The breast is located on the surface of the body, and the clinical manifestations of breast cancer are relatively typical. Early symptoms of breast cancer are as follows: 1. Lumps: Most of the patients visit the clinic with lumps in the breast. The lumps in the breast of adult women should be taken seriously. Most breast cancers are single and rarely multiple lesions are seen in the same breast. The shape of the lump varies widely and is generally considered irregular with unclear edges and a hard texture. In early stages, cancerous lumps are limited to the breast parenchyma and can still be pushed, but they are not as mobile as benign tumors, and once they invade the fascia or skin, the lumps cannot be pushed and the stage of the disease is late. Breast cancer mostly occurs in the upper part of the breast, accounting for more than 50% of the cases, with the most frequent occurrence in the upper quadrant of the breast, which is related to the fact that there are more outer upper breast lobes. Breast cancer originates from the epithelium of the glandular ducts and is difficult to detect in situ; a lump of about 0.5 cm is difficult to detect if it is deep in the large breast, while a lump of 1 cm or more is easy to detect. There is also a rare type of breast cancer called occult breast cancer, whose lumps in the breast cannot be detected but have metastasized in the axilla. 2. Pain: Most patients have no obvious pain, a few patients go to the doctor with pain, which is mostly paroxysmal stabbing pain or hidden pain. The pain is mostly paroxysmal stabbing pain and vague pain. The pain is not serious in the late stage. 3, nipple overflow: nipple fluid can be physiological or pathological, the incidence of non-pregnancy lactation nipple overflow is about 3% to 8%, the overflow can be colorless, milky white, yellowish, brown, bloody, etc., but also watery, blood-like, plasma-like pus; the amount of overflow can be more or less, the interval also varies, patients often consult the doctor because the overflow contaminated underwear. Smear cytology should be performed for clarification of nipple overflow. Most breast cancers are associated with breast lumps. Nipple discharge alone is a rare symptom. 4. Skin changes of breast: Skin changes of breast cancer are related to the depth of the lump site and the degree of invasion. If the lump is small and the site is deep, there is no change in the skin; if the lump is large and the site is shallow, it will adhere to the skin at an early stage, making the skin appear sunken and the dimple sign. If the cancer cells block the subcutaneous lymphatic vessels causing skin edema and forming cellulite-like changes, it is a late stage manifestation. 5. Nipple change: Normal people have bilateral breast symmetry, but when there is cancer near the nipple, the nipple is often pulled upward, so the nipple height is different. Nipple invagination is an important sign of carcinoma in the central area of the breast. It is difficult to pull out the nipple with fingers and the nipple is in a fixed retracted state. In the case of eczema-like carcinoma, the nipple is vesicular and often has scabs; the lesion area is very clearly demarcated from the skin, and the lesion area is very clearly demarcated from the skin, and the lesion skin is thicker. 6.Change of breast shape: normal breast shape is naturally curved, if the curvature is abnormal, attention should be paid to the occurrence of cancerous tumors.