Abstract: Objective To investigate the clinical efficacy of three-port gasless intermuscular approach endoscopic surgery for cN0 stage papillary thyroid carcinoma(PTC).Methods A retrospective analysis was conducted on the clinical data of 120 patients with cN0 stage papillary thyroid carcinoma who underwent endoscopic-assisted unilateral radical thyroidectomy between January 2023 and March 2025.Patients were divided into the three-port group(48 cases) and the trans-subclavian group(72 cases) based on the surgical approach.The cumulative sum(CUSUM) method was used to analyze the learning curve for the trans-subclavian group.Based on the curve's inflection point，the group was divided into a learning phase（trans-subclavian group in the learning phase，30 cases） and a technically mature phase（trans-subclavian group in the technically mature phase,42 cases）.Perioperative data，incidence of postoperative complications,incision length，and cosmetic satisfaction were compared between the two groups.Perioperative data，postoperative complication rate，incision length，and cosmetic satisfaction were then compared between the three-port group and the trans-subclavian group in the technically mature phase.Results The trans-subclavian group reached the technically mature phase after the 31rd case.No statistically significant differences were found between the three-port group and the technically mature trans-subclavian group regarding maximum tumor diameter，number of dissected lymph nodes，length of hospital stay，and postoperative complication rate(P>0.05).However，the operative time for the three-port group was significantly shorter than that of the technically mature trans-subclavian group [73.5(64.3，85.8) min vs.90.0(82.8，105.0) min，P<0.01].The three-port group demonstrated superior outcomes in incision length [2.5（2.4，3.0）cm vs 4.4（4.1，5.0）cm]，wound pain score [2.0（2.0，3.0）points vs 3.0（2.0，3.0）points]，and proportion of patients whic were all satisfied with cosmetic(91.67% vs 73.81%) compared to the overall trans-subclavian group(P<0.05).Conclusion The three-port gasless intermuscular approach endoscopic surgery offers distinct advantages in treating cN0 stage papillary thyroid carcinoma，further enhancing cosmetic outcomes and surgical efficiency.

Key words: three-port gasless intermuscular approach; gasless trans-subclavian approach; endoscopy; papillary thyroid carcinoma