Breast cancer lumps can grow anywhere in the breast, and the location of growth varies from person to person, with the outer upper quadrant and inner upper quadrant being the most common, while the inner lower quadrant and outer lower quadrant are less common. To distinguish the location of the lump in the clinic, the nipple is often used as the center, and a “cross” is drawn to divide it into four quadrants, in which the most common breast cancer lumps are located in the upper outer quadrant, the probability of being located in the upper inner quadrant is the second highest, and the probability of being located in the other two quadrants is rare, and the hard lumps of some breast cancer patients are also located in the nipple and under the areola. There is also a special case of hard lumps of breast cancer in patients with the presence of paramedian breasts, which can also be present because of the presence of normal breast tissue in the paramedian breasts. No matter which part of the hard lump is found, once found, it is recommended to go to the hospital in time to improve the auxiliary examination, and then according to the specific condition, surgery, radiotherapy and other treatment measures will be given as soon as possible after diagnosis of breast cancer.