The Application of "HUAXI Hole 1" in Reverse-sequence Endoscopic Nipple-sparing Mastectomy With Direct-to-implant Breast Reconstruction

Inclusion criteria: * Female patients aged 18-70 years (inclusive18 and 70 years); * Patients eligible for unilateral or bilateral reverse-sequence endoscopic nipple-sparing mastectomy with immediate implant-based breast reconstruction, with concurrent contralateral endoscopic augmentation mammoplasty permitted; * Patients with preoperative pathological confirmation of non-specialized breast cancer (e.g., ductal carcinoma in situ, invasive ductal carcinoma, invasive lobular carcinoma) or eligibility for prophylactic mastectomy; * For non-specialized breast cancer patients, preoperative tumor size ≤5 cm (post-neoadjuvant chemotherapy if applicable), and no clinical or imaging evidence of invasion to the nipple, skin, subcutaneous fat, chest wall (referring to the bony thorax and intercostal muscles, excluding the pectoralis major and minor muscles) or distant metastasis preoperatively; * Patients volunteered to provide informed consent. Exclusion criteria: * History of open breast surgery within 1 year before this procedure (excluding minimally invasive vacuum-assisted biopsy); * Breast cancer diagnosed during pregnancy or lactation; * Subnipple-plane scarring with radiotherapy; * Metastatic breast cancer (M1); * Severe comorbidities precluding general anesthesia or surgery; * BMI ≥40 kg/m²; * HbA1c \>7.5%; * Immunodeficiency; * Active smoking with ≥20 cigarettes per day * Patients with concurrent participation in conflicting clinical trials.