1. Breast lump: The main manifestation of breast cancer is a lump growing on the breast, which is often an early symptom of breast cancer. Most of the patients do not feel any pain, only less than 1/3 of them feel some tingling or dull pain, but it is not very obvious. About 60% of the lumps grow on the outer upper part of the breast and are round and irregular in shape. There is no infiltration of cancer tissue in the early stages. The lump can still move. However, since the lump of breast cancer is very similar to benign breast tumor in many aspects, it is inaccurate to determine its nature by touching the lump alone and must be examined in hospital. 2. Unilateral nipple overflow: Non-lactating women who suddenly have nipple flow (milk-like, blood-like or water-like liquid) should be noted because some of them are breast cancer patients.