Oncoplastic breast surgery is an important advancement in breast surgery. The concept is to use the principles and surgical techniques of breast reduction or breast fixation to fill the defect and reshape the breast by rotating and moving the breast flap in the same operation after mastectomy. Features: Unlike the first-stage breast reconstruction using the latissimus dorsi and rectus abdominis muscles, it can ensure complete removal of breast cancer, clean surgical margins, small surgical incisions, less bleeding, shorter operation time, rapid postoperative recovery, beautiful and symmetrical breast shape, and no increase in postoperative recurrence rate. Advantages: 1. Preservation of breast shape can improve the quality of life, improve the function of the affected upper limb and reduce surgical complications; 2. If recurrence occurs in the affected breast after breast-conserving surgery, remedial total mastectomy can also be performed, which can still achieve the same long-term survival rate as conventional radical surgery. If the tumor is located in the same quadrant of one breast, breast conservation is also possible; 2.peripheral breast cancer, if the tumor is located outside the areola and nipple, or below or near the nipple areola, it is difficult to preserve the nipple areola complex and requires reconstruction; 3.breast cancer with tumor diameter ≤3cm; 4.if the tumor diameter is >3cm but ≤5cm, preoperative chemotherapy can be performed first to shrink the tumor. Breast-conserving surgery is still feasible if the tumor is less than 3 cm; 5. Breast-conserving surgery is also feasible for breast cancer with positive axillary lymph nodes; 6. Breast-conserving surgery is suitable for invasive ductal carcinoma, but not for invasive lobular carcinoma, which is prone to multiplicity; 7.