Breast cancer staging cannot be determined simply by the size of the lump, but should take into account the malignancy of the tumor, pathological staging, lymph node metastasis and so on. According to the international TNM staging criteria for breast cancer, a lump of 2-5 cm, excluding lymph node metastasis in the axilla, is an early stage lesion; a lump of 2-5 cm, if lymph node metastasis occurs, is an intermediate or advanced stage breast cancer; a lump of 1 cm or less is an early stage breast cancer; if the lump has no skin lesion and does not affect the skin, chest wall or muscle, it is an early stage lesion; if the lump is smaller, but has a higher malignancy, it may also be an intermediate or advanced stage. However, if the lump is smaller but more malignant, it may also belong to the middle or advanced stage.