• Female patients, aged 18-75 years old; The pregnancy test (-) and reliable contraceptive methods are required for premenopausal and perimenopausal patients;

• Patients with the diagnosed breast cancer confirmed by core needle biopsy and unilateral operation was performed; Breast cancer patients with tumor node metastasis stage 0-III according to the 8th edition of the American Joint Commission on Cancer; Preoperative clinical examination or imaging evaluation shows that the distance between the tumor and the Nipple Areolar Complex (NAC) is more than 1cm. The tumor has a diameter of 2-3 cm and can be located in any quadrant or reduced to 3 cm through preoperative neoadjuvant chemotherapy. The distance between the lesion and the skin should be at least 8-10 mm;

• There is no clinical or imaging evidence to prove that the tumor has invaded the skin, chest wall, or nipple areola complex;

• There are indications for breast preservation, but the patient has a strong desire for reconstruction and is unwilling to undergo breast preservation surgery;

• Preventive mastectomy (BRCA1/2 malignant mutation with obvious family history of breast cancer and other high-risk groups);

• Preoperative clinical manifestations and imaging data showed no distant metastasis;

• No history of breast cancer or other serious underlying diseases in the past;

• Karnofsky performance status score ≥ 70;

• Eastern Cooperative Oncology Group score ≤ 2 ;

⁃ The surgical procedure includes endoscopic-assisted/conventional mastectomy, sentinel lymph node biopsy/axillary lymph node dissection and immediate breast reconstruction;

⁃ Participants are able to understand the research process, voluntarily join the study, sign informed consent forms, have good compliance, and cooperate with follow-up;

⁃ No swallowing difficulties; No shoulder joint movement disorders;

⁃ Complete clinical data.