2. Wedge resection;

3. Quadrant rear intersection is widely used in Europe and America. As for the indications of breast-conserving surgery, there is no unified standard in China at present. It is generally believed that the following conditions should be met when selecting a case:

① Single breast lesion with diameter less than 3 cm, relatively clear boundary and no axillary lymph node metastasis;

② The cancer focus is located around the breast, and the tumor edge is more than 3 cm away from the nipple, which is convenient for postoperative repair and keeps the appearance of the breast beautiful;

③ Patients have a strong subjective demand for breast conservation, and are eligible for comprehensive treatment after operation and long-term follow-up. In addition, considering the postoperative appearance effect, it is necessary to comprehensively evaluate the size of tumor and its ratio to breast, and breast fullness is more appropriate.