Objective To study the risk factors of lymph node metastasis in the central neck compartment of thyroid carcinoma,and to explore the reasonable range of lymph node dissection in central neck dissection for clinically node-negative papillary thyroid microcarcinoma patients.Methods From Dec.2015 to Dec.2016,a total of 200 patients with CN0 papillary thyroid carcinoma were randomly divided into two groups according to the registration number:unilateral central neck dissection group and bilateral central neck dissection group in Department of Thyroid Surgery,Fujian Medical University Union Hospital.The risk factors of lymph node metastasis and value of bilateral central neck dissection were analyzed.Results The risk factors of lymph node metastasis in the central papillary thyroid carcinoma were ≥0.7 cm in diameter and older than 45 years in age and gender in male.Further analysis found that contralateral central lymph node metastasis occurred in patients with tumor diameter ≥0.5 cm.The positive rate was 22％.The number of lymph nodes detected in the unilateral and bilateral central areas was 9.53±6.04 and 12.19±7.18,P=0.035,respectively.The positive numbers of lymph nodes were 1.17±1.47 and 2.11±2.75,P=0,022 respectively.Conclusion In patients with tumor diameter ≥0.5 cm,bilateral central neck dissection is conducive to improving the thoroughness of tumor dissection and does not increase the risk of complications.

O bjective To understand the effects and clinical significance of the 2019 guidelines for the human epidermal growth factor receptor 2 (HER2) detection. Methods:According to the 2014 guidelines, 548 cases of invasive breast cancer with equivocal HER2 (2+) detected by immunohistochemistry (IHC) in Taizhou Enze Medical Center, Zhejiang Province, China from 2013 to 2019 were selected. The results of IHC and HER2/CEPl7 double-probe were reevaluated and divided into groups according to the 2019 guidelines for the comparative analysis.Results:Among the 548 IHC HER2 (2+) invasive breast cancers, the number of positive, equivocal and negative cases for HER2 were 96 (17.52%), 81 (14.78%) and 371 (67.70%), respectively, according to the 2014 guidelines. However, according to the 2019 guidelines, 10 cases (1.82%) were reclassified as IHC 1+, 2 cases in the group 2 were reclassified as negative, and all the originally equivocal cases in group 4 were reclassified as negative. Finally, the total number of positive and negative cases for HER2 were 94 (17.15%) and 454 (82.85%), respectively.Conclusions:After applying the 2019 guidelines, the number of IHC 2+ cases decreases, and the positive rate for HER2 also decreases slightly due to the reevaluation change in groups 2 and 4, leading to reclassification of the cases that were deemed equivocal according to the 2014 guidelines. In general, the new 2019 guidelines are more reasonable and easier to use.