Clinical Research Directory

Inclusion Criteria: * female patients aged 18-70 years (inclusive); * preoperative pathological examination confirmed it as invasive breast cancer or ductal carcinoma in situ; * both clinical and imaging examinations clearly indicated that the lesion was a single lesion confined within the gland, without invasion of the skin, subcutaneous tissue, pectoralis major muscle, or the nipple-areola complex; * tumors in the inner and outer quadrants (three classification method, as shown in Figure 2); * preoperative tumor size ≤3 cm (pre-neoadjuvant chemotherapy if applicable); * the tumor is more than 2 cm away from the nipple (the distance is based on physical examination, with MRI and ultrasound as supplementary methods); * the patient has a clear intention to preserve the breast and can receive standard radiotherapy after the operation; * voluntary provision of informed consent. . Exclusion Criteria: * clinically or radiologically evaluated as multifocal or multicentric breast cancer, with diffuse suspicious calcification, long spiculated masses, extensive local resection unable to obtain sufficient negative margins or ideal shape; * persistent positive tumor margins, and resection cannot ensure negative margins after resection; * inflammatory breast cancer; * pregnant and lactating women; * previous history of breast cancer surgery (including patients with recurrence after ipsilateral breast-conserving surgery); * breast cancer genetic gene mutations (such as BRCA1/2 gene mutations); * preoperative severe underlying diseases that cannot tolerate general anesthesia and surgical procedures. * other situations that the researchers consider unsuitable for participation