ObjectiveTo investigate the effect of lymph node dissection in central region on the prognosis of cN0 papillary thyroid microcarcinoma (PTMC).MethodsAccording to the inclusion and exclusion criteria, 300 patients with cN0 PTMC underwent operation in the Second Department of General Surgery of Zhongshan People’s Hospital from January 1, 2007 to May 31, 2016 were retrospectively collected, then who were divided into the central lymph node non-dissection (147 cases) and dissection (153 cases) groups according to whether central lymph node dissection or not. The differences in the incidence of postoperative complications, recurrence rate, and metastasis rate between the two groups were analyzed. The risk factors of central lymph node metastasis of cN0 PTMC were analyzed.ResultsAll patients had no postoperative lymphatic leakage and death. Fifty-nine (38.6%) cases had the lymph node metastasis in the patients with central lymph node dissection. The patients were followed up for (83.0±20.7) months and (79.5±26.2) months (t=1.283, P=0.203) of the non-dissection group (147 cases) and dissection group (153 cases), respectively. During the follow-up period, there was no distant metastasis such as bone metastasis and lung metastasis in both groups; 5 cases recurred in the non-dissection group, 1 case recurred in the dissection group, and there was no significant difference in the recurrence rate between the two groups (χ2=3.008, P=0.089). There was no permanent complications between the two groups. There was no significant difference in the disease-free survival curve (χ2=2.565, P=0.109) between the two groups. The incidence of capsule invasion (P=0.026), calcification (P<0.001), hoarseness (P=0.013), numbness of limbs (P<0.001) in the dissection group were significantly higher than those in the non-dissection group. The results of multivariate analysis showed that the multifocal (OR=24.57, P<0.001), tumor diameter >5 mm (OR=5.46, P=0.019), and capsule invasion (OR=9.42, P=0.002) were the independent risk factors for the lymph node metastasis in the central region.ConclusionsFrom the results of the study, thyroidectomy alone is safe for cN0 PTMC, but the changes of lymph nodes in the central region still need more long-term follow-up. cN0 PTMC patients with tumor diameter >5 mm, multifocal, and capsule invasion are more likely to have lymph node metastasis in the central region. Comprehensive evaluation can be made according to the patient’s condition, and individualized and precise treatment can be carried out.