The global burden of breast cancer continues to increase largely because of the aging and growth of the world population. More than 1.38 million women worldwide were estimated to be diagnosed with breast cancer in 2008, accounting for 23% of all diagnosed cancers in women. Given that the 5-year survival rate for breast cancer is now 90%, experiencing breast cancer is ultimately about quality of life. Women treated for breast cancer are facing a life-time risk of developing lymphedema, a chronic condition that occurs in up to 40% of this population and negatively affects breast cancer survivors' quality of life. It's becoming more and more important to do more research on the breast cancer-related lymphedema. Axillary reverse mapping (ARM) is a technique used to map arm lymphatic drainage during axillary lymph node dissection (ALND) and/or sentinel lymph node dissection (SLND). It's necessary for the investigators to understand the participants' upper limb lymphatic drainage before operation and what the investigators have done on it during operation. It can be easy to understand the influence of operation on the participants' upper limb lymphatic drainage, the possibility and safety of reserving lymph nodes draining the upper extremity lymph.
