliated Hospital of Chongqing Medical University were analyzed retrospectively.Results · Postoperative pathology inspection confirmed that 94 of the 187 patients were accompanied with lymph node metastasis in central region,and the metastasis rate was 50.2%.Furthermore,lymph node metastasis rate in central region was not associated with gender and age (P>0.05),but the metastasis rates of the patients with multifocal lesion,tumor diameter greater than 5 mm,capsular invasion,or tumor location in the lower third of thyroid lobe were higher (P<0.05).Twenty-two cases of the 69 patients who underwent CLND were confirmed to have lymph node metastasis in this region.When the number of lymph node metastases in the central region was greater than or equal to 2,the cases were accompanied by increased risk of lymph node metastasis in the cervical region (P<0.05).The diagnosis level of lymph node metastasis in central region by intraoperative frozen-section examination was relatively higher than current cervical lymph node-negative (cN0) standard (P<0.05),which had lower false negative rate (20.2%) than current cN0 standard (88.8%) and was highly consistent with the postoperative pathology in central lymph node metastasis diagnosis (K=0.765,P=0.000).Conclusion· PTMC has high lymph node metastasis rate in the central region.Regular CLND is recommended.Intraoperative frozen-section examination can accurately evaluate cervical lymph node metastasis to help guide operation scope of thyroid and cervical lymph nodes.