ObjectiveTo compare the differences in surgical efficiency, surgical safety, aesthetic outcomes, and oncological safety between axillary single-incision endocsopic breast-conserving surgery (ASIEBS) and conventional open breast-conserving surgery (COBS), and to evaluate the clinical value of ASILBCS based on the “HUAXI hole 3” technique. MethodsA retrospective cohort study was conducted on the clinicopathologic data of patients who underwent breast-conserving surgery for breast cancer at West China Hospital of Sichuan University from January 2021 to September 2024. The patients were assigned into an ASILBCS group and a COBS group based on the surgical approach. Both groups received standardized surgical treatment and postoperative follow-up. The observation indicators included baseline characteristics, intraoperative data, postoperative complications, aesthetic outcome (by Ueda score and Harris score evaluation), and oncological safety (local recurrence and distant metastasis). ResultsA total of 67 patients were enrolled, with 41 in the ASIEBS group and 26 in the COBS group. There was no statistically significant differences in the comparison of other baseline data between the two groups (P>0.05), except for the proportions of patients with diabetes mellitus and those positive for human epidermal growth factor receptor 2 (P＜0.05). The ASIEBS group showed superior aesthetic outcomes compared to the COBS group (Ueda score: P=0.013; Harris score: P=0.047). However, the ASIEBS group had higher median total hospitalization costs (12 779.00 yuan vs. 12 354.50 yuan, Z=–2.16, P=0.03). The median follow-up time was 31.43 months in the ASIEBS group and 21.20 months in the COBS group (Z=–2.36, P=0.02). During follow-up, only one patient with local recurrence occurred in the ASIEBS group, and no distant metastasis or death event was observed in both groups. ConclusionThe ASIEBS based on the “HUAXI hole 3” technique is comparable to COBS in terms of surgical efficiency, surgical safety, and oncological safety, while offering superior aesthetic outcomes.