Group inclusion criteria
Breast Cancer, stage-II breast cancer, tumor
TUMOR, INFILTRATION, BREAST CANCER, METASTASIS, SENTINEL LYMPH NODE

Each patient should be informed of and consent to his or her treatment;A patient should have clinical stage-I or stage-II breast cancer, without obvious skin or deep infiltration, and his or her axillary lymph node should be categorized as N1 or N0 via ultrasonic, X-ray, and breast nuclear magnetic resonance clinical examinations. However, SLNB should be performed during the procedure. The metastasis of a sentinel lymph node should be shown by intraoperative frozen sections. The TNM staging system in the NCCN Guidelines for Breast Cancer was adopted as the criteria for clinical stagingA patient should have the prescription for mastoscopic axillary lymph node dissection, and specifically: (a) have the indications for a routine axillary lymph node dissection; (b) he or she should not have a history of axillary surgery; (c) through clinical examination, ultrasound, and X-ray examination, a patient’s axillary lymph node should be less than grade N2; (d) an intumescent lymph node should not adhere to blood vessel and nerveA patient should conform to the indications for breast-conserving surgery: (a) the maximum tumor diameter should be 3 cm, and after the surgery, the breast must have been able to keep proper volume and contour; (b) the tumor had not invaded nipple and areola; (c) should not have multifocal or multi-quadrant tumor lesion; (d) could undergo radiotherapy; (e) the tumor is not located at the edge of the gland and can through an areolar incision.