I. Introduction 1. High-tech design ensures safety: unique hollow puncture needle design, only one puncture throughout the operation, avoiding needle tract metastasis caused by repeated multiple punctures of tumor cell shedding. 2, more accurate diagnosis: biopsy of suspicious lesions can obtain large and continuous specimens, and the sample volume taken in one puncture is 8 times of the traditional hollow thick needle, which reduces the false negative rate of pathology by 50% (malignant tumor cells are not detected and misdiagnosed as negative due to small and limited specimen volume); and marker clips can be placed at the biopsy site to observe whether the lesion has malignant changes at any time. 3, low infection rate, more economical: conventional surgical incision application of electrocoagulation to stop bleeding is likely to cause fat liquefaction, surgical sutures as a foreign body retained in the incision, are prone to cause incision infection and poor healing; McMurdo surgery is less damage to normal tissues, no foreign body remains in the body, the risk of infection is significantly reduced, saving anti-infection costs. 4, fast and convenient surgery: short surgery time, light pain, single swelling 10-30 minutes, after surgery can be free to move. 2. Indications for McMurdo surgery 1. Benign breast masses less than 3.5 cm, fibroadenoma, nodules, asymmetric density, multifocal lesions and microcalcifications. 2.Breast masses (<3 cm) of unknown pathological nature that require excisional biopsy. Contraindications for McMurdo surgery 1. Patients with suspected breast cancer can be biopsied, but lump rotation surgery should be avoided; 2. Patients with bleeding tendency, hemangioma and diabetes mellitus are contraindications for surgery. If the lump is located in the areola and the diameter is >3.5cm, the surgery should be performed with caution.